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Coastal herbivorous fishes consume macroalgae, which is then degraded by microbes along their digestive tract. However, there is scarce genomic information about the microbiota that perform this degradation. This study explores the potential of Kyphosus gastrointestinal microbial symbionts to collaboratively degrade and ferment polysaccharides from red, green, and brown macroalgae through in silico study of carbohydrate-active enzyme and sulfatase sequences. Recovery of metagenome-assembled genomes (MAGs) from previously described Kyphosus gut metagenomes and newly sequenced bioreactor enrichments reveals differences in enzymatic capabilities between the major microbial taxa in Kyphosus guts. The most versatile of the recovered MAGs were from the Bacteroidota phylum, whose MAGs house enzyme collections able to decompose a variety of algal polysaccharides. Unique enzymes and predicted degradative capacities of genomes from the Bacillota (genus Vallitalea) and Verrucomicrobiota (order Kiritimatiellales) highlight the importance of metabolic contributions from multiple phyla to broaden polysaccharide degradation capabilities. Few genomes contain the required enzymes to fully degrade any complex sulfated algal polysaccharide alone. The distribution of suitable enzymes between MAGs originating from different taxa, along with the widespread detection of signal peptides in candidate enzymes, is consistent with cooperative extracellular degradation of these carbohydrates. This study leverages genomic evidence to reveal an untapped diversity at the enzyme and strain level among Kyphosus symbionts and their contributions to macroalgae decomposition. Bioreactor enrichments provide a genomic foundation for degradative and fermentative processes central to translating the knowledge gained from this system to the aquaculture and bioenergy sectors.IMPORTANCESeaweed has long been considered a promising source of sustainable biomass for bioenergy and aquaculture feed, but scalable i

Marine herbivorous fish that feed primarily on macroalgae, such as those from the genus Kyphosus, are essential for maintaining coral health and abundance on tropical reefs. Here, deep metagenomic sequencing and assembly of gut compartment-specific samples from three sympatric, macroalgivorous Hawaiian kyphosid species have been used to connect host gut microbial taxa with predicted protein functional capacities likely to contribute to efficient macroalgal digestion. Bacterial community compositions, algal dietary sources, and predicted enzyme functionalities were analyzed in parallel for 16 metagenomes spanning the mid- and hindgut digestive regions of wild-caught fishes. Gene colocalization patterns of expanded carbohydrate (CAZy) and sulfatase (SulfAtlas) digestive enzyme families on assembled contigs were used to identify likely polysaccharide utilization locus associations and to visualize potential cooperative networks of extracellularly exported proteins targeting complex sulfated polysaccharides. These insights into the gut microbiota of herbivorous marine fish and their functional capabilities improve our understanding of the enzymes and microorganisms involved in digesting complex macroalgal sulfated polysaccharides. IMPORTANCE This work connects specific uncultured bacterial taxa with distinct polysaccharide digestion capabilities lacking in their marine vertebrate hosts, providing fresh insights into poorly understood processes for deconstructing complex sulfated polysaccharides and potential evolutionary mechanisms for microbial acquisition of expanded macroalgal utilization gene functions. Several thousand new marine-specific candidate enzyme sequences for polysaccharide utilization have been identified. These data provide foundational resources for future investigations into suppression of coral reef macroalgal overgrowth, fish host physiology, the use of macroalgal feedstocks in terrestrial and aquaculture animal feeds, and the bioconversion of macro

Historically, Hawai'i had few massive coral bleaching events, until two consecutive heatwaves in 2014-2015. Consequent mortality and thermal stress were observed in Kāne'ohe Bay (O'ahu). The two most dominant local species exhibited a phenotypic dichotomy of either bleaching resistance or susceptibility (Montipora capitata and Porites compressa), while the third predominant species (Pocillopora acuta) was broadly susceptible to bleaching. In order to survey shifts in coral microbiomes during bleaching and recovery, 50 colonies were tagged and periodically monitored. Metabarcoding of three genetic markers (16S rRNA gene ITS1 and ITS2) followed by compositional approaches for community structure analysis, differential abundance and correlations for longitudinal data were used to temporally compare Bacteria/Archaea, Fungi and Symbiodiniaceae dynamics. P. compressa corals recovered faster than P. acuta and Montipora capitata. Prokaryotic and algal communities were majorly shaped by host species, and had no apparent pattern of temporal acclimatization. Symbiodiniaceae signatures were identified at the colony scale, and were often related to bleaching susceptibility. Bacterial compositions were practically constant between bleaching phenotypes, and more diverse in P. acuta and M. capitata. P. compressa's prokaryotic community was dominated by a single bacterium. Compositional approaches (via microbial balances) allowed the identification of fine-scale differences in the abundance of a consortium of microbes, driving changes by bleaching susceptibility and time across all hosts. The three major coral reef founder-species in Kāne'ohe Bay revealed different phenotypic and microbiome responses after 2014-2015 heatwaves. It is difficult to forecast, a more successful strategy towards future scenarios of global warming. Differentially abundant microbial taxa across time and/or bleaching susceptibility were broadly shared among all hosts, suggesting that locally, the same microb

One mechanism giving fleshy algae a competitive advantage over corals during reef degradation is algal-induced and microbially-mediated hypoxia (typically less than 69.5 µmol oxygen L−1). During hypoxic conditions oxygen availability becomes insufficient to sustain aerobic respiration in most metazoans. Algae are more tolerant of low oxygen conditions and may outcompete corals weakened by hypoxia. A key question on the ecological importance of this mechanism remains unanswered: How extensive are local hypoxic zones in highly turbulent aquatic environments, continuously flushed by currents and wave surge? To better understand the concert of biological, chemical, and physical factors that determine the abundance and distribution of oxygen in this environment, we combined 3D imagery, flow measurements, macro- and micro-organismal abundance estimates, and experimentally determined biogenic oxygen and carbon fluxes as input values for a 3D bio-physical model. The model was first developed and verified for controlled flume experiments containing coral and algal colonies in direct interaction. We then developed a three-dimensional numerical model of an existing coral reef plot off the coast of Curaçao where oxygen concentrations for comparison were collected in a small-scale grid using fiberoptic oxygen optodes. Oxygen distribution patterns given by the model were a good predictor for in situ concentrations and indicate widespread localized differences exceeding 50 µmol L-1 over distances less than a decimeter. This suggests that small-scale hypoxic zones can persist for an extended period of time in the turbulent environment of a wave- and surge- exposed coral reef. This work highlights how the combination of three-dimensional imagery, biogenic fluxes, and fluid dynamic modeling can provide a powerful tool to illustrate and predict the distribution of analytes (e.g., oxygen or other bioactive substances) in a highly complex system.

