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Objective: To assess acceptability and feasibility of rapid at-home COVID-19 testing and reporting of test results among individuals seeking care at community health centers (CHCs) and their household members. Methods: Participants were recruited from 2 Community Health Centers during a clinic visit or a community event. Over-the-counter COVID-19 tests were distributed to participants for self-testing and to offer testing to household members. Separate surveys were administered to collect baseline information on the study participant and to collect test results on the study participant and household members. We calculated the proportion of individuals who agreed to complete COVID home testing, those who reported test results, and the test positivity. For household members, we calculated the proportion who completed and reported results and the positivity rate. We assessed reasons for undergoing COVID-19 testing and the action taken by participants who reported positive tests. Results: A total of 2189 individuals were approached by CHC staff for participation and 1013 (46.3%) agreed to participate. Among the 959 participants with complete sociodemographic data, 88% were Hispanic and 82.6% were female. The proportion providing test results was 36.2% and the test positivity was 4.2%. Among the 1927 test reports, 35.3% for the index participant and 64.4% were for household members. The largest proportion of test results were for index participants (35.3%) and the second largest was for the participant's children (32.1%), followed by parents (16.9%), and spouse/partner (13.2%). The 2 most common reasons for testing were symptoms (29%) and attending family gatherings (26%). Among test-positive individuals (n = 80), most (83.3%) noted that they isolated but only 16.3% called their provider and 1.3% visited a clinic. Conclusion: Our results show interest in at-home COVID-19 testing of multiple household members, as we headed into the endemic phase of the pandemic. However, reporting of test results was modest and among test-positive individuals, reporting results to a provider was very low. These results underscore the challenges with reporting and following guidelines among people undergoing home testing for COVID-19, which may have implications for future pandemics. [ABSTRACT FROM AUTHOR]

The pelagic contribution to total gross primary production (GPP) is often used to evaluate the assemblages of primary producers in shallow estuarine and coastal ecosystems that shift between benthic‐dominated and pelagic‐dominated status as a response to nutrient loading change. This study investigated the spatial and temporal variability of the pelagic contribution to ecosystem GPP for the years 2003–2015 in shallow areas of the York River. The monthly average values of ecosystem GPP and pelagic GPP were estimated by using 15‐min observational data of dissolved oxygen and chlorophyll a, respectively. A larger pelagic contribution, generally, corresponded to a higher pelagic GPP, while pelagic GPP showed significant positive correlations to riverine discharge and total nitrogen loading at mesohaline and polyhaline stations. The interannual variability in benthic GPP (ecosystem GPP – pelagic GPP), however, exhibited a non‐monotonic relationship to the increase in pelagic GPP. A conceptual model with four ecosystem stages in response to nutrient loading changes is proposed based on changes in the relationship between benthic GPP and pelagic GPP, and that between pelagic contribution and pelagic GPP. The model can explain the different responses of an ecosystem to nutrient loading observed in various estuaries and can be used to evaluate the status of an ecosystem undergoing the eutrophication/oligotrophication process. The stages of York River ecosystems during the study period were quantitatively examined. Results suggest that benthic GPP shows negative correlations to pelagic GPP in the downstream York River over most months of the year, indicating a gradual degradation of the benthic community. [ABSTRACT FROM AUTHOR]

