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The deep ocean, exceeding 200 meters in depth, represents Earth's largest habitable space, yet it remains its least explored region. This study focuses on the Southern California Borderland (SCB), an area characterized by uneven and heterogeneous topography; and varying depths, temperatures, and oxygen concentrations. Due to its variability, this environment serves as an optimal setting for investigating the relationship between mineral-rich hardgrounds and benthic fauna. The deep ocean plays a crucial role in resource provisioning, but human activities, including deep-seabed mining, may threaten these oceanic functions. Two mineral-rich substrates, ferromanganese (FeMn) crusts and phosphorite rocks, are among the deep ocean mineral types being considered for their resource potential due to their enrichment in valuable metals in some regions. However, these geological features support deep-ocean biodiversity by acting as specialized substrates for macrofaunal communities and enabling key biogeochemical processes. This study aims to characterize macrofaunal (> 300 μm) density, diversity, and community composition on mineral-rich substrates in the SCB, focusing on FeMn crusts and phosphorite rocks. Macrofaunal samples were collected using remotely operated vehicles (ROVs) during expeditions in 2020 and 2021. Through quantitative analysis, I explore the faunal association with different substrate types, sites in the SCB, and various environmental variables, including oxygen, depth, temperature, and proximity to shore. Additionally, I assess the relationship between megafauna presence and macrofaunal density and diversity. A total of 3,555 macrofauna individuals were counted and 417 different taxa were identified from 82 rocks from depths between 231 m and 2,688 m. Average density for SCB macrofauna was 11.08 ± 0.87 individuals /200 cm2 and mean diversity per rock was H’(loge) = 2.22 ± 0.07. A relationship was found between site, substrate type, and macrofaunal communities. Phosphorite rocks had the highest diversity on a per-rock basis and when pooled, FeMn crusts had the highest number of species. Of all the environmental variables, depth explained the largest variance in macrofauna community composition. Macrofauna density and diversity had similar values at sites within and outside the oxygen minimum zone (OMZ). Understanding the intricate relationships between macrofaunal assemblages and mineral-rich substrates is essential, especially in the context of environmental disruptions associated with deep-seabed mining or climate change. This study is the first to analyze the macrofaunal communities of mineral-rich hard substrates in the SCB. The findings contribute crucial baseline information for effective conservation and management of the SCB and will support scientists in monitoring changes in these communities due to environmental disturbance or human impact in the future.

Expanding invasive herbaceous vegetation (non-native grasses and forbs or herbs) is replacing portions of native shrublands in San Diego County, California, USA through a grass-fire cycle, which contributes to an increased risk of wildfire ignition and spread as well as a changing fire regime. Despite the association between herb abundance and wildfire risk, remote sensing and image processing approaches for quantification of fractional herb cover in shrublands are not well established, nor is the association between herb fraction and proportion of ignitions. In this research, I comparatively assess the accuracy of herb cover estimation and mapping based on three spectral unmixing models applied to Landsat-derived spectral reflectance and spectral vegetation index data from multiple 2020 dates. Based on the model and methods that most accurately and reliably represent herb cover, I then reconstruct the spatial-temporal distribution of herb growth using Landsat images from 1988, 1997, and 2011 and assess the extent to which herb cover has expanded and replaced woody vegetation cover (1988 to 2020). Finally, I combine the herb cover maps with historical ignition points to evaluate the spatial association between herb fractions and locations where fires initially ignited and spread (1992 to 2020). When compared to generated reference data, results demonstrate the parsimonious spectral unmixing approach applied to a fall date estimates herb cover at the 10% accuracy level and more accurately than the more sophisticated unmixing models. Absolute change estimates derived from the earliest and most recent herb cover maps show approximately 25% of the study area exhibited an increase in herb cover > 20%, and roughly 5% experienced a decrease in herb < -20%, with the greatest concentration of change occurring in wildland-urban interface areas. Factors most strongly associated with substantial increase in herb cover include fire return interval, drought, proximity to development, and elevation. The results of evaluating historical ignitions in herbs show the largest proportion of ignitions occurred in areas with > 20% herbaceous fractional cover. Results from this study will enable improved detection of sensitive habitats by satellite for wildfire-prone communities and help identify target areas for mitigating and combating the grass-fire cycle.

This dissertation tells the story of the founding and development of Mount Wilson Observatory (MWO) during the early twentieth century. Located in the San Gabriel Mountains, just north of Los Angeles in Southern California, this astronomical observatory was founded in 1904 by astrophysicist George Ellery Hale with financial funding from the Carnegie Institution of Washington. I consider MWO as a factory of science: an observatory that efficiently produced a variety of astronomical knowledge. Hale was the factory manager who led the effort to locate a suitable site for the factory observatory, secured patrons, built the infrastructure, hired scientific workers, and expanded his enterprise by marketing his scientific resources and products. In doing so, I extend the focus from prominent astronomers and instruments typically associated with MWO to include the role of sociocultural and natural environments in shaping scientific practices.I argue that MWO was not a scientific inevitability but a regional contingency that reflected Southern California's sociocultural and natural environment. Emphasizing Hale's management style, which he had honed from a young age, I show that the site survey and regional patrons played a vital role in securing the Carnegie Institution's patronage to establish the factory observatory. The trail widening up Mount Wilson served as establishing infrastructure, an example of tangible regional investment, and a case of how white settlers used marginalized immigrant labor to accelerate the development of Southern California. By examining how astronomers, telescope operators, and human computers created scientific products, I highlight the nuanced gender dynamics of the scientific workers and how spatial layouts enforced existing sociocultural norms. I explore how the factory observatory expanded and gained prominence in the scientific community through the astronomers' use of unique scientific resources at the observatory, such as the Snow Solar Telescope and the 60-inch reflector telescope. By taking such a view, I connect Hale and MWO with the industrialization of the United States during the nineteenth century, the growth of Chicago and Southern California during that time, the role of sociocultural biases and assumptions, and the utility and limitation of the natural environment posed.

The following dissertation explores the intersections of religion and daily life among Latino migrant day laborers in Santa Ana, California. Drawing from three years of ethnographic fieldwork, including participant-observation and interviews, conducted in a retail parking lot, this study illuminates the struggle for faith among individuals denied traditional forms of economic, social, and institutional stability. The men on whom the dissertation focuses—migrants from Mexico, Guatemala, and El Salvador—must live and believe without steady employment, housing, familial networks, basic legal rights and, significantly, membership in churches. Their expressions of faith reveal a drive not merely for divine guidance, but for the foundational terms of faith itself.For these migrant workers, faith is more than mere adherence to doctrine or passive acceptance of God's Word. It is a dynamic and precarious negotiation: a conversation both deeply personal and irreducibly social, practiced and disciplined amidst near total instability. The workers’ narratives of faith—including the most rapturous and sublime experiences—reflect the empirical and deeply human realities of their terrestrial lives. These stories shed light on their identities as racialized migrants, as exploited workers, and as men. They touch on themes of family, history, memory, life, death, and mourning, all within the context of Southern California today. The spiritual journeys of these laborers are grounded in Southern California’s socio-historical landscape, itself unstable and prone to sudden shocks, shifts, and upheavals. Touching on the history of land, development, and culture in the region, coupled with insights into U.S.-Mexico border migration, this study gestures outward to macro-level phenomena through the particularities of lived experience.“Challenging Orthodoxies” evokes both obstacle and action. It underscores the intricate ways in which faith, both social and personal, collective and euphoric, plays out in the lives of those to whom community and, in many cases, personhood are routinely denied. Highlighting the resilience, agency, and redemption of migrant day laborers as they found and find the paths of spiritual voice, the dissertation tracks the interplay between understanding and obscurity, discipline and prophecy, light and dark.

In 1769, the Spanish moved to establish sovereignty over Upper or Alta California, by founding Catholic missions, military outposts, and towns on the far northern frontier of their empire. Their reliance on cattle and horses sustained these efforts but also changed the ecosystems of the indigenous populations. Domesticated animals fed on vegetative sources of Native American foods, medicines, tools, and weapons. Europeans and their horses, cattle, sheep, pigs, and poultry also brought diseases that claimed the lives of tens of thousands of California Native people. Since the naturally increasing herds posed an existential threat to the southern California Natives, this study seeks to determine how they survived and continued to assert sovereignty in the face of that and other threats. Southern California Indian peoples did not waver in their assertions of sovereignty when Mexican governors granted mission lands to rancheros and they maintained their rights amidst the multiple traumas that accompanied American rule. The study further contends that the essential role played by southern California Indians in the success of Spanish, Mexican, and American cattle ranching, added honor to evolving Native tribal identities. California Indian cattle ranching and cowboying can claim origins in the Spanish horse and cattle culture that developed in response to the wartime conditions of the Reconquista on the Iberian Peninsula as far back as 1100 CE. There, a relatively few mounted vaqueros provided a valuable food source that supported the war effort. In New Spain, a relatively few Indian vaqueros made success more likely in the risky ventures of empire-building. Historical records from Spain to California contain few Native voices. However, both action and inaction are decisions, and invite inference. “Reading against the grain” provides a measured analysis of how and why southern California Indians chose to adopt and modify ideas perceived as beneficial, and rejected and resisted others that did not. Cahuilla, Kumeyaay, Luiseño, and Serrano survival depended on their adapting to changed conditions and working as cowboys on the missions, Mexican ranchos, and American cattle operations. Not satisfied to only provide labor as cowboys for the benefit of others, they drew on their experiences to acquire and run their own herds and formed a new southern California Native American economy based on cattle. In so doing, they had asserted both personal and group sovereignty. Further, they incorporated the family traditions of cowboying that fathers and mothers gave to sons and daughters, as new-traditional and part of an evolving tribal identity.

A combination of complex geological and climatological history in California have created a biodiversity “hotspot” with numerous endemic species. Most of the wetlands in the region, such as rivers and coastal lagoons, were shaped by uplift, sea-level change and climatic fluctuations creating a physical template on which genetic diversification of the aquatic biota could unfold. Coastal lagoons, for example, provide important ecological services as well as habitat and nursery for endemic and endangered animals, such as the steelhead (Oncorhynchus mykiss), red-legged frog (Rana aurora draytonii), and the tidewater goby (Eucyclogobius newberryi). However, anthropogenic impacts on the landscape, such as urbanization and water management for human use and/or flood control, have had major impacts on the landscape threatening much of the fauna associated with these wetlands. Such is the case of the rare and endangered unarmored threespine stickleback, Gasterosteus aculeatus williamsoni, found in only a few drainages in southern California. Most of the populations are now extirpated and those that persist have suffered isolation and bottlenecks, as well as inadvertent mixture of distinct lineages and introduction of non-native predators. Many conservation and restoration efforts led by numerous governmental units and NGOs are underway in California. These require decisions informed by more comprehensive understanding of current and extirpated populations, as such information will lead to more successful and effective planning and management. Advancements in molecular techniques, particularly the development of high-throughput sequencing, has made it possible to not only deepen our knowledge on evolution but also to use it as a tool in conservation biology. This revolution allows us to unravel genomic signals of demography and selection, investigate historic data from museum material, and even look at environmental samples collected from soil and water. All the work presented here explores the use of high-throughput sequencing and bioinformatic tools to target relevant conservation issues related to endangered species and habitats in southern California. We expect that results will have an impact on conservation efforts, and techniques can be applied to other systems and fields of interest.