Background: Although women with polycystic kidney disease (PKD) generally have healthy pregnancies and babies, pregnancy is associated with a greater risk of maternal complications and requires planning and management of their condition. Given these possible complications, routine communication about childbearing between women with PKD and their treating team is important. A question prompt list (QPL), a structured list of questions used by patients during consultations with healthcare providers, may be beneficial in assisting women with PKD to discuss their childbearing concerns with, and seek related information from, their treating team. The aims of this study were to co‐design a QPL about pregnancy and childbearing for women with PKD, and evaluate its comprehensibility, salience, and acceptability. Methods: An exploratory sequential mixed‐methods study of women of reproductive age with PKD living in Australia, using an experience‐based co‐design approach with two phases. Women were recruited from a metropolitan public health service and via social media and invited to complete an anonymous online survey about the development of the PKD QPL (phase one) and participate in an online discussion group about its refinement (phase two). Results: Sixteen women completed the development survey and seven participated in the evaluation discussion group. Participants reported that women with PKD would value and use a QPL to prompt discussions with and seek further information about pregnancy and childbearing from their healthcare providers. Women identified four main topics for the QPL: ‘thinking about having a baby’, ‘pregnancy’, ‘my medications’ and ‘after my baby is born’. Within each section a series of questions was developed. Based on the findings, a QPL about pregnancy and childbearing for women with PKD was co-designed. Conclusions: Women with PKD often find it difficult to access information and have discussions with their health care providers about pregnancy a

Metabolites exuded by primary producers comprise a significant fraction of marine dissolved organic matter, a poorly characterized, heterogenous mixture that dictates microbial metabolism and biogeochemical cycling. We present a foundational untargeted molecular analysis of exudates released by coral reef primary producers using liquid chromatography-tandem mass spectrometry to examine compounds produced by two coral species and three types of algae (macroalgae, turfing microalgae, and crustose coralline algae [CCA]) from Moorea, French Polynesia. Of 10,568 distinct ion features recovered from reef and mesocosm waters, 1,667 were exuded by producers; the majority (86%) were organism specific, reflecting a clear divide between coral and algal exometabolomes. These data allowed us to examine two tenets of coral reef ecology at the molecular level. First, stoichiometric analyses show a significantly reduced nominal carbon oxidation state of algal exometabolites than coral exometabolites, illustrating one ecological mechanism by which algal phase shifts engender fundamental changes in the biogeochemistry of reef biomes. Second, coral and algal exometabolomes were differentially enriched in organic macronutrients, revealing a mechanism for reef nutrient-recycling. Coral exometabolomes were enriched in diverse sources of nitrogen and phosphorus, including tyrosine derivatives, oleoyl-taurines, and acyl carnitines. Exometabolites of CCA and turf algae were significantly enriched in nitrogen with distinct signals from polyketide macrolactams and alkaloids, respectively. Macroalgal exometabolomes were dominated by nonnitrogenous compounds, including diverse prenol lipids and steroids. This study provides molecular-level insights into biogeochemical cycling on coral reefs and illustrates how changing benthic cover on reefs influences reef water chemistry with implications for microbial metabolism.

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Remple, K. L., Silbiger, N. J., Quinlan, Z. A., Fox, M. D., Kelly, L. W., Donahue, M. J., & Nelson, C. E. Coral reef biofilm bacterial diversity and successional trajectories are structured by reef benthic organisms and shift under chronic nutrient enrichment. Npj Biofilms and Microbiomes, 7(1), (2021): 84, https://doi.org/10.1038/s41522-021-00252-1., Work on marine biofilms has primarily focused on host-associated habitats for their roles in larval recruitment and disease dynamics; little is known about the factors regulating the composition of reef environmental biofilms. To contrast the roles of succession, benthic communities and nutrients in structuring marine biofilms, we surveyed bacteria communities in biofilms through a six-week succession in aquaria containing macroalgae, coral, or reef sand factorially crossed with three levels of continuous nutrient enrichment. Our findings demonstrate how biofilm successional trajectories diverge from temporal dynamics of the bacterioplankton and how biofilms are structured by the surrounding benthic organisms and nutrient enrichment. We identify a suite of biofilm-associated bacteria linked with the orthogonal influences of corals, algae and nutrients and distinct from the overlying water. Our results provide a comprehensive characterization of marine biofilm successional dynamics and contextualize the impact of widespread changes in reef community composition and nutrient pollution on biofilm community structure., This work was supported through grants from the National Science Foundation for Biological Oceanography (1923877 to C.E.N. and M.J.D., 1949033 to C.E.N. and 2118687 to L.W.K., and 1924281 to N.J.S.) and the National Fish and Wildlife Foundation (grant no. 44447 to C.E.N.). This paper is funded in part by the National Oceanic and Atmospheric Administration, Project A/AS-1, which is sponsored by the University of Hawaii Sea Grant College Program, SOEST, under Institutional Grant No. NA18OAR4170076 from NOAA Office of Sea Grant, Department of Commerce. This is CSUN marine biology contribution #365, UH Sea Grant contribution UNIHI-SEAGRANT-JC-21-06, and UH SOEST contribution 11435.

Work on marine biofilms has primarily focused on host-associated habitats for their roles in larval recruitment and disease dynamics; little is known about the factors regulating the composition of reef environmental biofilms. To contrast the roles of succession, benthic communities and nutrients in structuring marine biofilms, we surveyed bacteria communities in biofilms through a six-week succession in aquaria containing macroalgae, coral, or reef sand factorially crossed with three levels of continuous nutrient enrichment. Our findings demonstrate how biofilm successional trajectories diverge from temporal dynamics of the bacterioplankton and how biofilms are structured by the surrounding benthic organisms and nutrient enrichment. We identify a suite of biofilm-associated bacteria linked with the orthogonal influences of corals, algae and nutrients and distinct from the overlying water. Our results provide a comprehensive characterization of marine biofilm successional dynamics and contextualize the impact of widespread changes in reef community composition and nutrient pollution on biofilm community structure.

