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Climate effects on hydrology impart high variability to water-quality properties, including nutrient loadings, concentrations, and phytoplankton biomass as chlorophyll-a (chl-a), in estuarine and coastal ecosystems. Resolving long-term trends of these properties requires that we distinguish climate effects from secular changes reflecting anthropogenic eutrophication. Here, we test the hypothesis that strong climatic contrasts leading to irregular dry and wet periods contribute significantly to interannual variability of mean annual values of water-quality properties using in situ data for Chesapeake Bay. Climate effects are quantified using annual freshwater discharge from the Susquehanna River together with a synoptic climatology for the Chesapeake Bay region based on predominant sea-level pressure patterns. Time series of water-quality properties are analyzed using historical (1945–1983) and recent (1984–2012) data for the bay adjusted for climate effects on hydrology. Contemporary monitoring by the Chesapeake Bay Program (CBP) provides data for a period since mid-1984 that is significantly impacted by anthropogenic eutrophication, while historical data back to 1945 serve as historical context for a period prior to severe impairments. The generalized additive model (GAM) and the generalized additive mixed model (GAMM) are developed for nutrient loadings and concentrations (total nitrogen—TN, nitrate + nitrate—NO₂ + NO₃) at the Susquehanna River and water-quality properties in the bay proper, including dissolved nutrients (NO₂ + NO₃, orthophosphate—PO₄), chl-a, diffuse light attenuation coefficient (K D (PAR)), and chl-a/TN. Each statistical model consists of a sum of nonlinear functions to generate flow-adjusted time series and compute long-term trends accounting for climate effects on hydrology. We present results identifying successive periods of (1) eutrophication ca. 1945–1980 characterized by approximately doubled TN and NO₂ + NO₃ loadings, leading to increased chl-a and associated ecosystem impairments, and (2) modest decreases of TN and NO₂ + NO₃ loadings from 1981 to 2012, signaling a partial reversal of nutrient over-enrichment. Comparison of our findings with long-term trends of water-quality properties for a variety of estuarine and coastal ecosystems around the world reveals that trends for Chesapeake Bay are weaker than for other systems subject to strenuous management efforts, suggesting that more aggressive actions than those undertaken to date will be required to counter anthropogenic eutrophication of this valuable resource.

Background/Objectives: Several studies have linked dietary patterns to insulin sensitivity and systemic inflammation, which affect risk of multiple chronic diseases. The purpose of this study was to investigate the dietary patterns of a cohort of older adults, and to examine relationships of dietary patterns with markers of insulin sensitivity and systemic inflammation. Subjects/Methods: The Health, Aging and Body Composition (Health ABC) Study is a prospective cohort study of 3075 older adults. In Health ABC, multiple indicators of glucose metabolism and systemic inflammation were assessed. Food intake was estimated with a modified Block food frequency questionnaire. In this study, dietary patterns of 1751 participants with complete data were derived by cluster analysis. Results: Six clusters were identified, including a ‘healthy foods’ cluster, characterized by higher intake of low-fat dairy products, fruit, whole grains, poultry, fish and vegetables. In the main analysis, the ‘healthy foods’ cluster had significantly lower fasting insulin and homeostasis model assessment of insulin resistance values than the ‘breakfast cereal’ and ‘high-fat dairy products’ clusters, and lower fasting glucose than the ‘high-fat dairy products’ cluster ( P⩽ 0.05). No differences were found in 2-h glucose. With respect to inflammation, the ‘healthy foods’ cluster had lower interleukin-6 than the ‘sweets and desserts’ and ‘high-fat dairy products’ clusters, and no differences were seen in C-reactive protein or tumor necrosis factor-α. Conclusions: A dietary pattern high in low-fat dairy products, fruit, whole grains, poultry, fish and vegetables may be associated with greater insulin sensitivity and lower systemic inflammation in older adults.