About 75% of the streams and rivers in Southern California are biologically degraded. Widespread development and flood control have created an urban river condition known for geomorphic simplification, reduced societal value of stream systems, and ecological simplification. The global degradation of streams has resulted in a freshwater biodiversity crisis that, by many measures, eclipses terrestrial biodiversity loss. However, while responsible for many pressures to ecosystems, cities can enhance aspects of ecosystem health and aid in reducing biodiversity loss. Cities can also host the ecosystem services, however degraded, that enhance community cohesion, resilience, and well-being. A growing urban river revitalization movement in the region, in various states of implementation, offers an opportunity to critically examine the opportunities and challenges that are presented by our local urban rivers. In this dissertation, I identify cultural ecosystem services (CES) along the Los Angeles River using FlickR data and examine the relationship between CES and site attributes using Maxent, a presence-only species distribution model. I find that I am able to identify 5 typologies of CES using FlickR text and photos, that two reaches of the Los Angeles River, a completely channelized and a semi-natural, soft-bottom reach of the River, host the highest CES intensity, and that relative suitability of CES occurrence is related to the presence of historical bridges, access, and median flow. Then, using a more traditional application of Maxent, I examine avian species habitat relationships at the catchment scale for species found along urban and semi-natural streams in Southern California. I find that I am not able to identify predictors of habitat suitability for generalist species at the catchment scale, in part due to contradicting model evaluation metrics, and describe limitations with the use of citizen science data, catchment scale analysis, model valuation, and the application of Maxent to highly urban settings. Finally, following statewide investments in green infrastructure projects that enhance water quality and water capture and recognizing the opportunity to support urban biodiversity in distributed multi-benefit projects, I make use of the Delphi method and the expertise of biodiversity experts to identify habitat goals for green infrastructure projects and associated metrics. I describe the Delphi process and the difficulty in reaching consensus due to disagreement in the feasibility and likelihood of success for several goals and objectives. I describe a preliminary framework to capture the habitat value of green infrastructure projects and compare it to established biodiversity frameworks.

Microfibers in the marine environment pose a threat to aquatic ecosystems and organisms, as well as to humans. Most microfibers are land-based and are transported to the ocean via different processes, including through wastewater effluent and riverine discharge. Measurements of microfiber (MF) concentrations in Southern California coastal surface waters, collected approximately monthly from archived samples between 1983-2019, were available for study and were used in this paper to examine the role of climate in explaining variability in microfiber concentrations. These MF measurements were distinctly non-Gaussian, measuring mostly between 10-50 fibers per 50mL, and showed no seasonal cycle. Time series data was collected for five climate variables (coastal upwelling, precipitation, significant wave height, wind speed, and tidal level), and regression analyses between these variables and MF concentrations were conducted. This study shows that the concentration of microfibers in surface waters in the La Jolla area do not correlate with weather and climate events that presumably would transport microfibers to the marine environment. No more than 1% of microfiber variability can be explained by any variable investigated.

This thesis presents methods to place landing sites for the Urban Air Mobility (UAM) concept. The analysis shows an integrated approach to establish UAM landing site requirements, place landing sites based on predicted demand, and estimate the costs associated with UAM landing sites. This thesis also makes estimates of fares associated with UAM operations. The methods presented are applied to three large urban centers in the United States. The analysis assumes an all-electric, advanced multi-rotor aircraft with autonomous navigational and Vertical Takeoff and Landing (VTOL) capabilities to estimate UAM landing site requirements. The thesis presents the land area requirements of UAM landing sites using Federal Aviation Administration heliport design criteria considering ground-taxi configurations. The analysis performed employs a UAM vehicle with an equivalent Rotor Diameter (RD) of 43 feet. In this thesis, UAM demand is estimated using a mode choice model developed in a companion study (UAM Scenario Analysis). The methodology to locate UAM landing sites includes splitting and consolidation of UAM landing sites considering the Zillow Transaction and Assessment Dataset (ZTRAX) to introduce land-use size and cost constraints. The sites are split using a K-Means clustering method and are consolidated using a simple center of mass approach where the demand of each landing site is analogous to mass. The results presented in this thesis apply to 75 and 200 landing sites in each region and assume passenger Cost-Per-Mile (CPM) of $1.20 and $1.80, respectively. This thesis presents a comparative study on how the availability of land affects the splitting, consolidation, and relocation of UAM landing sites for each region, the number of landing sites, and the cost per passenger-mile.

The limited timespan (several decades) of dissolved oxygen (DO) instrumental records precludes a complete picture of how DO in seawater have changed in the past, and thus high-resolution paleo-DO reconstructions are essential for revealing DO variability on centennial to millennial timescales. A rapid and simultaneous bulk sediment elemental analysis method for determining multiple elemental concentrations was thus developed for future high-resolution paleoceanographic reconstructions in Chapter 2. To identify appropriate redox proxies minimizing post-depositional overprints, we applied Fe speciation to quantify reactive Fe towards sulfide. The results were cross-validated using magnetic analyses that characterize preserved Fe phases. We confirmed in Chapter 3 that instantaneous depositional events (e.g., flood and turbidite layers) could initiate post-depositional pyrite formation, and result in ‘false-positive’ sulfidic (no DO and HS- present) interpretations, compromising redox reconstructions. In contrast, redox-sensitive trace metals (Re, Mo, and U) seem to be unaffected by instantaneous depositional events. A post-Industrial oxygenation history was then constructed from redox-sensitive trace metal records from the Santa Barbara Basin (SBB), Southern California in Chapter 4. We demonstrated that the gradually intensified Southern California OMZ since the 20th century is associated with the anthropogenic warming. To further explore the natural variability on multi-centennial to millennial timescales, I explored a Common Era core (~2 – 5 year resolution) in SBB. Bulk sedimentary N isotopic composition was reconstructed in Chapter 5, which revealed competing tropical and subarctic waters that transport nitrate to Southern California. We confirmed more tropical water influences during the Medieval Climate Anomaly (MCA, 1000 – 1100 CE). However, stronger connections with the subarctic water transport during the Little Ice Age (LIA, 1670 – 1840 CE) coincided with the strongest Aleutian Low (AL), suggesting nitrogen cycling responses to atmospheric forcing. In Chapter 6, we generated the highest-resolution DO record (4 – 9 years) to date in the North Pacific using the same core, which revealed the lowest DO during the MCA corresponding to the warmest pre-Industrial interval in the Common Era. The natural OMZ deoxygenation rates were significantly faster than the post-Industrial reconstruction in Chapter 4, suggesting that the post-Industrial OMZ intensification is not unprecedented. Additionally, a low-oxygen interval during the cold LIA (1550 – 1750 CE) was inconsistent with either climate or productivity. We suggest that this low-oxygen interval was due to less ventilated North Pacific Intermediate Water (NPIW) that propagates to the east. A comparison of proxies (sea ice, oxygenation, and AL proxies) and the Last Millennium Reanalysis corroborates that a weaker/westward AL and weakened Siberian High resulted in weaker wind stress and prevailing easterlies over the Sea of Okhotsk, reducing the sea ice production and NPIW ventilation despite the relatively cold period. A similar oxygenation response to atmospheric teleconnections was indicated for the Holocene in Chapter 7, with much lower DO in the early- to mid-Holocene (~6 ka before present) than the post-Industrial. A state-of-the-art model corroborates basin-wide low DO responses due to NPIW oxygenation changes that are associated with reduced sea ice brine rejection tying to a weakened AL under mid-Holocene orbital forcing. These results demonstrate a nuanced mid-depth ventilation and OMZ response to climate change in the Holocene, and underline the role of atmospheric circulation in controlling natural OMZ variations. The dissertation thus calls for additional high-resolution reconstructions to constrain the natural OMZ variability, especially in the background of anthropogenic climate change.

Southern California has a Mediterranean climate characterized by wet winters and dry summers. With both significant seasonal precipitation variability and unusually large interannual variance relative to the rest of the US, Southern California presents a huge challenge to water resource management as state water demands continue to grow. In this dissertation, I use multiple lines of evidence, including precipitation reconstructions, climate model outputs, and reconstructed vegetation, to explore the causes of hydroclimate change in this region. This understanding is critical for regional climate projections, water resource management, and forest ecosystems sustainability. A robust 9000-year high-resolution Bayesian age model was generated using 89 accelerator mass spectrometric 14C dates for laminated marine sediments from central Santa Barbara Basin (SBB), California. Multiple flood (extreme precipitation events with an average return interval of ~100 years) and turbidite (earthquake induced slope failures with an average return interval of ~500 years) layers were identified. A master stratigraphy for the Holocene was created using these layers and correlated multiple marine sediment cores from SBB to place all published SBB proxy paleoclimate records into the new chronology. A sub-annually resolved Southern California precipitation record was reconstructed using ITRAX scanning X-ray fluorescence titanium counts from the same laminated sediment sequence in SBB. Instrumental precipitation data from the 20th and 21st centuries was analyzed to demonstrate that Southern California precipitation is significantly correlated with El Niño Southern Oscillation (ENSO) on interannual timescales via an ENSO teleconnection between the tropical Pacific and North America. The Ti-based precipitation reconstruction over the Common Era demonstrates the ENSO teleconnection is modulated by both tropical forcing and mid-latitude atmospheric pressure systems (the Aleutian Low). Strong interannual precipitation variability occurred when greater ENSO variance was observed in the tropical Pacific and when the Aleutian Low deepens in the northeast Pacific (e.g. 1370-1540 CE). Interannual precipitation was weak when either ENSO variance is reduced (700-900 CE) or the ENSO teleconnection was muted by a weakening of the AL (1540-1680 CE). The sub-annual SBB precipitation reconstruction was extended back through the Holocene (9,000 years) to demonstrate that interannual precipitation variability increased significantly during late Holocene (after 4,500 years ago) when the Intertropical Convergence Zone (ITCZ) migrated southward and the Aleutian Low strengthened. The influence of ITCZ and Aleutian Low position was examined using model simulation outputs: a southward shifted ITCZ weakens across-equatorial trade wind, potentially enhancing tropical Pacific ENSO variability and strengthening the Aleutian Low in the North Pacific. Such atmospheric circulation changes lead to a stronger ENSO teleconnection with Southern California and thus greater interannual precipitation variability in the region. A new multidecadal-resolution pollen record in SBB was compared to regional precipitation reconstructions to explore the vegetation response to different aspects of hydroclimate change including interannual precipitation variability. The drought-adapted endemic vegetation appears insensitive to both interannual precipitation variability and extreme precipitation events, displaying only a subtle long-term response to orbital-forced seasonal insolation variance over the Holocene. However, prolonged or severe droughts may have a minor impact on the distribution of the coastal mosaic oak woodland/ chaparral/ sage scrub communities in this region on multidecadal to centennial timescales.