Dataset: EOF and benthic community Oahu, Empirical orthogonal functions (EOFs) and benthic communities at Wailupe and Black Point on Oahu, Hawai'i. Full methods describing this dataset are found in La Valle et al. 2020 (doi:10.1002/lno.11596) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/860764, NSF Division of Ocean Sciences (NSF OCE) OCE-1923877

Bacterioplankton consume about half of the dissolved organic matter (DOM) produced by phytoplankton. DOM released from phytoplankton consists of a myriad of compounds that span a range of biological reactivity from labile to recalcitrant. Linking specific bacterioplankton lineages to the incorporation of DOM compounds into biomass is important to understand microbial niche partitioning. We conducted a series of DNA-stable isotope probing (SIP) experiments using 13C-labeled substrates of varying lability including amino acids, cyanobacteria lysate, and DOM from diatom and cyanobacteria isolates concentrated on solid phase extraction PPL columns (SPE-DOM). Amendments of substrates into Sargasso Sea bacterioplankton communities were conducted to explore microbial response and DNA-SIP was used to determine which lineages of Bacteria and Archaea were responsible for uptake and incorporation. Greater increases in bacterioplankton abundance and DOC removal were observed in incubations amended with cyanobacteria-derived lysate and amino acids compared to the SPE-DOM, suggesting that the latter retained proportionally more recalcitrant DOM compounds. DOM across a range of bioavailability was utilized by diverse prokaryotic taxa with copiotrophs becoming the most abundant 13C-incorporating taxa in the amino acid treatment and oligotrophs becoming the most abundant 13C-incorporating taxa in SPE-DOM treatments. The lineages that responded to SPE-DOM amendments were also prevalent in the mesopelagic of the Sargasso Sea, suggesting that PPL extraction of phytoplankton-derived DOM isolates compounds of ecological relevance to oligotrophic heterotrophic bacterioplankton. Our study indicates that DOM quality is an important factor controlling the diversity of the microbial community response, providing insights into the roles of different bacterioplankton in resource exploitation and efficiency of marine carbon cycling.

We sought to resolve the extent, variability, and magnitude of productivity enrichment around a high tropical island consistent with the phenomenon of an Island Mass Effect (IME). Key biogeochemical constituents and physical oceanographic parameters were measured offshore over the upper 500 m from July 27 to August 7, 2014 around the Society Island of Mo'orea in French Polynesia in association with the nearshore measurements of the Mo'orea Coral Reef Long Term Ecological Research program. High-resolution synoptic sampling in a rectangular grid around the island revealed vertical and horizontal patterns in hydrographic conditions, inorganic nutrients, rates of productivity, and concentrations of organic matter that are characteristic of oligotrophic gyre ecosystems. Within the upper euphotic zone (0-75 m), levels of net primary productivity (NPP), chlorophyll a (Chl), heterotrophic bacterioplankton productivity (BP), and particulate organic carbon (POC) exhibited concurrent enhancement at stations located within 5-15 km of shore, relative to stations farther offshore. These observations of enhanced productivity near an island are consistent with an IME. Particulate organic matter nitrogen isotopes (POM-delta N-15) were significantly lower near the island than at stations farther offshore, further emphasizing spatial differences in water column biogeochemistry consistent with an IME. Vertical profiles suggest thermocline shoaling and mixing associated with the pycnocline impinging on the island's submerged flanks and coral reef slope may have contributed to the decreasing depth and increasing intensity of chlorophyll-a concentration in the DCM at nearshore stations relative to farther offshore. Shipboard measurements of an anticyclonic flow within the upper 75 m of the water column in the vicinity of Mo'orea suggest that retention of inorganic nutrients and organic matter near Mo'orea may also have contributed to the patterns in NPP, Chl, BP, POC, and POM-delta N-15

Dataset: Benthic macroalgal carbon uptake rates, Benthic macroalgal and water column carbon uptake rates in an experimental chamber, Maunalua, O’ahu, Hawai’i, 2015-2016. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/822216, NSF Division of Ocean Sciences (NSF OCE) OCE-1538393

Dataset: C and N isotopes, Carbon and Nitrogen isotopes in an experimental benthic chamber, Maunalua, O’ahu, Hawai’i, 2015-2016 For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/822239, NSF Division of Ocean Sciences (NSF OCE) OCE-1538393

Crustose coralline algae (CCA) are critical members of the coral reef ecosystem, yet they remain poorly studied. Recent research on CCA has shown that only a few species play a significant role in the settlement of coral larvae through either the production of chemical settlement cues or the facilitation of specific microbial communities that are hypothesized to influence coral settlement. Thus, defining how DOM exudates differ between CCA species and the bacterioplankton communities these exudates facilitate is important for understanding the role of CCA in invertebrate settlement. We conducted single day exudation experiments on two species of CCA to compare tissue microbiome community structure, DOM production and the effect of DOM on the bacterioplankton community. We collected exudates from Hydrolithon reinboldii and Porolithon onkodes in both filter-sterilized seawater and unfiltered seawater from Kāneohe Bay, Hawaii. Our results demonstrate that while both species exude equivalent quantities of dissolved organic carbon they differ in the composition of fluorescent DOM and fostered distinct microbial communities. P. onkodes exudates facilitate more microbial OTUs associated with coral disease, whereas H. reinboldii facilitated OTUs known to produce antimicrobial compounds. Our results highlight species-specific differences in the composition of fDOM exudates of CCA and the effect of those on microbial community structure.