The Cordillera Huayhuash is a north-south-oriented range along the drainage divide of the northern Peruvian Andes. The range has high topography with peaks in excess of 5500 m and the second-highest peak in Peru, Nevados Yerupaja (6617 m). Bedrock is dominated by folded Mesozoic miogeoclinal rocks unconformably overlain by mid-Tertiary volcanics intruded by Late Tertiary granitic rocks and silicic dikes. Zircon fission track (ZFT) and (U-Th)/He (ZHe) dating of zircons along a west-east transect elucidates the thermal evolution of exhumed and uplifted rocks. The stability of fission tracks in zircons is a function of single-grain radiation damage. In samples with grain-to-grain variability in radiation damage, resetting results in variable resetting and multiple age populations. Low retentive zircons (LRZs), which have a partly disordered crystalline structure, have significant radiation damage and a low temperature of annealing (ca. 180°-200°C). High retentive zircons (HRZs), which are nearly crystalline, fully anneal at temperatures in excess of ca. 280°-300°C. Partly reset samples are those where LRZs are reset and HRZs are not reset, and therefore the cooling age is not concordant, but the young population of grain ages records the youngest thermal event. Full resetting of both LRZs and HRZs results in cooling ages that are concordant or nearly so. Lower Cretaceous quartzites show ZFT ages with a wide range of cooling ages, but most have LRZ reset ages at ca. 27 and 63 Ma. The ZFT ages from three quartzites and two granites from the core of the range yielded a single mean reset age of 11.4±1 Ma. The ZHe ages from four samples in these rocks ranged from 10 to 7 Ma, with older ages away from the high topography. Together, the ZFT and ZHe cooling ages near the core of the range indicate moderate to rapid postintrusive cooling in the Miocene and a high Miocene geothermal gradient (ca. 40°-50°C/km). This widespread cooling age represents a falling geotherm, not a period of significant exhumation. Estimations of the thickness of preexhumation cover rock suggest that nearly 5 km of unroofing has occurred since the eruption of the Puscanturpa Formation (Huayllay Formation) at ca. 6.2 Ma. Exhumation was driven by valley incision initiated by uplift of this part of the Andes between 5 and 6 Ma. The high topography may have been formed by isostatic response to canyon incision. Therefore, the thermochronologic record of uplift and canyon incision is not yet apparent in the low-temperature thermochronology (for zircons) of these rocks.

In coastal ecosystems with long flushing times (weeks to months) relative to phytoplankton growth rates (hours to days), chlorophyll a (chl-a) integrates nutrient loading, making it a pivotal indicator with broad implications for ecosystem function and water-quality management. However, numerical chl-a criteria that capture the linkage between chl-a and ecosystem impairments associated with eutrophication (e.g., hypoxia, water clarity and loss of submerged aquatic vegetation, toxic algal blooms) have seldom been developed despite the vulnerability of these ecosystems to anthropogenic nutrient loading. Increases in fertilizer use, animal wastes, and population growth in the Chesapeake Bay watershed since World War II have led to increases in nutrient loading and chl-a. We describe the development of numerical chl-a criteria based on long-term research and monitoring of the bay. Baseline chl-a concentrations were derived using statistical models for historical data from the 1960s and 1970s, including terms to account for the effects of climate variability. This approach produced numerical chl-a criteria presented as geometric means and 90th percentile thresholds to be used as goals and compliance limits, respectively. We present scientific bases for these criteria that consider specific ecosystem impairments linked to increased chl-a, including low dissolved oxygen (DO), reduced water clarity, and toxic algal blooms. These multiple lines of evidence support numerical chl-a criteria consisting of seasonal mean chl-a across salinity zones ranging from 1.4 to 15 mg m⁻³ as restoration goals and corresponding thresholds ranging from 4.3 to 45 mg m⁻³ as compliance limits. Attainment of these goals and limits for chl-a is a precondition for attaining desired levels of DO, water clarity, and toxic phytoplankton prior to rapid human expansion in the watershed and associated increases of nutrient loading.

Two hypotheses have been offered to account for the transport and accretion history of the Yakutat terrane in southern Alaska. To investigate these two options, we deconvolved fission-track (FT) and U/Pb ages of detrital zircons from stratigraphically coordinated samples collected in the northern Robinson Mountains into component populations. The strata of the Yakutat terrane include the Middle Eocene Kulthieth Formation, the Lower Oligocene to Lower Miocene Poul Creek Formation, and the Miocene-Pleistocene Yakataga Formation. The Kulthieth and Poul Creek formations record erosion of a simple, uniform, long-lived, nonvolcanic source terrain that crystallized from ∼50 to 220 Ma and cooled from ∼40 to 110 Ma. Miocene cooling episodes recorded in the source to the Kulthieth and Poul Creek formations are likely associated with plutons in the northern Coast Plutonic Complex and the Kuiu-Etoilin belt. The Upper Miocene to Pleistocene Yakataga Formation records erosion of rocks that crystallized from ∼50 to 53 Ma and cooled below the zircon FT closure at ∼70-20 Ma. Upper Miocene strata are likely derived from erosion of the Chugach-Prince William terranes and the superimposed Sanak-Baranof plutonic belt. The uniform provenance of the Kulthieth and Poul Creek formations, the overall FT grain age distribution, and the distinct lack of volcanic zircons favor a northern position of the Yakutat terrane since the Eocene. However, a far-traveled southern option for the basement rocks cannot be ruled out, but it is unlikely that the Eocene and younger cover strata were deposited far to the south.