While neighborhood upgrading has transformed into a widespread and globalized process, debates about it have long been heated, especially on its definitions and its consequences. Often times, the dialogue about neighborhood upgrading is either gentrified or not gentrified, either displaced or not displaced, and either beneficial or harmful. However, this sort of dichotomic understanding of neighborhood upgrading has neglected the complexity of the process and assumed a universal understanding of the term “gentrification”, while no consensus has been reached so far on a precise definition of it. The main aim of this dissertation is therefore to understand the nuances among different types of neighborhood upgrading and the multi-dimensional impacts of such processes on different stakeholders.This dissertation research discusses neighborhood changes primarily in three different aspects: the various forms of neighborhood upgrading, impacts of neighborhood upgrading on local residents, and the association between neighborhood upgrading and business dynamics. Each of the three aspect is investigated in a separate study. This dissertation debunks some of the standard stereotyped understanding of neighborhood upgrading. The results of this dissertation present that some degree of neighborhood upgrading can occur without massive racial changes, and potential “gentrifiers” may not be limited to one particular race/ethnicity. Instead of being solely harmful to businesses, neighborhood upgrading can bring more opportunities to some business sectors. Through exploring the neighborhood change patterns in Los Angeles and other large cities in the US during the 2000s, this dissertation draws a more comprehensive picture for scholars, policy makers and urban planners to better understand the process.

A collection of short fiction set in and around Southern California.

In this dissertation, I study two fundamental topics in seismology, tidal triggering of earthquakes and attenuation and scattering structure. Studies of tidal triggering help constrain earthquake nucleation models and relate to earthquake predicability and forecasting. Resolvingattenuation and scattering behavior can provide more physically realistic models for strong ground motion prediction equations (GMPEs) and improve our understanding of the physical properties of rocks in the lithosphere. Chapter 1 is an introduction, providing background and motivation for each of the following chapters. Chapters 2 & 3 focus on the topic of tidal triggering of earthquakes. Chapter 2 studies tidal triggering in the central Japan region using M>3 earthquakes and finds no clear evidence for tidal triggering. Chapter 3 analyzes seismicity in the Coso region of California and finds strong tidal triggering but an absence of remote triggering at the Coso geothermal field, constraining earthquake triggering sensitivities at different time scales of stress perturbations. Chapters 4-6 study the inelastic properties of the crust and upper mantle in southern California using both coda and direct-wave observations. Chapter 4 stacks coda envelope functions across southern California and synthesizes them using a two-layer model, composed of a shallow crustallayer with strong wide-angle scattering and high P and S intrinsic attenuation and a deeper layer with weaker scattering and lower intrinsic attenuation. Chapter 5 describes improvements to the conventional coda-Q method to solve for coda attenuation, site amplification and source radiated energy simultaneously. Chapter 6 models focal-sphere-dependent S/P amplitudes assuming awhole-space intrinsic and scattering attenuation model around the San Bernardino region.

Within the last 30 million years, the Southern California plate boundary has transitioned from a region of plate collision and subduction to a right-lateral translational boundary. This transition created many of the geologic features that are observed today along the Inner California Borderlands (ICB), including the Western Transverse Range Province (WTR). The WTR has long been considered a large coherent block (~200 by 100 km) that underwent 90-100 degrees of clockwise rotation in the early Neogene as a result of right-lateral transform motion along the margin in a process characterized as “book-shelf” faulting. Directional paleomagnetic data have been employed to support the hypothesis of coherent rotation of ‘books’, here referred to as a `large coherent block’. As the data collected in this region vary in quality, age, and locality, we set out to test how well the data support the large coherent block rotation hypothesis of the WTR when viewed as a composite. If the large coherent block rotation model is correct, it predicts the paleomagnetic directions of the same age within the WTR should record the same amount of rotation. To test this, we have compiled a large set of directional paleomagnetic data from relevant published papers, updating the age constraints to a consistent time scale where possible. By re-examining directional paleomagnetic data from same-age rocks within the WTR, our compilation shows different amounts of rotation across the WTR from formations that are similar in age. The directional paleomagnetic data are therefore inconsistent with the prediction of a large coherent block rotation model. We propose an alternative model for the deformation of the WTR, one that is consistent with paleomagnetic data from the region. In our model, rather than a single large block rotating coherently, many micro-plates that range from kilometers to tens of kilometers rotated individually, accommodating numerous right-lateral fault displacement. Our analog for the deformation of the WTR is a garnet schist, where the “garnets” are the microplates rotated by bounding right-lateral shear zones.

The purpose of this qualitative phenomenological study was to describe the lived experience of priapism among male adolescents with sickle cell disease (SCD). A painful genetic disorder with no cure, SCD severely impacts the lives of patients, as well as their families and friends. Priapism is one of the complications of SCD and involves persistent and painful penile erections. The review of literature established a gap in researchers’ understanding of the lived experience of priapism among male adolescents with SCD. This study aimed to bridge that gap. Using a convenience sampling method, 7 adolescent males between the ages of 16 and 19 with a history of SCD and the complication of priapism were selected for the study. A phenomenological approach guided this study. Qualitative data was drawn from semistructured face-to-face interviews using an interview protocol with 22 open-ended questions. Data were analyzed by transcribing audio tapes and coding information from transcripts into themes, patterns, and categories. Themes were identified that reflected the central, recurrent ideas that emerged from the participant responses. The results of this research study demonstrate the significance of various themes associated with living with SCD and the complication of priapism for male adolescents, including: (a) Concerns with sexual performance, stigma, and associated psychological effects; (b) Quality of life and support systems; (c) Experiences with medical care; and (d) Knowledge of the condition and advice for others. The findings of this study confirm some previous literature while lending further insights that help expand researchers’ knowledge regarding the lived experiences of male adolescents with SCD and the complication of priapism. Based on these findings, the implications for practice and opportunities for future research are broad and varied. It is imperative to develop awareness trainings or educational programs to better inform medical practitioners and SCD patients about the complication of priapism. Further research is needed to gain a better understanding of the prevalence of priapism in the SCD male adolescent population. Future studies should analyze whether this complication is hereditary, lifestyle-related, or can affect anyone. Keywords: priapism, male adolescent, sickle cell disease

Come into a journey where you will examine the nature of Evelyn Contreras work through the lens of Los Angeles. You will be guided by BETA-KAR system which will take you to each portal. BETA-KAR will inform you of the work and keep you safe. Please enjoy the ride.

This study addresses the shortcomings in the literature by collecting primary, farm-level data via a questionnaire for several productive regions of California that are often overlooked in agricultural analyses. Farm-level analyses help develop bottom-up incentives for adapting to climate change and addressing water scarcity. Because it is the localized climate directly observed by the economic agent, microclimate is more likely to impact production decisions than sub-regional averages. I study the impacts of change in microclimate on agricultural productivity in desert and southern California regions while controlling fro other micro-level effects such as grower, farm, and water source characteristics. I also analyze the extent to which microclimate influences the adoption of two important water management strategies: soil moisture and salinity monitoring. In addition, I analyze microclimatic impacts on productivity and land sales at the parcel-level.

Southern California is highly susceptible to hazards related to seismic activity and storms linked with El Niños and Atmospheric Rivers. These hazards are capable of incurring flooding, debris flow, coastal inundation, and rapid coastal erosion. Although much work has been done using lacustrine and deep marine sediment records to reconstruct the frequency of these past events, coastal records from lagoons and estuaries are less well documented. Here we present detailed sedimentologic and geochemical analysis of sediment cores, constrained by radiocarbon dates, from two estuarine/lagoon systems from coastal Southern California, Campus Lagoon and Las Salinas Lagoon. Our results record multiple occurrences of marine inundation thought to record storms of similar or greater magnitude as the catastrophic winter storms of 1861-1862. At least three of these events occurred pre 149 calibrated years before present (CYBP), one between 149 and 397 ± 22, two between 397 ± 22 and 617 ± 105 CYBP, and three between 1050 ± 200 and 3400 ±190 CYBP. These events establish a historic recurrence interval of ~660 years, and a post 2000 CYBP interval of 320 years, comparable to other California records. However, two of these pre-1 ka events may be the result of tsunami washover rather than storm washover as they correlate to large magnitude seismic earthquakes along the Pitas Point fault at 1050 ± 200 and 2250 ± 300 CYBP. A simultaneous environmental shift from an open lagoon to barrier-lagoon is observed in both lagoons at 4300 ± 250 CYBP that is interpreted to represent the onset of beach progradation in the Santa Barbara Channel in response to slowing sea-level rise.

Marine protected areas (MPAs) are areas aimed at protecting natural and cultural resources that are often proposed as a way to alleviate the effects of overfishing on populations of targeted species; these areas have varying degrees of fishing and recreational use restrictions. In order to assess MPA efficacy, it is important to determine the mechanisms by which the presence of MPAs affect reproductive output within and potentially even beyond their boundaries. I attempted to address this through studying the responses of rockfish (Sebastes spp.) larval abundances to the presence of the Cowcod Conservation Areas (CCAs) located within the Southern California Bight region. Rockfish larvae were collected from mesozooplankton samples obtained during winter survey cruises by the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program and identified by sequencing the cytochrome b gene. I constructed time-series of rockfish larval abundances within the Southern California Bight from 1998 to 2013. I found that, not only have delta mean larval abundances of multiple rockfish species increased throughout the period, three historically-targeted species’ delta mean larval abundances—Bank Rockfish (S. rufus), Speckled Rockfish (S. ovalis), and Olive Rockfish (S. serranoides)—increased at a greater rate within the CCAs compared to locations with similar environmental parameters outside of the CCAs. This is the first decadal-scale study that explicitly demonstrates an increase in reproductive output from an MPA in the form of increased larval 2 abundances, thus contributing crucial information to the understanding of MPA efficacy. Additionally, the dataset created during this study will become the basis for several future studies that will further elucidate the spatiotemporal dynamics of rockfish larvae within CCAs and in the Southern California Bight region as a whole. These studies will further contribute to understanding the efficacy of the CCAs in their facilitation of rockfish species recovery, as well as provide important information for rockfish fisheries management in the region.