On coral reefs, microorganisms are essential for recycling nutrients to primary producers through the remineralization of benthic-derived organic matter. Diel investigations of reef processes are required to holistically understand the functional roles of microbial players in these ecosystems. Here we report a metagenomic analysis characterizing microbial communities in the water column overlying 16 remote forereef sites over a diel cycle. Our results show that microbial community composition is more dissimilar between day and night samples collected from the same site than between day or night samples collected across geographically distant reefs. Diel community differentiation is largely driven by the flux of Psychrobacter sp., which is two-orders of magnitude more abundant during the day. Nighttime communities are enriched with species of Roseobacter, Halomonas, and Alteromonas encoding a greater variety of pathways for carbohydrate catabolism, further illustrating temporal patterns of energetic provisioning between different marine microbes. Dynamic diel fluctuations of microbial populations could also support the efficient trophic transfer of energy posited in coral reef food webs.

Dataset: Hawaiian crustose coralline algae dissolved organic matter, Fluorescent characteristics of the dissolved organic exudates of two species of crustose coralline algae (Hydrolithon reinboldii and Porolithon onkodes) in two water treatments (pre-filtered and unfiltered) and their effect on the microbial community cell count. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/783581, NSF Division of Ocean Sciences (NSF OCE) OCE-1538393

Dataset: Event logs: MCR10-1 and MCR11-1, Scientific sampling event logs recorded during the MCR10-1 cruise/trip (the Coral DOM 2010 Research Campaign) and the MCR11-1 cruise/trip (the Coral DOM 2011 Research Campaign) at the Richard B Gump Research Station at the Moorea Coral Reef LTER site. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3684, NSF Division of Ocean Sciences (NSF OCE) OCE-0927411

Dataset: CRANE: fDOM, DOC, and TP, Concentrations of colored dissolved organic matter, dissolved organic carbon, and total phosphorous from experiments conducted at the University of Hawaii, Manoa in 2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/723868, NSF Division of Ocean Sciences (NSF OCE) OCE-1538393

ObjectiveUse latent class analysis (LCA) to identify patterns of cognitive functioning in a sample of older adults with clinical depression and without dementia and assess demographic, psychiatric, and neurobiological predictors of class membership.MethodNeuropsychological assessment data from 121 participants in the Alzheimer's Disease Neuroimaging Initiative-Depression project (ADNI-D) were analyzed, including measures of executive functioning, verbal and visual memory, visuospatial and language functioning, and processing speed. These data were analyzed using LCA, with predictors of class membership such as depression severity, depression and treatment history, amyloid burden, and APOE e4 allele also assessed.ResultsA two-class model of cognitive functioning best fit the data, with the Lower Cognitive Class (46.1% of the sample) performing approximately one standard deviation below the Higher Cognitive Class (53.9%) on most tests. When predictors of class membership were assessed, carrying an APOE e4 allele was significantly associated with membership in the Lower Cognitive Class. Demographic characteristics, age of depression onset, depression severity, history of psychopharmacological treatment for depression, and amyloid positivity did not predict class membership.ConclusionLCA allows for identification of subgroups of cognitive functioning in a mostly cognitively intact late life depression (LLD) population. One subgroup, the Lower Cognitive Class, more likely to carry an APOE e4 allele, may be at a greater risk for subsequent cognitive decline, even though current performance on neuropsychological testing is within normal limits. These findings have implications for early identification of those at greatest risk, risk factors, and avenues for preventive intervention.

Climate change is warming the oceans, increasing carbon dioxide partial pressure and reducing nutrient recycling from deep layers. This will affect carbon (C) and phosphorus (P) availability in the oceans, thus, altering the balance between the nutrient content of consumers and their food resource. The combined effects of food quality and temperature have been investigated for adult copepods; however, nauplii, the early developmental stages of copepods, often far outnumber adults, grow more rapidly and have a higher phosphorus body content and demand than later life stages. Consequently, ontogeny may affect how copepods respond to the combined stressors of increasing temperature and altered food stoichiometry. We conducted temperature-controlled experiments (24, 28 and 32 A degrees C) where Parvocalanus crassirostris was fed either a P-replete or a P-limited phytoplankton food source. Reduced survival of nauplii and copepodites at the highest temperature was ameliorated when fed P-replete food. At higher temperatures, copepodite growth remained stable, but internal C:P stoichiometry diverged in the direction of phytoplankton C:P, suggesting that increased temperature affected copepodite stoichiometric homeostasis. In contrast, naupliar P content increased with temperature and naupliar growth was P limited, suggesting nauplii required additional phosphorus at higher temperatures. We conclude that resource stoichiometry plays a key role in how copepod survival and growth are impacted by temperature, and that ontogeny mediates these responses. Our results suggest that as the extent of warming oceans and phytoplankton nutrient limitation increase, copepod survival and the growth of early life stages may decline.

Primers targeting the 16S small subunit ribosomal RNA marker gene, used to characterize bacterial and archaeal communities, have recently been re-evaluated for marine planktonic habitats. To investigate whether primer selection affects the ecological interpretation of bacterioplankton populations and community dynamics, amplicon sequencing with four primer sets targeting several hypervariable regions of the 16S rRNA gene was conducted on both mock communities constructed from cloned 16S rRNA genes and a time-series of DNA samples from the temperate coastal Santa Barbara Channel. Ecological interpretations of community structure (delineation of depth and seasonality, correlations with environmental factors) were similar across primer sets, while population dynamics varied. We observed substantial differences in relative abundances of taxa known to be poorly resolved by some primer sets, such as Thaumarchaeota and SAR11, and unexpected taxa including Roseobacter clades. Though the magnitude of relative abundances of common OTUs differed between primer sets, the relative abundances of the OTUs were nonetheless strongly correlated. We do not endorse one primer set but rather enumerate strengths and weaknesses to facilitate selection appropriate to a system or experimental goal. While 16S rRNA gene primer bias suggests caution in assessing quantitative population dynamics, community dynamics appear robust across studies using different primers.

