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Tidal wetlands provide valuable ecosystem services, including storing large amounts of carbon. However, the net exchanges of carbon dioxide (CO2) and methane (CH4) in tidal wetlands are highly uncertain. While several biogeochemical models can operate in tidal wetlands, they have yet to be parameterized and validated against high‐frequency, ecosystem‐scale CO2 and CH4 flux measurements across diverse sites. We paired the Cohort Marsh Equilibrium Model (CMEM) with a version of the PEPRMT model called PEPRMT‐Tidal, which considers the effects of water table height, sulfate, and nitrate availability on CO2 and CH4 emissions. Using a model‐data fusion approach, we parameterized the model with three sites and validated it with two independent sites, with representation from the three marine coasts of North America. Gross primary productivity (GPP) and ecosystem respiration (Reco) modules explained, on average, 73% of the variation in CO2 exchange with low model error (normalized root mean square error (nRMSE) <1). The CH4 module also explained the majority of variance in CH4 emissions in validation sites (R2 = 0.54; nRMSE = 1.15). The PEPRMT‐Tidal‐CMEM model coupling is a key advance toward constraining estimates of greenhouse gas emissions across diverse North American tidal wetlands. Further analyses of model error and case studies during changing salinity conditions guide future modeling efforts regarding four main processes: (a) the influence of salinity and nitrate on GPP, (b) the influence of laterally transported dissolved inorganic C on Reco, (c) heterogeneous sulfate availability and methylotrophic methanogenesis impacts on surface CH4 emissions, and (d) CH4 responses to non‐periodic changes in salinity. Plain Language Summary: Tidal wetlands play a crucial role in storing carbon, but there is uncertainty in how they absorb and release carbon dioxide and methane, two of the most important greenhouse gases. Existing models for tidal wetlands have yet to be thoroughly tested using high‐frequency data across diverse sites. The new model presented here was parameterized and validated using 13 years of data from five different tidal wetland sites with representation from the three marine coasts of North America. The model explained on average more than half of the variation in carbon dioxide and methane exchange with low model error across diverse tidal wetlands used in model validation. This is strong performance given the high variation in greenhouse gas fluxes in tidal wetlands, which are known to be biogeochemically complex environments. Our model helps in assessing the greenhouse gas budgets from diverse tidal wetlands and the ability of wetlands to combat climate change. An analysis of model results highlights the need for more research on how tidal pumping and pulse changes in soil and water chemistry, not just at the surface but also across soil layers, influence carbon dioxide and methane production and exchange. Key Points: We present a process‐based modeling approach to estimate greenhouse gas flux in tidal wetlands with representation from the three marine coasts of North AmericaModel validation showed that primary productivity, respiration and methane modules explained >50% of the variation in CO2 and CH4 exchangeThe PEPRMT‐Tidal‐CMEM model is a key advance toward constraining estimates of greenhouse gas emissions across diverse tidal wetlands [ABSTRACT FROM AUTHOR]

An investigation of alternative methods of managing lower division graphics courses is described. Nonexam grading time was reduced to nearly zero, creating time for professional growth, proposal development, and meaningful research. Grade profiles and attitudes of students taking the altered course are discussed. (KR)

Background and Objectives: In conjunction with a lack of primary and preventive care, many patients are treated in emergency departments (EDs) for sexually transmitted diseases (STDs).Goal: To epidemiologically characterize patients accessing an inner-city ED for treatment of STDs.Design: One hundred patients 17 years or older who were treated for an STD or who had conditions that were given syndromic or presumptive diagnoses of an STD participated in this prospective case series. Cases were identified on the basis of history and physical examination. Patients were interviewed to collect information on demographics, drug and alcohol use, current symptoms, self-medication, and health care access.Results: A total of 98% of patients who were approached participated. Two thirds of the participants were female. Women were more likely than men to have health insurance, Medical Assistance, and a regular source of health care. Injecting drug use was associated with a 5.3 increase in the odds ratio of delayed treatment seeking (P = 0.038). Effort to self-treat was associated with a 3.2 increase in the odds of delayed treatment seeking (P = 0.015). Being female was associated with a 4.1 increase in the odds of self-treatment (P = 0.009).Conclusion: This study identifies several potential barriers to appropriate health care access and use. The study also identifies the ED as a potential source of intervention for more comprehensive health care and an entry into the health care system for a difficult-to-reach patient population. [ABSTRACT FROM AUTHOR]

