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Tundra and boreal ecosystems encompass the northern circumpolar permafrost region and are experiencing rapid environmental change with important implications for the global carbon (C) budget. We analysed multi-decadal time series containing 302 annual estimates of carbon dioxide (CO2) flux across 70 permafrost and non-permafrost ecosystems, and 672 estimates of summer CO2 flux across 181 ecosystems. We find an increase in the annual CO2 sink across non-permafrost ecosystems but not permafrost ecosystems, despite similar increases in summer uptake. Thus, recent non-growing-season CO2 losses have substantially impacted the CO2 balance of permafrost ecosystems. Furthermore, analysis of interannual variability reveals warmer summers amplify the C cycle (increase productivity and respiration) at putatively nitrogen-limited sites and at sites less reliant on summer precipitation for water use. Our findings suggest that water and nutrient availability will be important predictors of the C-cycle response of these ecosystems to future warming.

Background/Objectives There has been inconsistent relationships between serum vitamin D levels and lung function in previous studies. However, previous studies included patients with medical diseases, affecting both vitamin D levels and lung function. Considering this view of potential confounders, we investigated if vitamin D deficiency (VDD) is linked to lung function in health screening examinee without overt medical conditions. Subjects/Methods We conducted a cohort study on 68,457 healthy Koreans (36,759 males, mean age: 37.7 years) with a health examination in 2015. Measured forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were categorized in quartiles. To examine the relationships between VDD and lung function, adjusted odds ratios (aORs) for VDD were estimated by logistic regression. Results Median vitamin D level was 14.9 ng/mL. The prevalence of VDD (defined as Conclusions VDD was associated with decreased lung function in middle aged Korean men without overt medical conditions. VDD could be a modifiable risk factor for impaired lung function, in men but not in women., Author(s): Jonghoo Lee [sup.1] , Hye Kyeong Park [sup.2] , Min-Jung Kwon [sup.3] , Soo-Youn Ham [sup.4] , Si-Young Lim [sup.5] , Jae-Uk Song [sup.5] Author Affiliations: (1) Department of [...]

The Intermediate Disturbance Hypothesis (IDH) posits that maximal plant biodiversity is attained in environments characterized by moderate ecological disturbances. Although the applicability of the IDH to microbial diversity has been explored in a limited number of studies, there is a notable absence of experimental reports on whether soil microbial 'activity' demonstrates a similar response to the frequency or intensity of environmental disturbances. In this investigation, we conducted five distinct experiments employing soils or wetland sediments exposed to varying intensities or frequencies of disturbances, with a specific emphasis on disturbances associated with human activity, such as chemical contamination, hydrologic changes, and forest thinning. Specifically, we examined the effects of bactericide and heavy metal contamination, long-term drainage, tidal flow, and thinning management on microbial enzyme activities in soils. Our findings revealed that microbial enzyme activities were highest at intermediate disturbance levels. Despite the diversity in experiment conditions, each trial consistently demonstrated analogous patterns, suggesting the robustness of the IDH in elucidating microbial activities alongside diversity in soils. These outcomes bear significant implications for ecological restoration and management, as intermediate disturbance may expedite organic matter decomposition and nutrient cycles, crucial for sustaining ecosystem services in soils. [ABSTRACT FROM AUTHOR]

Background: Screening and treating healthcare workers (HCWs) for latent tuberculosis infection (LTBI) are essential for tuberculosis (TB) infection control. Adverse drug reactions (ADRs) to anti-TB drugs present challenges to patient safety and treatment completion. Objective: This study investigated the association between human leukocyte antigen (HLA) alleles and the risk of ADRs, especially drug hypersensitivity (DHS) and hepatotoxicity, in HCWs with LTBI receiving isoniazid (INH) and rifampin (RIF) therapy. Methods: Korean HCWs with LTBI who received a 3 month INH and RIF regimen were included in this study. HLA genotyping was performed on HCWs who experienced ADRs during treatment, as well as the control group consisted of individuals who did not develop ADRs. Results: Of the 67 patients, 29 (43.2%) experienced ADRs during INH and RIF therapy. The HLA-A*11:01 allele was more frequent in patients with DHS without hepatotoxicity (DSH+/H−) compared to the control group (DHS−/H−) (4/9, 44.4% vs. 3/38, 7.9%; odd ratio [OR], 8.554; 95% confidence interval [CI], 1.415–59.869; p = 0.018). Conversely, HLA-DPB1*05:01 was associated with an increased risk of hepatotoxicity regardless of DHS (10/20, 50% vs. 5/38, 13.2%; OR, 5.323; 95% CI, 1.493–21.518; p = 0.011). In the DHS with hepatotoxicity group (DHS+/H+), HLA-DPB1*05:01 was present in a higher proportion (3/5, 60% vs. 5/38, 13.2%; OR, 8.912; 95% CI, 1.110–92.993; p = 0.037), whereas HLA-A*11:01 was not observed in this group. Conclusions: The HLA-A*11:01 allele was associated with an increased risk of DHS without hepatotoxicity, whereas the HLA-DPB1*05:01 allele was associated with an increased risk of hepatotoxicity. [ABSTRACT FROM AUTHOR]