ObjectivesTo investigate the association between cognitive decline and cortical atrophy in individuals with mild cognitive impairment (MCI) and chronic subsyndromal symptoms of depression (SSD) over a 4-year period.DesignProspective cohort study.SettingMulticenter, clinic-based.ParticipantsWithin the Alzheimer's Disease Neuroimaging Initiative repository, the Neuropsychiatric Inventory was used to identify individuals with MCI and stable endorsement (SSD group N = 32) or no endorsement (non-SSD group N = 69) of depressive symptoms across time points.MeasurementsRepeated measures of cognitive outcomes, cortical atrophy, and their associations were evaluated with mixed effects models adjusting for age, education, sex, and APOE genotype.ResultsThe SSD group demonstrated accelerated decline on measures of global cognition (Alzheimer Disease Assessment Scale; df = 421, t = 2.242, p = 0.025), memory (Wechsler Memory Scale-Revised Logical Memory II; df = 244, t = -2.525, p = 0.011), information processing speed (Trail Making Test Parts A [df = 421, t = 2.376, p = 0.018] and B [df = 421, t = 2.533, p = 0.012]), and semantic fluency (Category Fluency; df = 424, t = -2.418, p = 0.016), as well as accelerated frontal lobe (df = 341, t = -2.648, p = 0.008) and anterior cingulate (df = 341, t = -3.786, p < 0.001) atrophy. No group differences were observed for rate of decline on measures of attention, learning, and confrontation naming or for rate of atrophy in any other regions. Accelerated frontal lobe and anterior cingulate atrophy was associated with cognitive decline on measures of global cognition, information processing speed, and semantic fluency (all p < 0.05), but not memory.ConclusionsIndividuals with chronic SSD may represent an MCI subgroup that is highly vulnerable to accelerated cognitive decline, an effect that may be governed by frontal lobe and anterior cingulate atrophy.

ObjectiveLittle is known about key factors associated with use of mental health services across the life course. This study determined key socioeconomic, social support, psychiatric, and medical predictors of services use in younger, middle, and older age.Design, setting, participants, measurementsThe sample included 3,708 adults with DSM-IV-based mood, anxiety, and substance use disorders in the Collaborative Psychiatric Epidemiology Surveys. Key predictors of mental health services use for each age group were systematically determined by multivariable models, and exploratory analyses examining potential effect modification by race-ethnicity and sex were assessed by interaction terms. Statistical analyses included complex design-corrected and weighted logistic regression analyses that provide results generalizable to the United States.ResultsPsychiatric and medical issues such as prior suicidal behavior, comorbid psychiatric disorders, and perceived cognitive impairment increased odds of mental health services use in younger, middle, and older age. Chronic medical conditions also influenced services use in younger and older age, with their impact on use across age potentially modified by racial-ethnic disparities (p interaction = 0.01). Moreover, socioeconomic factors like marital status influenced use in middle and older age, where being divorced, separated, widowed, or never married encouraged use. The effect of marital status on use across age was also potentially modified by racial-ethnic disparities (p interaction = 0.02).ConclusionsKey socioeconomic, social support, psychiatric, and medical predictors uniquely influence use of mental health services across the life course. These findings will help inform efforts to encourage greater services use by adults across the life course in need of care.

There are more than 4000 lakes above 2500 m elevation in the Sierra Nevada of California. Recent developments in understanding of aquatic ecosystem function predict that metabolism and food web structure in these dilute, low-productivity lakes may be dominated by an active and diverse microbial community. The identity, activity, and importance of pelagic prokaryotic communities (bacterioplankton) in these ecosystems is little known, yet understanding the role of these organisms in lake metabolism and food web dynamics is critical to predicting the response of Sierra lakes to global change. This study combined range-wide surveys, multiannual seasonal monitoring, and experimental approaches to describe the biodiversity and biogeochemical role of bacterioplankton in high-elevation lakes of the Sierra Nevada. Particular attention was payed to determining the impacts of anthropogenic nutrient deposition and introduced salmonids on the structure and metabolism of microbial communities.Our results indicate an abundant, remarkably diverse, and metabolically active bacterioplankton community. A three-year study of Emerald Lake, a representative cirque lake in Sequoia National Park, provided estimates of more than 250 bacterial phylotypes exhibiting predictable patterns of community phenology in response to seasonal transitions. Bacterial densities averaged 1 billion cells per liter throughout the year, and estimates of bacterioplankton biomass averaged 40% of total pelagic biomass. Rates of bacterial production were comparable to rates of net primary production, ranging from 1% during fall phytoplankton blooms to nearly 500% during snowmelt when terrestrial inputs of dissolved organic matter were highest. Bacterial metabolic properties were coupled to larger ecosystem dynamics, with growth efficiencies correlated with rates of primary productivity.Phosphorus enrichment, but not nitrogen enrichment, produced rapid and sustained increases in bacterial production rates and prod

© 2014 John Wiley & Sons Ltd. We investigated the effects of a wildfire on stream physical, chemical and biological characteristics in a Mediterranean climate, comparing stream community structure and consumer resource use in burned versus unburned catchments in Santa Barbara County, CA, U.S.A. Canopy cover was lower and water temperature was higher in streams draining basins where the riparian vegetation burned than in streams in unburned basins or burned basins where riparian vegetation remained intact. Stream flow and suspended sediment concentrations during large post-fire storms and wet season nutrient levels were higher in burned than unburned catchments, with increased sedimentation after flood peaks. A year after fires, algal levels were highest in streams where riparian vegetation burned and lowest in streams in burned basins where the riparian canopy remained intact. In contrast, streams in burned basins had lower particulate organic matter, detritivore and predator levels than unburned basins, regardless of whether riparian vegetation burned. Where present, southern California steelhead trout (Oncorhynchus mykiss) were extirpated from burned basins. Algivore densities were high in streams with burned riparian vegetation for two post-fire years before declining to unburned stream levels. Shredder densities rebounded in streams in burned basins with intact riparian vegetation, but remained low for 4 years where riparian vegetation burned. Predatory invertebrate densities increased at sites where trout were eliminated by wildfire. Hydrogen stable isotope analysis indicated that the diets of most invertebrate taxa in streams with burned riparian vegetation a year after fires were comprised of a higher proportion of algal material than riparian detritus relative to invertebrates in streams with intact riparian vegetation. Wildfire impacts on stream food webs are determined, in part, by fire severity in the riparian zone. Streams with burned riparian canopi

