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We combined year-round eddy covariance with biometry and biomass harvests along a chronosequence of boreal forest stands that were 1, 6, 15, 23, 40, 74, and 154 years old to understand how ecosystem production and carbon stocks change during recovery from stand-replacing crown fire. Live biomass (Clive) was low in the 1 and 6 year old stands, and increased following a logistic pattern to high levels in the 74 and 154year old stands. Carbon stocks in the forest floor (Cforest floor) and coarse woody debris (CCWD) were comparatively high in the 1year old stand, reduced in the 6 through 40year old stands, and highest in the 74 and 154year old stands. Total net primary production (TNPP) was reduced in the 1 and 6year old stands, highest in the 23 through 74year old stands and somewhat reduced in the 154year old stand. The NPP decline at the 154year old stand was related to increased autotrophic respiration rather than decreased gross primary production (GPP). Net ecosystem production (NEP), calculated by integrated eddy covariance, indicated the 1 and 6 year old stands were losing carbon, the 15year old stand was gaining a small amount of carbon, the 23 and 74year old stands were gaining considerable carbon, and the 40 and 154year old stands were gaining modest amounts of carbon. The recovery from fire was rapid; a linear fit through the NEP observations at the 6 and 15year old stands indicated the transition from carbon source to sink occurred within 11-12 years. The NEP decline at the 154year old stand appears related to increased losses from Clive by tree mortality and possibly from Cforest floor by decomposition. Our findings support the idea that NPP, carbon production efficiency (NPP/GPP), NEP, and carbon storage efficiency (NEP/TNPP) all decrease in old boreal stands. © 2010 Blackwell Publishing Ltd.

We deployed a mesonet of year-round eddy covariance towers in boreal forest stands that last burned in ∼1850, ∼1930, 1964, 1981, 1989, 1998, and 2003 to understand how CO 2 exchange and evapotranspiration change during secondary succession. We used MODIS imagery to establish that the tower sites were representative of the patterns of secondary succession in the region, and Landsat images to show that the individual stands have changed over the last 22 years in ways that match the spatially derived trends. The eddy covariance towers were well matched, with similar equipment and programs, which maximized site-to-site precision and allowed us to operate the network in an efficient manner. The six oldest sites were fully operational for ∼90% of the growing season and ∼70% of the dormant season from 2001 or 2002 to 2004, with most of the missing data caused by low battery charge or bad signals from the sonic anemometers. The rates of midday growing-season CO2 uptake recovered to preburn levels within 4 years of fire. The seasonality of land-atmosphere exchange and growing-season length changed markedly with stand age. The foliage in the younger stands (1989, 1998, and 2003 burns) was almost entirely deciduous, which resulted in comparatively short growing seasons that lasted ∼65 days. In contrast, the older stands (1850, 1930, 1964, and 1981) were mostly evergreen, which resulted in comparatively long growing seasons that lasted ∼130 days. The eddy covariance mesonet approach we describe could be used within the context of other ecological experimental designs such as controlled manipulations and gradient comparisons. © 2006 Blackwell Publishing Ltd.

We used a 10-year record of the CO2 flux by an old growth boreal forest in central Manitoba (the Northern Old Black Spruce Site (NOBS)), a ∼150-year-old Picea mariana [Mill.] stand) to determine whether and how whole-forest CO2 flux is related to tree ring width. We compared a 37-year ring width chronology collected at NOBS to a second chronology that was collected at a nearby Black Spruce stand with a different disturbance history, and also to three measures of annual whole-forest photosynthesis [gross ecosystem production (GEP)], two measures of annual respiration (R), and one measure of annual carbon balance [net ecosystem production (NEP)]. The year-to-year ring width fluctuations were well correlated between the two sites; increasing our confidence in the NOBS chronology and implying that ring width variation is driven and synchronized by the physical environment. Both chronologies exhibited serial correlation, with a fluctuation in ring width that had an apparent periodicity of ∼7 years. Neither chronology was correlated with variation in annual precipitation or temperature. Ring width and NEP increased, while R decreased from 1995 to 2004. GEP either remained constant or decreased from 1995 to 2004, depending on which measure was considered. The lack of relationship between ring width and GEP may indicate that ring growth is controlled almost entirely by something other than carbon uptake. Alternative explanations for the ring width chronologies include the possibility that wood production varies as a result of shifts in respiration, or that an unidentified aspect of the environment, rather than the balance between GEP and respiration, controls wood production. The serial correlation in ring width may be related to increases and decreases in carbohydrate pools, or to gradual changes in nutrient availability, pathogens, herbivores, soil frost or soil water table. The cause or causes of serial correlation, and the controls on the allocation of photosynthate to wood production, emerge as critical uncertainties for efforts in predicting the carbon balance of boreal ecosystems and inferring past climate from tree rings. © 2006 Blackwell Publishing Ltd.

Melasma is a skin pigmentation disorder that lacks consistent treatment success, despite various methods used. Tranexamic acid (TXA) has shown hypopigmentation properties, but whether its administration should be combined with standard treatment has yet to be clarified. We aimed to perform an investigation of the effectiveness and safety of oral TXA as an adjuvant to triple combination cream (TCC) treatment in melasma. We searched PubMed, Embase and Cochrane (CENTRAL) for studies that compared TCC + adjuvant TXA to TCC treatment alone in patients with melasma. Outcomes of interest included change from the baseline Melasma Area and Severity Index (MASI) score, recurrence of melasma and adverse events. Statistical analysis was performed using R Studio 4.3.2. Four trials involving 490 patients were included. In the pooled analysis, the decrease from baseline in MASI score [mean difference -3.10, 95% confidence interval (CI) -5.85 to -0.35] was significantly higher in patients treated with oral TXA as an adjuvant to TCC compared with TCC alone. Melasma recurrence [risk ratio (RR) 0.28; 95% CI 0.16-0.49] was significantly lower in the group treated with TCC and TXA. Regarding erythema (RR 0.63, 95% CI 0.34-1.17) and burning (RR 0.59, 95% CI 0.30-1.17), no statistically significant difference was found. This meta-analysis demonstrated statistically significant benefits of TCC + TXA combination treatment compared with TCC alone. Furthermore, the results suggest that the addition of TXA to TCC treatment may reduce melasma recurrence., Competing Interests: Conflicts of interest The authors declare no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Association of Dermatologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Introduction: Transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) are established interventions for alleviating symptoms and enhancing survival in individuals with severe aortic stenosis (AS). However, the long-term outcomes and incidence of reintervention associated with TAVI and SAVR remain uncertain., Methods: We conducted a systematic review and meta-analysis to compare the incidence of reintervention in TAVI versus SAVR. PubMed, Embase, and Cochrane databases were searched for randomized controlled trials (RCTs). Risk ratios (RR) and 95% confidence intervals (CI) were pooled with a random-effects model. A p-value < 0.05 was considered statistically significant., Results: Nine RCTs were included, with 5144 (50.9%) patients randomized to TAVI. Compared with SAVR, TAVI increased reinterventions (RR 1.89; 95% CI 1.29-2.76; p < 0.01) and the need for pacemakers (RR 1.91; 95% CI 1.49-2.45; p < 0.01). In addition, TAVI significantly reduced the incidence of new-onset atrial fibrillation (RR 0.43; 95% CI 0.32- 0.59; p < 0.01). There were no significant differences in all-cause mortality (RR 1.04; 95% CI 0.92-1.16; p = 0.55), cardiovascular mortality (RR 1.04; 95% CI 0.94-1.17; p = 0.44), stroke (RR 0.97; 95% CI 0.80-1.17; p = 0.76), endocarditis (RR 0.96; 95% CI 0.70-1.33; p = 0.82), and myocardial infarction (RR 1.06; 95% CI 0.79-1.41; p = 0.72) between groups., Conclusions: In patients with severe AS, TAVI significantly increased the incidence of reinterventions and the need for pacemakers as compared with SAVR., (© 2024. The Author(s), under exclusive licence to The Japanese Association for Thoracic Surgery.)

