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This paper presents a comprehensive framework for life‐cycle carbon emission assessment of steel frame structures in seismic zones, with a particular focus on emerging self‐centering steel structures with reduced residual deformation and enhanced seismic resilience. The proposed framework is illustrated through a life‐cycle embodied carbon (EC) emission study on an office building located at Los Angeles, USA. Different structural bracing systems are considered for comparison, namely, conventional concentrically braced frame (CBF), bucking‐restrained braced frame (BRBF), and self‐centering braced frames (SCBFs). The life cycle assessment (LCA) of EC emissions mainly involves four phases: (1) components manufacturing phase, (2) construction phase, (3) operation and maintenance phase, and (4) EC emissions related to seismic hazard. For the last stage, the engineering demand parameter (EDP) is obtained through incremental dynamic analysis (IDA), and combined with the fragility function and the seismic risk curve to obtain the expected EC emissions related to seismic hazard over the life cycle. Among other findings, the results show that: (1) In the manufacturing process, the EC emissions of the emerging SCBFs are slightly increased (by up to 1.4%) compared with the two other conventional steel frames. (2) During the construction, operation, and maintenance phases, there is no difference in the EC emissions for the different structural systems. (3) The EC emissions related to potential seismic risk are reduced by up to 65.3% when the proposed self‐centering structural system (P‐SCBF) is used. (4) Compared with the CBF, the total EC emission over a 100‐year lifespan can be reduced by up to 14.6% when the P‐SCBF is used. Due to the limited deformation capacity of braces, the EC emissions of CBF and BRBF are more sensitive to increases in the intensity measure (IM). Since a building becomes difficult to repair when the maximum residual inter‐story drift exceeds 0.5%, BRBF and CBF are more susceptible to demolition due to unacceptable residual deformation, leading to higher EC emissions. The EC reduction efficiency of the emerging steel frames become more remarkable with increasing life span. [ABSTRACT FROM AUTHOR]

From the onset of the COVID‐19 pandemic, policymakers and news reports warned that restrictions on individual mobility and commercial activity could lead to a surge in domestic violence (DV). Some initial studies found evidence of greater DV incidence during the pandemic, but findings were inconsistent across locations and DV measures. This paper focuses on a single major city, Los Angeles (LA), to study the impact of the initial pandemic shutdown. We use three DV measures from police data (911 calls, crime incidents and arrests) as well as two measures from non‐police administrative sources (the county DV hotline and hospital records). We find an increase in DV calls to the police and calls to the hotline. However, we find that DV crimes recorded by police and hospital visits by female assault (and DV) victims decreased significantly, suggesting that the increase in calls came from higher reporting rates. The decrease in DV crimes is not attributable to reductions in policing intensity, as the arrest rate for DV crimes was higher during the shutdown. We conclude that the initial LA shutdown increased the rates at which people contacted authorities about DV, but decreased the overall incidence of physical DV crimes in the population. [ABSTRACT FROM AUTHOR]

This paper discusses the nonlinear dynamic seismic response of a 14‐story reinforced concrete core wall building designed with the prescriptive requirements of the 2019 California Building Code for a near‐fault site in Los Angeles, California, simulated with a detailed nonlinear analysis of the complete structure and subjected to an ensemble of three‐component ground motion input. The study follows up on a recently published work by the authors, which examined the response of the specific building to static lateral loads. The nonlinear model of the building was developed in the software FE‐Multiphys using a shell‐element implementation of the beam–truss model (BTM). The BTM has been extensively validated through prior studies for planar, flanged, and coupled walls under static and dynamic loading. The building model was subjected to an ensemble of ground motions scaled at the design and risk‐targeted maximum considered earthquake levels. The vertical ground motion component and the out‐of‐plane shear degradation of wall piers were included in the simulations. The analyses elucidate the profound effect of nonlinear flexure–shear interaction and of the multidirectional behavior of the flanged coupled core wall on the evolution and localization of damage and on residual deformations. The coupling behavior between the core wall, the slabs, and the columns is also analyzed, and the importance of modeling the nonlinear behavior of all slabs for the residual damage evaluation is demonstrated. The aim of this study is to improve the understanding of issues arising from prescriptive design requirements as well as of issues associated with limitations of standard nonlinear seismic analysis. [ABSTRACT FROM AUTHOR]

The national demand for social justice, racial equality, and criminal justice reform rightfully and painfully continues to sweep the consciousness of this nation. Community colleges were founded on educational excellence, opportunity, and access and should reflect principles of equity, justice, and community. This mission calls upon us, the most egalitarian institutions, to lead by example by making structural and permanent changes to root out the ill effects of racism and bias from our classrooms, curriculum, and workplace. In this paper, we examined equity‐minded leadership, culture, and climate at the Los Angeles Community College District, the nation's largest, and their efforts to transform their institutions, guided by their Framework for Racial Equity and Social Justice. The Framework speaks to the values of the District and directs specific action steps and commitments that will allow the colleges and District to actively build anti‐racist organizational capacity and resilience and move forward towards a more socially and racially‐just academic community. [ABSTRACT FROM AUTHOR]

As the amplification of seismic force demands due to higher‐mode effects on tall buildings is increasingly recognized as a design challenge, a number of high‐performance systems have been proposed to limit such effects through combined base shear‐limiting and moment‐limiting dual mechanisms. To better understand the influence of these dual base systems on the overall seismic behavior of tall buildings, this paper presents a study on the seismic response of Multi‐Degree‐of‐Freedom (MDOF) systems incorporating combined base shear‐limiting and moment‐limiting mechanisms. For an MDOF system with a given initial period and base strength level, the base shear‐limiting mechanism is defined by a shear strength factor, an inelastic stiffness parameter, and an energy‐dissipation parameter, while the base moment‐limiting mechanism is defined by a moment strength factor. To determine the influence of these parameters on the overall seismic responses of MDOF structures, a comprehensive parametric study was conducted, and the results were presented and discussed in terms of base displacement and rotation demands, seismic force demand amplification at the base and along the height, peak floor acceleration, peak roof drift, and absorbed energy. The numerical modeling methodology used in the parametric study was validated against 200 small‐scale shaking table tests of a scaled MDOF specimen with a base shear and moment dual‐mechanism system and was used to model MDOF structures that are representative of tall buildings with initial periods ranging from 1.0 to 10 s and having various base‐mechanism properties. The parametric study was then conducted using an ensemble of 20 Ground Motions (GM) scaled to three code‐specified seismic hazard levels for Los Angeles, California. The results of this study can be used to facilitate the design of base shear and moment dual‐mechanism systems for mitigating higher‐mode effects and enhancing the seismic resilience of tall buildings. [ABSTRACT FROM AUTHOR]

Traffic state estimation (TSE), which reconstructs the traffic variables (e.g., speed, flow) on road segments using partially observed data, plays an essential role in intelligent transportation systems. Generally, traffic estimation problems can be divided into two categories: model-driven approaches and data-driven approaches. The model-driven method is commonly used to solve TSE efficiently and calibrate the parameters of these models. The data-driven method requires a large amount of historical observed traffic data in order to improve performance accurately. In order to combine the advantages of model-driven and data-driven methods, this paper proposed a hybrid framework incorporating the traffic flow model into deep learning (TFMDL) modeling that contains both model-driven and data-driven components. This paper focuses on highway TSE with observed data from loop detectors. We build a hybrid cost function to adjust the weights of model-driven and data-driven proportions. We then evaluate the proposed framework using the open-access performance measurement system (PMS) dataset on a corridor of US I-405 in Los Angeles, California. The experimental results show the advantages of the proposed TFMDL approach in performing better than several benchmark models in terms of estimation accuracy and data efficiency. [ABSTRACT FROM AUTHOR]