Implications of multiple climate drivers for sea urchins were investigated across a spectrum of biological organization ranging from the urchin guild scale, to individual life history traits, to the geochemistry, material properties and porosity of sea urchin calcium carbonate skeletal tests. Using pink fragile sea urchins (Strongylocentrotus fragilis) on the southern California upwelling margin as a model species, links between biological traits and environmental parameters in nature across multiple spatial and temporal scales revealed correlations with dissolved oxygen (DO), pH, and temperature. Temporal trends in sea urchin populations assessed from trawl surveys conducted in southern California over the last 20 years (1994-2013) revealed changes in deep-sea urchin densities and depth distributions that coincide with trends in DO and pH on multidecadal and interdecadal (El Niño Southern Oscillation) time scales. The shallower urchin species (Lytechinus pictus) decreased in density in the upper 200 m by 80%, and the deeper S. fragilis increased in density by ~300%, providing the first evidence of habitat compression and expansion in sea urchin populations associated with secular and interdecadal variability in DO and pH. In this context, marketable food quality properties of the roe were compared between S. fragilis and the currently fished California red urchin, Mesocentrotus franciscanus, to assess the feasibility of developing a climate change-tolerant future S. fragilis trap fishery. Although roe color, texture, and resilience were similar between the two species, smaller and softer S. fragilis roe suggest it may only supplement, but not replace M. franciscanus in future fisheries. In comparisons across natural margin depth and climate gradients from 100-1100 m, S. fragilis exhibited reduced gonad production, smaller, weaker and more porous calcified tests in the Oxygen Minimum Zone (DO < 22 µmol kg-1) and pH Minimum Zone (in situ pHTotal

Policy, management, and restoration practices focused on the federally endangered southern California steelhead (Oncorhyncus mykiss) were reviewed, tested, and compiled to provide opportunities to capitalize on already existing tools for steelhead recovery and other protected species inhabiting southern California coastal watersheds. Review of the Similarity of Appearance Clause, a rarely used portion of the Endangered Species Act, could provide southern steelhead’s landlocked resident form (native rainbow trout) with greater protection from take based on the difficulty in differentiating between the two life history stages. Southern steelhead meets inclusion criteria set forth by the act, but more importantly fills the need for a precautionary approach in managing a highly endangered species. Despite being a priority recovery action small dam removal is still subject to environmental review, but recent streamlining efforts through programmatic permitting could reduce the burden on restoration partners. In the absence of examples of small dam removal monitoring data National Marine Fisheries Service programmatic biological opinion for southern California was forced to implement precautionary thresholds on the amount of impounded sediment to avoid prolonged effects of sediment bleeding and loss of downstream habitat quality that may result under extended drought conditions. This research utilized low-cost, longstanding techniques to meet the monitoring requirements set forth in the programmatic opinion and added six small dam removal cases to support the finding of limited effects by impounded sediment on habitat quality downstream of dam removal sites. This study highlights the greater influence of upstream watershed inputs (land-use practices, roads, fires, etc.) on habitat quality rather than small dam removal impacts. Consideration of impacts and drivers on a watershed-wide scale (headwaters to ocean) is important for restoration targeting anadromous species like southern steelhead. A comparison of stream and wetland restoration issues identified common problems: climate change and process organization. Differences in permitting issues for streams and design concerns for wetlands are discussed in relation to the scale and geographical extent of habitat type in southern California. These are just a few examples of how rethinking lessons learned and reexamining already existing tools could aid in recovery of endangered species and maximize restoration dollars.

When wildfires threaten human populations, untimely or late evacuation can mean the difference between life and death. In the fire prone regions of the world, last minute evacuations have been responsible for hundreds of deaths and thousands of injuries. In Southern California, where fire season persists for the majority of the year and where human populations continue to expand into lands conducive to wildfire, emergency management officials commonly issue evacuation orders to initiate protective action behavior for those threatened. While early evacuation generally provides the safest course of action for people in the path of wildfire, past research has shown that for a variety of environmental hazards, humans do not always immediately heed official warnings, and delay evacuating. This cross-sectional study uses a mixed-mode survey design and survival analysis to investigate the evacuation timing behavior of residents drawn from a simple random sample of Southern California households (n=221) during the 2016 Blue Cut fire in San Bernardino County, California. Findings from these analyses indicate that only half of those receiving a mandatory evacuation order evacuated because of the Blue Cut fire. Residents with past evacuation experience were almost twice as likely to evacuate compared to residents without prior experience. Gender and length of residence were found to be associated with shorter evacuation times and higher evacuation rates, with women and short-term residents more likely to evacuate compared to men and longer-term residents. The findings from this study suggest that if emergency managers and local public agencies can get wildland residents to evacuate when an evacuation order is issued, they may have future success getting them to evacuate during subsequent wildfire evacuation events. However, this study also identifies a significant number of residents who are resistant to evacuation. Addressing the concerns of this group may help increase the speed and rate of future evacuation events.

The acoustic repertoire of the Northeast Pacific population of blue whales (Balaenoptera musculus) consists of three different sounds: A, B, and D calls. The pulsed A and tonal B calls can be produced singularly or in phrases or songs, while downswept D calls are only produced as singular calls. Although these sounds have been well described, the behavioral context of sound production is poorly understood. To investigate spatial and temporal variability in blue whale call and song usage off southern California, passive acoustic data collected from four High-Frequency Acoustic Recording Packages (HARPs) were analyzed. The acoustic and dive profile data collected through tags deployed on blue whales were also analyzed to describe the behavioral context of sound production. Singular call and phrase production rates were calculated to assess variability in sound type abundances on different spatial, temporal and behavioral scales. Distinct differences in song type preference were apparent, with offshore sites featuring songs comprised of multiple sequential B units following a single A, while inshore, A and B units alternated. Most blue whale sounds were produced during the summer and fall. The majority of all sounds produced by tagged blue whales occurred during non-lunging dives at shallow depths (less than 30 m). Song production was associated with shallow, non-lunging dives, while singular calls often occurred during lunging dives or bouts of surface behavior. The observed differences in blue whale acoustic behavior off southern California will aid in the development of context specific rates for future models of density estimation.

Fin whales (Balaenoptera physalus) produce a stereotyped low frequency call (15-30 Hz) that can be detected at great range and is considered song when produced in a repeated pattern. These calls, referred to as 20 Hz calls, were localized and animals were tracked using a kilometer-scale array of four passive acoustic recorders deployed at approximately 800m depth, northwest of San Clemente Island in the Southern California Bight. A total of 4969 calls were localized over four continuous weeks during late fall of 2007. The average estimated source level for the localized calls was 190.9 ± 7.4 dB peak-to-peak re 1µPa2 at 1m. The majority of the calls in these data were in the form of a doublet song pattern, with average inter-pulse intervals (IPI) 13s and 18s. The tracks were the first to be recorded for singing fin whales transiting alone using passive acoustic monitoring. Acoustic tracking of fin whales provides insight into the ecology and behavior of the species. Estimating call source levels help future predictions of how these whales are impacted by anthropogenic noise. Call source level, along with calling behavior, provide important parameters required for population density estimation. Furthermore, studying fin whale song patterns may aid in distinguishing different subpopulations.

Introduction: Vape shops have grown in popularity among adults and youth. The increased popularity of electronic cigarettes has triggered many new businesses to open within the last three years to sell electronic cigarettes devices, flavor liquids and provide a place for lounging. High levels of ultrafine particles (UFP) are generated when active vaping is occurring. Objectives: 1. Quantify and understand the spatial distribution of ultrafine particles in vape shops. 2. Identify factors that generate elevated levels of ultrafine particle concentrations.Methods: Two vape shops in Southern California were recruited to participate in the study. There were six testing days for vape shop A and four testing days for vape shop B. Ultrafine particles were collected using two TSI Condensation Particle Counters. Carbon dioxide, relative humidity and temperature were also measured using a TSI Q-Trak Plus. CPC A was placed in a high activity area and was kept there for subsequent sessions. CPC B rotated around the store and outside. The Q-Trak was placed with CPC A during the sampling sessions. The air exchange rate (AER) was calculated using one overnight CO2 trend data using the TSI Q-trak. Results: A temporal profile of UFP showed that high spikes of UFP were observed during vaping. The CPC placed in a low activity area, showed similar up and down fluctuations of UFP as shown in CPC A, even when no activity was occurring near the instrument. The UFP increased significantly when 1-2 and 3+ individuals were vaping compared to when no vaping was occurring. The UFP differed significantly (P

In Southern California, from 1870 to 1950, two sectors of the economy interacted to produce major changes in the region. Citrus agriculture and transcontinental railroads defined the economy, landscape, labor, and culture of the Southland. As railroads linked Southern California to the far corners of North America in the 1870s and 1880s, they ended centuries of isolation. They made it possible for growers to ship their goods to the Midwest and Atlantic Coast. Almost simultaneously, the citrus industry expanded in Southern California. Introduced by Spanish friars during the 1800s, orange and lemon growing boomed in the 1870s thanks to the importation of the Washington Navel orange from Brazil. Spreading out from the epicenter of Riverside, the orange empire incorporated portions of Riverside, San Bernardino, Los Angeles, Orange, Ventura, Santa Barbara, San Diego, and Imperial Counties. Railroad companies competed to corner the trafficking of citrus fruits from California, resulting in an extensive network of rails across this orange empire. Although high startup costs were associated with the establishment of an orange grove, lucrative returns, facilitated by railroad connections to markets, led to prosperity in Southern California from the 1890s to the 1950s.Numerous developments accompanied the intertwined activities of the orange and railroad industries. Technical innovations, such as the invention of refrigerator cars and advanced packing machinery to preserve oranges during transit, facilitated the growth of industry. New cities, devoted almost entirely to citrus cultivation, appeared along the railroad tracks. Railroaders and orange growers worked together to irrigate the parched Southland, and, when necessary, to limit the effects of floods, and promoted the spread of electricity. However, they also brought far more ambivalent consequences. Laborers, often drawn from ethnic minorities, suffered the constant threat of bodily harm and low wages. From the Pullman strike of 1896 to the guerilla war of 1936 in Orange County, railroads and grove owners quashed attempts at organized labor. Railroad and citrus boosters also promoted California as paradise, but minimized the roles of laborers by stereotyping them in advertisements and publications. Despite their gradual decline in the 1950s, these twin industries interacted in a variety of ways, creatively and destructively, overlapping to shape the history of Southern California.