In patients with stable atherosclerotic cardiovascular disease, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is) have shown a 50% to 60% reduction in low-density lipoprotein cholesterol (LDL-C) from baseline when added to high-intensity statin therapy. However, less is known about the impact of PCSK9is in the setting of an acute coronary syndrome (ACS). Therefore, we performed a systematic review and meta-analysis comparing PCSK9is with placebo in the setting of ACS added to guideline-directed high-intensity or maximally tolerated statin therapy. We included randomized controlled trials with initiation of a PCSK9i or placebo within 1 week of presentation or percutaneous coronary intervention for ACS. PubMed, EMBASE, and Cochrane Central were searched. This study followed the Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) recommendations. A total of 6 randomized controlled trials were included, with a total of 996 patients, of whom 503 (50.5%) received PCSK9is. The mean follow-up ranged from 4 to 52 weeks. The LDL-C (mean difference [MD] -44.0 mg/100 ml, CI -54.3 to -33.8, p <0.001) and lipoprotein (a) levels (MD -24.0 nmol/L, confidence interval [CI] -43.0 to -4.9, p = 0.01) were significantly lower at follow-up with PCSK9is. Similarly, the total cholesterol (MD -49.2 mg/100 ml, CI -59.0 to -39.3), triglycerides (MD -19.0 mg/100 ml, CI -29.9 to -8.2), and apolipoprotein B (MD -33.3 mg/100 ml, CI -44.4 to -22.1) were significantly reduced with PCSK9is. In conclusion, in patients with ACS, early initiation of PCSK9i added to statin significantly reduces LDL-C and lipoprotein (a) levels compared with placebo. Whether the differences in these atherogenic lipoproteins translate into a reduction in clinical end points is yet to be determined., Competing Interests: Declaration of competing interest Dr. Leucker has received grants from American Heart Association Career Development Award, National Institutes of Health, Merck, and Amgen. The remaining authors have no competing interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Cardiac arrhythmias, including ventricular tachycardia (VT), stand as a significant threat to health, often leading to mortality and sudden cardiac death. While conventional treatments for VT exhibit efficacy, cases of refractory VT pose challenges. Stereotactic Arrhythmia Radioablation (STAR) offers a novel approach, delivering precise high-dose radiation to well-defined targets with minimal collateral damage. This study explores the potential of STAR as an alternative therapy, especially for high-risk patients or those with refractory VT., Methods: This research reviews ongoing studies and preliminary investigations into the evaluation of the efficacy and safety of STAR. The method involves targeted radiation delivery, assessing reductions in VT recurrence and the early safety profile in refractory VT patients. However, given STAR's early stage and limited clinical evidence, cautious interpretation is advised., Results: Preliminary findings indicate a reduction in VT recurrence with STAR, suggesting promise as a therapeutic option. Early safety profiles are encouraging, but definitive statements on efficacy and safety require further investigation. Positive initial outcomes underscore the need for additional data and long-term studies., Conclusion: Stereotactic Arrhythmia Radioablation is recently emerging as a promising treatment for refractory VT. While early results are encouraging, careful interpretation is needed, due to STAR's early stages. Ongoing investigations are critical for a comprehensive understanding of its long-term efficacy and tolerability. This review provides fundamental insights into STAR's background, principles, pre-treatment procedures, clinical implications, and toxicity, setting the stage for future research in this evolving therapeutic field., Competing Interests: There are no conflicts of interest to report. This is a review article. No human subjects were involved, and no consent was needed., (© 2023 The Authors. Health Science Reports published by Wiley Periodicals LLC.)

Introduction: The relationship between cardiovascular disorders and nonalcoholic fatty liver disease (NAFLD) has been extensively studied. To better pool this data and make a more definite conclusion, we performed a meta-analysis to evaluate the association between NAFLD and the thickness of media and intima of carotid artery (CIMT) and cardiovascular disorders., Methods: We searched PubMed, Ovid, Scopus, ProQuest, Web of Science, and the Cochrane Library, and analyzed the pooled data using R studio and the "metafor" package., Results: The final analysis included a total of 59 studies with 16,179 cases and 26,120 control individuals. NAFLD was shown to be associated with an increase of 0.1231 mm (20.6%) in carotid artery intima-media thickness (CIMT) ( p  = 0.002, 95% confidence interval [CI]: 0.0462-0.2000) in individuals with NAFLD. The prevalence of atherosclerotic plaques in the carotid arteries and the occurrence of NAFLD are significantly correlated, according to a meta-analysis based on 17 distinct studies ( p  = 0.001, 1.28-1.43, 95% CI, odds ratio = 1.356)., Conclusion: Patients with increased CIMT are considerably more likely to have NAFLD. Large prospective investigations are required to corroborate these findings and their prognostic significance, along with the effectiveness of the available interventions., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. Health Science Reports published by Wiley Periodicals LLC.)

Some rhizomatous grass and sedge species form tussocks that impact ecosystem structure and function. Despite their importance, tussock development and size controls are poorly understood due to the decadal to centennial timescales over which tussocks form. We explored mechanisms regulating tussock development and size in a ubiquitous arctic tussock sedge (Eriophorum vaginatum) using field observations and a mass balance model coupled with a tiller population model. Model-data fusion was used to quantify parameter and prediction uncertainty, determine model sensitivity, and test hypotheses on the factors regulating tussock size. The model accurately captured the dynamics of tussock development, characteristics, and size observed in the field. Tussock growth approached maximal size within several decades, which was determined by feedbacks between the mass balance of tussock root necromass and density-dependent tillering. The model also predicted that maximal tussock size was primarily regulated by tiller root productivity and necromass bulk density and less so by tiller demography. These predictions were corroborated by field observations of tussock biomass and root characteristics. The study highlights the importance of belowground processes in regulating tussock development and size and enhances our understanding of the influence of tussocks on arctic ecosystem structure and function., (© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.)

Despite the importance of high-latitude surface energy budgets (SEBs) for land-climate interactions in the rapidly changing Arctic, uncertainties in their prediction persist. Here, we harmonize SEB observations across a network of vegetated and glaciated sites at circumpolar scale (1994-2021). Our variance-partitioning analysis identifies vegetation type as an important predictor for SEB-components during Arctic summer (June-August), compared to other SEB-drivers including climate, latitude and permafrost characteristics. Differences among vegetation types can be of similar magnitude as between vegetation and glacier surfaces and are especially high for summer sensible and latent heat fluxes. The timing of SEB-flux summer-regimes (when daily mean values exceed 0 Wm -2 ) relative to snow-free and -onset dates varies substantially depending on vegetation type, implying vegetation controls on snow-cover and SEB-flux seasonality. Our results indicate complex shifts in surface energy fluxes with land-cover transitions and a lengthening summer season, and highlight the potential for improving future Earth system models via a refined representation of Arctic vegetation types., (© 2022. The Author(s).)

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical changes to ecosystems, fire danger is increasing, and fires are having increasingly devastating impacts on human health, infrastructure, and ecosystem services. Increasing fire danger is a vexing problem that requires deep transdisciplinary, trans-sector, and inclusive partnerships to address. Here, we outline barriers and opportunities in the next generation of fire science and provide guidance for investment in future research. We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the "firehose" of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways toward mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future., (Published by Oxford University Press on behalf of National Academy of Sciences 2022.)