Tidal wetlands can be a substantial sink of greenhouse gases, which can be offset by variable methane (CH 4 ) emissions under certain environmental conditions and anthropogenic interventions. Land managers and policymakers need maps of tidal wetland CH 4 properties to make restoration decisions and inventory greenhouse gases. However, there is a mismatch in spatial scale between point-based sampling of porewater CH 4 concentration and its predictors, and the coarser resolution mapping products used to upscale these data. We sampled porewater CH 4 concentrations, salinity, sulfate (SO 4 2- ), ammonium (NH 4 + ), and total Fe using a spatially stratified sampling at 27 tidal wetlands in the United States. We measured porewater CH 4 concentrations across four orders of magnitude (0.05 to 852.9 μM). The relative contribution of spatial scale to variance in CH 4 was highest between- and within-sites. Porewater CH 4 concentration was best explained by SO 4 2- concentration with segmented linear regression (p < 0.01, R 2  = 0.54) indicating lesser sensitivity of CH 4 to SO 4 2- below 0.62 mM SO 4 2- . Salinity was a significant proxy for CH 4 concentration, because it was highly correlated with SO 4 2- (p < 0.01, R 2  = 0.909). However, salinity was less predictive of CH 4 with segmented linear regression (p < 0.01, R 2  = 0.319) relative to SO 4 2- . Neither NH 4 + , total Fe, nor relative tidal elevation correlated significantly with porewater CH 4 ; however, NH 4 + was positively and significantly correlated with SO 4 2- after detrending CH 4 for its relationship with SO 4 2- (p < 0.01, R 2  = 0.194). Future sampling should focus on within- and between-site environmental gradients to accurately map CH 4 variation. Mapping salinity at sub-watershed scales has some potential for mapping SO 4 2- , and by proxy, constraining spatial variation in porewater CH 4 concentrations. Additional work is needed to explain site-level deviations from the salinity-sulfate relationship and elucidate other predictors of methanogenesis. This work demonstrates a unique approach to remote team science and the potential to strengthen collaborative research networks., Competing Interests: Declaration of competing interest Erika L. Koontz, James R. Holmquist reports financial support was provided by NASA. Sarah M. Parker, Alice E. Stearns, Brian J. Roberts, Patricia Y. Oikawa, J. Patrick Megonigal reports financial support was provided by NASA. J. Patrick Megonigal, Amanda C. Spivak reports was provided by National Science Foundation. James R. Holmquist reports was provided by US Department of Energy. Andre S. Rovai, Robert R. Twilley reports was provided by US Army Engineer Research and Development Center. Amanda C. Spivak reports was provided by US Coastal Research Program. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Tropical wetlands and freshwaters are major contributors to the growing atmospheric methane (CH 4 ) burden. Extensive peatland drainage has lowered CH 4 emissions from peat soils in Southeast Asia, but the canals draining these peatlands may be hotspots of CH 4 emissions. Alternatively, CH 4 oxidation (consumption) by methanotrophic microorganisms may attenuate emissions. Here, we used laboratory experiments and a synoptic survey of the isotopic composition of CH 4 in 34 canals across West Kalimantan, Indonesia to quantify the proportion of CH 4 that is consumed and therefore not emitted to the atmosphere. We find that CH 4 oxidation mitigates 76.4 ± 12.0% of potential canal emissions, reducing emissions by ~70 mg CH 4 m -2 d -1 . Methane consumption also significantly impacts the stable isotopic fingerprint of canal CH 4 emissions. As canals drain over 65% of peatlands in Southeast Asia, our results suggest that CH 4 oxidation significantly influences landscape-scale CH 4 emissions from these ecosystems., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Methane (CH 4 ) is a potent greenhouse gas (GHG) with atmospheric concentrations that have nearly tripled since pre-industrial times. Wetlands account for a large share of global CH 4 emissions, yet the magnitude and factors controlling CH 4 fluxes in tidal wetlands remain uncertain. We synthesized CH 4 flux data from 100 chamber and 9 eddy covariance (EC) sites across tidal marshes in the conterminous United States to assess controlling factors and improve predictions of CH 4 emissions. This effort included creating an open-source database of chamber-based GHG fluxes (https://doi.org/10.25573/serc.14227085). Annual fluxes across chamber and EC sites averaged 26 ± 53 g CH 4 m -2  year -1 , with a median of 3.9 g CH 4 m -2  year -1 , and only 25% of sites exceeding 18 g CH 4 m -2  year -1 . The highest fluxes were observed at fresh-oligohaline sites with daily maximum temperature normals (MATmax) above 25.6°C. These were followed by frequently inundated low and mid-fresh-oligohaline marshes with MATmax ≤25.6°C, and mesohaline sites with MATmax >19°C. Quantile regressions of paired chamber CH 4 flux and porewater biogeochemistry revealed that the 90th percentile of fluxes fell below 5 ± 3 nmol m -2  s -1 at sulfate concentrations >4.7 ± 0.6 mM, porewater salinity >21 ± 2 psu, or surface water salinity >15 ± 3 psu. Across sites, salinity was the dominant predictor of annual CH 4 fluxes, while within sites, temperature, gross primary productivity (GPP), and tidal height controlled variability at diel and seasonal scales. At the diel scale, GPP preceded temperature in importance for predicting CH 4 flux changes, while the opposite was observed at the seasonal scale. Water levels influenced the timing and pathway of diel CH 4 fluxes, with pulsed releases of stored CH 4 at low to rising tide. This study provides data and methods to improve tidal marsh CH 4 emission estimates, support blue carbon assessments, and refine national and global GHG inventories., (© 2024 Smithsonian Institution and The Author(s). Global Change Biology published by John Wiley & Sons Ltd. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Purpose: Physiological aging is associated with microvascular dysfunction, including in the penis, and this may contribute to age-related erectile dysfunction (ED). Low-intensity extracorporeal shockwave therapy (Li-ESWT) is a non-invasive intervention for ED, but its effect on penile microvascular function, remains unclear. Our objectives are to (i) evaluate the effect of Li-ESWT (specifically radial type ESWT [rESWT]) on penile microvascular perfusion (PMP) in aging rats, (ii) elucidate a possible mechanism, and (iii) evaluate its impact on angiogenic and smooth muscle biomarkers in cavernosal tissue., Materials and Methods: Male rats (n=9; 15-18 months) were anesthetized and subjected to rESWT while monitoring PMP. The nitric oxide (NO) pathway involvement was assessed by measuring the effect of rESWT on PMP following an intracavernosal injection of N(G)-nitroarginine methyl ester (L-NAME) (NO synthase inhibitor). To elucidate the cellular mechanism, another group of rats received repeated rESWT (n=4) or no treatment (n=4) three times/week for two weeks. Rats were euthanized at the end of the study and penile tissues were analyzed for angiogenic markers (vascular endothelial growth factor-A [VEGF-A], endothelial nitric oxide synthase [eNOS]) and smooth muscle content (α-actin) using immunostaining, Western blot, and quantitative polymerase chain reaction (qPCR)., Results: rESWT resulted in more than a 2-fold increase in PMP (from 68.5 arbitrary units; 163.7 AU). L-NAME injection produced a <40%-50% decrease (185.3 to 101.0 AU) in rESWT-induced PMP response. Immunostaining revealed increased α-actin, eNOS, and VEGF-A in the cavernosum and these findings were confirmed by qPCR and Western blot results., Conclusions: rESWT improved PMP, which may be mediated via increased VEGF expression, which stimulates the NO/cyclic guanosine monophosphate pathway, resulting in sustained PMP. rESWT devices could offer a safe, non-invasive treatment for age-related ED., Competing Interests: The authors have nothing to disclose., (Copyright © 2024 Korean Society for Sexual Medicine and Andrology.)