Objectives. To determine age-associated changes in cardiorespiratory fitness (CRF) among firefighters. Methods. Male firefighters (n = 1169) underwent annual evaluations from 2005 to 2015 in San Diego, California. We assessed CRF, the ability to deliver and use oxygen, during a maximal graded exercise test and recorded it in metabolic equivalents (METs; 1 MET = 3.5 ml/kg/min). We investigated differences in baseline CRF among 10-year age groups and patterns of change over follow-up using cross-sectional and longitudinal analyses, respectively. Results. Both analyses support an inverse relationship between CRF and age. Mean baseline CRF decreased from 15.7 61.7 to 11.7 61.9 METs in the younger than 30 years and 50 years and older age groups, respectively. There was no interaction between body fat and age in predicting CRF (Page x body fat = .09). Longitudinally, there was a nonlinear decrease in CRF, which differed across age groups: the youngest age group demonstrated the greatest decrease in CRF. Conclusions. Results support a negative, nonlinear association between age and CRF without modification by body fatness. Public Health Implications. Fire departments should recognize the health and safety risks of declining CRF and institutionalize programs to promote firefighter fitness. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the changes of hydrodynamics in estuaries with respect to magnitudes of sea-level rise is important to understanding the changes of biogeochemical processes that are coupled tightly with the physical processes. Based on the 21st century sea-level rise scenarios projected by the U.S. Climate Change Science Program (), the Chesapeake Bay was chosen as a prototype to study the responses of the estuary to potential future sea-level rise. The numerical model results show that the average salt content, salt intrusion length, and stratification will increase as sea level rises. The changes of these parameters have obvious seasonal and inter-annual variations. Both the salt content and stratification show more increase in spring (following the high-flow periods) and wet years than in autumn (following the low-flow periods) and dry years. The salt intrusion length has larger increase and greater standard deviation in autumn than in spring. The transport time scales are used to illustrate the variations of transport processes as sea level rises, and results indicate that (1) the exchange flow would be strengthened but the downstream transport of fresh water would be slower; (2) the residence time of the Bay would increase due to the increased volume and change of circulation; (3) the vertical transport time (reference to water surface) has more pronounced increase and the volume of water mass with different age groups increases with different rates. As a result, the retention time of dissolved substances in the Bay would increase. Although the increased tidal currents would strengthen the vertical mixing, the increased stratification would weaken the vertical exchange. The increase of vertical transport time is due to the impact of stratification changes, which overwhelms the impact of tidal changes. As the bottom dissolved oxygen (DO) supply is predominated by the vertical exchanges in the Chesapeake Bay, the increased upstream transport time has a weak impact on hypoxia conditions in the middle and upper portions of the Bay. The weakened vertical exchange would result in less DO supply from the surface to the bottom layer. [Copyright &y& Elsevier]

The effectiveness of simulating surge inundation using the Eulerian-Lagrangian circulation (ELCIRC) model over multi-scale unstructured grids was examined in this study. The large domain model grid encompasses the western North Atlantic Ocean, the Gulf of Mexico, and the Caribbean Sea to appropriately account for remote and resonance effects during hurricane events and simplify the specification of the open boundary condition. The U.S. East and Gulf Coasts were divided into 12 overlapping basins with fine-resolution (up to 30 × 30 m) grids to model overland surge flooding. These overlapping basins have different fine-resolution grids near the coastal region, but have an identical coarse-resolution grid in the offshore region within the large model domain. Thus, the storm surge prediction can be conducted without reducing computation efficiency by executing multiple model runs with local fine-resolution grids where potential hurricane landfalls may occur. The capability of the multi-scale approach was examined by simulating storm surge caused by Hurricanes Andrew (1992) and Isabel (2003) along the South Florida coast and in the Chesapeake Bay. Comparisons between simulated and observed results suggest that multi-scale models proficiently simulated storm surges in the Biscayne Bay and the Chesapeake Bay during two hurricanes. A series of sensitivity tests demonstrated that the simulation of surge flooding was improved when LiDAR topographic data and special bottom drag coefficient values for mangrove forests were employed. The tests also showed that appropriate representation of linear hydrologic features is important for computing surge inundation in an urban area. [ABSTRACT FROM AUTHOR]

Abstract: Wind plays an important role in regulating mixing/stratification, estuarine circulation, and transport timescale in estuaries. A three-dimensional model was used to investigate the effect of wind on transport time by using the concept of water age (WA) in the tidal Rappahannock River, a western tributary of the Chesapeake Bay, USA. The model was calibrated for water level, current, and salinity. A series of experiments regarding the effects of wind on WA was conducted under various dynamic conditions. The effect of wind on transport timescale depends strongly on the competition between the wind and buoyancy forcings, and on the pre-status of the circulation. A down-estuary wind generally decreases WA along the estuary. An up-estuary wind increases WA substantially because it changes the vertical mixing and estuarine circulation more significantly. When the buoyancy forcing increases, the up-estuary wind effect decreases whereas the down-estuary wind effect increases. A 2-day period wind pulse with a maximum speed of 15ms−1 can alter WA for 3days; but the wind influence on WA lasts up to 40days in the simulation. Both local and non-local wind forcings alter WA distribution. The local wind enhances vertical mixing and changes the gravitational circulation in the downstream portion of the estuary whereas it enhances transport in the freshwater portion of the estuary. Consequently, the local wind has a significant impact on WA distribution. In contrast, the non-local wind does not change the gravitational circulation significantly by imposing setup (setdown) of water level at the open boundary, resulting in a lesser impact on WA distribution. [Copyright &y& Elsevier]