Global warming, caused by the increase of CO2 emissions, has increased frequency and intensity of climate extremes. Extreme events have large impacts on the terrestrial ecosystem carbon. Therefore, it is fundamental to investigate the subterrestrial processes of producing carbon dioxide. Carbon dioxide flux is affiliated with heterotroph and autotroph and they are influenced by abiotic and biotic factors. In this study we investigated the soil moisture-soil temperature-soil respiration relationships on bare soil and the impact of hot days and warm spells on soil respiration. Measurements were taken from February to June 2016 in Southern California (33° 39ʹ32.7ʺ N, 117° 50ʹ55.9ʺ W) where several hot spells occurred. Bias corrected maximum air temperature was used to calculate the warm spell threshold. Land and atmospheric parameters respond with dealt to soil respiration. Association metrics were employed to explore the relationship between soil respiration and both collected and time-lagged data. Soil moisture and soil temperature were the two most important factors affecting soil respiration whereas soil temperature was the ascendant factor. The results show that soil with temperatures ranging from 20 to 25 °C displays the highest average CO2 flux value (~ 1.12 μmol CO2 m-2 s-1). By deviating from the soil temperature range of 20 to 25 °C the average CO2 flux decreases. Soil respiration increases by around 50% when soil temperature increases from 15 to 20 °C to 20 to 25 °C and decreases by 48% by deviating from the soil temperature range of 20 to 25 °C to 25 to 30 °C. Soil respiration decreased when both soil moisture and soil temperature were out of the optimum range (0.225 to 0.250 m3/m3 and 20 to 25 °C, respectively) of microorganism. In other words, soil respiration decreased when soil moisture and or soil temperature were too low or too high. Hot days or warm spells intensified soil temperature, leading to low soil respiration compared to non-hot days or warm spells. A net flux of 0.60 grams of CO2 per m-2 was released during the study period.

Globally, the rate of emergence of infectious diseases has increased significantly over time. Vector-borne diseases in particular present one of the biggest threats to public health globally. Many of these diseases are zoonotic in nature, meaning they cycle in animal populations but can spillover to infect humans. As such, risk to humans of acquiring a zoonotic disease depends in large part on the distribution and abundance of the reservoir hosts, the species of animals that the pathogen naturally infects, as well as of the vector species. The ecology of many reservoir hosts and vectors is rapidly changing due to ongoing environmental change, which will fundamentally alter human disease risk in the future. To understand how disease risk may be forecasted to change requires an understanding of the drivers of the distribution and abundance of pathogens, disease vectors and reservoir hosts.This research uses Lyme disease in California as a model system to understand the drivers of zoonotic disease risk on a rapidly changing planet, particularly for vector-borne diseases. Specifically, it investigates the following questions: 1) are there latitudinal differences in the seasonal activity patterns of the primary tick vector, Ixodes pacificus, in California, and might these differences be driven by climate? 2) What abiotic and environmental factors drive tick abundance and infection prevalence with the causative agent of Lyme disease, Borrelia burgdorferi sensu stricto, in southern California? 3) What are the effects of large-scale, intense ecological disturbances, namely wildfire, on the ecology of Lyme disease in the far western US? To address these questions, I use a combination of field, laboratory and statistical methods including field collection of samples (ticks and tissue samples from host animals), DNA extraction and polymerase chain reaction (PCR) in the laboratory for analysis of infection, and statistical and GIS-based analysis of field-derived and public data sets. I find that tick vector activity patterns in southern California are highly truncated, and tick density is significantly lower than in northern California where human Lyme disease incidence is higher. This suggests much lower tick-borne disease risk in southern California, which I broadly attribute to the hotter, drier climate in this region. This has implications for reduced tick-borne disease risk under future climate change, in contrast with the predictions made for numerous other emerging diseases (Chapter 1). Additionally, I identify dense oak woodlands as the highest risk habitats for I. pacificus tick encounter in southern California. I also find densities of small vertebrate hosts to be significant predictors of tick abundance, though found a shift in the relative importance of host availability and habitat characteristics in predicting juvenile tick abundance as California’s historic drought intensified. This finding suggests that habitat providing suitable microclimates for tick survivorship became centrally important to patterns of abundance in the face of adverse abiotic conditions. This further suggests that predicted climate change in California may act as an important limiting factor on I. pacificus populations. And, despite the low risk of human Lyme disease infection posed by I. pacificus in southern California, comparatively high rates of infection were found in other tick species, suggesting that enzootic transmission of tick-borne borreliae may be more common in southern California than previously suspected (Chapter 2).Finally, I find that wildfire disturbance, which is projected to become more severe under climate change, initially increases tick-borne disease risk in the year following fire, with this effect reversing in subsequent years. Tick abundance was elevated in plots sampled within the perimeter of a recent wildfire in Santa Barbara County, California in the year following the fire, though declined precipitously in following years. Also notable was the finding that populations of one of the primary reservoir hosts for the Lyme bacteria, dusky-footed woodrats (Neotoma fuscipes), were eliminated within the perimeter of the fire. In contrast, populations of western fence lizards (Sceloporus occidentalis), considered to be “non-competent hosts” for the bacteria because they cleanse feeding ticks of infection and do not carry the pathogen, were unaffected by the wildfire. Taken together with significantly reduced tick populations within the fire perimeter following the fire, this evidence suggests that wildfire disturbance may ultimately reduce tick-borne disease risk for multiple years following wildfire in California (Chapter 3).Ongoing environmental change has already led to disease emergence across the globe, with consequences for human health. Further, the way in which environmental change is expected to impact the ecology of infectious diseases is challenging to predict and poorly understood for many disease systems. My dissertation research informs some of these key gaps in our understanding of tick-borne disease in the western US under environmental change.

Wildfire return intervals are expected to decrease in shrubland communities across southern California due to increasing anthropogenic fire ignitions and climate change. These shortened fire intervals may initiate a positive feedback, placing native chaparral species at risk of replacement by alien annual grasses. This shift is predicted because many chaparral species require multiple years to recover from a wildfire disturbance (i.e., to replenish the seedbank or to replenish underground carbohydrate reserves) and if a second wildfire occurs in quick succession, these species may experience a severe population decline or even extirpation as new seedlings or young resprouts are killed. After generating a wildfire occurrence map, I selected twelve polygons that experienced two wildfires within five years to evaluate vegetation change following a short-interval fire. All polygons were located in Ventura or Los Angeles County, California and spanned a temporal range from 1956 to 2003. These polygons were then compared to adjacent polygons that experienced only one wildfire within the same five-year period. In order to capture prefire vegetation conditions, historical aerial photographs (HAPs) were selected as-close-to before the first wildfire as possible. In order to capture the maximum postfire growth, HAPs were chosen to be no less than six years following the second wildfire. Prefire and postfire images were georectified and used to calculate ground cover using five community types: chaparral, alien annual grass, sage scrub, tree or bare ground/exposed rock. To determine the role of regional moisture gradients and environmental conditions in predicting vegetation change I investigated aspect, location in relation to the Santa Ana wind corridors, distance from the coast, time since fire, and prefire cover values as potential predictors of the strength and direction of vegetation responses. Results showed no significant differences in vegetation cover from short interval wildfires compared to adjacent single wildfires. Prefire vegetation cover was highly correlated with postfire cover. Chaparral and sage scrub cover showed strong trends in relation to the time since fire, especially following a single wildfire: positive vegetation change for chaparral and negative vegetation change for sage scrub. Location in relation to the Santa Ana wind corridors and distance from the coast were not found to be significant factors of vegetation change. By contrast, ‘aspect’ correlated with significant differences in vegetation cover, regardless of wildfire history, for chaparral and sage scrub communities: chaparral cover declined and sage scrub cover increased after wildfire on north, but not south, aspects. This study did not find evidence of chaparral loss strictly as a result of a single short interval wildfire. I propose that additional factors, such as aspect and initial community cover (extent), may be equally or more important than a single short interval fire when predicting vegetation changes following wildfire in southern California.

Foraminiferal assemblages are useful for producing high resolution sea-level curves, interpreting ancient marine and coastal sediments, and reconstructing past climates. However, their use for these purposes is dependent on knowing the environmental controls on their distribution, which varies regionally. In this study, I document the environmental variables controlling the distribution of foraminifera in Carpintaria Slough in southern California. The foraminiferal assemblages were determined at 29 sample locations within the marsh. Assemblages were complimented by measurements of elevation, pore-water salinity, pore-water pH, and grain size. Total organic carbon was also measured in 16 of these samples.Three distinct biofacies were identified using Q-mode cluster analysis. Four species of foraminifera were shown to have statistically different mean abundances between the three biofacies zones, through the implementation of one-way analysis of variance tests (ANOVA). Zone 1 is defined by mean abundances of Miliammina fusca comprising between 30 and 60% of the entire sample. Zone 2 is defined by mean abundances of Elphidium excavatum comprising between 0 and 2% of any sample, and Ammonia parkinsonian comprising between 2 and 4% of any sample. Zone 3 is defined by a mean abundance of Balticammina pseudomacscerens comprising between 45 and 50% of any sample.Correlation analysis, principle component analysis, and ordinary least squares linear regressions suggest that the distributions of foraminiferal species in Carpinteria Slough are linked to the environmental variables of elevation and salinity. Principle component analysis demonstrates that the percent of total variance in assemblage data is explained by elevation (33.68%), salinity (16.52%), pH (12.49%), and median grain size (12.42%). Although, the link between environmental variables and foraminiferal assemblages lacks definitive correlations, a final ANOVA, based upon elevation, is able to separate the foraminiferal data into two elevation zones. Zone A consists of all elevations below 0.83m and Zone B consists of all elevations above 0.83m. Therefore, foraminifera from southern California marshes provide limits to the refining of past relative sea-levels at the sub-meter scale.