Nowcasting is a term originating from economics, finance, and meteorology. It refers to the process of determining the uncertain state of the economy, markets or the weather at the current time by indirect means. In this paper, we describe a simple two‐parameter data analysis that reveals hidden order in otherwise seemingly chaotic earthquake seismicity. One of these parameters relates to a mechanism of seismic quiescence arising from the physics of strain‐hardening of the crust prior to major events. We observe an earthquake cycle associated with major earthquakes in California, similar to what has long been postulated. An estimate of the earthquake hazard revealed by this state variable time series can be optimized by the use of machine learning in the form of the Receiver Operating Characteristic skill score. The ROC skill is used here as a loss function in a supervised learning mode. Our analysis is conducted in the region of 5° × 5° in latitude‐longitude centered on Los Angeles, a region which we used in previous papers to build similar time series using more involved methods (Rundle & Donnellan, 2020, https://doi.org/10.1029/2020EA001097; Rundle, Donnellan et al., 2021, https://doi.org/10.1029/2021EA001757; Rundle, Stein et al., 2021, https://doi.org/10.1088/1361-6633/abf893). Here we show that not only does the state variable time series have forecast skill, the associated spatial probability densities have skill as well. In addition, use of the standard ROC and Precision (PPV) metrics allow probabilities of current earthquake hazard to be defined in a simple, straightforward, and rigorous way. Plain Language Summary: Earthquake nowcasting refers to the determination of hazard for major earthquakes at the present time, the recent past, and the near future. Nowcasting is an idea borrowed from economics, markets, and meteorology, where it has been frequently used. In this paper, we show that there is order hidden within chaotic earthquake seismicity using a very simple transformation of the data. Small earthquakes appear to transition from unstable stick‐slip events that produce seismic waves, to stable sliding where no seismic waves are produced. Our hypothesis is that this transition is due to a material phenomenon called strain‐hardening, that is frequently observed in laboratory rock mechanics experiments. The result is a state variable time series, computed over the last 51 years in California, that strongly resembles the long‐anticipated cycle of stress accumulation and release. Using supervised machine learning techniques, we can optimize the two‐parameter model. From that optimized model, we can rigorously calculate the probability of current hazard from major earthquakes. Extending these methods, we can also compute spatial hazard as well. The result is a new method for assessing earthquake hazard that may be useful for a variety of applications. Key Points: "Chaotic" seismicity contains hidden structure in the form of state variable time seriesStandard data science methods can be used to convert the time series to probabilitiesBoth temporal and spatial probabilities can be computed [ABSTRACT FROM AUTHOR]

Catastrophic landslides are often preceded by slow, progressive, accelerating deformation that differs from the persistent motion of slow‐moving landslides. Here, we investigate the motion of a landslide that damaged 12 homes in Rolling Hills Estates (RHE), Los Angeles, California on 8 July 2023, using satellite‐based synthetic aperture radar interferometry (InSAR) and pixel tracking of satellite‐based optical images. To better understand the precursory motion of the RHE landslide, we compared its behavior with local precipitation and with several slow‐moving landslides nearby. Unlike the slow‐moving landslides, we found that RHE was a first‐time progressive failure that failed after one of the wettest years on record. We then applied a progressive failure model to interpret the failure mechanisms and further predict the failure time from the pre‐failure movement of RHE. Our work highlights the importance of monitoring incipient slow motion of landslides, particularly where no discernible historical displacement has been observed. Plain Language Summary: Landslides exhibit a wide range of behaviors around the world. Some landslides travel slowly downslope (velocities <1 m/yr) over a period of years or even decades. In contrast, other landslides fail catastrophically and travel downslope at high rates (>1 m/s), claiming lives and causing major damages. In some cases, these catastrophic landslides also display a precursory period of slow movement which presents an opportunity to detect them before they rapidly collapse. Here we investigated the movement of the Rolling Hills Estates (RHE) landslide, Los Angeles, California, before it moved many meters and damaged more than 12 houses on 8 July 2023. This landslide occurred after one of the wettest years on record in California. We found that the RHE landslide started sliding in 2023 in response to relatively high precipitation without obvious signs of movement in the three years preceding this event. This behavior differed starkly from the persistent motion of nearby slow‐moving landslides that experienced nearly identical rainfall conditions. Our findings show that the RHE can be defined as a progressive failure and its failure time can be estimated approximately through analyzing its movement before the occurrence of the failure. Key Points: We used satellite remote sensing to characterize the precursory motion of a catastrophic landslideProgressive failures and slow‐moving landslides can be distinguished by analyzing their time‐dependent motionSpecial attention should be given to landslides where no apparent historical movement has occurred [ABSTRACT FROM AUTHOR]

To address the shortage of the aggregate used in a hot mix asphalt (HMA) pavement in Guangxi, properties such as the aggregate crushing, polished stone, and Los Angeles abrasion values of a type of hard sandstone aggregate used in HMA were tested after various conditioning treatments. The hard sandstone aggregate met the technical requirements for aggregate in HMA. In addition, the influence of the Marshall compaction on the hard sandstone aggregate-combined grading was tested. The combined grading curve changed a little, and the aggregate satisfied the corresponding technical requirements. Therefore, according to the abovementioned results, the hard sandstone aggregate can be used as a coarse aggregate in HMA. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates a Fletcher‐Reeves conjugate gradient optimized multi‐reservoir echo state network (FRCG‐MESN) to identify battery state of charge (SOC). First, an echo state network with multiple reservoirs is established to estimate battery SOC by using its discharge terminal voltage and current as the inputs, and the FR conjugate gradient algorithm is explored to tune the output weights of the MESN to avoid calculating the inverse matrix. Second, an appropriate amount of Gaussian noise with zero mean is added to the training set to prevent overfitting. Finally, a battery test platform is adopted to sample the discharging data under two working conditions: the Los Angeles 92 and the urban dynamometer driving schedule. The simulation results show that the presented FRCG‐MESN method can accurately identify the battery SOC with different initial SOCs. Applying an appropriate amount of noise to the training set can prevent overfitting efficiently. [ABSTRACT FROM AUTHOR]

This paper presents a study exploring how migrants' belonging shapes their remittances among Bangladeshi migrants in Los Angeles. Based on migrants' perception, the paper recognizes the centrality of the family and origin community in migrants' remittances both in the NELM and in the transnational perspectives. It empirically investigates migrants' belonging and recognizes their membership in their parents' family, their own nuclear family, joint family including siblings with their respective families, extended family including multiple generations and a community of origin. It finds migrants' belonging simultaneously to the destination and origin countries, and also confirms the presence of 'friction' in such belonging, indicative of both cooperation and conflict in migrants' remittances allowing for explaining changes in their remittances such as remittances decay and resurgence. This study offers guideline for further empirical research on migrants' transnationalism and remittances with policy implications regarding the developmental consequences of remittances. [ABSTRACT FROM AUTHOR]