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only curative option for high-risk myeloid malignancies. Post-transplant cyclophosphamide (PT-Cy) has proven to be effective for graft versus host disease (GVHD) prophylaxis. Given that graft-versus-tumor (GVT) effect plays a major role in reducing the risk of disease relapse, the application of PT-Cy must balance the risk of relapse. Mixed chimerism (MC) refers to a state of concurrent presence of recipient and donor cells post allo-HSCT which may precede relapse disease., Objective: We investigated the impact of PT-Cy on early MC (EMC) and disease relapse in patients with a myeloid malignancy post allo-HSCT., Study Design: This retrospective single-center study included patients that underwent allo-HSCT between 2015 and 2021. Patient and disease characteristics were collected from the electronic health records. EMC was defined as <95% donor cells at day 90-120 post allo-HSCT., Results: A total of 144 patient that received an allo-HSCT were included in the study. One hundred and eight (75%) patients received PT-Cy as part of the GVHD prophylaxis regimen. The majority underwent allo-HSCT for acute myeloid leukemia (62%) or myelodysplastic syndrome (31%). Sixty-five percent received allo-HSCT from a matched unrelated donor transplant and 65% received a myeloablative conditioning regimen. A lower rate of chronic GVHD (p = 0.03) and a higher rate of EMC (p = 0.04) were observed in patients that received PT-Cy. PT-Cy was not associated with overall survival (OS) and relapse-free survival (RFS). Multivariable analysis identified measurable residual disease status (p = 0.003), hematopoietic cell transplantation-specific comorbidity index (p = 0.012) and chronic GVHD (p = 0.006) as independent prognostic variables for OS. AML-adverse risk (p = 0.004) and EMC (p = 0.018) were independently prognostic for RFS. While EMC overall was not significantly associated with higher risk of relapse, EMC was associated with shorter RFS within adverse-risk AML patients., Conclusion: Our study shows that PT-Cy was associated with an increased risk of EMC. The predictive value of EMC for relapse remains unclear and may depend on the underlying disease, which should be validated in a larger cohort., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder that has been ranked as the 4th leading cause of disability worldwide. Past clinical and laboratory evidence has confirmed that abnormalities of the hypothalamic-pituitary-adrenal (HPA)-axis are involved in MDD development. In this study, we took advantage of corticosterone treatment of PC12 cells as a model to identify genes regulated by HPA-axis hormones. Next-generation RNA-Seq technology was utilized to explore genome-wide differentially expressed gene profiles between control and corticosterone treated PC12 cells. 1,274 genes with at least two-fold expression level change were identified. Gene ontology analysis showed that the top enriched biological processes included response to glucocorticoid signaling, apoptosis, cell division/DNA replication, and neuron projection/axon guidance, highly consistent with phenotypes of PC12 cells treated with corticosterone. Taken together, RNA-seq data is reliable and comprehensive, thus providing a valuable resource for understanding underlying mechanisms of glucocorticoid-induced neuron malfunction., Competing Interests: None., (IJCEP Copyright © 2018.)