Fire is an important ecological disturbance that can reset ecosystems and initiate changes in plant community composition, ecosystem biogeochemistry, and primary productivity. As herbivores rely on primary producers for food, changes in vegetation may alter plant-herbivore interactions with important-but often unexplored-feedbacks to ecosystems. Here we examined the impact of post-fire changes in plant community composition and structure on habitat suitability and rodent herbivore activity in response to a large, severe, and unprecedented fire in northern Alaskan tundra. In moist acidic tundra where the fire occurred, tundra voles (Microtus oeconomus) are the dominant herbivore and rely on the tussock forming sedge Eriophorum vaginatum for both food and nesting material. Tundra voles were 10 times more abundant at the burned site compared with nearby unburned tundra 7-12 years after the fire. Fire increased the habitat suitability for voles by increasing plant productivity and biomass, food quality, and cover through both taller vegetation and increased microtopography. As a result of elevated vole abundance, Eriophorum mortality caused by vole herbivory was two orders of magnitude higher than natural mortality and approached the magnitude of the mortality rate resulting directly from the fire. These findings suggest that post-fire increases in herbivore pressure on Eriophorum could, in turn, disrupt graminoid recovery and enhance shrub encroachment. Tundra state transitions from graminoid to shrub dominated are also evident following other disturbances and fertilization experiments, suggesting that as Arctic temperatures rise, greater available nutrients and increased frequencies of large-scale disturbances may also alter plant-animal interactions with cascading impacts on plant communities and ecosystem function., (© 2022 The Ecological Society of America.)

The main objective of this study was to evaluate biogeographical hypotheses of diversification and connection between isolated savannas north (Amazonian savannas) and south (Cerrado core) of the Amazon River. To achieve this, we used genomic markers (genotyping-by-sequencing) to evaluate the genetic structure, population phylogenetic relationships and historical range shifts of four Neotropical passerines with peri-Atlantic distributions: the narrow-billed woodcreeper (Lepidocolaptes angustirostris), the plain-crested elaenia (Elaenia cristata), the grassland sparrow (Ammodramus humeralis) and the white-banded tanager (Neothraupis fasciata). Population genetic analyses indicated that landscape (e.g., geographic distance, landscape resistance and percentage of tree cover) and climate metrics explained divergence among populations in most species, but without indicating a differential role between current and historical factors. Our results did not fully support the hypothesis that isolated populations in Amazonian savannas have been recently derived from the Cerrado core domain. Intraspecific phylogenies and gene flow analyses supported multiple routes of connection between the Cerrado and Amazonian savannas, rejecting the hypothesis that the Atlantic corridor explains the peri-Atlantic distribution. Our results reveal that the biogeographical history of the region is complex and cannot be explained by simple vicariant models., (© 2022 John Wiley & Sons Ltd.)

Uncertainties surrounding tree carbon allocation to growth are a major limitation to projections of forest carbon sequestration and response to climate change. The prevalence and extent to which carbon assimilation (source) or cambial activity (sink) mediate wood production are fundamentally important and remain elusive. We quantified source-sink relations across biomes by combining eddy-covariance gross primary production with extensive on-site and regional tree ring observations. We found widespread temporal decoupling between carbon assimilation and tree growth, underpinned by contrasting climatic sensitivities of these two processes. Substantial differences in assimilation-growth decoupling between angiosperms and gymnosperms were determined, as well as stronger decoupling with canopy closure, aridity, and decreasing temperatures. Our results reveal pervasive sink control over tree growth that is likely to be increasingly prominent under global climate change.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km 2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km 2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

The COVID-19 pandemic has created an unprecedented need for epidemiological monitoring using diverse strategies. We conducted a project combining prevalence, seroprevalence, and genomic surveillance approaches to describe the initial pandemic stages in Betim City, Brazil. We collected 3239 subjects in a population-based age-, sex- and neighborhood-stratified, household, prospective; cross-sectional study divided into three surveys 21 days apart sampling the same geographical area. In the first survey, overall prevalence (participants positive in serological or molecular tests) reached 0.46% (90% CI 0.12-0.80%), followed by 2.69% (90% CI 1.88-3.49%) in the second survey and 6.67% (90% CI 5.42-7.92%) in the third. The underreporting reached 11, 19.6, and 20.4 times in each survey. We observed increased odds to test positive in females compared to males (OR 1.88 95% CI 1.25-2.82), while the single best predictor for positivity was ageusia/anosmia (OR 8.12, 95% CI 4.72-13.98). Thirty-five SARS-CoV-2 genomes were sequenced, of which 18 were classified as lineage B.1.1.28, while 17 were B.1.1.33. Multiple independent viral introductions were observed. Integration of multiple epidemiological strategies was able to adequately describe COVID-19 dispersion in the city. Presented results have helped local government authorities to guide pandemic management., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Silva, Menezes, Moreira, Torres, Fonseca, Moreira, Alves, Alves, Amaral, Coelho, Saraiva Duarte, da Rocha, de Almeida, de Araújo, de Oliveira, de Oliveira, Zolini, de Sousa, de Souza, de Souza, Ferreira, Lehmkuhl Gerber, Guimarães, Maia, Marim, Miguita, Monteiro, Neto, Pugêdo, Queiroz, Queiroz, Resende-Moreira, Santos, Souza, Voloch, Vasconcelos, de Aguiar and Souza.)

Background: Patients with atrial fibrillation and bioprosthetic valves are at high risk for thromboembolic events. The pooled efficacy and safety of non-vitamin K oral anticoagulants (NOACs), as a class, relative to warfarin in this population is not well-known. We aimed to compare the efficacy and safety of NOACs relative to warfarin in patients with bioprosthetic valves or valve repair., Methods: We systematically searched EMBASE, PubMed, and Cochrane databases for randomized controlled trials comparing NOACs to warfarin in patients with atrial fibrillation and bioprosthetic valves or valve repair. We pooled outcomes for stroke or systemic embolism, ischemic stroke, hemorrhagic stroke, and major bleeding., Results: We included 4 trials with 1379 patients, of whom 723 (52.4%) received a NOAC. Mean follow-up ranged from 90 days to 2.8 years. In the pooled analysis, stroke or systemic embolism was significantly lower in patients treated with NOACs (1.9%) compared with warfarin (3.7%) (odds ratio [OR] 0.43; 95% confidence interval [CI] 0.22-0.85; P = .02). Ischemic stroke (OR 0.72; 95% CI 0.18-2.93), hemorrhagic stroke (OR 0.18; 95% CI 0.03-1.05), cardiovascular death (OR 0.78; 95% CI 0.38-1.62), and all-cause mortality (OR 0.94; 95% CI 0.55-1.62) were not significantly different among groups. Major bleeding was significantly lower in patients treated with NOAC (2.8%) compared with warfarin (4.7%) (OR 0.49; 95% CI 0.28-0.88; P = .02)., Conclusions: In patients with atrial fibrillation and bioprosthetic valves or valve repair, NOACs are associated with a reduced incidence of thromboembolic events and major bleeding as compared with warfarin. Thus, NOACs may be considered a preferred option for this patient population., (Copyright © 2021. Published by Elsevier Inc.)