Aim: Hepatocellular carcinoma (HCC) is a major cause of cancer‐related death, with low survival rates worldwide. Fatty liver disease (FLD) significantly contributes to HCC. We studied the screening performance of different methods for identifying HCC in patients with FLD or with metabolic risk factors for FLD. Methods: Korean adults (n = 340 825) without a prior HCC diagnosis were categorized into four groups: normal (G1), ≥2 metabolic risk factors (G2), FLD (G3), and viral liver disease or liver cirrhosis (G4). The National Cancer Registry data were used to identify HCC cases within 12 months. We assessed the area under the receiver operating characteristic curve, sensitivity, specificity, and positive and negative predictive values of individual or combined screening methods. Results: In 93 HCC cases, 71 were identified in G4, whereas 20 cases (21.5%) in G2 and G3 combined where ultrasound and Fibrosis‐4 performed similarly to alpha‐fetoprotein and ultrasound. In G2, Fibrosis‐4 and ultrasound had the highest area under the receiver operating characteristic curve (0.93 [0.87–0.99]), whereas in G3, the combined screening methods had the highest area under the receiver operating characteristic curve (0.98 [0.95–1.00]). The positive predictive value was lower in G2 and G3 than in G4, but was >5% when restricted to a high Fibrosis‐4 score. Conclusions: More than 21% of HCC cases were observed in patients with diagnosed FLD or at risk of FLD with metabolic risk factors. Nevertheless, screening for HCC in individuals without cirrhosis or viral hepatitis yielded very low results, despite the potential value of the Fibrosis‐4 score in identifying individuals at high risk of HCC. [ABSTRACT FROM AUTHOR]

Glycated albumin (GA) reflects glycemic status for the past three weeks. GA level demonstrates a strong correlation with HbA1c level and is used as an adjunctive biomarker for diagnosis and monitoring of type 2 diabetes mellitus (T2DM). In this study, we validated the predictive performance of baseline GA for development of T2DM in healthy individuals in Korea. From August 2013 to September 2014, the medical records of 3,771 healthy Koreans were retrospectively reviewed. Each participant was categorized into tertiles based on initial GA level. During the follow-up period through May 2020, study participants were evaluated for T2DM using HbA1c, fasting glucose level, and a self-reported diagnosis history. Baseline GA level by tertile (T1 to T3) was 10.4 ± 0.8% (mean ± SD), 12.1 ± 0.3%, and 13.7 ± 0.9%, respectively. The median follow-up was 5.97 years, during which 4.9% (186 of 3,771) of the participants developed T2DM. After adjusting for confounding factors, the hazard ratio for the development of T2DM in the highest GA level group (T3) compared to the reference group (T1) was 2.46 (95% CI, 1.7 to 3.58, p < 0.001 for trend) with a Harrell's C index of 0.80 (95% CI, 0.76 to 0.83). Also, within highest group of baseline HbA1c and FG levels, higher GA levels were associated with an increased HRs for T2DM. In conclusion, Our study confirms that the risk of T2DM increases with baseline GA level. Additional follow-up of the cohort is warranted to investigate the correlations between GA and other clinical indicators including diabetic complications. [ABSTRACT FROM AUTHOR]

A consequence of land-use change and increasing human population in the United States and Central America has been an increase in nitrogen availability to coastal systems. Whereas many studies evaluate the influence of anthropogenically derived nutrients in modern oceans, fewer studies evaluate nutrient sources in coastal environments before the 1960s. This study used stable C and N isotope values of 35 big-claw snapping shrimps (Alpheus heterochaelis) and 48 ivory barnacles (Balanus eburneus) across the Gulf of Mexico, southeast coast of the United States, and the Caribbean over 121 y to examine whether human-derived nitrogen was used by coastal invertebrates. Gulf of Mexico and southeast U.S. collections were divided into preand post-1960 groups for analysis, roughly coinciding with the increase in fertilizer use associated with the 'Green Revolution' and large coastal population increases. For B. eburneus. [delta][.sup.15]N decreased in the coastal United States after 1960, but that was not the case for A. heterochaelis. [.sup.15]N-depleted fertilizer would be quickly incorporated by filter-feeding B. eburneus (via plankton). By contrast, the scavenging, omnivorous, A. heterochaelis would obtain more N from heterotrophic organic matter more isolated from the [.sup.15]N-depleted fertilizer signal. The Caribbean A. heterochaelis incorporated seagrass C and N. Local variation in N sources from the different collection areas was clearly observed. Although anthropogenic N has been making its way into the filter-feeding barnacles, it is not as apparent in the scavengers.KEY WORDS: stable isotopes, nitrogen, coastal nutrients, museum collections, INTRODUCTIONNutrient over-enrichment as a result of anthropogenic activity concentrated along the land-sea margin is a major stressor of aquatic, estuarine, and marine ecosystems and is increasing eutrophication of near-shore waters [...]