Stable isotope analyses (SIA) are an increasingly useful tool for understanding functional links between water flow and nutrient cycling over coral reefs, including relative fluxes of oceanic and reef-derived material. SIA have suggested that oceanic particulate organic matter (POM) flowing over reefs can be rapidly metabolized, with the subsequent release of remineralized inorganic nutrients, as well reef-derived POM, representing a significant resource for downstream communities. High oceanic concentrations of dissolved organic matter (DOM) relative to POM suggests DOM may be an even more significant resource, especially around low-POM reefs such as mid-ocean islands and atolls. However, DOM fluxes have rarely been quantified, perhaps due to the refractory nature of oceanic DOM and difficulties linking small concentration changes with spatial changes in both hydrodynamics and macro- and microbial communities. Our Lagrangian studies of DOM around Moorea, French Polynesia and Ishigaki Island, Japan suggest that DOM changes occurring over short spatial scales reflect a balance between uptake and release. SIA further suggest that the release of reef-derived DOM (i.e. enriched in 13C), perhaps relatively labile and from nitrogen fixing organisms (i.e. depleted in 15N), may promote nutrient recycling and supply to downstream communities. Linking SIA and local hydrodynamics offers a promising path towards elucidating the relative functional importance of oceanic and reef-level processes for reef communities.

Holobionts are species-specific associations between macro- and microorganisms. On coral reefs, the benthic coverage of coral and algal holobionts varies due to natural and anthropogenic forcings. Different benthic macroorganisms are predicted to have specific microbiomes. In contrast, local environmental factors are predicted to select for specific metabolic pathways in microbes. To reconcile these two predictions, we hypothesized that adaptation of microbiomes to local conditions is facilitated by the horizontal transfer of genes responsible for specific metabolic capabilities. To test this hypothesis, microbial metagenomes were sequenced from 22 coral reefs at 11 Line Islands in the central Pacific that together span a wide range of biogeochemical and anthropogenic influences. Consistent with our hypothesis, the percent cover of major benthic functional groups significantly correlated with particular microbial taxa. Reefs with higher coral cover had a coral microbiome with higher abundances of Alphaproteobacteria (such as Rhodobacterales and Sphingomonadales), whereas microbiomes of algae-dominated reefs had higher abundances of Gammaproteobacteria (such as Alteromonadales, Pseudomonadales, and Vibrionales), Betaproteobacteria, and Bacteriodetes. In contrast to taxa, geography was the strongest predictor of microbial community metabolism. Microbial communities on reefs with higher nutrient availability (e.g., equatorial upwelling zones) were enriched in genes involved in nutrient-related metabolisms (e.g., nitrate and nitrite ammonification, Ton/Tol transport, etc.). On reefs further from the equator, microbes had more genes encoding chlorophyll biosynthesis and photosystems I/II. These results support the hypothesis that core microbiomes are determined by holobiont macroorganisms, and that those core taxa adapt to local conditions by selecting for advantageous metabolic genes.

Benthic primary producers in tropical reef ecosystems can alter biogeochemical cycling and microbial processes in the surrounding seawater. In order to quantify these influences, we measured rates of photosynthesis, respiration, and dissolved organic carbon (DOC) exudate release by the dominant benthic primary producers (calcifying and non-calcifying macroalgae, turf-algae and corals) on reefs of Mo'orea French Polynesia. Subsequently, we examined planktonic and benthic microbial community response to these dissolved exudates by measuring bacterial growth rates and oxygen and DOC fluxes in dark and daylight incubation experiments. All benthic primary producers exuded significant quantities of DOC (roughly 10% of their daily fixed carbon) into the surrounding water over a diurnal cycle. The microbial community responses were dependent upon the source of the exudates and whether the inoculum of microbes included planktonic or planktonic plus benthic communities. The planktonic and benthic microbial communities in the unamended control treatments exhibited opposing influences on DO concentration where respiration dominated in treatments comprised solely of plankton and autotrophy dominated in treatments with benthic plus plankon microbial communities. Coral exudates (and associated inorganic nutrients) caused a shift towards a net autotrophic microbial metabolism by increasing the net production of oxygen by the benthic and decreasing the net consumption of oxygen by the planktonic microbial community. In contrast, the addition of algal exudates decreased the net primary production by the benthic communities and increased the net consumption of oxygen by the planktonic microbial community thereby resulting in a shift towards net heterotrophic community metabolism. When scaled up to the reef habitat, exudate-induced effects on microbial respiration did not outweigh the high oxygen production rates of benthic algae, such that reef areas dominated with benthic primary pro

Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of conditions where the detection of the desired signal using cross-spectral fails partially or entirely in the presence of a second uncorrelated signal. Not understanding when and how this effect occurs can lead to dramatic underreporting of the desired signal. Theoretical, simulated and experimental demonstrations of this effect as well as mitigating methods are presented.

Background/Aims: Chronic kidney disease (CKD) is a major health issue worldwide. The aim of this study was to explore factors associated with CKD progression in Australian nephrology practices. Methods: This was a retrospective study utilising an electronic medical record (EMR), Audit4 (Software for Specialists, Australia). The baseline visit was defined as the first entry into the EMR. The primary outcome was the rate of change in estimated glomerular filtration rate (eGFR). Results: 1,328 patients were included with a mean eGFR at baseline of 37.4 ± 0.7 ml/min/1.73 m2, a mean follow-up of 17.7 months and a mean annual rate of change in eGFR of –0.84 ± 0.26 ml/min/1.73 m2. Univariate analysis demonstrated that women, smokers, and patients prescribed erythropoiesis-stimulating agents (ESA) had a significantly more rapid decline in eGFR (p = 0.007, 0.033, and 0.003, respectively). On multivariate analysis: gender, age, prescription of ESA and phosphate binders, and baseline eGFR were significantly associated with CKD progression (p = 0.003, 0.004