Soil temperatures play an important role in determining the distribution and function of organisms. However, soil temperature is decoupled from air temperature and varies widely in space. Characterizing and predicting soil temperature requires large and expensive networks of data loggers. We developed an open-source soil temperature data logger and created online resources to ensure our design was accessible. We tested data loggers constructed by students, with little prior electronics experience, in the lab, and in the field in Alaska. The do-it-yourself (DIY) data logger was comparably accurate to a commercial system with a mean absolute error of 2% from -20-0 °C and 1% from 0-20 °C. They captured accurate soil temperature data and performed reliably in the field with less than 10% failing in the first year of deployment. The DIY loggers were ~1.7-7 times less expensive than commercial systems. This work has the potential to increase the spatial resolution of soil temperature monitoring and serve as a powerful educational tool. The DIY soil temperature data logger will reduce data collection costs and improve our understanding of species distributions and ecological processes. It also provides an educational resource to enhance STEM, accessibility, inclusivity, and engagement.

Recent unprecedented fires in the Arctic during the past two decades have indicated a pressing need to understand the long-term ecological impacts of fire in this biome. Anecdotal evidence suggests that tundra fires can induce regime shifts that change tussock tundra to more shrub-dominated ecosystems. However, the ecological mechanisms regulating these shifts are poorly understood, but are hypothesized to involve changes to nutrient availability in this nutrient limited system. Here we conducted a 4-year two-factorial (control: C, nitrogen along: N + , phosphorus alone: P + , nitrogen and phosphorus combined: NP + ) fertilization experiment in both unburned and burned tundra to test this hypothesis after a decade of post-fire recovery. A decade after fire, the burned site exhibited an increase in soil nitrogen and phosphorus availability and a transition toward taller, more productive, and more deciduous vegetation. This shift in vegetation structure, composition, and function was induced at the unburned site through the addition of both NP + and the alleviation of their co-limitation. Both burned and unburned tundra responded similarly to fertilizer treatments by increasing leaf area index, greenness, and canopy height in NP + treatments, and exhibited no significant response in individual N + or P + treatments. These results point to a greater need to understand coupled carbon, nitrogen, and phosphorus cycles in this system, and suggest that post-fire regime shifts are regulated by the alleviation of nitrogen and phosphorus co-limitation in Arctic tundra., (© 2021 John Wiley & Sons Ltd.)

Background: Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the composite of heart failure (HF) hospitalizations or cardiovascular mortality among patients with HF. However, the efficacy of SGLT2 inhibitors in secondary endpoints of randomized trials and in subgroups of HF patients is not well known., Methods: We performed a systematic review and meta-analysis of placebo-controlled, randomized trials of SGLT2 inhibitors in patients with HF. PubMed, Embase, and Cochrane databases were searched for trials published up to January 21, 2021. Data were extracted from published reports and quality assessment was performed per Cochrane recommendations. Hazard ratios (HRs) with 95% CI were pooled across trials. The primary endpoints of interest were all-cause and cardiovascular mortality., Results: Out of 3969 database results, 15 randomized trials and 20,241 patients were included; 10,594 (52·3%) received SGLT2 inhibitors. All-cause mortality (HR 0·86; 95% CI 0·79-0·94; p  = 0·0007; I 2 =0%) and cardiovascular mortality (HR 0·86; 95% CI 0·78-0·96; p  = 0·006; I 2 =0%) were significantly lower in patients treated with SGLT2 inhibitors compared with placebo. The composite of cardiovascular mortality, HF hospitalizations, or urgent visits for HF was significantly reduced with SGLT2 inhibitors in all the following subgroups: male, female, age < 65, age ≥ 65, race - Black and White, estimated glomerular filtration rate (eGFR) <60, eGFR ≥60, New York Heart Association (NYHA) class II, NYHA ≥III, and HF with preserved ejection fraction., Interpretation: In patients with HF, SGLT2 inhibitors significantly reduce all-cause and cardiovascular mortality compared with placebo. In addition, the composite of cardiovascular mortality or HF hospitalizations/urgent visits is reduced with SGLT2 inhibitors across subgroups of sex, age, race, eGFR, HF functional class, and ejection fraction., Competing Interests: Dr. Bhatt reports grants from Amarin, grants from AstraZeneca, grants from Bristol-Myers Squibb, grants from Eisai, grants from Ethicon, grants from Medtronic, grants from sanofi aventis, grants from The Medicines Company, other from FlowCo, grants and other from PLx Pharma, other from Takeda, personal fees from Duke Clinical Research Institute, personal fees from Mayo Clinic, personal fees from Population Health Research Institute, personal fees, non-financial support and other from American College of Cardiology, personal fees from Belvoir Publications, personal fees from Slack Publications, personal fees from WebMD, personal fees from Elsevier, other from Medscape Cardiology, other from Regado Biosciences, other from Boston VA Research Institute, personal fees and non-financial support from Society of Cardiovascular Patient Care, non-financial support from American Heart Association, personal fees from HMP Global, grants from Roche, personal fees from Harvard Clinical Research Institute (now Baim Institute for Clinical Research), other from Clinical Cardiology, personal fees from Journal of the American College of Cardiology, other from VA, grants from Pfizer, grants from Forest Laboratories/AstraZeneca, grants from Ischemix, other from St. Jude Medical (now Abbott), other from Biotronik, grants and other from Cardax, other from Boston Scientific, grants from Amgen, grants from Lilly, grants from Chiesi, grants from Ironwood, personal fees from Cleveland Clinic, personal fees from Mount Sinai School of Medicine, other from Merck, grants from Abbott, grants from Regeneron, other from Svelte, grants and other from PhaseBio, grants from Idorsia, grants from Synaptic, personal fees from TobeSoft, grants, personal fees and other from Boehringer Ingelheim, personal fees from Bayer, grants and other from Novo Nordisk, grants from Fractyl, personal fees from Medtelligence/ReachMD, personal fees from CSL Behring, other from Cereno Scientific, grants from Afimmune, personal fees from Ferring Pharmaceuticals, other from CSI, grants from Lexicon, personal fees from MJH Life Sciences, personal fees from Level Ex, personal fees from Contego Medical, personal fees from CellProthera, personal fees from K2P, personal fees from Canadian Medical and Surgical Knowledge Translation Research Group, grants and other from MyoKardia/BMS, grants from Owkin, grants from HLS Therapeutics, grants from Janssen, outside the submitted work. All other authors have no disclosures., (© 2021 The Author(s).)

Climate change is creating widespread ecosystem disturbance across the permafrost zone, including a rapid increase in the extent and severity of tundra wildfire. The expansion of this previously rare disturbance has unknown consequences for lateral nutrient flux from terrestrial to aquatic environments. Lateral loss of nutrients could reduce carbon uptake and slow recovery of already nutrient-limited tundra ecosystems. To investigate the effects of tundra wildfire on lateral nutrient export, we analyzed water chemistry in and around the 10-year-old  Anaktuvuk River fire scar in northern Alaska. We collected water samples from 21 burned and 21 unburned watersheds during snowmelt, at peak growing season, and after plant senescence in 2017 and 2018. After a decade of ecosystem recovery, aboveground biomass had recovered in burned watersheds, but overall carbon and nitrogen remained ~20% lower, and the active layer remained ~10% deeper. Despite lower organic matter stocks, dissolved organic nutrients were substantially elevated in burned watersheds, with higher flow-weighted concentrations of organic carbon (25% higher), organic nitrogen (59% higher), organic phosphorus (65% higher), and organic sulfur (47% higher). Geochemical proxies indicated greater interaction with mineral soils in watersheds with surface subsidence, but optical analysis and isotopes suggested that recent plant growth, not mineral soil, was the main source of organic nutrients in burned watersheds. Burned and unburned watersheds had similar δ 15 N-NO 3 - , indicating that exported nitrogen was of preburn origin (i.e., not recently fixed). Lateral nitrogen flux from burned watersheds was 2- to 10-fold higher than rates of background nitrogen fixation and atmospheric deposition estimated in this area. These findings indicate that wildfire in Arctic tundra can destabilize nitrogen, phosphorus, and sulfur previously stored in permafrost via plant uptake and leaching. This plant-mediated nutrient loss could exacerbate terrestrial nutrient limitation after disturbance or serve as an important nutrient release mechanism during succession., (© 2021 John Wiley & Sons Ltd.)