OBJECTIVE -- C-reactive protein (CRP) is an inflammatory marker that contributes to the prediction of cardiovascular disease. We investigated the influences of CRP polymorphisms on baseline CRP levels and fenofibrate-induced CRP changes in subjects with the metabolic syndrome. RESEARCH DESIGN AND METHODS -- We examined the association of CRP single nucleotide polymorphisms (SNPs) (m772A>G, m301G>A >T, i178T>A, 3u1273C>T, and 3u2131C>T) with baseline plasma CRP levels among 1,123 white U.S. participants in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) Study and the modulating effect of these SNPs on CRP response to a 3-week fenofibrate treatment among 290 participants with the metabolic syndrome. RESULTS -- There were strong associations of m301G>A>T (rs3091244; P = 0.003), i178T>A (rs1417938; P = 0.001), 3u1273C>T (rs1130864; P = 0.001), and 3u2131C>T (rs1205; P < 0.001) with baseline CRP levels. Moreover, among subjects with the metabolic syndrome, fenofibrate induced the greatest reduction in CRP levels for TT subjects of the i178T>A compared with TA and AA subjects (-30 for TT, -19 for TA, and -11% for AA; P = 0.004). Similarly, for the m301G>A>T, major allele carriers displayed maximal reduction of CRP over noncarriers (-20 for GG, -15 for GA and GT, and -0.3% for TA and AA; P = 0.020). CONCLUSIONS -- Our results demonstrate that common genetic variants within the CRP gene affect baseline CRP levels and further modulate CRP response in subjects with the metabolic syndrome treated with fenofibrate. This knowledge could contribute to a better prediction of therapeutic success. [ABSTRACT FROM AUTHOR]

Abstract: Hurricane Isabel made landfall near Drum Inlet, North Carolina on September 18, 2003 (UTC 17:00). Although it was classified as only a Category 2 storm (Saffir–Simpson scale), Hurricane Isabel had a significant impact on the Chesapeake Bay with a 1.5–2.0m storm surge (above mean sea level), and was dubbed the “100-year storm”. A high-resolution unstructured grid model (UnTRIM) was applied to simulate storm tide in the Chesapeake Bay. The application of an unstructured grid in the Bay offers the greatest flexibilities in representing complex estuarine geometry near the coast and encompassing a large modeling domain necessary for storm surge simulation. The resulting mesh has a total of 239,541 surface elements. The model was forced by 9 tidal harmonic constituents at the open boundary and a wind field generated by a parametric wind model. A hindcast simulation of Hurricane Isabel captures both peak storm tide and surge evolution in various sites of the Bay. Model diagnostic studies indicate that the high surge occurring in the upper Bay regions was mainly caused by the forced southerly wind, whereas the offshore surge and both the northeasterly and southeasterly winds influenced the lower Bay region more significantly. [Copyright &y& Elsevier]

The age concept is applied to an estuary to estimate time scales quantifying transport processes of dissolved substance for a spatially varying case. A real-time three-dimensional numerical model was applied to the tidal York River estuary, a western branch of the Chesapeake Bay, to calculate the age distribution for a substance released from the headwaters of tributaries of the estuary under different hydrological conditions. The mean age, residence time, and turnover time were computed through a series of numerical model experiments. Both mean age and residence time are functions of freshwater discharge. The model results show that substantial time is required for a substance discharged into the system at the headwaters of the tributaries to be transported to the downstream estuary. It takes about 2 months and 3 months for the substance discharged into the headwaters to be transported to the mouth of the estuary under high flow and mean flow conditions, respectively. The results provide useful information for understanding the transport processes in the estuary and can be used to estimate dissimilative capacity of the estuary for environmental assessment. [Copyright &y& Elsevier]