http://archive.org/details/windstressndwind1094517996, NA, NA

Benthic primary producers in marine ecosystems may significantly alter biogeochemical cycling and microbial processes in their surrounding environment. To examine these interactions, we studied dissolved organic matter release by dominant benthic taxa and subsequent microbial remineralization in the lagoonal reefs of Moorea, French Polynesia. Rates of photosynthesis, respiration, and dissolved organic carbon (DOC) release were assessed for several common benthic reef organisms from the backreef habitat. We assessed microbial community response to dissolved exudates of each benthic producer by measuring bacterioplankton growth, respiration, and DOC drawdown in two-day dark dilution culture incubations. Experiments were conducted for six benthic producers: three species of macroalgae (each representing a different algal phylum: Turbinaria ornata - Ochrophyta; Amansia rhodantha - Rhodophyta; Halimeda opuntia - Chlorophyta), a mixed assemblage of turf algae, a species of crustose coralline algae (Hydrolithon reinboldii) and a dominant hermatypic coral (Porites lobata). Our results show that all five types of algae, but not the coral, exuded significant amounts of labile DOC into their surrounding environment. In general, primary producers with the highest rates of photosynthesis released the most DOC and yielded the greatest bacterioplankton growth; turf algae produced nearly twice as much DOC per unit surface area than the other benthic producers (14.0±2.8 μmol h -1 dm -2 ), stimulating rapid bacterioplankton growth (0.044±0.002 log10 cells h -1 ) and concomitant oxygen drawdown (0.16±0.05 μmol L -1 h -1 dm -2 ). Our results demonstrate that benthic reef algae can release a significant fraction of their photosynthetically-fixed carbon as DOC, these release rates vary by species, and this DOC is available to and consumed by reef associated microbes. These data provide compelling evidence that benthic primary producers differentially influence reef microbial dynamics and

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in The ISME Journal 5 (2011): 1374–1387, doi:10.1038/ismej.2011.12., Coral reefs are highly productive ecosystems bathed in unproductive, low-nutrient oceanic waters, where microbially-dominated food webs are supported largely by bacterioplankton recycling of dissolved compounds. Despite evidence that benthic reef organisms efficiently scavenge particulate organic matter and inorganic nutrients from advected oceanic waters, our understanding of the role of bacterioplankton and dissolved organic matter in the interaction between reefs and the surrounding ocean remains limited. Here we present the results of a four-year study conducted in a well-characterized coral reef ecosystem (Paopao Bay, Moorea, French Polynesia) where changes in bacterioplankton abundance and dissolved organic carbon (DOC) concentrations were quantified and bacterial community structure variation was examined along spatial gradients of the reef:ocean interface. Our results illustrate that the reef is consistently depleted in concentrations of both DOC and bacterioplankton relative to offshore waters (averaging 79 µmol L-1 DOC and 5.5 X 108 cells L-1 offshore and 68 µmol L-1 DOC and 3.1 X 108 cells L-1 over the reef, respectively) across a four year time period. In addition, using a suite of culture-independent measures of bacterial community structure, we found consistent differentiation of reef bacterioplankton communities from those offshore or in a nearby embayment across all taxonomic levels. Reef habitats were enriched in Gamma-, Delta-, and Beta-proteobacteria, Bacteriodetes, Actinobacteria and Firmicutes. Specific bacterial phylotypes, including members of the SAR11, SAR116, Flavobacteria, and Synechococcus clades, exhibited clear gradients in relative abundance among nearshore habitats. Our observations indicate that this reef system removes oceanic DOC and exerts selective pressures on bacterioplankton community structure on timescales approximating reef water residence times, observations which are notable both because fringing reefs do not exhibit long, This project was supported by the US National Science Foundation Moorea Coral Reef Long Term Ecological Research project (NSF OCE-0417412) through minigrants to CAC and NSF OCE-0927411 to CAC as well as the MIRADA-LTERs program (NSF DEB-0717390 to LAZ).

Objectives : Circulating low molecular weight (<10 kDa) fluorophores (LMW-F) measured by non-specific fluorescence spectroscopy may detect small advanced glycation end-products (AGEs) not recognized by other assays. This longitudinal study assessed correlates of LMW-F and predictive power of LMW-F levels for vascular health in Type 1 diabetes (T1DM) patients. Methods : Fasting patients with T1DM (n=37) were studied twice at intervals of 12-60 months (mean±SD, 33±15 months). LMW-F levels were also measured once in 112 healthy control subjects. Results : Relative to controls, LMW-F levels were higher in diabetic subjects at initial and final time points (mean±SD), 5.4±1.9 AU/ml and 4.5±1.8 AU/ml respectively vs. 3.8±2.1 AU/ml p=0.0001 and p=0.06). Baseline LMW-F levels predicted subsequent hs-CRP and oxLDL/LDL values. LMW-F levels decreased significantly over time in diabetes (5.4±1.9 vs. 4.5±1.8 AU/ml p=0.02). Rises in LMW-F levels in individual diabetic subjects correlated significantly with worsening renal function (BUN), glycemia (HbA1c) and with vascular dysfunction (systemic vascular resistance). Conclusions : LMW-F levels predict levels of inflammation and oxidation in T1DM. Changes in LMW-F levels in T1DM reflect variations in glycemia and renal function. Biochemical characterization of LMW-F would facilitate understanding of the potential utility of LMW-F as a therapeutic target.

A high-resolution, multi-level, primitive equation ocean model is used to examine the response of the coastal region from 22.5~ to 35~ of the Chile Current System to both equatorward and climatological wind forcing. The results from both types of forcing show that an equatorward surface current, a poleward undercurrent, upwelling, meanders, filaments and eddies develop in response to the predominant equatorward wind forcing. When climatological wind forcing is used, an offshore branch of the equatorward Surface current is also generated. These features are consistent with available observations of the Chile Current System. The model results support the hypothesis that wind forcing is an important mechanism for generating currents, eddies and filaments in the Chile eastern boundary current system and in other eastern boundary current regions which have predominantly equatorward wind forcing.

There are some indications that in large measure the density anomaly field of the California Current system (CCS) follows temperature, salinity playing a significantly lesser role. These indications have been used as justification for not taking as extensive salinity as temperature observations in the CCS, as well as for using fixed or prescribed salinity fields in density calculations in dynamic models of the CCS. An extensive data base of temperature-salinity observations from the CCS is used to show that there are noticeable differences between the dynamic height field calculated with and without the inclusion of salinity variations. Hence the distribution of salinity is important in defining the large-scale circulation of the CCS. In particular, owing to the combined effect of temperature and salinity on density, the dynamic height fields show a significant equatorward component along the coast of California and a strong offshore component adjacent to Baja California. Based on these observations, it is concluded that descriptively and dynamically, both temperature and salinity are essential to accurately characterize the large-scale structure of the CCS.