Introduction  Tinnitus is a disorder that affects 10 to 15% of de world's population. Sound therapy performed through hearing aids (HAs) with integrated sound generator (SG) is one of the forms of tinnitus treatment. Objective  To analyze the effectiveness of four masking noises in relieving tinnitus in individuals with mild and moderate bilateral sensorineural hearing loss and their influence in speech perception. Methods  The participants were 35 individuals with tinnitus and mild and moderate bilateral sensorineural hearing loss, divided into four groups. All groups underwent HA and SG adaptation, being regulated in the combined mode (HA and SG). In group 1 (G1), the white noise stimulus was applied, in group 2 (G2), pink noise was applied, in group 3 (G3), speech noise, and in group 4 (G4), the high tone was applied. All patients were subjected to the following procedures: audiological diagnosis, acuphenometry, tinnitus handicap inventory (THI), visual analogue scale (VAS), and hearing in noise test (HINT). The procedures were performed prior to and after hearing intervention, and after 3 months of use of HA and SG. Results  All groups presented a statistically significant difference for the THI, VAS, and HINT pre and postintervention. In the case of the HINT, only pink noise presented a significant difference. However, in the comparation among groups there was no significant difference. Conclusion  The present study made it possible to conclude that the four noises were equally effective in relieving tinnitus, with no statistically significant differences between the analyzed groups., Competing Interests: Conflict of Interests The authors declare that there is no conflict of interests., (Fundação Otorrinolaringologia. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

We tested whether post-fire seedling establishment of common boreal tree and expanding shrub species at treeline and in Arctic tundra is facilitated by co-migration of boreal forest mycorrhizal fungi. Wildfires are anticipated to facilitate biome shifts at the forest-tundra ecotone by improving seedbed conditions for recruiting boreal species; at the same time fire alters the composition and availability of mycorrhizal fungi critical to seedling performance. To determine the role of root-associated fungi (RAF) in post-fire seedling recruitment and future biome shifts, we outplanted four dominant boreal tree and shrub species inoculated with one of three treatments at treeline and in tundra: burned boreal forest, unburned boreal forest, or a control treatment of sterilized inoculum. We compared survivorship, growth, and physiological performance of the seedlings in relation to mycorrhizal inoculum treatment and among host species, characterized the RAF communities based on ITS-rDNA sequencing of individual root tips sampled from surviving seedlings, and tested for correlations between RAF composition and the inoculation treatments, host species, and duration of the experiment. We explored correlations between RAF composition and seedling metrics. Both live and sterile autoclaved inoculation treatments had similar effects on seedling survivorship and growth for all species. RAF composition did not vary by treatment, suggesting that most colonization was due to local fungi. However, seedling traits and growth were correlated with RAF species composition, colonization, and the relative abundance of specific RAF taxa. Picea sp. performance in particular showed strong co-variation with RAF metrics. Our results suggest that mycorrhizal co-migration is not a primary limiting factor to boreal seedling recruitment because the experimental provision of inoculum did not affect seedling recruitment; yet, RAF did influence seedling performance, particularly resident RAF at treeline and in tundra, suggesting that mycorrhizal fungi are important to vegetation processes at the treeline-tundra ecotone., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Tinnitus is present in a large part of chronic health complaints, and it is considered a public health problem injurious to the individual's quality of life. Considering the increase of the world population associated with an increase of life expectancy, tinnitus remains a cause for medical concern, since during aging the occurrence of auditory impairments due to the deterioration of the peripheral auditory structures and central impairs the quality of life., Objective: The aim of the present study was to analyze the applicability of real ear measurements for audiological intervention of tinnitus through specific evaluation, selection, verification and validation of the hearing aids combined with the sound generator., Methods: Forty individuals of both genders with hearing loss and tinnitus complaints were deemed eligible to compose the sample. They were enrolled according to clinical symptoms and submitted to the following procedures: anamnesis and previous complaint history, high frequency audiometry, immittanciometry and acuphenometry with the research of psychoacoustic thresholds of pitch, loudness and minimum masking threshold, sound generator, in addition to the application of the Tinnitus Handicap Inventory and Visual Analog Scale tools. The entire sample was adapted with Siemens hearing aids and a sound generator, participated in a counseling session with support of digital material and evaluated in two situations: Initial Assessment (before the hearing aids and sound generator adaptation) and Final Assessment (6 months, after adaptation). The statistical analyzes were descriptive and inferential, adopted a significance level of 5% and the T-Paired Test and the Spearman Correlation test were performed., Results: The results showed that there was a benefit with the use of hearing aids combined with a sound generator from the statistically significant values and strong correlations between the sound generator verification data regarding acuphenometry and the nuisance/severity questionnaires. Regarding the verification of the sound generator, it is important to highlight that the entire sample selected the effective acoustic stimulation based on the comfort levels, which was proved in the present study to be a sufficient intensity for positive prognosis, whereas the users' noises were found below the psychoacoustic thresholds of acuphenometry., Conclusion: The present study concluded that the audiological intervention with any level of sound stimulus is enough to obtain a positive prognosis in the medium term. Data that specifies that the verification of sound generator was effective at the real ear measurements are important in the evaluation and intervention of the complaint. In addition, it points out that the greater the tinnitus perception, the greater its severity, and the greater the nuisance, the higher the psychoacoustics thresholds of frequency and the minimum threshold of masking., (Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.)

The aim of this study was to characterize the central effects of the Hyptis martiusii leaf essential oil (OEHM) and 1,8-cineole (eucalyptol) using behavioral animal models. Gas chromatography coupled to mass spectrometry (GC/MS) was used to characterize the chemical compounds present in the OEHM. For the behavioral tests, female Swiss mice treated with the OEHM (25, 50, 100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) were used and subjected to the following tests: open field, elevated cross maze, rotarod, sodium pentobarbital- or ethyl ether-induced sleep time, pentylenetetrazol-induced convulsions, haloperidol-induced catalepsy, and ketamine-induced hyperkinesia. GC/MS analysis identified 20 constituents with the majority of them being monoterpenes and sesquiterpenes, with eucalyptol (1,8-cineol), the major sample compound (25.93%), standing out. The results showed the OEHM (25, 50 100 and 200 mg/kg, i.p.) and its major compound (50 mg/kg, i.p.) reduced animal motility in the open field test, increased pentobarbital- and ethyl ether-induced sleep time, as well as death latency in the pentylenetetrazole-induced convulsion model. However, the tested compounds were devoid of anxiolytic-like and myorelaxant activity. In addition, the OEHM (100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) potentiated haloperidol-induced catalepsy and reduced ketamine-induced hyperkinesia. Taken together, the results suggest the OEHM has important hypnotic-sedative and antipsychotic-like effects, which appear to be due to the monoterpene 1,8-cineole, the major compound identified in the essential oil., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The response of vegetation to climate change has implications for the carbon cycle and global climate. It is frequently assumed that a species responds uniformly across its range to climate change. However, ecotypes - locally adapted populations within a species - display differences in traits that may affect their gross primary productivity (GPP) and response to climate change. To determine if ecotypes are important for understanding the response of ecosystem productivity to climate we measured and modeled growing season GPP in reciprocally transplanted and experimentally warmed ecotypes of the abundant Arctic sedge Eriophorum vaginatum. Transplanted northern ecotypes displayed home-site advantage in GPP that was associated with differences in leaf area index. Southern ecotypes exhibited a greater response in GPP when transplanted. The results demonstrate that ecotypic differentiation can impact the morphology and function of vegetation with implications for carbon cycling. Moreover they suggest that ecotypic control of GPP may limit the response of ecosystem productivity to climate change. This investigation shows that ecotypes play a substantial role in determining GPP and its response to climate. These results have implications for understanding annual to decadal carbon cycling where ecotypes could influence ecosystem function and vegetation feedbacks to climate change., (© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust.)