Long sediment records from offshore and terrestrial basins in California show a history of vegetation and climatic change since the last interglacial (130,000 years BP). Vegetation sensitive to temperature and hydroclimatic change tended to be basin-specific, though the expansion of shrubs and herbs universally signalled arid conditions, and landscpe conversion to steppe. Multi-proxy analyses were conducted on two cores from the Big Bear Valley in the San Bernardino Mountains to reconstruct a 125,000-year history for alpine southern California, at the transition between mediterranean alpine forest and Mojave desert. Age control was based upon radiocarbon and luminescence dating. Loss-on-ignition, magnetic susceptibility, grain size, x-ray fluorescence, pollen, biogenic silica, and charcoal analyses showed that the paleoclimate of the San Bernardino Mountains was highly subject to globally pervasive forcing mechanisms that register in northern hemispheric oceans. Primary productivity in Baldwin Lake during most of its history showed a strong correlation to historic fluctuations in local summer solar radiation values. Rapid organic perturbations in the Baldwin Lake core were coeval with Dansgaard-Oeschger (D-O) events from the North Atlantic, which were evident in records from the Santa Barbara Basin. The predominant vegetation signal at Baldwin Lake was one of temperate conifer forest expansion during moist conditions, and contraction during dry conditions. This expansion and contraction was paced with summer insolation fluctuations during Marine Isotope Stage 5 (110,000 – 71,000 years BP), before a regime change towards more rapid, shorter-lived hydroclimate extremes. Wildfire is an important agent of landscape change throughout the Valley’s history, with two hiatuses during cold and moist conditions from 25,000 – 14,000 years BP, and arid conditions 7,000 – 3,000 years BP. Taken together, this multi-proxy dataset suggests that paleoclimatic changes in alpine southern California have been highly sensitive to three climate drivers: 1) shifts in local summer insolation, 2) rapid warming in the North Atlantic, and 3) changes in the strength of the California Current. The record also showed a wide range of possible moisture states in southern California’s past that vary from present conditions, including multi-millennial states of long-term aridity and pre-glacial deep lake conditions.

For exposure to urban air pollution, disparities by race, ethnicity, and socioeconomic class are well documented, but there are few methods or tools to evaluate or quantify the justice and equality effects of emission-reduction options. That gap hampers the advancement and implementation of rigorous policies to address environmental justice. Here, I employ state-of-the-science air dispersion modeling for diesel-generated fine particulate matter in Southern California to estimate how location-based changes in fine particle emissions would impact four goals: health impact, exposure efficiency, exposure equality, and exposure justice. My results explore how spatially targeted reductions may improve environmental justice and equality. Results indicate potential trade-offs (e.g., an increase in equality but reduction in justice) as well as opportunities for “win-wins”: for a region I identify, a 2.6% emission-reduction would benefit overall average exposure, exposure inequality, and exposure injustice by 5%, 6%, and 18%, respectively. As another example, rerouting trucks to avoid hot spots of exposure disparity could improve exposure justice up to 67% and reduce the potential exposure of the truck emissions by 17%. Understanding the spatial patterns of environmental justice, and the connections to spatial patterns in emissions, may highlight how targeted emission-reduction can help maximize efficiency and justice-based goals.

Southern Californian wildfires can influence climate in a variety of ways, including changes in surface albedo, emission of greenhouse gases and aerosols, and the production of tropospheric ozone. Ecosystem post-fire recovery plays a key role in determining the strength, duration, and relative importance of these climate forcing agents. Southern California's ecosystems vary markedly with topography, creating sharp transitions with elevation, aspect, and slope. Little is known about the ways topography influences ecosystem properties and function, particularly in the context of post-fire recovery. We combined images from the USGS satellite Landsat 5 with flux tower measurements to analyze pre- and post-fire albedo and carbon exchanged by Southern California's ecosystems in the Santa Ana Mountains. We reduced the sources of external variability in Landsat images using several correction methods for topographic and bidirectional effects. We used time series of corrected images to infer the Net Ecosystem Exchange and surface albedo, and calculated the radiative forcing due to CO2 emissions and albedo changes. We analyzed the patterns of recovery and radiative forcing on north- and south-facing slopes, stratified by vegetation classes including grassland, coastal sage scrub, chaparral, and evergreen oak forest. We found that topography strongly influenced post-fire recovery and radiative forcing. Field observations are often limited by the difficulty of collecting ground validation data. Current instrumentation networks do not provide adequate spatial resolution for landscape-level analysis. The deployment of consumer-market technology could reduce the cost of near-surface measurements, allowing the installation of finer-scale instrument networks. We tested the performance of the Microsoft Kinect sensor for measuring vegetation structure. We used Kinect to acquire 3D vegetation point clouds in the field, and used these data to compute plant height, crown diameter, and volume. We found good agreement between Kinect-derived and manual measurements.

The Vincent Gap region of the eastern San Gabriel Mountains in southern California is a small but important piece of an originally continuous terrane separated into the Tejon, Soledad and Orocopia regions by the San Andreas fault system. The middle-upper Miocene Punchbowl Formation has been considered the oldest Neogene strata of the Vincent Gap region. The present study documents that strata southeast of the main exposure of the Punchbowl Formation, though aerially restricted, are temporally extensive; together with the Punchbowl Formation, they comprise a sedimentary record that spans from ~25 to ~6 Ma, includes equivalents of the Vasquez, Tick Canyon and Mint Canyon formations of the Soledad region, and relates to three sequential tectonic stages in southern California. Uppermost Oligocene-lower Miocene strata are closely correlative with the Plush Ranch, Vasquez and Diligencia formations of the Tejon, Soledad and Orocopia regions, respectively; they formed during extension induced by triple-junction instability. Interbedded 25 Ma volcanics near the base of these strata are chemically and chronologically similar to those of the Plush Ranch, Vasquez and Diligencia formations. Middle Miocene strata beneath the Punchbowl Formation are equivalent to the Tick Canyon Formation of the Soledad region, and document exhumation of the Pelona Schist. Sandstone petrofacies, conglomerate composition and detrital-zircon age data provide compatible but distinct provenance information; using all three in combination results in a more complete understanding of the provenance of each of these units. The results of this study imply that transrotation of the western Transverse Ranges and accompanying basement exhumation extended farther inboard than generally thought, adjacent to if not across the future trace of the San Andreas fault. Data from the Vincent Gap also reveal that the middle-upper Miocene Punchbowl Formation was likely part of a large drainage system, with the Mint Canyon Formation of the Soledad region representing a tributary of this system that joined downstream, and the Caliente Formation of the Tejon region representing the confluence of the two.

Background: Characteristics such as quality patient care, excellence in nursing, and innovations in professional nursing practice shape a health care organization into a "magnet" organization. Magnet designation is a key aspect of nursing, which places pressure on healthcare organizations to commit to nursing excellence and patient care should they take the challenge of attaining this prestige. With growing focus on quality and safety, nursing needs to remain diligent in ensuring a healthy work environment that not only supports the profession, but also sustains exceptional patient outcomes. The purpose of this research study was to describe the relationship of the nurse practice environment and peripheral intravenous (PIV) infiltrations in a large urban stand-alone, pediatric teaching hospital on the Magnet journey. Methods: A descriptive correlational design with an on-line self-administered nurse survey was used for the study. The research setting took place in a large urban stand-alone, pediatric teaching hospital located in Southern California. The sampling plan included purposive, non-randomized sampling of eligible nurses who spent at least 50% of their time in direct patient care in any of the selected five types of inpatient units, with a minimum of six months employment on their current unit. An on-line self-administered nurse survey was sent to an estimated 400 nurses during August/May 2014. The study measures were organized into 3 dimensions: PIV infiltrations, Nurse Attributes, and Nurse Practice Environment. Descriptive and inferential statistics were conducted using SPSS version 22. Results: The research findings from this study indicated there were several statistically significant relationships with PIV infiltrations, Nurse Attributes, and the Nurse Practice Environment. Data showed that a nurse who works on the Medical Inpatient Units has a higher proportion of experiencing PIV infiltrations, as well as not experiencing PIV infiltrations. Subsequently, the PES-NWI subscale score by nursing unit presented statistically significant differences in one or more of the nursing units in 4 of the 5 PES-NWI subscales. Overall, the PES-NWI composite mean score was 2.87, which indicated that nurses were generally satisfied with their work environment in their current job. Additionally, Nursing Unit and Years as RN on Primary Unit indicated a statistically significant association with PIV infiltrations. This supports the inference that the unit on which the nurse works does matter in relation to experiencing or not experiencing PIV infiltrations. Conclusions: This study highlighted the importance of how the nurse practice environment and nursing-sensitive indicators contribute to pediatric patient-centered outcomes for hospitals on the Magnet journey. Focusing on measures that matter to consumers will enhance the success of healthcare organizations in supporting important quality initiatives for continuous improvement, and sustainability of nursing work culture and patient outcomes. The study findings can also help us better understand the associations amongst the nurse practice environment and patient outcomes, and provide a framework for nursing and their professional impact and responsibilities in addressing current and future healthcare demands.

Technologies continue to transform the many ways that we read, write, and communicate, redefining what it means to be literate in the 21st century. For example, the explosive growth in tablet computers over the last few years has seemingly everyone embracing the new digital literacies without any real knowledge of the skills, strategies, and dispositions required to comprehend digital text. Given the newness of this technology, it's hardly surprising that little empirical research has been conducted to examine the extent to which e-books can actually improve comprehension as well as the motivation to read among students. To help solve this problem, a randomized control trial was conducted in a Southern California middle school with four 6th grade classrooms––two that received a digital literacy intervention and two that did not. The 6-week intervention consisted of independent reading of an age-appropriate e-book along with instruction on how to use the technologies associated with the digital text; the non-intervention group read the same text in standard print format. All students participated in pre- and posttests that used the Qualitative Reading Inventory to measure comprehension proficiency and the Adolescent Motivation to Read Profile to measure the motivation to read. When analysis of variance techniques were used to compare the groups, results revealed that students that received the digital intervention improved significantly more (p < .00 I) in both comprehension and motivation than those that read the printed text. In addition, regression analysis revealed that neither race, gender, standardized state test scores, nor changes in motivation were significant predictors of the change in reading comprehension; instead the only significant predictor was whether or not the student received the digital intervention. Taken together, the findings from this small sample study suggest that motivation and comprehension proficiency improved after students read an e-book on a tablet. Of course, these findings need to be replicated in larger samples, but if they are then schools clearly need to rethink resource all location decisions in an effort to promote and integrate e-books into their curriculum, which may include either leasing tablets, using bookless libraries, or all owing students to bring their own devices to class.