Objectives: Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted disease, but there is limited data on its epidemiology among urban populations. The urban Emergency Department (ED) is a potential venue for surveillance as it predominantly serves an inner city minority population. We evaluate the seroprevalence and factors associated with HSV-2 infection among patients attending the Johns Hopkins Hospital Adult Emergency Department (JHH ED)., Methods: An identity unlinked-serosurvey was conducted between 6/2007 and 9/2007 in the JHH ED; sera were tested by the Focus HerpeSelect ELISA. Prevalence risk ratios (PRR) were used to determine factors associated with HSV-2 infection., Results: Of 3,408 serum samples, 1,853 (54.4%) were seropositive for HSV-2. Females (adjPRR  = 1.47, 95% CI 1.38-1.56), non-Hispanic blacks (adjPRR  = 2.03, 95% CI 1.82-2.27), single (adjPRR  = 1.15, 95% CI 1.07-1.25), divorced (adjPRR  = 1.28, 95% CI 1.15-1.41), and unemployed patients (adjPRR  = 1.13, 95% CI 1.05-1.21) had significantly higher rates of HSV-2 infection. Though certain zip codes had significantly higher seroprevalence of HSV-2, this effect was completely attenuated when controlling for age and gender., Conclusions: Seroprevalence of HSV-2 in the JHH ED was higher than U.S. national estimates; however, factors associated with HSV-2 infection were similar. The high seroprevalence of HSV-2 in this urban ED highlights the need for targeted testing and treatment. Cross-sectional serosurveys in the urban ED may help to examine the epidemiology of HSV-2.

Early diagnosis of persons infected with human immunodeficiency virus (HIV) through diagnostic testing and screening is a critical priority for individual and public health. Emergency departments (EDs) have an important role in this effort. As EDs gain experience in HIV testing, it is increasingly apparent that implementing testing is conceptually and operationally complex. A wide variety of HIV testing practice and research models have emerged, each reflecting adaptations to site-specific factors and the needs of local populations. The diversity and complexity inherent in nascent ED HIV testing practice and research are associated with the risk that findings will not be described according to a common lexicon. This article presents a comprehensive set of terms and definitions that can be used to describe ED-based HIV testing programs, developed by consensus opinion from the inaugural meeting of the National ED HIV Testing Consortium. These definitions are designed to facilitate discussion, increase comparability of future reports, and potentially accelerate wider implementation of ED HIV testing.