A high-resolution, multi-level, primitive equation ocean model is used to examine the response to the particular conditions of anticyclonic (negative) wind stress curl and equatorward (upwelling favorable) winds along the eastern ocean boundary of the northwest coast of the Iberian Peninsula in the vicinity of the highly productive rias. A band of steady equatorward winds, which are uniform alongshore but contain zonal variability (i.e. anticyclone wind stress curl), results in an equatorward coastal surface current nearshore and a poleward surface current offshore. In time, the currents become unstable and lead to the development of anticyclonic warm core eddies. In addition, cold core filament formation occurs in areas where the anticylclones advect the upwelled coastal water offshore. The results from the experiments support the hypothesis that wind forcing, particularly the combination of anticyclonic (negative) wind stress curl and equatorward (upwelling favorable) winds, is an important mechanism for generating opposing alongshore surface currents, anticyclonic eddies and filaments off the northwest coast of the Iberian Peninsula. In a sensitivity study, the results from three numerical experiments are examined to understand, in a limited way, the dependence of the generation of the surface currents on the boundary conditions (Free slip and no slip), the use of wind band forcing and the imposed wind stress curl distribution. Results show that, regardless of whether free-slip or no-slip boundary conditions or wind band forcing are used, opposing alongshore surface currents are generated. Because such current do not develop when there is no wind stress curl, the opposing currents are generated by the anticyclonic wind stress curl.

A process-oriented study of time-dependent wind forcing is conducted using a ten-layer (B)-plane, positive ocean model to provide insight into mesoscale eddy generation and duration off the west coast of Portugal from 1987 to 1988. The wind forcing used was derived from synoptic surface pressure analyses off Lisbon, Portugal. Results obtained show that eddies generated during the coastal upwelling season (generally occurring during the spring and summer) decay during the winter. Only cyclonic eddies form during the 1987 and 1988 upwelling seasons. The eddies are generated through a combination of barotropic and baroclinic instability mechanisms. Since the wind forcing of the five-month long 1987 upwelling season, eddy characteristics appear to be more influenced by the characteristics (e.g., intensity, duration and frequency of occurrence) of the wind forcing than by the total length of the upwelling season. This study affirms the importance of wind stress forcing to the overall surface circulation and eddy generation in the coastal regime off the west coast of Portugal.

Given the disappointing results of U. S. interventions in Iraq and Afghanistan to reach strategic goals through influence on those countries' military elements of national power, it is logical to conclude that it is a mistake to impose western military doctrine in places which have developed free of western context. However, Great Britain met its strategic goals throughout the Indian subcontinent in the 17th, 18th, and 19th centuries by cultivating a privatized and indigenous military force there by way of the Honorable East India Company. In doing so, the Company achieved lasting effects in India which offer insight into how modern military advisors could improve efforts at security cooperation with foreign allies.

Historical surface marine observations are summarized by 1-degree square area and long term month to describe the seasonal distribution of wind stress over the California Current. Off the coasts of southern California and Baja California, an alongshore equatorward component is present throughout the year. The distributions north of Cape Mendocino are characterized by marked changes in direction and magnitude between summer and winter. The predominant wind stress maximum shifts northward coherently from off Point Conception in March to south of Cape Blanco in September, and extends approximately 500 km in the offshore direction and 1000 km in the alongshore direction. Maximum values of surface wind stress occur during July near Cape Mendocino. The wind stress curl is positive near the coast and negative in the region offshore.

There are some indications that in large measure the density anomaly field of the California Current System (CCS) follows temperature, salinity playing a significantly lesser role. These indications have been used as justification for ignoring salinity variations in dynamic models. An extensive data base of simultaneous temperature-salinity observations taken in the CCS is used to calculate and assess the saline contribution to specific volume anomaly, dynamic height, and density variance. The results show that the distribution of salinity can be important in defining the large scale circulation of the CCS, and that the local variability can be quite significant.

There are some indications that in large measure the density anomaly field of the California Current System (CCS) follows temperature, salinity playing a significantly lesser role. These indications have been used as justification for ignoring salinity variations in dynamic models. An extensive data base of simultaneous temperature-salinity observations taken in the CCS is used to calculate and assess the saline contribution to specific volume anomaly, dynamic height, and density variance. The results show that the distribution of salinity can be important in defining the large scale circulation of the CCS, and that the local variability can be quite significant., Chief of Naval Research, http://archive.org/details/salineimpactonca1094527247, OM&N, Direct funding, Lieutenant Commander, United States Navy, Approved for public release; distribution is unlimited.

Funded by Naval Postgraduate School, A process-oriented study of time-dependent wind forcing is conducted using a ten-layer (B)-plane, positive ocean model to provide insight into mesoscale eddy generation and duration off the west coast of Portugal from 1987 to 1988. The wind forcing used was derived from synoptic surface pressure analyses off Lisbon, Portugal. Results obtained show that eddies generated during the coastal upwelling season (generally occurring during the spring and summer) decay during the winter. Only cyclonic eddies form during the 1987 and 1988 upwelling seasons. The eddies are generated through a combination of barotropic and baroclinic instability mechanisms. Since the wind forcing of the five-month long 1987 upwelling season, eddy characteristics appear to be more influenced by the characteristics (e.g., intensity, duration and frequency of occurrence) of the wind forcing than by the total length of the upwelling season. This study affirms the importance of wind stress forcing to the overall surface circulation and eddy generation in the coastal regime off the west coast of Portugal., Office of Naval Research; O & MN, Direct funding, The work reported herein was prepared for the Office of Naval Research and funded by Naval Postgraduate School., http://archive.org/details/anumericalstudyo1094528410, The work reported herein was prepared for the Office of Naval Research and funded by Naval Postgraduate School., Lieutenant, United States Navy, Approved for public release; distribution is unlimited.