We performed phylogeographic and genetic structure analyses of Neothraupis fasciata joined with species distribution modelling to evaluate whether: (1) the distribution of genetic variability shows a pattern expected by the isolation-by-distance model; (2) the influence of the Pleistocene climate changes on species distribution; and (3) climate/climatic stability (hypothesis of climatic stability) as a predictor of population genetic diversity. Based on two molecular datasets (ND2 and FIB-5), the isolation-by-distance hypothesis was not supported. The mitochondrial haplotype network indicated the existence of historically isolated populations at the southern range of the species distribution, and recent population expansion was identified by both neutrality tests and extended Bayesian skyline plot analysis. Thus, the climatic changes during the Pleistocene might have promoted the reconnection of the partially isolated southern populations, which may have persisted in the plateaus during the cycles of savanna contractions. Subsequently, this species (re)colonized northern areas of the species present distribution, following the continuous vegetation on the São Francisco and Central plateaus about 60 kyr, and also reached the Amazonian savannas likely via the central corridor. Thus, our results indicated that the intrinsic relationship between the relief heterogeneity (plateaus and depressions) and the climatic fluctuations, mainly in the Pleistocene, promoted population reconnection and demographic expansion of N. fasciata., Competing Interests: The authors have declared that no competing interests exist.

Solar-induced chlorophyll fluorescence (SIF) has been increasingly used as a proxy for terrestrial gross primary productivity (GPP). Previous work mainly evaluated the relationship between satellite-observed SIF and gridded GPP products both based on coarse spatial resolutions. Finer resolution SIF (1.3 km × 2.25 km) measured from the Orbiting Carbon Observatory-2 (OCO-2) provides the first opportunity to examine the SIF-GPP relationship at the ecosystem scale using flux tower GPP data. However, it remains unclear how strong the relationship is for each biome and whether a robust, universal relationship exists across a variety of biomes. Here we conducted the first global analysis of the relationship between OCO-2 SIF and tower GPP for a total of 64 flux sites across the globe encompassing eight major biomes. OCO-2 SIF showed strong correlations with tower GPP at both midday and daily timescales, with the strongest relationship observed for daily SIF at the 757 nm (R 2  = 0.72, p < 0.0001). Strong linear relationships between SIF and GPP were consistently found for all biomes (R 2  = 0.57-0.79, p < 0.0001) except evergreen broadleaf forests (R 2  = 0.16, p < 0.05) at the daily timescale. A higher slope was found for C 4 grasslands and croplands than for C 3 ecosystems. The generally consistent slope of the relationship among biomes suggests a nearly universal rather than biome-specific SIF-GPP relationship, and this finding is an important distinction and simplification compared to previous results. SIF was mainly driven by absorbed photosynthetically active radiation and was also influenced by environmental stresses (temperature and water stresses) that determine photosynthetic light use efficiency. OCO-2 SIF generally had a better performance for predicting GPP than satellite-derived vegetation indices and a light use efficiency model. The universal SIF-GPP relationship can potentially lead to more accurate GPP estimates regionally or globally. Our findings revealed the remarkable ability of finer resolution SIF observations from OCO-2 and other new or future missions (e.g., TROPOMI, FLEX) for estimating terrestrial photosynthesis across a wide variety of biomes and identified their potential and limitations for ecosystem functioning and carbon cycle studies., (© 2018 John Wiley & Sons Ltd.)

At least four mitogenome arrangements occur in Passeriformes and differences among them are derived from an initial tandem duplication involving a segment containing the control region (CR), followed by loss or reduction of some parts of this segment. However, it is still unclear how often duplication events have occurred in this bird order. In this study, the mitogenomes from two species of Neotropical passerines (Sicalis olivascens and Lepidocolaptes angustirostris) with different gene arrangements were first determined. We also estimated how often duplication events occurred in Passeriformes and if the two CR copies demonstrate a pattern of concerted evolution in Sylvioidea. One tissue sample for each species was used to obtain the mitogenomes as a byproduct using next generation sequencing. The evolutionary history of mitogenome rearrangements was reconstructed mapping these characters onto a mitogenome Bayesian phylogenetic tree of Passeriformes. Finally, we performed a Bayesian analysis for both CRs from some Sylvioidea species in order to evaluate the evolutionary process involving these two copies. Both mitogenomes described comprise 2 rRNAs, 22 tRNAs, 13 protein-codon genes and the CR. However, S. olivascens has 16,768 bp showing the ancestral avian arrangement, while L. angustirostris has 16,973 bp and the remnant CR2 arrangement. Both species showed the expected gene order compared to their closest relatives. The ancestral state reconstruction suggesting at least six independent duplication events followed by partial deletions or loss of one copy in some lineages. Our results also provide evidence that both CRs in some Sylvioidea species seem to be maintained in an apparently functional state, perhaps by concerted evolution, and that this mechanism may be important for the evolution of the bird mitogenome.

Introduction: The relations between the tinnitus and the hearing loss are due to the sensory deprivation caused by hearing loss, since this is followed by the functional and structural alteration of the auditory system as a whole. The cochlear lesions are accompanied by a reduction in the activity of the cochlear nerve, and the neural activity keeps increased in mainly all the central auditory nervous system to compensate this deficit., Objective: This study aimed to verify the effectiveness of the sound generator (SG) associated with the counseling in the treatment of the tinnitus in individuals with and without hearing loss regarding the improvement of the nuisance through Tinnitus Handicap Inventory (THI) and Visual Analogue Scale (VAS)., Methods: The sample consisted of 30 individuals of both genders divided into two groups: Group 1 (G1) was comprised of 15 individuals with tinnitus and normal hearing, adapted to SG; Group 2 (G2) was comprised of 15 individuals with complaints of hearing acuity and tinnitus, adapted with SG and an individual hearing aid device (HA). Both groups underwent the following procedures: anamnesis and history of complaint, high frequency audiometry (HFA), imitanciometry, acuphenometry with the survey of psychoacoustic pitch and loudness thresholds and application of the tools THI and VAS. All of them were adapted with HA and Siemens SG and participated in a session of counseling. The individuals were assessed in three situations: initial assessment (before the adaptation of the HA and SG), monitoring and final assessment (6 months after adaptation)., Results: The comparison of the tinnitus nuisance and handicap in the three stages of assessment showed a significant improvement for both groups., Conclusion: The use of the SG was similarly effective in the treatment of the tinnitus in individuals with and without hearing loss, causing an improvement of the nuisance and handicap., (Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.)