Objective(s): : To determine the effect of viral suppression on cross-sectional incidence testing., Methods: : In 2001 and 2003, patients entering the Johns Hopkins Hospital (JHH) Emergency Department (ED) were enrolled into an interview-based identity-unlinked serosurvey. All HIV-positive samples were tested by the Vironostika-less sensitive (LS) enzyme immunoassay (EIA) (Organon-Teknika, Charteston, SC) and an avidity assay to determine recent HIV infection. Additionally 16 samples from 8 previously characterized elite suppressors (ES) were tested by cross-sectional incidence assays., Results: : HIV prevalence was 12% for the 2001 survey and 11% for the 2003 survey. Of the HIV-infected subjects, 18% did not know they were infected. The Vironostika-LS EIA determined that 6% (11 of 183) and 7% (17 of 243) of HIV-positive individuals in 2001and 2003, respectively, were recently infected. Avidity testing confirmed that 6 of 11 in 2001 and 5 of 17 in 2003 were newly infected, leaving 17 discrepant samples. All 17 discrepant samples were Western blot-positive and viral load undetectable, and 7 of 17 had antiretroviral drugs (ARVs) in their serum. Ten individuals were virally suppressed without ARVs and seemed incident by the Vironostika-LS EIA but chronic by avidity testing. These 10 subjects had similar testing profiles to the known 16 ES samples, because 9 of 16 were incident by the Vironostika-LS EIA and 0 of 16 were incident by avidity testing., Conclusions: : By removing the viral load-negative individuals and confirming the initial Vironostika-LS EIA results by avidity testing, the incidence estimate was lowered from 1.73% to 0.94% per year in 2001 and from 1.90% to 0.56% per year in 2003. Viral suppression affects the performance of the cross-sectional incidence tests, which rely on antibody titer. In addition, 2% (10 of 426) of all HIV-infected individuals who use the JHH ED for medical care seem to suppress HIV to undetectable levels without ARVs.

Objective: To assess the feasibility and effectiveness of an ED-based tuberculosis (TB) screening program., Methods: A TB screening program of adult ED patients was conducted at a university hospital ED with 46,000 annual visits that serves a poor urban community. Patients were screened on weekdays during business hours. ED patients were counseled about the disease and the screening procedure and, after consent, purified protein derivative (PPD) tests were placed. Patients returned in 48-72 hours for reaction reading and post-test counseling. PPD-positive patients received a physical examination, chest x-ray, and HIV testing and were referred to a city TB clinic for possible treatment., Results: Overall, 873 patients were counseled, 630 were eligible for screening, and 374 (59.4%) consented to PPD testing. Of the 203 (54.1%) who returned, 32 (15.8%) were PPD-positive. No active case was detected, but 26 patients were referred to the health department. Eighteen kept their appointments and all 13 who were started on therapy completed treatment. Targeted screening of groups aged 55 years or more, nonwhite groups, and those with other high-risk factors would detect 84% of PPD-positive cases while testing only 48% of eligible patients., Conclusion: An ED-based TB screening program is feasible and can identify many patients requiring treatment. Targeted screening of high-risk groups could reduce the program cost, but would miss some cases.

Study Objective: We sought to (1) determine whether some emergency departments could play an important role in the national strategy of early HIV detection through the implementation of a voluntary HIV screening program and (2) describe the experience with standard and rapid HIV testing., Methods: Consenting adults were enrolled during 3 distinct phases between 1993 and 1995 for the assessment of routine testing only, routine versus rapid testing, and rapid testing only. Patients administered the rapid test were given information at the time of the visit. We assessed the cost of the program., Results: Of 3,048 patients approached, 1,448 (48%) consented, 981 to standard and 467 to rapid testing. Of these, 6.4% and 3.2%, respectively, were newly identified as being HIV seropositive. More than twice as many new infections were diagnosed among those discharged from the ED as among those admitted (55 versus 21). Even among those previously tested, 5% proved seropositive. The mean+/-SD time to obtain results for the rapid assay performed in the hospital's main laboratory was 107+/-52 minutes, with 55% leaving the ED before receiving the results. Rapid assays performed in the ED satellite laboratory required 48+/-37 minutes, and only 20% left before getting the results. Follow-up among HIV-seropositive patients was 64% for the standard protocol and 73% for the rapid protocol (P >. 20). The prearranged HIV clinic intake appointment was kept by 62%. Rapid test sensitivity and specificity were 100% and 98.9%, respectively, with 5 initial false-positives and no false-negatives. Cost per patient enrolled and counseled was $38. Cost per infection detected was $601 for the routine test and $1,124 with the rapid test; these prices are competitive with those incurred at other sites., Conclusion: Emergency department-based HIV testing was well accepted and detected a significant number of new HIV infections earlier than might have otherwise been, particularly among patients sent home. The rapid test is best performed on-site and is very sensitive. Confirmation of initial results is required because of the occurrence of occasional false-positive results. With relatively high HIV detection and return rates, it is evident that some EDs could play a major role in the national strategy of early HIV detection.