Abstract: Comparing with the studies on large estuarine systems, such as the Chesapeake Bay and the San Francisco Bay, the processes of stratification and transport in small and shallow estuaries are relatively less studied. The St. Lucie Estuary (SLE) is a riverine estuary located on the east coast of south Florida. It is small and shallow, with mean depth of 2.4m. To study the estuarine processes in the SLE, a hydrodynamic model was developed based on the Environmental Fluid Dynamics Code (EFDC) [Hamrick, J.M., 1992. A three-dimensional environmental fluid dynamics computer code: theoretical and computational aspects. The College of William and Mary, Virginia Institute of Marine Science, Special Report 317, 63 pp.]. The model was calibrated and verified using observational data obtained in 1999 and 2000, respectively. The model variables used for model data-comparisons are water elevation, velocity, temperature, and salinity. The model is then applied to study the hydrodynamic processes in the SLE. It is found that freshwater inflow plays a major role in the stratification and net flushing of the SLE. Stratification generally increases with freshwater inflow. But when the inflow is persistently large for a relatively long period, the estuary can suddenly change from very stratified to well mixed within a few tidal cycles and the stratification collapses. This finding suggests that large and persistent freshwater inflows do not always increase estuarine stratification. Instead, it may cause the stratification to collapse within a short period of time. In addition to gauged tributaries, ungauged lateral inflows can also be important to small and shallow estuaries like the SLE. Although small individually, the ungauged streams and surface runoffs can be a significant portion of the total inflow and affect salinity distribution significantly. Flushing time affects a wide range of hydrodynamic and water quality processes in the estuary. The model results indicate that commonly used formulas, such as the tidal prism formula and the Knudsen formula, may significantly underestimate the flushing time. [Copyright &y& Elsevier]

BACKGROUND The suicide risk of patients with cancer is higher than the general population. Our research aimed to explore the Surveillance, Epidemiology, and End Results (SEER) database to define incidence and quest risk factors for death of suicide in patients with Kaposi's sarcoma (KS) in the United States (US). MATERIAL AND METHODS We screened KS patients without human immunodeficiency virus status in the SEER database from 1980 to 2016, calculated the standardized mortality ratios of them by comparing the rates with those of the US general population from 1980 to 2016, and identified relevant suicide risk factors by univariable and multivariable logistic regression analyses. RESULTS The suicide rates of KS patients and US general population were 115.31 (110 suicides among 21 405 patients) and 15.1 per 100 000 person-years, respectively, thus the standardized mortality ratio was 7.64 (95% confidence interval [CI], 6.28-9.21). The multivariate analysis showed that black race (versus white race, hazard ratio [HR]: 0.43, 95% CI: 0.21-0.89, P=0.022), advanced age at diagnosis (≥55 years versus 18-44 years, HR: 0.31, 95% CI: 0.14-0.66, P=0.002), and chemotherapy (versus no chemotherapy, HR: 0.60, 95% CI: 0.37-0.96, P=0.032) were protective factors for suicide among KS patients. CONCLUSIONS Clinicians and caregivers can apply our findings to identify KS patients with high suicide risk characteristics (white race, age of 18-44 years, non-chemotherapy) and exert timely interventions during patient diagnosis, treatment, and follow-up to reduce the suicide rate in this population.

While genome-wide association studies (GWAS) and candidate gene approaches have identified many genetic variants that contribute to disease risk as main effects, the impact of genotype by environment (GxE) interactions remains rather under-surveyed. To explore the importance of GxE interactions for diabetes-related traits, a tool for Genome-wide Complex Trait Analysis (GCTA) was used to examine GxE variance contribution of 15 macronutrients and lifestyle to the total phenotypic variance of diabetes-related traits at the genome-wide level in a European American population. GCTA identified two key environmental factors making significant contributions to the GxE variance for diabetes-related traits: carbohydrate for fasting insulin (25.1% of total variance, P-nominal = 0.032) and homeostasis model assessment of insulin resistance (HOMA-IR) (24.2% of total variance, P-nominal = 0.035), n-6 polyunsaturated fatty acid (PUFA) for HOMA-β-cell-function (39.0% of total variance, P-nominal = 0.005). To demonstrate and support the results from GCTA, a GxE GWAS was conducted with each of the significant dietary factors and a control E factor (dietary protein), which contributed a non-significant GxE variance. We observed that GxE GWAS for the environmental factor contributing a significant GxE variance yielded more significant SNPs than the control factor. For each trait, we selected all significant SNPs produced from GxE GWAS, and conducted anew the GCTA to estimate the variance they contributed. We noted the variance contributed by these SNPs is higher than that of the control. In conclusion, we utilized a novel method that demonstrates the importance of genome-wide GxE interactions in explaining the variance of diabetes-related traits.