Studying the time interval duration between the first accident and the second accident caused by it can provide decision makers with valuable information on how to effectively deal with high-risk second accidents. This paper is aimed to explore the potential influencing factors of the interval duration between the two accidents and predict it. First, the spatiotemporal definition method is applied to identify the cascaded first accident and the second accident. Then, on the basis of using Kaiser-Meyer-Olkin (KMO) measure and Bartlett's sphere test statistics to ensure the applicability of the data to the factor analysis method, the explanatory variables that can significantly affect the interval duration are obtained through the factor analysis method. Finally, the random forest model (RF), which combines the advantages of machine learning methods, is employed to predict the duration of the interval. Traffic accident data set collected in Los Angeles city from February 2016 to June 2020 is used to validate prediction performance in this study. Bayesian method is applied to optimize the hyperparameters in the RF, while three evaluation indicators, including the Root Mean Squared Error (RMSE), Mean Squared Error (MSE), and Mean Absolute Percentage Error (MAPE), are used to estimate the prediction effect. The test results and comparative experiments confirm that RF is able to predict the interval well and has better prediction performance. This is of great significance for the prediction of the duration of the interval between one accident and the second accident. [ABSTRACT FROM AUTHOR]

Leisure activities, including place‐based food experiences, have become central to defining urban identities and branding places. Mobile and affluent urbanites' search for authentic and cosmopolitan experiences is increasingly guided by corporate digital media such as apps and websites that direct them to previously ignored working‐class, ethnic and immigrant neighborhoods, which are being discursively and materially reconfigured to meet their needs, in turn causing the displacement of long‐time residents. We examine the relationship between food and gentrification through the lens of digital media, suggesting that they play an important role in shaping urban experiences and cities. Specifically, we investigate narratives produced by popular digital food media, not least websites and apps providing restaurant ratings and reviews, and their relationship to ongoing patterns of gentrification in Buenos Aires, Los Angeles and Paris. Using mixed methods that combine census data with 'hybrid fieldwork' in online and offline foodscapes, we identify some spatial patterns and key characteristics of food‐driven gentrification, highlighting the aestheticization of everyday life and its significance in encouraging and legitimizing planetary gentrification. [ABSTRACT FROM AUTHOR]

While random permutations of point processes are useful for generating counterfactuals in bivariate interaction tests, such permutations require that the underlying intensity be separable. In many real‐world datasets where clustering or inhibition is present, such an assumption does not hold. Here, we introduce a simple combinatorial optimization algorithm that generates second‐order preserving (SOP) point process permutations, for example, permutations of the times of events such that the L function of the permuted process matches the L function of the data. We apply the algorithm to synthetic data generated by a self‐exciting Hawkes process and a self‐avoiding point process, along with data from Los Angeles on earthquakes and arsons and data from Indianapolis on law enforcement drug seizures and overdoses. In all cases, we are able to generate a diverse sample of permuted point processes where the distribution of the L functions closely matches that of the data. We then show how SOP point process permutations can be used in two applications: (1) bivariate Knox tests and (2) data augmentation to improve deep learning‐based space‐time forecasts. [ABSTRACT FROM AUTHOR]

Because foundation species create structure in a community, understanding their ecological and evolutionary responses to global change is critical for predicting the ecological and economic management of species and communities that rely on them. Giant kelp (Macrocystis pyrifera) is a globally distributed foundation species with seasonal fluctuations in abundance in response to local nutrient levels, storm intensity, and ocean temperatures. Here we examine genetic variation in individual and population‐level responses of early life history stages (zoospore settlement, survival, and gametogenesis) to increased temperatures to determine the potential for natural selection on temperature‐tolerant individuals that would allow adaptation to a changing climate. We collected fertile M. pyrifera sporophyll blades from three sites along the California coast (Los Angeles, Santa Barbara, Monterey Bay) and induced zoospore release in the lab. Spores settled on microscope slides at three treatment temperatures (16, 20, and 22°C), matured for 21 days, and were imaged weekly to determine settlement, survival, and maturation success. On average, individuals from all sites showed lower rates of settlement and maturation in response to increasing temperature. However, the magnitude of the responses to temperature varied among populations. Survival tended to increase with temperature in Los Angeles and Santa Barbara populations but decreased with increasing temperature for the Monterey Bay population. We observed little genetic variation in temperature responses among individuals within sites, suggesting little scope for evolution within populations to increase the resilience of M. pyrifera populations to warming ocean temperatures and predicted declines in kelp abundance. Yet sufficient dispersal among populations could allow for adaptation of early life history traits among populations via evolutionary rescue of declining populations. [ABSTRACT FROM AUTHOR]

Access to safe and affordable financial services is essential to the economic well‐being of individual households and entire urban neighborhoods. However, prior research raises concerns about spatial inequities in the distribution of brick‐and‐mortar financial services offerings—either mainstream financial institutions or alternative 'fringe' financial service providers—and the resulting implications for financial inclusion and social justice. This study uses a novel method to identify fringe financial ecologies that captures the recent tandem processes of abandonment by mainstream financial institutions and the proliferation of alternative financial service providers. We explore how fringe financial ecologies potentially overlap existing inequalities of race, class and subprime mortgage lending in two US metropolitan areas, Los Angeles, California, and Miami, Florida. Our results raise concerns that communities of color, low‐income neighborhoods and otherwise vulnerable segments of the population are disproportionately at risk of both financial exclusion and predatory targeting. We find that fringe financial ecologies are associated with a high prevalence of subprime mortgage lending. The results advance an understanding of financial ecologies that raises awareness about place‐based financial exclusion as a form of systemic racism in the broader context of the national reckoning with racial justice in the US. [ABSTRACT FROM AUTHOR]

Scholarship and advocacy on mobility justice needs to attend carefully to how presumptions about mobile embodiment are reproduced. This paper critically assesses some of the presumptions about the mobile subject within cycling interventions that focus on behaviour and infrastructural change. Bringing material and Black feminist theory together with ethnographic fieldwork on urban cycling in Los Angeles in 2014–2015, I suggest mobile subjectivity can be understood through the process of enfleshment, rather than centring on individualised cycling embodiment. Imagined through the cycling lungs, enfleshment allows for a mobile subjectivity that is inherently exposed in highly uneven ways; configured through matter and meaning; and a materialisation of relations of power distributed across space and time. Thinking with enfleshment contributes to cycling advocacy, mobility justice and geographical theory on the body by shifting how mobile subjects are understood and how difference, justice and the politics of the street are imagined and practised. [ABSTRACT FROM AUTHOR]

This paper presents the Evolvability Analysis Framework (EAF), a new perspective on evaluating complex infrastructure systems. EAF enables decision makers to explore alternative transition paths, thus providing several multi‐step options to achieve a desired end state. These multi‐step transition paths can be particularly valuable when they mitigate the impact of system degradation during the deployment of new capabilities. Additionally, EAF is formulated in a manner that empowers decision makers to apply decision variables, such as a cost cap or an equity metric, which are increasingly relevant to modern decision‐making. To demonstrate the method and its value, we apply the EAF to a case study inspired by Los Angeles' Vision 2028. We identify 26 transition paths across different performance dimensions. We model the cost and performance of each transition pathway and compare them using multiple measures, including traditional benefit‐cost metrics and differential impacts on different stakeholder groups. Our results show that multi‐step paths outperform single‐step transitions to an end state ("big bang" approaches) in most scenarios. Multi‐step paths also provide valuable alternatives when particular stakeholders value non‐cost metrics. [ABSTRACT FROM AUTHOR]