To investigate the underlying mechanisms that control long-term recovery of tundra carbon (C) and nutrients after fire, we employed the Multiple Element Limitation (MEL) model to simulate 200-yr post-fire changes in the biogeochemistry of three sites along a burn severity gradient in response to increases in air temperature, CO 2 concentration, nitrogen (N) deposition, and phosphorus (P) weathering rates. The simulations were conducted for severely burned, moderately burned, and unburned arctic tundra. Our simulations indicated that recovery of C balance after fire was mainly determined by the internal redistribution of nutrients among ecosystem components (controlled by air temperature), rather than the supply of nutrients from external sources (e.g., nitrogen deposition and fixation, phosphorus weathering). Increases in air temperature and atmospheric CO 2 concentration resulted in (1) a net transfer of nutrient from soil organic matter to vegetation and (2) higher C : nutrient ratios in vegetation and soil organic matter. These changes led to gains in vegetation biomass C but net losses in soil organic C stocks. Under a warming climate, nutrients lost in wildfire were difficult to recover because the warming-induced acceleration in nutrient cycles caused further net nutrient loss from the system through leaching. In both burned and unburned tundra, the warming-caused acceleration in nutrient cycles and increases in ecosystem C stocks were eventually constrained by increases in soil C : nutrient ratios, which increased microbial retention of plant-available nutrients in the soil. Accelerated nutrient turnover, loss of C, and increasing soil temperatures will likely result in vegetation changes, which further regulate the long-term biogeochemical succession. Our analysis should help in the assessment of tundra C budgets and of the recovery of biogeochemical function following fire, which is in turn necessary for the maintenance of wildlife habitat and tundra vegetation., (© 2016 by the Ecological Society of America.)

Mercury is potent toxicant element, but its toxicity can be reduced by forming a complex with selenium for safe excretion. Considering the impact of mercury exposure in the Amazon region and the possible interaction between these two elements, we aimed to assess the effects of Pro198Leu polymorphism to GPX1 and GSTM1 deletion, on mercury levels in a population from Porto Velho, an urban locality in the Brazilian Amazon region. Two hundred women from the capital city of Rondônia state were recruited for this study with 149 deemed suitable to participate. We assessed dietary intake using 24-hour recall. Selenium levels in plasma and erythrocytes were measured using hydride generation quartz tube atomic absorption spectroscopy and total hair mercury using cold vapor atomic absorption spectrometry. Oxidative stress parameters (GPx activity, oxygen radical absorbency capacity [ORAC] and malondialdehyde [MDA]) were also analyzed. All participants were genotyped for Pro198Leu polymorphism and GSTM1 deletion. We observed that this population presented high prevalence of selenium deficiency, and also low levels of mercury, likely due to food habits that did not include selenium-rich food sources or significant consumption of fish (mercury biomagnifiers) regularly. Univariate statistical analysis showed that Pro198Leu and GSTM1 genotypes did not affect selenium and mercury levels in this population. Pro198Leu polymorphism and GSTM1 deletion had no effect on mercury levels in mildly exposed people, suggesting these genetic variants impact mercury levels only in highly exposed populations., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Fire frequency has dramatically increased in the tundra of northern Alaska, USA, which has major implications for the carbon budget of the region and the functioning of these ecosystems, which support important wildlife species. We investigated the postfire succession of plant and soil carbon (C), nitrogen (N), and phosphorus (P) fluxes and stocks along a burn severity gradient in the 2007 Anaktuvuk River fire scar in northern Alaska. Modeling results indicated that the early regrowth of postfire tundra vegetation was limited primarily by its canopy photosynthetic potential, rather than nutrient availability, because of the initially low leaf area and relatively high inorganic N and P concentrations in soil. Our simulations indicated that the postfire recovery of tundra vegetation was sustained predominantly by the uptake of residual inorganic N (i.e., in the remaining ash), and the redistribution of N and P from soil organic matter to vegetation. Although residual nutrients in ash were higher in the severe burn than the moderate burn, the moderate burn recovered faster because of the higher remaining biomass and consequent photosynthetic potential. Residual nutrients in ash allowed both burn sites to recover and exceed the unburned site in both aboveground biomass and production five years after the fire. The investigation of interactions among postfire C, N, and P cycles has contributed to a mechanistic understanding of the response of tundra ecosystems to fire disturbance. Our study provided insight on how the trajectory of recovery of tundra from wildfire is regulated during early succession.

Objective: To verify the receiver in the ear and receiver in the aid adaptations by measuring in situ the speech perception and users' level of satisfaction., Methods: The study was approved by the research ethics committee (Process: 027/2011). Twenty subjects older than 18 years with audiological diagnosis of mild and moderate bilateral descending sensorineural hearing loss were evaluated. The subjects were divided into two groups, where G1 (group 1) was fitted with open-fit hearing aids with the built-in receiver unit (receiver in the ear) and G2 (group 2) was fitted with open-fit hearing aids with RITE. A probe microphone measurement was performed to check the gain and output provided by the amplification and for assessment of speech perception with Hearing in Noise Test with and without hearing aids. After a period of six weeks of use without interruption, the subjects returned for follow-up and answered the Satisfaction with Amplification in Daily Life questionnaire, and were again subjected to Hearing in Noise Test., Results: Both groups presented better test results for speech recognition in the presence of noise., Conclusion: Groups 1 and 2 were satisfied with the use of hearing aids and improved speech recognition in silent and noisy situations with hearing aids., (Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.)

Coalescent theory provides powerful models for population genetic inference and is now increasingly important in estimates of divergence times and speciation research. We use molecular data and methods based on coalescent theory to investigate whether genetic evidence supports the hypothesis of A. pretrei and A. tucumana as separate species and whether genetic data allow us to assess which allopatric model seems to better explain the diversification process in these taxa. We sampled 13 A. tucumana from two provinces in northern Argentina and 28 A. pretrei from nine localities of Rio Grande do Sul, Brazil. A 491 bp segment of the mitochondrial gene cytochrome c oxidase I was evaluated using the haplotype network and phylogenetic methods. The divergence time and other demographic quantities were estimated using the isolation and migration model based on coalescent theory. The network and phylogenetic reconstructions showed similar results, supporting reciprocal monophyly for these two taxa. The divergence time of lineage separation was estimated to be approximately 1.3 million years ago, which corresponds to the lower Pleistocene. Our results enforce the current taxonomic status for these two Amazon species. They also support that A. pretrei and A. tucumana diverged with little or no gene flow approximately 1.3 million years ago, most likely after the establishment of a small population in the Southern Yungas forest by dispersion of a few founders from the A. pretrei ancestral population. This process may have been favored by habitat corridors formed in hot and humid periods of the Quaternary. Considering that these two species are considered threatened, the results were evaluated for their implications for the conservation of these two species.

Most North American forests are at some stage of post-disturbance regrowth, subject to a changing climate, and exhibit growth and mortality patterns that may not be closely coupled to annual environmental conditions. Distinguishing the possibly interacting effects of these processes is necessary to put short-term studies in a longer term context, and particularly important for the carbon-dense, fire-prone boreal forest. The goals of this study were to combine dendrochronological sampling, inventory records, and machine-learning algorithms to understand how tree growth and death have changed at one highly studied site (Northern Old Black Spruce, NOBS) in the central Canadian boreal forest. Over the 1999-2012 inventory period, mean tree diameter increased even as stand density and basal area declined significantly. Tree mortality averaged 1.4 ± 0.6% yr-(1), with most mortality occurring in medium-sized trees; new recruitment was minimal. There have been at least two, and probably three, significant influxes of new trees since stand initiation, but none in recent decades. A combined tree ring chronology constructed from sampling in 2001, 2004, and 2012 showed several periods of extreme growth depression, with increased mortality lagging depressed growth by ~5 years. Higher minimum and maximum air temperatures exerted a negative influence on tree growth, while precipitation and climate moisture index had a positive effect; both current- and previous-year data exerted significant effects. Models based on these variables explained 23-44% of the ring-width variability. We suggest that past climate extremes led to significant mortality still visible in the current forest structure, with decadal dynamics superimposed on slower patterns of fire and succession. These results have significant implications for our understanding of previous work at NOBS, the carbon sequestration capability of old-growth stands in a disturbance-prone landscape, and the sustainable management of regional forests in a changing climate.