During the last decade, community colleges have taken a close look at the way they educate and train students, and are using an assortment of student engagement indicators in an effort to assess and document learning outcomes of their students. While these indicators have proven helpful, the extent to which new buildings, equipment, and technology have been integrated into these metrics has been sorely lacking; instead, the assumption has been that more modem facilities, equipment, and technology will improve students' learning and better prepare them for the workforce. To test this assumption, this study examined the relationship between a new facility and student outcomes at one Southern California community college, specifically addressing the extent to which student perceptions regarding their professional preparation differed between students who completed their programs before and after the new building, as well as the extent to which student perceptions of the new building, equipment, and technology correlated with indicators of student engagement, persistence, preparation for the workplace, licensure exam passage rates, and faculty perceptions of these student outcomes. Using both descriptive and inferential techniques, results revealed that students who completed their programs in the new building perceived the facilities as having a positive influence on their overall learning, preparation for the workplace, and their licensure exam, and felt their program to be of better quality than did students who completed their programs in the old building. Interestingly, the facility had no significant influence on any of the student engagement factors—academic challenge, active and collaborative learning, student effort, and student-faculty interaction—although licensure passage rates of students completing their programs in the new building were higher than students that completed their programs in the old building. Not surprisingly, faculty program directors perceived the new building, equipment, and technology as having a positive impact on student learning, and their preparation for the workplace. Taken together, these results suggest that facility characteristics may provide a means in which to capture evidence of student learning, which can be useful for both accreditation and to reassure taxpayers that their fiscal investment is meeting needs of California businesses and industries.

Guided by Pender and colleagues' (2006) revised health promotion model (HPM), this descriptive correlational study was designed to explore the relationships between personal factors (comprised of sociodemographic factors, degree of acculturation, and perceived stress), perceived health self-efficacy, perceived social support, and health promotion lifestyle behaviors (HPLBs) among a group of Arab American women (AAW) living in Southern California. A second purpose was to explore the psychometric properties of the translated version of the perceived health competence scale (PHCS). A convenience sample of 267 AAW were administered a paper copy of a self-reported survey. Four of the study's five standardized measures were available in Arabic and were tested in the Arab American populations; only the PHCS was translated to Arabic. The HPM guided the synthesis of relevant literature concerning AAW's health promotion behaviors; the model facilitated understanding of their health needs, risks, and challenges. The analysis revealed a bivariate association between the health-promotion lifestyle profile II (HPLP II) total score and the participants' age, years of residency in the United States, acculturation, perceived stress, self-efficacy, and social support. Multiple linear regression was used to examine the relationship between the study variables. Acculturation, perceived stress, perceived health self-efficacy, and perceived social support explained 46% of the variance in HPLBs scores. The Cronbach's alpha for the PHCS was .819 in both versions. Based on the participants' language preference; Arabic or English, two study groups were formed. The groups' responses on HPLP II and PHCS were compared. The Pearson product moment correlation coefficient indicated a lack of association between the participants' spoken language and their responses on both scales. Independent sample t-tests showed statistically significant differences in the physical activity, interpersonal relations, and spiritual-growth HPLP II subscales. No statistically significant differences were found on the PHCS groups' responses. The findings of this study can inform future intervention studies to address specific health promotion behaviors, such as nutrition, eating behaviors, stress management, and physical activity among AAW and women from other minority groups.

Physical activity is an integral part of preventing and managing childhood and adolescent obesity. Lack of regular physical activity has negative impact on physical and psychosocial health. Arab Americans (AAs), one of the most rapidly growing minorities in United States, tend to have a high prevalence of obesity and low participation in physical activity. The purpose of this study was to describe determinants of physical activity, including self-efficacy, social support, physical environment, and selected demographics among AA children in Southern California. A descriptive correlational study using a cross sectional design was conducted. Self-administered questionnaires were completed by children (N=206) recruited from mosques, churches, and family social gathering events located in Southern California. Descriptive and inferential statistics were used to analyze the data. Multiple linear regression was performed to examine the variance of physical activity in AA children. The majority of participants were girls (53%). The sample mean age was 12.1 (SD = 1.49) years. The mean of the final Physical Activity Questionnaire for Children (PAQ-C) summary score was 2.39 (SD = 0.648). The study participants exhibited a moderate level of physical activity. In the regression model the data explained 51.6% of the variance (F [11,194] = 18.782; P < 0.000). Participants with higher self-efficacy overcome barriers (β = .071; p = .020) and higher self-efficacy positive alternatives (β = .063; p = .025) are expected to have higher level of physical activity. Participants with greater social support from parents (β = .145; p = .017) and friends (β = .321; p = .000) are expected to have higher level of physical activity. The level of physical activity decreased as participant age increased (β = -.076; p = .001). Finally, physical environment was not a predictor of physical activity. AA children, and older AA children in particular, may need close monitoring of their physical activity. Future interventions to improve physical activity should be designed that include considerations of promoting self-efficacy and social support.

Parking cost is an important and sensitive factor in understanding travel behavior and is typically utilized in the mode choice model of regional demand forecasting models. There are various socio-economics variables that can affect the value of parking cost by employment type, time periods, and trip purposes. In this study, a set of parking cost forecasting models are developed using survey data and local socio-economic data with the objective of identifying parking cost patterns and forecasting future parking costs. This study first summarizes methods applied in previous parking cost forecasting models. Two categories of models were estimated. The first category does not consider parking space supply as a factor in forecasting TAZ parking; the second category considers both parking space supply and parking demand as explanatory variables. For each category, using current off-street parking cost survey data, linear regression models are built for hourly, daily and monthly pricing for SCAG Tier 2 Transportation Analysis Zones (TAZ) using R and Matlab. Daily parking rates are set as the base rates to generate the hourly and monthly parking cost models. The consideration of parking demand is a major contribution of this study, with demand generated based on home-based-work trip attractions for commuters by income groups in all models. This study found that daily parking rates can be explained by total employment, the proportion of office to total jobs, and the proportion of multiple to total households. Hourly parking cost can be explained based on daily parking rates and travel behavior associated with education, hospital, finance, entertainment and other employment types. The monthly parking cost model is built base on both daily and hourly parking rates as independent variables. Future work includes, integration of on-street parking costs with the current models for off-street parking.

Background: By the year 2030, the older population in the United States is projected to double from 35 to 70 million. Consequently, increasing the number of informal caregivers required to care for an aging population. Research suggests that levels of caregiver strain and their ability to cope can impact the health of caregivers. Tsai's (2003) Middle-Range Theory of Caregiver Stress guided this study and was modified to present an innovative approach which used perceived caregiver strain as a specific stressor in the Control Process of the model; it provided a basis for examining caregiver strain and its effect on the caregiver's health. Purpose: The overall purpose of this descriptive study was to describe the relationships between objective caregiver burden, relevant caregiver characteristics, perceived caregiver strain, and perceived caregiver health in a diverse group of adult caregivers providing assistance with instrumental activities of daily living (IADL) to care recipients in Southern California. Methods: A descriptive, cross sectional, correlational and multivariate design was used to study a convenience sample of eighty-one caregivers. Caregivers were recruited from churches and adult day cares in the community areas of the Southern California region. Data was collected from caregivers who participated in an interview to include a demographic questionnaire, the Lawton Instrumental Activities of Daily Living Scale (IADL), the Modified Caregiver Strain Index (CSI), and the Short Form-12 v2 Health Survey. Data Analysis Plan: SPSS version 19.0 was used to generate descriptive statistics, including measures of central tendency and dispersion include, frequencies (percentages), means, medians, standard deviations, and range for all variables. Inferential statistical analysis, including t-tests and a one-way ANOVA were performed to examine significant relationships among variables. The Chi-square/Fisher's Exact Test was used to determine significant associations between the dependent and independent variables. Conclusion: This descriptive study suggests a picture of care giving as far more complex and potentially hazardous to the health of caregivers than has been previously documented. Future research can elucidate further the factors that can promote optimal health in both the caregivers and recipients.

Since the mid-twentieth century, a shift in demographics of those attending higher education institutions has resulted in increased attention to underrepresented students and their development, specifically their social identities, including race (Cross, 1991), gender (Gilligan, 1982), and sexual orientation (Cass, 1979; D'Augelli, 1994; Fassinger, 1998). However, many theories have compartmentalized aspects of one's overall identity with little understanding of how one's social identity may influence the development of other identities. In the past decade, the concept of intersectionality (Crenshaw, 1995), which explores the interplay between one's multiple identities and the larger systems of power and privilege within society, has been applied to understanding the holistic development of college students' multiple social identities (Abes, Jones, & McEwen, 2007; Jones & McEwen, 2000). The purpose of this study was to understand how traditionally-aged gay men in college come to make meaning of the intersections of their gender and sexuality. The research questions for this study included: (a) how do gay men make meaning of their masculinity and sexuality during their college years, (b) in what ways do gender, sexuality, and other dimensions of identity intersect for gay men in college, and (c) what are the critical influences during college on their meaning-making process? Seventeen gay men attending three universities in a metropolitan city in Southern California participated in this constructivist grounded theory study (Charmaz, 2006). Data collection included two in-depth interviews for each participant as well as journaling and an activity using the Model of Multiple Dimensions of Identity as a methodological tool for identity salience. A focus group was held also to discuss the theoretical model and the major themes that emerged. The findings are represented in a theoretical model, depicted as a labyrinth that represents a nested system between the Individual and Societal Contexts. The Individual Context includes five main themes: (1) Sense of Sameness Disappears; (2) Compartmentalizing Identit(ies); (3) Seeking Community; (4) Questioning Allegiances; and (5) Living in the Nexus. The Societal Context includes two main themes: (1) Socialization of Hegemonic Masculinity and the Inherent Tensions and (2) Heteronormativity and Homophobia as Internal and External Influences.

This study explores tobacco-use related environment, intrapersonal factors, and smoking initiation in Thai-American adolescents aged 10 to 16 living in Southern California. A purposive sample of 217 youth was recruited from seven Thai-community centers located in four counties of Southern California: The sample was fairly evenly distributed by gender with female (54.5%) and almost three quarters (70.9%) were born in the United States (70.9%). Age ranged from 10 to 16 years, with the mean age 12.71 years old (SD =1.835); 27% reported age of 11. Data were collected using the 97 item Teen Tobacco-Use Questionnaire. Findings indicated 12 participants (6.3%) reported ever trying a cigarette and 2 (1.1%) reported smoking daily. Approximately half (n = 91, 48.9%) of the sample had been exposed to family smoking, 34 (18%) reported having at least one closet friend who smoked and 15 (7.93%) having friends who used chewing tobacco, snuff, of dip. 167 (88.4%) were exposed to smoking advertisings at least some of the time from at least one source. Interpersonal factors included self-esteem subscales of self, family, school, and sensation seeking. Slightly more than half of the sample reported a high level of family self-esteem, but a low level of other self-esteem subscales and sensation seeking. Gender, age group, and school grade level were statistically significant different in exposure to tobacco-use related environment and intrapersonal environment. Exposure to tobacco-use related environment was positively correlated with belief and attitude toward smoking, intention to smoke, and smoking initiation. Family, school, and friend self-esteem subscales were inversely correlated with intention to smoke and smoking initiation, in contrast sensation seeking was positively correlated with intention to smoke and smoking initiation. Intention to smoke was statistically significantly predictive on smoking initiation. Belief and attitude toward smoking increased the odds while school self-esteem subscale decreased the odds of intention to smoke. Findings suggested tobacco-use promotional environment influence intention of smoking and smoking initiation. On the other hand, intrapersonal environment play a role as a protective factor among the adolescents in this study.