Summary: High‐rise buildings are an efficient solution to meet the housing challenges of global urbanization that is happening at an incredible pace. Code‐based seismic design philosophies are aimed at achieving collapse‐prevention under major earthquakes, implying extensive structural damage associated with important losses. A number of high‐performance systems have been investigated for enhancing the resilience of high‐rise buildings whose design is especially challenging due to higher‐mode effects even when a flexural mechanism is formed at the base of the structure. To this end, this paper proposes a new concept consisting of a three‐dimensional uncoupled rocking and shear mechanism system for high‐rise buildings where reinforced concrete (RC) core walls are used as the lateral‐force‐resisting system. The proposed system provides a dual‐mechanism at the base that independently limits both overturning moments (OTMs) and shear forces and thus more effectively mitigates higher‐mode effects. The characteristic mechanics of the proposed system are first studied through an idealized model. A physical embodiment is then designed, detailed, and validated through advanced models and extensive nonlinear dynamic analyses. A 42‐story RC core‐wall building that is located in Los Angeles and was studied as part of the PEER Tall Buildings Initiative is used as a reference structure in this study. Results confirmed that the proposed system eliminates damage at the base of the walls and minimizes the inelastic demands over the height of the building. In a general sense, the proposed concept provides a framework in which the intended dual mechanism can be implemented to a wider range of high‐rise structures. [ABSTRACT FROM AUTHOR]

This article argues that three prominent recent works of Los Angeles climate fiction—Maria Amparo Escandon's L.A. Weather (2021), Alexandra Kleeman's Something New Under the Sun (2021) and Paul Beatty's The Sellout (2016)—generate a sense of planetary responsibility. Despite their regional settings, these novels possess a planetary consciousness, illuminating the local‐global connectivity of climate change and the Anthropocene. As one of the biggest greenhouse gas emitting cities in the world, L.A. drives climate injustice, with its gargantuan energy consumption having an adverse impact on populations both within and far beyond its own borders. This article explains how literature, and climate fiction particularly, can highlight this inequality at micro and macro scales, and encourage collective opposition to it. I argue that the novels of Escandon, Kleeman and Beatty conjure the impression of responsibility identified by Kristian Shaw and Sara Upstone in their overview of post‐postmodern fiction, while also exhibiting the 'planetarity' discussed by Amy Elias and Christian Moraru: a term to describe the global worldview of contemporary culture. In applying these concepts to the novels examined here, I ultimately contend that Los Angeles climate fiction demystifies the spatial and political dimensions of the Anthropocene, generating planetary responsibility and addressing local and global injustice. [ABSTRACT FROM AUTHOR]

A growing constellation of satellites is providing near‐global coverage of column‐averaged CO2 observations. Launched in 2019, NASA's OCO‐3 instrument is set to provide XCO2 observations at a high spatial and temporal resolution for regional domains (100 × 100 km). The atmospheric column version of the Stochastic Time‐Inverted Lagrangian Transport (X‐STILT) model is an established method of determining the influence of upwind sources on column measurements of the atmosphere, providing a means of analysis for current OCO‐3 observations and future space‐based column‐observing missions. However, OCO‐3 is expected to provide hundreds of soundings per targeted observation, straining this already computationally intensive technique. This work proposes a novel scheme to be used with the X‐STILT model to generate upwind influence footprints with less computational expense. The method uses X‐STILT generated influence footprints from a key subset of OCO‐3 soundings. A nonlinear weighted averaging is applied to these footprints to construct additional footprints for the remaining soundings. The effects of subset selection, meteorological data, and topography are investigated for two test sites: Los Angeles, California, and Salt Lake City, Utah. The computational time required to model the source sensitivities for OCO‐3 interpretation was reduced by 62% and 78% with errors smaller than other previously acknowledged uncertainties in the modeling system (OCO‐3 retrieval error, atmospheric transport error, prior emissions error, etc.). Limitations and future applications for future CO2 missions are also discussed. Plain Language Summary: Several satellites are providing near‐global observations of Earth's atmospheric carbon dioxide (CO2). One example is NASA's new OCO‐3 instrument which is set to provide spatially dense CO2 measurements over targeted areas. Measurements may contain signals of emissions from cities and power plants. One method of finding the source(s) of observed CO2 is using a Lagrangian particle dispersion model such as X‐STILT. This model takes OCO‐3 measurements and runs atmospheric transport backwards in time to trace out the sources affecting these measurements. However, OCO‐3 and future satellite missions will yield many measurements, significantly increasing the computational cost for X‐STILT and other similar models. This paper presents an algorithm that will reduce the computational effort for X‐STILT by tracing the sources of only a subset of OCO‐3 measurements and then infers (interpolates) the rest. The following two questions are addressed: (1) How many OCO‐3 measurements does X‐STILT need for the interpolations to be accurate? (2) How do meteorology and topography affect the accuracy of the interpolations? Applying the algorithm on simulated OCO‐3 data at two test cities—Los Angeles and Salt Lake City—the time required to elucidate the CO2 sources was reduced by 62% and 78%, respectively. Key Points: Determining sources of spatially dense XCO2 observations with LPDM techniques can become time intensive and strain computational resourcesPresented in this work is an interpolation scheme that eases the computational burden of spatially dense XCO2 source determination studiesEvaluating the efficiency of this interpolation scheme revealed reductions of >50% in computational time at two testing locations [ABSTRACT FROM AUTHOR]

Interest in retail seafood sales increased dramatically with the onset of the COVID‐19 pandemic. The diversity of species, types of products, product forms, and packaging of the seafood sold at retail, combined with diverse consumer preferences across the United States, requires detailed data and analysis to provide guidance and understanding of emerging trends. Weekly, store‐based, Nielsen Scantrack data for the period of September 2016 through August 2021 were used to compare trends in US retail (supermarket) seafood sales across the 5‐year study period, in continental regions, cities, and species categories sold. Results showed continuous increases in retail seafood sales over the study period at an average annual growth rate of 8.1%, much of which was fueled by the 21% increase in total sales (19.5% increase in quantity sold) the first year after the onset of the pandemic. The South Atlantic region was found to have the greatest total sales and sales per capita among regions. New York City had the greatest total seafood sales, followed by Los Angeles and Philadelphia. The top five most important species categories in terms of sales were, in declining order, shrimp, salmon, tuna, crab, and tilapia, although regional variability became apparent from the fourth‐ranked species. The most important package sizes were 454‐ and 907‐g packs. Frozen and refrigerated categories dominated sales (70% in 2021), with little growth in entrées and a decline in market share of shelf‐stable seafood products in 2021. Retail supermarket seafood sales increased dramatically following the onset of the pandemic, with especially notable percentage increases in lobster (77%) and crab sales (70%) and the lowest percentage increases in tuna (1%) and tilapia (13%). Given that US per capita seafood consumption did not show a corresponding increase over the study period, study results likely indicate a shift to greater relative consumption at home and not an overall increase in US seafood sales. [ABSTRACT FROM AUTHOR]

In 2019, Los Angeles, California's City Hall was reported to be infested with rats. LA's pest control contractor later drew a link between this rat problem and nearby encampments of unhoused residents. I use these connected cases of homelessness and rat control in Los Angeles to investigate the spatial and symbolic logics that guide urban social processes. Using computational and qualitative text analysis, interviews, and participant observation, I argue that rats and homelessness are issues tied to the proper place of nature in cities. While urban nature is central to the aspirational goals of urbanization, where institutions craft a desirable, recognizably urban life, I argue that managing it means not just introducing "good" nature (parks, street trees, etc.) to cities, but also keeping "bad" nature at bay. Practically, this entails guarding public faith in the boundary between "indoors" and "outdoors." Homelessness and rat infestations present challenges to this goal because they represent inverse spatial transgressions of the indoors/outdoors divide. Rats bring the outdoors inside, compromising safety and security. Homeless encampments, meanwhile, represent domestic, indoor life spilling over into the outdoors. City institutions materially maintain the indoors/outdoors divide and symbolically attend to it by removing meaningful indications of these spatial transgressions. [ABSTRACT FROM AUTHOR]