The rapidly warming temperatures in high-latitude and alpine regions have the potential to alter the phenology of Arctic and alpine plants, affecting processes ranging from food webs to ecosystem trace gas fluxes. The International Tundra Experiment (ITEX) was initiated in 1990 to evaluate the effects of expected rapid changes in temperature on tundra plant phenology, growth and community changes using experimental warming. Here, we used the ITEX control data to test the phenological responses to background temperature variation across sites spanning latitudinal and moisture gradients. The dataset overall did not show an advance in phenology; instead, temperature variability during the years sampled and an absence of warming at some sites resulted in mixed responses. Phenological transitions of high Arctic plants clearly occurred at lower heat sum thresholds than those of low Arctic and alpine plants. However, sensitivity to temperature change was similar among plants from the different climate zones. Plants of different communities and growth forms differed for some phenological responses. Heat sums associated with flowering and greening appear to have increased over time. These results point to a complex suite of changes in plant communities and ecosystem function in high latitudes and elevations as the climate warms.

Introduction: Hearing loss (HL) is defined as the complete or partial loss of hearing ability., Aims: To characterize (1) the degree of satisfaction among adult and elderly hearing aid (HA) users who were treated by a public hearing health service and (2) the relationship between satisfaction and the variables of gender, age, degree of HL, and type of HA., Method: The clinical and experimental study included the administration of the Satisfaction with Amplification in Daily Life (SADL) questionnaire to 110 patients who had used HAs for more than 3 months and were 18 years of age or older., Results: Test patients were sex-balanced (48% were women) and had a mean age of 67 years. A relatively high incidence of sensorineural moderate HL was detected in the study patients (66%) and device B was the most commonly used HA type (48%). No significant differences were evident between HA satisfaction and sex. The importance placed on services/costs and personal image varied between age groups. Correlation was evident at all levels between user satisfaction and amplification. Decreased satisfaction was observed in individuals with severe and/or profound HL. The type of HA used yielded statistically significant differences in the positive effects referring., Conclusion: No correlations were evident between the different factors proposed. HA users exhibited high levels of satisfaction in all SADL areas.

The present study aimed to investigate the association of endothelial nitric oxide synthase (eNOS) gene polymorphisms with primary open angle glaucoma (POAG). We conducted a case-control study that included 90 patients with POAG and 127 healthy controls whose blood samples were genotyped for the functional polymorphisms T-786C and Glu298Asp of the eNOS gene by Taqman fluorescent allelic discrimination assay. The T-786C polymorphism was significantly associated as a risk factor for POAG among women (OR: 2.28; 95% CI: 1.11 to 4.70, p=0.024) and marginally associated to the risk of POAG in the patients ≥52 years of age at diagnosis (OR: 2.11; 95% CI: 0.98 to 4.55, p=0,055). However, these results was not confirmed after adjustments for gender, age, self-declared skin color, tobacco smoking and eNOS genotypes by multivariate logistic regression model (OR: 2.08; 95% CI: 0.87 to 5.01, p=0.101 and OR: 2.20; 95% CI: 0.95 to 5.12, p=0.067, respectively). The haplotype CG of T-786C and Glu298Asp showed a borderline association with risk of POAG in the overall analysis (OR: 1.76; 95% CI: 0.98 to 3.14, p=0.055) and among women (OR: 2.02; 95% CI: 0.98 to 4.16, p=0.052). Furthermore, the CG haplotype was significantly associated with the development of POAG for the age at diagnosis group ≥52 years (OR: 3.48; 95% CI: 1.54 to 7.84, p=0.002).We suggested that haplotypes of the polymorphisms T-786C and Glu298Asp of eNOS may interact with gender and age in modulating the risk of POAG., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: Large amounts of reactive oxygen species are produced in hemodialysis (HD) patients, and, at higher concentrations, reactive oxygen species are thought to be involved in the pathogenesis of cardiovascular disease. It has been proposed that selenium (Se) may exert an antiatherogenic influence by reducing oxidative stress. The richest known food source of Se is the Brazil nut (Bertholletia excelsa, family Lecythidaceae), found in the Amazon region., Objective: The objective of this work was to determine if Se plasma levels in HD patients submitted to a program of supplementation during 3 months with 1 Brazil nut by day could be sustained after 12 months., Methods: A total of 21 HD patients (54.2 ± 15.2 years old; average time on dialysis, 82.3 ± 51.6 months; body mass index, 24.4 ± 3.8 kg/m(2)) from the RenalCor Clinic in Rio de Janeiro, Brazil, were followed up 12 months after the supplementation study ended. The Se plasma levels were determined by atomic absorption spectrophotometry with hydride generation., Results: The Se Plasma levels (17.3 ± 19.9 μg/L) were below the normal range (60 to 120 μg/L) before nut supplementation, and after 3 months of supplementation, the levels increased to 106.8 ± 50.3 μg/L (P < .0001). Twelve months after supplementation, the plasma Se levels decreased to 31.9 ± 14.8 μg/L (P < .0001)., Conclusions: The data showed that these patients were Se deficient and that the consumption of Brazil nut was effective to increase the Se parameters of nutritional status. Se levels 12 months after the supplementation period were not as low as presupplementation levels but yet significantly lower, and we needed to motivate patients to adopt different dietary intake patterns., (Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

The δ¹⁸O and δD composition of water pools (leaf, root, standing water and soil water) and fluxes [transpiration (T), evaporation (E)] were used to understand ecohydrological processes in a managed Typha latifolia L. freshwater marsh. We observed isotopic steady-state T and deep rooting in Typha. The isotopic mass balance of marsh standing water showed that E accounted for 3% of the total water loss, T accounted for 17% and subsurface drainage (D) accounted for the majority (80%). There was a vertical gradient in water vapour content and isotopic composition within and above the canopy sufficient for constructing an isotopic mass balance of water vapour during some sampling periods. During these periods, the proportion of T in evapotranspiration (T/ET) was between 56 ± 17% and 96 ± 67%, and the estimated error was relatively high (>37%) because of non-local, background sources in vapour. Independent estimates of T/ET using eddy covariance measurements yielded similar mean values during the Typha growing season. The various T/ET estimates agreed that T was the dominant source of marsh vapour loss in the growing season. The isotopic mass balance of water vapour yielded reasonable results, but the mass balance of standing water provided more definitive estimates of water losses., (© 2011 Blackwell Publishing Ltd.)

Burned landscapes present several challenges to quantifying landscape carbon balance. Fire scars are composed of a mosaic of patches that differ in burn severity, which may influence postfire carbon budgets through damage to vegetation and carbon stocks. We deployed three eddy covariance towers along a burn severity gradient (i.e., severely burned, moderately burned, and unburned tundra) to monitor postfire net ecosystem exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar in Alaska, USA, during the summer of 2008. Remote sensing data from the MODerate resolution Imaging Spectroradiometer (MODIS) was used to assess the spatial representativeness of the tower sites and parameterize a NEE model that was used to scale tower measurements to the landscape. The tower sites had similar vegetation and reflectance properties prior to the Anaktuvuk River fire and represented the range of surface conditions observed within the fire scar during the 2008 summer. Burn severity influenced a variety of surface properties, including residual organic matter, plant mortality, and vegetation recovery, which in turn determined postfire NEE. Carbon sequestration decreased with increased burn severity and was largely controlled by decreases in canopy photosynthesis. The MODIS two-band enhanced vegetation index (EVI2) monitored the seasonal course of surface greenness and explained 86% of the variability in NEE across the burn severity gradient. We demonstrate that understanding the relationship between burn severity, surface reflectance, and NEE is critical for estimating the overall postfire carbon balance of the Anaktuvuk River fire scar.