Background:Daily stressors are associated with cognitive decline and increased risk of heart disease, depression, and other debilitating chronic illnesses in midlife adults. Daily stressors tend to occur at home or at work and are more frequent in urban versus rural settings. Conversely, spending time in natural environments such as parks or forests, or even viewing nature-themed images in a lab setting, is associated with lower levels of perceived stress and is hypothesized to be a strong stress “buffer,” reducing perceived stress even after leaving the natural setting. However, many studies of daily stress have not captured environmental contexts and relied on end-of-day recall instead of in-the-moment data capture. With new technology, these limitations can be addressed to enhance knowledge of the daily stress experience.Objective:We propose to use our novel custom-built Stress Reports in Variable Environments (STRIVE) ecological momentary assessment mobile phone app to measure the experience of daily stress of midlife adults in free-living conditions. Using our app to capture data in real time will allow us to determine (1) where and when daily stress occurs for midlife adults, (2) whether midlife adults’ daily stressors are linked to certain elements of the built and natural environment, and (3) how ecological momentary assessment measurement of daily stress is similar to and different from a modified version of the popular Daily Inventory of Stressful Events measurement tool that captures end-of-day stress reports (used in the Midlife in the United States [MIDUS] survey).Methods:We will enroll a total of 150 midlife adults living in greater Indianapolis, Indiana, in this study on a rolling basis for 3-week periods. As those in underrepresented minority groups and low-income areas have previously been found to experience greater levels of stress, we will use stratified sampling to ensure that half of our study sample is composed of underrepresented minorities (eg, Black, American Indian, Hispanic, or Native Pacific Islanders) and approximately one-third of our sample falls within low-, middle-, and high-income brackets.Results:This project is funded by the National Institute on Aging from December 2022 to November 2024. Participant enrollment began in August 2023 and is expected to finish in July 2024. Data will be spatiotemporally analyzed to determine where and when stress occurs for midlife adults. Pictures of stressful environments will be qualitatively analyzed to determine the common elements of stressful environments. Data collected by the STRIVE app will be compared with retrospective Daily Inventory of Stressful Events data.Conclusions:Completing this study will expand our understanding of midlife adults’ experience of stress in free-living conditions and pave the way for data-driven individual and community-based intervention designs to promote health and well-being in midlife adults.International Registered Report Identifier (IRRID):DERR1-10.2196/51845

The post-translational transport of cytoplasmically synthesized precursor proteins into chloroplasts requires proteins in the envelope membranes. To identify some of these proteins, label transfer cross-linking was performed using precursor to the small subunit of ribulose-1,5-bisphosphate carboxylase (prSSU) that was blocked at an early stage of the transport process. Two envelope proteins were identified: an 86-kD protein and a 75-kD protein, both present in the outer membrane. Labeling of both proteins required prSSU and could not be accomplished with SSU lacking a transit peptide. Labeling of the 75-kD protein occurred only when low levels of ATP were present, whereas labeling of the 86-kD protein occurred in the absence of exogenous ATR Although both labeled proteins were identified as proteins of the outer envelope membrane, the labeled form of the 75-kD protein could only be detected in fractions containing mixed envelope membranes. Based on these observations, we propose that prSSU first binds in an ATP-independent fashion to the 86-kD protein. The energy-requiring step is association with the 75-kD protein and assembly of a translocation contact site between the inner and outer membrane of the chloroplastic envelops.