COVID‐19 lockdowns caused significant improvements in air quality in US states where traffic emissions are the main pollution source. In this study, we investigate the socioeconomic impacts of the COVID‐19‐related lockdowns in states which experienced the greatest changes in air quality, especially among different demographic populations and those with contraindications to health. We administered a 47‐question survey and collected 1,000 valid responses in these cities. Our results show that 74% of respondents within our survey sample had some level of concern regarding air quality. In agreement with previous literature, perceptions of air quality were not significantly correlated with measured air quality criteria but rather seemed to be influenced by other factors. Respondents in Los Angeles were the most concerned about air quality followed by Miami, San Francisco, and New York City. However, those from Chicago and Tampa Bay expressed the least amount of concern about air quality. Age, education, and ethnicity were all factors affecting peoples' concerns about air quality. Respiratory conditions, living in proximity to industrial areas, and financial impacts from the COVID‐19 lockdowns influenced concerns about air quality. About 40% of the survey sample reported greater concern for air quality during the pandemic, while approximately 50% stated that the lockdown didn't affect their perception. Furthermore, respondents seemed concerned about air quality in general, not a specific pollutant, and are willing to adopt additional measures and more stringent policies to improve air quality in all investigated cities. Plain Language Summary: COVID‐19 lockdowns caused significant improvements in air quality in US states where traffic emissions are the main pollution source. In this study, we investigated the socioeconomic impacts of the COVID‐19‐related lockdowns in states which experienced the greatest changes in air quality, especially among different demographic populations and those with contraindications to health. We administered a 47‐question survey and collected 1,000 valid responses in these cities. Our results show that 74% of respondents within our survey sample had some level of concern regarding air quality. In agreement with previous literature, perceptions of air quality were not significantly correlated with measured air quality criteria but rather seemed to be influenced by other factors. Respondents in Los Angeles were the most concerned about air quality followed by Miami, San Francisco, and New York City. Those from Chicago and Tampa Bay expressed the least amount of concerns. Age, education, and ethnicity were all factors affecting peoples' concerns about air quality. Respiratory conditions, living in proximity to industrial areas, and financial impacts from the COVID‐19 lockdowns influenced concerns about air quality. Respondents seemed concerned about air quality in general, not a specific pollutant, and are willing to adopt additional measures to improve air quality. Key Points: Most survey respondents (74%) were concerned about air qualityAge, education, and ethnicity were factors that affected peoples' concerns about air qualityRespiratory conditions, living near industrial areas, and financial status impacted perceptions [ABSTRACT FROM AUTHOR]

The scarcity of strong ground motion records presents a challenge for making reliable performance assessments of tall buildings whose seismic design is controlled by large‐magnitude and close‐distance earthquakes. This challenge can be addressed using broadband ground‐motion simulation methods to generate records with site‐specific characteristics of large‐magnitude events. In this paper, simulated site‐specific earthquake seismograms, developed through a related project that was organized through the Southern California Earthquake Center (SCEC) Ground Motion Simulation Validation (GMSV) Technical Activity Group, are used for nonlinear response history analyses of two archetype tall buildings for sites in San Francisco, Los Angeles, and San Bernardino. The SCEC GMSV team created the seismograms using the Broadband Platform (BBP) simulations for five site‐specific earthquake scenarios. The two buildings are evaluated using nonlinear dynamic analyses under comparable record suites selected from the simulated BBP catalog and recorded motions from the NGA‐West database. The collapse risks and structural response demands (maximum story drift ratio, peak floor acceleration, and maximum story shear) under the BBP and NGA suites are compared. In general, this study finds that use of the BBP simulations resolves concerns about estimation biases in structural response analysis which are caused by ground motion scaling, unrealistic spectral shapes, and overconservative spectral variations. While there are remaining concerns that strong coherence in some kinematic fault rupture models may lead to an overestimation of velocity pulse effects in the BBP simulations, the simulations are shown to generally yield realistic pulse‐like features of near‐fault ground motion records. [ABSTRACT FROM AUTHOR]

The aeronautical community is currently researching technology that might lead to commercial hypersonic aircraft that would cruise at Mach 5–8 in the middle or upper stratosphere and would transfer passengers from London to New York or from Los Angeles to Tokyo in just a couple of hours. Depending on the engine technology to be adopted, these aircraft will potentially release substantial amounts of water vapor and nitrogen oxides around 30–40 km altitude. We show here that the operation of a large fleet of such aircraft could potentially deplete considerable amounts of ozone in the stratosphere, which would lead to a substantial increase in biologically damaging ultraviolet radiation reaching the Earth's surface. The calculations are based on a specific emission scenario, which carries large uncertainties but can easily be scaled to account for the type of aircraft engine to be eventually adopted, improved technology to be expected, and the size and operation conditions of the future aircraft fleet. Plain Language Summary: Commercial hypersonic aircraft, if developed in the future, will be flying at Mach 5 to 8 in the middle to upper stratosphere (30 to 40 km altitude) to carry passengers in a couple of hours from London to New York or from Los Angeles to Tokyo. Depending on the adopted technology and fleet size, the powerful engines of such airplanes may release substantial amounts of water and nitrogen oxides in the stratosphere, which could potentially damage the protecting ozone layer and hence increase the level of biologically damaging ultraviolet radiation reaching the Earth surface. The paper uses an advanced global atmospheric model to assess the impact of a potential fleet of hypersonic aircraft. Key Points: Hypersonic transport (HST) releasing nitrogen oxides and water vapor have the potential to reduce the stratospheric ozone abundancePer Tg injection of nitrogen oxides, the calculated ozone depletion is larger for aircraft flying at 30 km than 40 km altitudeOzone decrease near the HST flight altitude is reduced by about a third when temperature and dynamical feedbacks are taken into account [ABSTRACT FROM AUTHOR]

This paper studies unobserved heterogeneity in hedonic price models, arising from missing property and locational characteristics. Specifically, commercial real estate is very heterogeneous, and data on detailed property characteristics are often lacking. We show that adding mutually independent property random effects to a hedonic price model results in more precise out‐of‐sample price predictions, both for commercial multifamily housing in Los Angeles and owner‐occupied single‐family housing in Heemstede, the Netherlands. The standard hedonic price model does not take advantage of the fact that some properties sell more than once. We subsequently show that adding spatial random effects leads to an additional increase in prediction accuracy. The increase is highest for properties without prior sales. [ABSTRACT FROM AUTHOR]