Estuaries are dynamic ecosystems at the interface of terrestrial and oceanic nutrient cycles. Nitrogen (N) fixation and denitrification are key N-cycle components that add or remove N, respectively. In mediterranean-type estuaries, wet and dry seasons affect freshwater inflows and nutrient inputs, and greater coastal development and agriculture increases anthropogenic nutrient inputs, often leading to eutrophication. My research expands understanding of N-cycling in modified mediterranean-type estuaries subject to increasing nutrient influences. Using field surveys and manipulations, I investigated spatial and temporal patterns of N-fixation and relationships with abiotic characteristics and impacts of nutrient inputs on N-fixation and denitrification in unvegetated sediments of intertidal mudflats in southern California estuaries.A 2-year survey determined N-fixation was influenced by seasonal precipitation, yet played a minor role in supplying N. During dry conditions porewater ammonium (NH4+) and nitrate (NO3-) were negatively related to N-fixation. In wet conditions, porewater salinity and N-fixation showed a negative relationship, despite simultaneously high NO3-. Only a small proportion of N-fixation variability was explained by these factors, possibly because salinity and NO3- typically co-vary and have conflicting relationships with N-fixation.In a microcosm experiment, sediments were subjected to elevated NO3- and phosphate (PO43-) concentrations, alone and together. NO3- concentrations up to 2730μM significantly affected both processes; N-fixation decreased up to 40%, while denitrification increased up to 180-fold. However, denitrification was too low to compensate for high N inputs. In a small, highly modified estuary, I determined N-fixation and denitrification rates under simulated low and high tide and NO3- enriched conditions. There were no differences in N-fixation or denitrification between ambient emerged and submerged conditions, suggesting rates do not vary across tidal cycles. Both processes responded significantly to N-enrichment; N-fixation decreased up to 9-fold and denitrification increased more than 100-fold. Overall, N-fixation rates were comparable to other eutrophic mediterranean-type systems, though lower than in more oligotrophic systems. Denitrification was lower than in other eutrophic estuaries despite dramatic increases in activity under high NO3-. These results provide insight into how N is supplied internally in mediterranean-type estuaries with anthropogenic nutrient impacts and suggest additional nutrient management strategies are necessary to reduce anthropogenic eutrophication.

Vertical accretion, the aggregation of material on a wetland surface, depends on organic matter accumulation and mineral sedimentation. We measured suspended sediment concentrations by total suspended solids (TSS), sediment deposition and vertical accretion rates in four marsh zones in the central basin of Mugu Lagoon, a salt marsh dominated by Salicornia pacifica. Mean TSS was 21±1 mg l-1 (Mean±SE) between February and May 2012, which is within the middle of the range of other salt marshes. Mean sediment deposition ranged from 0.00 g m-2 day-1 to 1.29 g m-2 day-1, which is in the low end of the range of other salt marshes. No net vertical accretion was observed between August 2011 and May 2012. Our results indicate that for high and high-mid marsh zones, sedimentation was highest adjacent to the creek. Interestingly, organic matter concentration in TSS varied with tide height, but mineral content did not. While more data are needed to confirm whether these trends occur over longer time periods, our study is one of the first to characterize spatial and temporal variation in sediment dynamics for a salt marsh dominated by Salicornia species.

Estuaries are dynamic ecosystems at the interface of terrestrial and oceanic nutrient cycles. Nitrogen (N) fixation and denitrification are key N-cycle components that add or remove N, respectively. In mediterranean-type estuaries, wet and dry seasons affect freshwater inflows and nutrient inputs, and greater coastal development and agriculture increases anthropogenic nutrient inputs, often leading to eutrophication. My research expands understanding of N-cycling in modified mediterranean-type estuaries subject to increasing nutrient influences. Using field surveys and manipulations, I investigated spatial and temporal patterns of N-fixation and relationships with abiotic characteristics and impacts of nutrient inputs on N-fixation and denitrification in unvegetated sediments of intertidal mudflats in southern California estuaries.A 2-year survey determined N-fixation was influenced by seasonal precipitation, yet played a minor role in supplying N. During dry conditions porewater ammonium (NH4+) and nitrate (NO3-) were negatively related to N-fixation. In wet conditions, porewater salinity and N-fixation showed a negative relationship, despite simultaneously high NO3-. Only a small proportion of N-fixation variability was explained by these factors, possibly because salinity and NO3- typically co-vary and have conflicting relationships with N-fixation.In a microcosm experiment, sediments were subjected to elevated NO3- and phosphate (PO43-) concentrations, alone and together. NO3- concentrations up to 2730μM significantly affected both processes; N-fixation decreased up to 40%, while denitrification increased up to 180-fold. However, denitrification was too low to compensate for high N inputs. In a small, highly modified estuary, I determined N-fixation and denitrification rates under simulated low and high tide and NO3- enriched conditions. There were no differences in N-fixation or denitrification between ambient emerged and submerged conditions, suggesting rates do not vary across tidal cycles. Both processes responded significantly to N-enrichment; N-fixation decreased up to 9-fold and denitrification increased more than 100-fold. Overall, N-fixation rates were comparable to other eutrophic mediterranean-type systems, though lower than in more oligotrophic systems. Denitrification was lower than in other eutrophic estuaries despite dramatic increases in activity under high NO3-. These results provide insight into how N is supplied internally in mediterranean-type estuaries with anthropogenic nutrient impacts and suggest additional nutrient management strategies are necessary to reduce anthropogenic eutrophication.

Limited health literacy is associated with failure to engage in health promotion behaviors. Few studies examine this relationship among Samoans. This study used a cross-sectional correlational design to determine health literacy levels and their relationship to health promoting behaviors in a southern California Samoan population. Health literacy (Short form Test of Functional Health Literacy in Adults) and health promotion behaviors (Health Promotion Lifestyle Profile II) were measured in a convenience sample of 87 Samoans in southern California. Data analysis employed chi-square, t-test, and one- way ANOVA. Significant associations were found for health literacy and demographic characteristics of employment and marital status. Significant relationships were found for the demographic characteristics of age on spiritual growth, marital status on physical activity, and education on overall health promotion, nutrition, spiritual growth, and interpersonal relations subscale scores. There was a significant relationship between health literacy and the health promotion subscales for physical activity and interpersonal relations. Most participants were under age 65 and exhibited adequate health literacy. Further research is needed to examine the relationship of health literacy to health promotion in the older Samoan population.

10Be terrestrial cosmogenic nuclide dating of alluvial surfaces in the Coachella Valley, southern California, shows two alluvial fan surfaces with ages of 124.2±6 ka (KOFo) and 80.1±3.5 ka (KOFi), with two additional probable depositional episodes at 60 ka (KOFy2) and 32 ka (KOFy1). When combined with additional fan dates from the Mojave and Sonoran Desert climatic regimes, statistically relevant episodes of fan production in southern California and Baja California were identified by mean standard weighted deviance analysis. Three major episodes have been identified at 73.27±2.02 ka (episode 1), 42.4±1.1 ka (episode 2) and 36.5±0.8 and a possible episode (1b) at 60 ka. These correlate well with the first 2 ka of glacial advance with the Sierra Nevada as established by dating of moraines and rock flour analysis of lake cores from Owens Lake. These data suggest that regional climate rather than global climate or local tectonics influences the production, transport, and deposition of sediment onto fan surfaces in the Sonoran and Colorado Deserts. Regional data on the ages of fan surfaces highlights a temporal link between the initiation of glacial advance and fan production. Global climate changes initiate Sierra Nevada glaciations which in turn produce a response in sedimentary processes over regional-scale areas. This suggests changes in regional climate initiate fan production when sediment is mobilized due to increased rainfall, before vegetation anchors sediment. Furthermore, the model focused upon transitions into more humid climate appropriate for the Sonoran and Colorado Deserts may be applicable to areas of similar arid climate where precipitation levels clearly control the abundance of vegetation but not globally, and so a unifying global model for fan formation may not be possible. The relationship between humidity and the presence or absence of vegetation is the key control in the Sonoran and Colorado Deserts. It is possible that during some humid periods the amount of precipitation could override the anchoring ability of vegetation bringing additional material into valleys from mountain slopes.

Research indicates that the term mentor in the context of higher education currently has multiple definitions and is used to describe a variety of programs, efforts, and formal as well as informal activities. In recent years, interdisciplinary perspectives on traditional undergraduate students have been converging around the idea that the functions and characteristics of mentoring students could be shared across the institution, creating what Daloz Parks (2000) has called a mentoring environment. This sharing of responsibility has the possibility to address what Baxter Magolda (2009) has recently identified as missing in higher education, a "holistic, theoretical perspective to promote the learning and developing of the whole student" (p. 621). A review of the literature from psychology, sociology, and student affairs documents this attempt to consider a more integrated and collaborative approach to college as a mentoring environment. The purpose of this research was to understand better how these students perceived, received, understood, and experienced one aspect of their college experience: mentoring. This qualitative study used thematic analysis to consider the input of 12 undergraduate students who have recently or will soon graduate from a private, four-year, faith-based liberal arts university in Southern California. The study was guided by the following research questions: How do graduating seniors attending a private, traditional, faith-based, four-year liberal-arts university describe mentoring? How do the students describe the formal and/or informal mentoring they have received during their college years? What suggestions do the students have for improving the university's formal and informal mentoring efforts? Based on extensive data analysis, findings revealed that students spoke to the transformative nature of relational and participatory experiences with faculty, staff and administrators as well as the value of opportunities to interact with several important adult mentors. Irrespective of efforts categorized as formal or informal mentoring, participants spoke more to the value of campus leaders showing an interest in their personal and professional development. Recommendations are offered for faculty, staff and administrators regarding a more holistic and collaborative approach to college as a mentoring environment. Beyond this study, the recommendations discussed should be considered based on individual, institutional suitability.