To extend our knowledge of genes expressed during early embryogenesis, the differential display technique was used to identify and isolate mRNA sequences that accumulate preferentially in young Brassica napus embryos. One of these genes encodes a new member of the MADS domain family of regulatory proteins; it has been designated AGL15 (for AGAMOUS-like). AGL15 shows a novel pattern of expression that is distinct from those of previously characterized family members. RNA gel blot analyses and in situ hybridization techniques were used to demonstrate that AGL15 mRNA accumulated primarily in the embryo and was present in all embryonic tissues, beginning at least as early as late globular stage in B. napus. Genomic and cDNA clones corresponding to two AGL15 genes from B. napus and the homologous single copy gene from Arabidopsis, which is located on chromosome 5, were isolated and analyzed. Antibodies prepared against overexpressed Brassica AGL15 lacking the conserved MADS domain were used to probe immunoblots, and AGL15-related proteins were found in embryos of a variety of angiosperms, including plants as distantly related as maize. Based on these data, we suggest that AGL15 is likely to be an important component of the regulatory circuitry directing seed-specific processes in the developing embryo

An analysis of historical and recent data on chlorophyll a for Chesapeake Bay reveals that a significant increase of phytoplankton biomass has occurred during the last 40 to 50 yr. Concentrations of chlorophyll a in the surface mixing layer have increased 5- to 10-fold in the seaward regions of the estuary and 1.5- to 2-fold elsewhere, paralleling published estimates of increased loading of N and P to the estuary since World War II. The characteristic high variability of freshwater flow that occurs on seasonal to interannual time scales, however, drives fluctuations of chlorophyll a that are superimposed on this apparent upward trend, potentially obscuring the effects of overenrichment on chlorophyll a concentrations in nutrient-limited regions of the Bay. To resolve a time trend of chlorophyll from this variability, we developed regional models of mean, monthly chlorophyll a using autoregressive moving average (ARMA) procedures. The models were developed with water quality data from monitoring cruises of the Chesapeake Bay Program spanning 1984 to 1992. The approach was to: (1) determine the relationship of prominent variables, including freshwater flow, salinity, temperature, region, and time of year, to chlorophyll a for the 'modern' Bay; (2) predict chlorophyll a for the 'historical' Bay based on these models and actual, observed variables for periods from 1950 to 1984 for which chlorophyll a data were available; (3) compare chlorophyll a predicted from modern relationships, to those observed in the past, using the residuals to identify deviations below or above expected concentrations that would suggest an effect on chlorophyll a unrelated to flow variability. The results show that: (1) observed and predicted chlorophyll a concentrations matched reasonably well for the years that were used to develop the models, with some exceptions when the models failed to capture extremely high concentrations of chlorophyll a during blooms; (2) chlorophyll a concentrations in the 1950s, 1960s, and 1970s were predominantly lower than predicted by the models, particularly in the mesohaline and polyhaline regions of the estuary that are most susceptible to nutrient limitation; (3) chlorophyll a concentrations were lower in the 1960s than in the 1970s, probably as the result of low flow and a concomitant reduction of nutrient loading in the 'dry' 1960s as compared to the 'wet' 1970s; (4) interannual variability was high for both observed and predicted chlorophyll a concentrations in the 1970s, and this variability was most strongly expressed in the mesohaline to polyhaline Bay, reflecting the spatial and temporal heterogeneity of phytoplankton that prevailed in that period. These findings support the hypothesis that a significant increase of chlorophyll a has occurred in the lower Bay that cannot be accounted for by variability of freshwater flow and attendant properties.

AGL15 (AGAMOUS-like 15), a member of the MADS-domain family of regulatory factors, accumulates preferentially in the organs and tissues derived from double fertilization in flowering plants (i.e. the embryo, suspensor, and endosperm). The developmental role of AGL15 is still undefined. If it is involved in embryogenesis rather than some other aspect of seed biology, then ALG15 protein should accumulate whenever development proceeds in the embryonic mode, regardless of the origin of those embryos or their developmental context. To test this, we used AGL15-specific antibodies to analyze apomictic embryogenesis in dandelion (Taraxacum officinale), microspore embryogenesis in oilseed rape (Brassica napus), and somatic embryogenesis in alfalfa (Medicago sativa). In every case, AGL15 accumulated to relatively high levels in the nuclei of the embryos. AGL15 also accumulated in cotyledon-like organs produced by the xtc2 (extra cotyledon2) mutant of Arabidopsis and during precocious germination in oilseed rape. Furthermore, the subcellular localization of AGL15 appeared to be developmentally regulated in all embryogenic situations. AGL15 was initially present in the cytoplasm of cells and became nuclear localized before or soon after embryogenic cell divisions began. These results support the hypothesis that AGL15 participates in the regulation of programs active during the early stages of embryo development.