People living near oil and gas development are exposed to multiple environmental stressors that pose health risks. Some studies suggest these risks are higher for racially and socioeconomically marginalized people, which may be partly attributable to disparities in exposures. We examined whether racially and socioeconomically marginalized people in California are disproportionately exposed to oil and gas wells and associated hazards. We longitudinally assessed exposure to wells during three time periods (2005–2009, 2010–2014, and 2015–2019) using sociodemographic data at the census block group‐level. For each block group and time period, we assessed exposure to new, active, retired, and plugged wells, and cumulative production volume. We calculated risk ratios to determine whether marginalized people disproportionately resided near wells (within 1 km). Averaged across the three time periods, we estimated that 1.1 million Californians (3.0%) lived within 1 km of active wells. Nearly 9 million Californians (22.9%) lived within 1 km of plugged wells. The proportion of Black residents near active wells was 42%–49% higher than the proportion of Black residents across California, and the proportion of Hispanic residents near active wells was 4%–13% higher than their statewide proportion. Disparities were greatest in areas with the highest oil and gas production, where the proportion of Black residents was 105%–139% higher than statewide. Socioeconomically marginalized residents also had disproportionately high exposure to wells. Though oil and gas production has declined in California, marginalized communities persistently had disproportionately high exposure to wells, potentially contributing to health disparities. Plain Language Summary: People living near oil and gas wells are exposed to pollutants that may adversely affect their health. We investigated whether racially or socioeconomically marginalized people in California had disproportionately higher exposure to wells. We also assessed whether disparities were wider in areas with more intensive oil and gas production. We examined changes in neighborhood‐level sociodemographic characteristics in three time periods: 2005–2009, 2010–2014, and 2015–2019. For each neighborhood and time period, we estimated the number of wells and the total volume of oil and gas produced within 1 km (0.62 miles). We estimated that approximately 1.1 million Californians (3.0%) lived within 1 km of active wells between 2005 and 2019. The proportion of Black residents living near active wells was 42%–49% higher than the proportion of Black residents across California, and the proportion of Latinx residents near active wells was 4%–13% higher than their statewide proportion. For Black people, the disparities were widest in Los Angeles County neighborhoods with the most intensive production. Socioeconomically marginalized people also had disproportionately high exposure. Most disparities persisted throughout the 15‐year study period. Black, Hispanic, and socioeconomically marginalized people had disproportionately high exposure to wells, potentially contributing to health disparities. Key Points: Black, Hispanic, and socioeconomically marginalized people persistently had disproportionately high exposure to oil and gas developmentThe widest observed disparities were for Black people residing in neighborhoods with the most intensive oil and gas productionDisparities in exposure to oil and gas development may contribute to previously reported health disparities [ABSTRACT FROM AUTHOR]

The exposome is an ideal in public health research that posits that individuals experience risk for adverse health outcomes from a wide variety of sources over their lifecourse. There have been increases in data collection in the various components of the exposome, but novel statistical methods are needed that capture multiple dimensions of risk at once. We introduce a Bayesian index low‐rank kriging (LRK) multiple membership model (MMM) to simultaneously estimate the health effects of one or more groups of exposures, the relative importance of exposure components, and cumulative spatial risk over time using residential histories. The model employs an MMM to consider all residential locations for subjects weighted by duration and LRK to increase computational efficiency. We demonstrate the performance of the Bayesian index LRK‐MMM through a simulation study, showing that the model accurately and consistently estimates the health effects of one or several group indices and has high power to identify a region of elevated spatial risk due to unmeasured environmental exposures. Finally, we apply our model to data from a multicenter case‐control study of non‐Hodgkin lymphoma (NHL), finding a significant positive association between one index of pesticides and risk for NHL in Iowa. Additionally, we find an area of significantly elevated spatial risk for NHL in Los Angeles. In conclusion, our Bayesian index LRK‐MMM represents a step forward toward bringing the ideals of the exposome into practice for environmental risk analyzes. [ABSTRACT FROM AUTHOR]

The Los Angeles region contains a number of heavily altered watersheds, resulting in the degradation of both water and habitat quality along numerous streams. Assessing the impacts of these anthropogenic stressors on biological communities has primarily focused on the California Stream Condition Index (CSCI), a measure of the biotic integrity of benthic macroinvertebrate assemblages. To complement the CSCI an Algal Stream Condition Index (ASCI) was developed to assess the biotic integrity of both soft‐bodied and diatomaceous algal assemblages. Using random forest modeling, we evaluated the performances of the CSCI, the ASCI for diatom assemblages (D_ASCI), and the ASCI for hybrid assemblages containing both diatoms and soft‐bodied algae (H_ASCI). We found that our models of the D_ASCI and H_ASCI could account for approximately 77% and 78% of their observation variation across the watersheds of the Los Angeles region, nearly as high as the 82% accounted for by the CSCI. This indicates the future potential of using indices of biotic integrity based on, or in part, diatom assemblages for streams in this region as additional forms of bioassessment. [ABSTRACT FROM AUTHOR]

Researchers commonly "shrink" raw quality measures based on statistical criteria. This paper studies when and how this transformation's statistical properties would confer economic benefits to a utility‐maximizing decision‐maker across common asymmetric information environments. I develop the results for an application measuring teacher quality. The presence of a systematic relationship between teacher quality and class size could cause the data transformation to do either worse or better than the untransformed data. I use data from Los Angeles to confirm the presence of such a relationship and show that the simpler raw measure would outperform the one most commonly used in teacher incentive schemes. [ABSTRACT FROM AUTHOR]

Legislation in the State of California mandates reductions in emissions of short‐lived climate pollutants of 40% from 2013 levels by 2030 for CH4. Identification of the sector(s) responsible for these emissions and their temporal and spatial variability is a key step in achieving these goals. Here, we determine the emissions of CH4 in Los Angeles from 2011–2017 using a mountaintop remote sensing mapping spectrometer. We show that the pattern of CH4 emissions contains both seasonal and nonseasonal contributions. We find that the seasonal component peaks in the winter and is correlated (R2 = 0.58) with utility natural gas consumption from the residential and commercial sectors and not from the industrial and gas‐fired power plant sectors. The nonseasonal component is (22.9 ± 1.4) Gg CH4/month. If the seasonal correlation is causal, about (1.4 ± 0.1)% of the commercial and residential natural gas consumption in Los Angeles is released into the atmosphere. Plain Language Summary: CH4 is a desirable target for greenhouse gas emission reductions because emission controls will have a rapid impact on radiative forcing. However, its emission budget is highly uncertain and poorly quantified. This paper reports new results from a novel mountaintop remote sensing spectrometer overlooking the Los Angeles basin. The study shows that the megacity's methane emissions are strongly correlated with the consumption of natural gas by residential and commercial consumers, with a leakage rate of (1.4 ± 0.1)%, while the nonseasonal component is (22.9 ± 1.4) Gg CH4/month. By identifying a clear relationship between CH4 emissions and natural gas consumption, our results provide strong constraints on the pathways for fugitive CH4 emissions from the natural gas distribution system in Los Angeles. Key Points: A mountaintop remote sensing spectrometer is used to derive the time series and spatial pattern of methane emissions in LA basinThe methane emissions in the LA basin are strongly correlated with the consumption of natural gas by residential and commercial consumersAbout (1.4 ± 0.1)% of the residential and commercial natural gas consumption in LA is released into the atmosphere [ABSTRACT FROM AUTHOR]

This paper asks the question – who moves into what kinds of neighbourhoods and what kind of residential sorting is occurring in the ethnically diverse metropolitan region of Los Angeles. The study examines residential selections across a typology of neighbourhood types in the Los Angeles metropolitan region using residential mobility data from the Los Angeles Family and Neighborhood Survey (LAFANS). Similar to recent work in the UK and Canadian contexts, ethnic groups demonstrate moderately strong relationships between their socio‐economic statuses and their neighbourhood contexts. Both behaviour, that is, actual moves and preferences, are consistent with a tendency to increased mixing and declining segregation in the residential mosaic. In particular, the expressed residential preferences and the choices of these households provide an explanatory context for the overall decline in segregation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the influence of six psychographic variables (materialism, novelty seeking, personal gratification, status consumption, value consciousness, and integrity) and three demographic variables (age, gender, and income) on attitude and purchase intention toward counterfeit apparel within the ports of Los Angeles and Long Beach. A paper‐based survey method was used with a convenience sample of college students at a large university in Los Angeles County. A total of 118 usable responses were obtained. Results of two separate sets of multiple regression analyses showed a significant and positive influence of attitude on purchase intention of counterfeit apparel. Value consciousness and integrity were negatively related to the purchase intention. Results also showed that men and people in the lower income range had more positive purchase intention toward counterfeit apparel. Implications for future research were also discussed. [ABSTRACT FROM AUTHOR]

Coronavirus 2019 (COVID‐19) captured worldwide attention as the virus spread from initial detection as a pneumonia of unknown cause in Wuhan, China in December 2019 to the declaration of a pandemic by the WHO only 3 months later. This paper describes the impact of COVID‐19 on cardiac surgery services in the greater Los Angeles area. Discussion includes public health response to the pandemic, how local hospitals reacted to the expected surge in patients with COVID, the establishment of telemedicine services, and the projected future impact on California healthcare as a result of the COVID‐19 pandemic. [ABSTRACT FROM AUTHOR]

High solar photovoltaic (PV) penetration in the electrical grid can result in undesired effects on the voltage quality, leading to line loss and voltage magnitude increases. One of the main criteria to ensure the safe penetration of high-power solar systems in the main grid is maintaining an acceptable voltage magnitude when a disturbance occurs (e.g., 0.95 and 1.05 per unit) with respect to total installed power generation capacity of PV power plants. This manuscript analyzes the effects of high solar PV penetration per unit of voltage stability using the Fast Voltage Stability Index and total power loss. Moreover, we investigate the flexibility benefits of coordinated voltage control based on a smart inverter of solar PV capacitor banks (SI-CBs) under five cases in a typical microgrid (MG) test model. For the test of the SI-CBs, MG modeling is developed on a modified IEEE 123 test feeder, which includes 11 building load solar PVs with smart inverters and capacitor banks with real-time data from an area in Los Angeles, California, USA. The simulation results are presented to validate the effectiveness of the proposed approach using a real-time MATLAB interface to the Open Distribution System Simulator (OpenDSS). [ABSTRACT FROM AUTHOR]

Different from the western classical stone buildings, China has formed the traditional architectural style with wood as the main body since ancient times. With the progress of the times and the collision between Chinese and western cultures, people put forward higher requirements for the current urban planning and landscape design, hoping that the future urban landscape design can follow the style of "Chinese and new." Traditional urban landscape design usually adopts solid model, rendering renderings, or three-dimensional animation, but these methods all have some defects. With the development of computer technology and the rise of Internet industry, virtual reality technology appears, and because of its excellent multiperception, immersion, interactivity, and autonomy, it is gradually applied to medical, military, entertainment, virtual city, and other fields of human life. Urban landscape design based on virtual reality technology is an important technical way of urban landscape design at present. It can help designers to better perfect the design details, experience it personally in the design process, find the existing problems and defects in the current design in time, and improve the design efficiency. It can also assist urban planners to make corresponding decisions. However, due to the high cost and the shortage of technical personnel, it is only implemented in a small area at present. Take the virtual Los Angeles project in the United States as an example, which is a typical case of the application of virtual reality technology in urban planning and construction and successfully realizes the interactive function between users and virtual environment. With the continuous development and improvement of virtual reality technology, there are more and more corresponding talents, and this technology will be widely used in the future urban planning and construction, forming our own "middle and new" urban landscape style. [ABSTRACT FROM AUTHOR]

Relying on data from the United States Census and the American Time Use Survey (2010–2017), we examine how residential segregation influences per capita discretionary time availability in Los Angeles, New York City and Miami. We find a sizable disadvantage of being Latinx for discretionary time availability. Non‐Latinx Whites have 182 extra hours of per capita discretionary time per year than do Latinx individuals. Both within‐neighbourhood and adjacent‐neighbourhood influences matter. In most neighbourhoods, segregation is correlated with having more discretionary time. Individuals in highly segregated areas have approximately 80 more hours of discretionary time per year than those living in diverse areas. This suggests that in addition to socioeconomic, cultural and well‐being benefits, ethnic enclaves may also impart temporal advantages. However, we find that there may be diminishing marginal returns with increasing segregation in surrounding areas. Sociodemographic characteristics explain over one‐quarter of the variance between segregation and discretionary time availability. [ABSTRACT FROM AUTHOR]

We examine how the decay of high‐frequency amplitudes of Fourier spectra of strong earthquake ground acceleration (described in seismological literature by the slope parameter κ $\kappa $) depends on the soil and geological site conditions at the recording stations in the Los Angeles metropolitan area. Then, we introduce a Gedanken numerical experiment, in which we analyze nonlinear wave motion in shallow soil and show that it also leads to similar decay of the high‐frequency spectral amplitudes. The results of both of our studies are consistent with the interpretation that the decay of high‐frequency Fourier spectra of strong motion acceleration, described by κ $\kappa $, occurs at the recording site near the ground surface. [ABSTRACT FROM AUTHOR]

Solar photovoltaics (PV) are a renewable electricity technology with lower carbon dioxide equivalent (CO2e) impacts compared to fossil electricity, making it a technology of interest with respect to combatting global climate change. This paper combines agent‐based modeling (ABM) with life cycle assessment (LCA) to simulate rooftop solar PV adoption in Los Angeles (LA) County from 2018–2050 and generate CO2e impact data at the societal level to compare PV and grid electricity. With respect to solar PV panels, consumer adoption is the "pull" that moves the system and corresponding life cycle CO2e impacts forward. ABM is used to evaluate the impact of policies and evolutions in technology regarding the adoption of solar PV. Life cycle assessment is used to quantify the life cycle CO2e impacts of solar PV (including raw materials, manufacturing, and use). The results show that scenarios that increase PV adoption also increase the CO2e impacts from solar PV use in the short term, due to the raw materials and manufacturing portions of the life cycle. Yet, in the long term, adoption of solar PV may provide CO2e impact savings from offsetting grid electricity (although this is dependent on the carbon intensity of the electricity sources). The CO2e impacts of solar panels are dominated by the raw materials and manufacturing phases on a product level basis, but the use phase contributes to the majority of environmental impact savings from an adoption and societal‐level perspective. Future work may apply the methodology to other locations in the United States to evaluate if solar panels are an advantageous electricity source compared to the environmental impacts of the electricity grid. Integr Environ Assess Manag 2020;16:1008–1018. © 2020 SETAC KEY POINTS: Residential solar PV has the potential to be adopted at an increasing rate due to a variety of policy and market incentives.The environmental impact of manufacturing solar PV is relatively low compared to its potential to save GHG emissions during the use phase.Coupling agent based modeling and life cycle assessment results have the potential to yield new insights. [ABSTRACT FROM AUTHOR]

SUMMARY This paper presents the motivation and the mathematics required for the introduction of Bayesian structural reliability theory into the process of evaluating and strengthening any tall building located in the Los Angeles region. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The amygdala and its connections with medial prefrontal cortex (mPFC) play central roles in the development of emotional processes. While several studies have suggested that this circuitry exhibits functional changes across the first two decades of life, findings have been mixed ‐ perhaps resulting from differences in analytic choices across studies. Here we used multiverse analyses to examine the robustness of task‐based amygdala—mPFC function findings to analytic choices within the context of an accelerated longitudinal design (4–22 years‐old; N = 98; 183 scans; 1–3 scans/participant). Participants recruited from the greater Los Angeles area completed an event‐related emotional face (fear, neutral) task. Parallel analyses varying in preprocessing and modeling choices found that age‐related change estimates for amygdala reactivity were more robust than task‐evoked amygdala—mPFC functional connectivity to varied analytical choices. Specification curves indicated evidence for age‐related decreases in amygdala reactivity to faces, though within‐participant changes in amygdala reactivity could not be differentiated from between‐participant differences. In contrast, amygdala—mPFC functional connectivity results varied across methods much more, and evidence for age‐related change in amygdala—mPFC connectivity was not consistent. Generalized psychophysiological interaction (gPPI) measurements of connectivity were especially sensitive to whether a deconvolution step was applied. Our findings demonstrate the importance of assessing the robustness of findings to analysis choices, although the age‐related changes in our current work cannot be overinterpreted given low test–retest reliability. Together, these findings highlight both the challenges in estimating developmental change in longitudinal cohorts and the value of multiverse approaches in developmental neuroimaging for assessing robustness of results. [ABSTRACT FROM AUTHOR]

By "thinking conjuncturally", this article urges urban geographers to rethink the site of encampments as a space for cultural intervention in urban planning and development. Drawing on content analysis of archival records, this article provides a case study of Black‐led and supported encampment communities in the 1980s and 1990s in Los Angeles. These encampment communities emerged in a critical moment when Los Angeles became the homeless capital of the nation while the demographics of the homeless became predominantly Black. The article shows the emergence of encampment communities as both a result of rising homelessness and as a necessity for creating life‐fulfilling alternatives. As such, these include sonic critiques, cooperative planning, forming a commons, and a poetic ethnography against the carceral organisation of homelessness. The article shows that to understand homelessness and crisis, geographers must take seriously the site of the encampment as an emerging cultural intervention. [ABSTRACT FROM AUTHOR]

Background and Objectives: While inadequate nutrition can weaken the immune system and lead to negative health sequelae for vulnerable populations, little is known about nutritional intake among people who inject drugs (PWID). We aimed to quantify nutritional intake among PWID and to explore associations between protein intake and drug use. Methods: A cross‐sectional design was used to analyze self‐reported participant data. PWID were recruited from community settings in California in 2016/2017. Participants reported on food consumption per day for a 30‐day period, from which a continuous protein intake variable was created. Results: Modal characteristics of participants (N = 937) were: white (42.5%), male (75.3%), healthy body mass index (BMI) (56.6%), and unhoused (82.9%). Less than 1% of participants met or exceeded recommended guidelines for protein intake (0.80 g/day/1 kg body weight). The final multiple regression model found protein intake to be significantly positively associated with older age, high school or greater education, frequency of opiate and marijuana use, while Latinx ethnicity was inversely associated with protein intake, adjusting for gender. Discussion and Conclusions: Our study shows PWID are generally not underweight, yet they are grossly protein deficient, which can be harder to recognize. Poverty, homelessness, and other structural barriers likely contribute to this issue, which demonstrates the need for communities to provide more access to nutrient‐rich food to PWID. Scientific Significance: Our study demonstrates the novel findings that opiate and marijuana use frequency, but not stimulants (methamphetamine and cocaine) may increase preference for protein‐rich foods among PWID. [ABSTRACT FROM AUTHOR]

Voter mobilization by unions has garnered some attention from scholars, and is seen as an important political tool. Unions often mobilize voters repeatedly across several campaigns; however, the literature treats mobilization as a singular event. This paper empirically analyzes turnout of 85,064 registered voters over 14 months at five election intervals in Los Angeles, exploring whether union-led mobilization is subject to diminishing returns across multiple elections. Results indicate that diminishing returns occur; three or more contacts are no more beneficial than one or two. Contact in recent elections is more effective than distant contact, and results differ slightly by contact type. [ABSTRACT FROM AUTHOR]

Background: Despite mandated insurance coverage for breast reconstruction following mastectomy, health care costs are increasingly passed on to women through cost‐sharing arrangements and high‐deductible health plans. In this population‐based study, the authors assessed perceived financial and employment declines related to breast reconstruction following mastectomy. Methods: Women with early‐stage breast cancer (stages 0‐II) diagnosed between July 2013 and May 2015 who underwent mastectomy were identified through the Surveillance, Epidemiology, and End Results registries of Georgia and Los Angeles and were surveyed. Primary outcome measures included patients' appraisal of their financial and employment status after cancer treatment. Multivariable models evaluated the association between breast reconstruction and primary outcomes. Results: Among 883 patients with breast cancer who underwent mastectomy, 44.2% did not undergo breast reconstruction, and 55.8% underwent reconstruction. Overall, 21.9% of the cohort reported being worse off financially since their diagnosis (25.8% with reconstruction vs 16.6% without reconstruction; P =.002). Women who underwent reconstruction reported higher out‐of‐pocket medical expenses (32.1% vs 15.6% with expenses greater than $5000; P <.001). Reconstruction was independently associated with a perceived decline in financial status (odds ratio, 1.92; 95% confidence interval, 1.15‐3.22; P =.013). Among women who were employed at the time of their diagnosis, there was no association between reconstruction and a perceived decline in employment status (P =.927). Conclusions: In this diverse cohort of women who underwent mastectomy, those who elected to undergo reconstruction experienced higher out‐of‐pocket medical expenses and self‐reported financial decline. Patients, providers, and policymakers should be aware of the potential financial implications related to reconstruction despite mandatory insurance coverage. Among 883 patients with breast cancer who underwent mastectomy, women who underwent reconstruction reported higher out‐of‐pocket medical expenses and were independently more likely to report a perceived decline in their financial status. Patients, providers, and policymakers should be aware of the potential financial implications related to reconstruction despite mandatory insurance coverage. [ABSTRACT FROM AUTHOR]

Anna Neimark is a founding partner of First Office, an architectural firm based in Los Angeles. Here she describes a recent exhibition design for Eugène Trutat's photographs, and the installation inspired by them that was created at Sci‐Arc in 2020. The exhibition is both a simple display of Trutat's work and a contemporary take on his influence on what she refers to as 'Rude Form'. [ABSTRACT FROM AUTHOR]

How do you preserve the history of a neighbourhood undergoing change? How do you honour its residents and their legacy of lucha (struggle)? How do you uplift the voices of community members, students and researchers of colour in the museum world? In this joint reflection, members of the Los Angeles Boyle Heights Museum (BHM) reflect on their collaborative endeavours to research, preserve and celebrate the multi‐ethnic history of this Los Angeles (LA) neighbourhood. As a research, exhibition and educational project led by professors, graduate students, undergraduate students and community members, the BHM team uses a horizontal leadership model to uplift and tell the stories of a neighbourhood. The BHM team members discuss the various approaches they use to build confianza – trust – among themselves and within US Latinx migrant communities. By centring confianza as both a method and a theoretical framework for public history work, the team demonstrates how it builds a more inclusive, family‐centred and intergenerational museum experience. Through building confianza, the team has been able to pivot their work to address and manoeuvre new challenges during the Covid‐19 pandemic. [ABSTRACT FROM AUTHOR]