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Introduction: Online question-and-answer (Q&A) platforms are frequently replete with extensive human resource support. This study proposes a novel methodology of a customized large language model (LLM) called Chaotic LLM-based Educational Q&A System (CHAQS) to navigate the complexities associated with intelligent Q&A systems for the educational sector. Methods: It uses an expansive dataset comprising over 383,000 educational data pairs, an intricate fine-tuning process encompassing p-tuning v2, low-rank adaptation (LRA), and strategies for parameter freezing at an open-source large language model ChatGLM as a baseline model. In addition, Fuzzy Logic is implemented to regulate parameters and the system's adaptability with the Lee Oscillator to refine the model's response variability and precision. Results: Experiment results showed a 5.12% improvement in precision score, an 11% increase in recall metric, and an 8% improvement in the F1 score as compared to other models. Discussion: These results suggest that the CHAQS methodology significantly enhances the performance of educational Q&A systems, demonstrating the effectiveness of combining advanced tuning techniques and fuzzy logic for improved model precision and adaptability.
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Classic Impella exchange interrupts flow when the old device is pulled into the aorta before advancing the new device across the aortic valve, threatening circulatory collapse and loss of left ventricular access. In "double barrel," uninterrupted Impella exchange, the new device is placed into the ventricle alongside the old, where flow is first transitioned completely. Of thirty-one consecutive patients undergoing this procedure, none experienced intraoperative cardiac arrest and 96.8% (30/31) had no new aortic insufficiency. One vascular complication ensued following known preoperative iliac injury. One patient suffered nonembolic stroke; another had subarachnoid hemorrhage. Fifty-five percent (17/31) of patients survived, with 22.6% (7/31) recovering, 25.8% (8/31) undergoing transplant, and 6.5% (2/31) transitioning to durable LVAD. Impella-only survival (83.3%, 10/12) was significantly higher than Impella-ECMO survival (36.8%, 7/19) (OR 14.46, 95% CI 1.74-119.93, p=0.01). We conclude "double barrel" technique is reliable in device-dependent cardiogenic shock patients, offering significant advantage and minimal risk.
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Purpose: To assess oral sedation success using midazolam and hydroxyzine with and without meperidine, and to assess the relationship between child temperament and sedation outcomes. Methods: This study recruited children between the ages of 36 and 95 months who were randomly assigned to receive dental treatment with an oral sedation regimen of midazolam (0.5 mg/kg) and hydroxyzine (1.0 mg/kg) with or without meperidine (1.5 mg/kg). Data were collected from the treatment log and electronic health records. Parents completed the Child Behavior Questionnaire Short Form (CBQ-SF) to assess temperament. Results: The study included 37 participants. The overall treatment success rate was 54 percent. There were no significant differences in sedation outcome with age, sex, insurance status, sedation regimen, isolation method or duration of procedure. Children with high pre-operative Frankl behavioral ratings were more likely to have a successful sedation outcome (P <0.01). Children who displayed high soothability experienced higher rates of success (P =0.04), which was more pronounced in the non-opioid group (P <0.01). Conclusion: The study showed low rates of success for a relatively small sample size. There was no difference in sedation success between the opioid group and non-opioid group. However, pre-procedure behavior and temperament characteristic of sooth- ability may warrant more exploration as predictors of sedation success.
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Anestesia Dentária , Sedação Consciente , Hidroxizina , Hipnóticos e Sedativos , Meperidina , Midazolam , Temperamento , Humanos , Feminino , Masculino , Pré-Escolar , Hidroxizina/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Sedação Consciente/métodos , Meperidina/uso terapêutico , Anestesia Dentária/métodos , Criança , Midazolam/uso terapêutico , Comportamento Infantil/efeitos dos fármacos , Resultado do Tratamento , Analgésicos Opioides/uso terapêutico , Inquéritos e Questionários , Assistência Odontológica para Crianças/métodosRESUMO
WormBase has been the major repository and knowledgebase of information about the genome and genetics of Caenorhabditis elegans and other nematodes of experimental interest for over 2 decades. We have 3 goals: to keep current with the fast-paced C. elegans research, to provide better integration with other resources, and to be sustainable. Here, we discuss the current state of WormBase as well as progress and plans for moving core WormBase infrastructure to the Alliance of Genome Resources (the Alliance). As an Alliance member, WormBase will continue to interact with the C. elegans community, develop new features as needed, and curate key information from the literature and large-scale projects.
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Caenorhabditis elegans , Caenorhabditis elegans/genética , Animais , Bases de Dados Genéticas , Genoma Helmíntico , Genômica/métodosRESUMO
Limited donor organ availability often necessitates mechanical circulatory support, and recently the Impella 5.5, as a bridge to heart transplant. Of 175 Impella 5.5-supported patients at our institution, 45 underwent transplantation in the largest series to date, for whom we analyzed outcomes. Two methods of complete device explant were evaluated: central Impella transection and removal via axillary graft. Median Impella days were 25 (16-41); median waitlist days were 21 (9-37). Eighty-nine percent (40/45) of patients had device placement via right axillary artery. Seventy-six percent (34/45) underwent central transection for device removal. Four patients (8.9%) required short-term venoarterial extracorporeal membranous oxygenation (VA ECMO) postoperatively for primary graft dysfunction (PGD). Two patients (4.4%) suffered postoperative stroke. Five patients (11.1%) required new RRT postoperatively. One patient (2.2%) returned to the operating room (OR) for axillary graft bleeding. A higher chance of procedural complications was found with the axillary removal technique (p = 0.014). Median intensive care unit (ICU) days, length of stay (LOS), and postoperative days to discharge were 46 (35-63), 59 (49-80), and 18 (15-24), respectively. Ninety-eight percent (44/45) survived to discharge. Thirty-day survival was 95.6% (43/45), with 1 year survival at 90.3% (28/31). Eighty-eight percent (37/42) remain without rejection. In our institutional experience, Impella 5.5 is a safe and reliable bridge to transplant.
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There was an error in our original publication [...].
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BACKGROUND: Accurate measurement of polyps size is crucial in predicting malignancy, planning relevant intervention strategies and surveillance schedules. Endoscopists' visual estimations can lack precision. This study builds on our prior research, with the aim to evaluate a recently developed quantitative method to measure the polyp size and location accurately during a simulated endoscopy session. METHODS: The quantitative method merges information about endoscopic positions obtained from an electromagnetic tracking sensor, with corresponding points on the images of the segmented polyp border. This yields real-scale 3D coordinates of the border of the polyp. By utilising the sensor, positions of any anatomical landmarks are attainable, enabling the estimation of a polyp's location relative to them. To verify the method's reliability and accuracy, simulated endoscopies were conducted in pig stomachs, where polyps were artificially created and assessed in a test-retest manner. The polyp measurements were subsequently compared against clipper measurements. RESULTS: The average size of the fifteen polyps evaluated was approximately 12 ± 4.3 mm, ranging from 5 to 20 mm. The test-retest reliability, measured by the Intraclass Correlation Coefficient (ICC) for polyp size estimation, demonstrated an absolute agreement of 0.991 (95% CI 0.973-0.997, p < 0.05). Bland & Altman analysis revealed a mean estimation difference of - 0.17 mm (- 2.03%) for polyp size and, a mean difference of - 0.4 mm (- 0.21%) for polyp location. Both differences were statistically non-significant (p > 0.05). When comparing the proposed method with calliper measurements, the Bland & Altman plots showed 95% of size estimation differences between - 1.4 and 1.8 mm (- 13 to 17.4%) which was not significant (p > 0.05). CONCLUSIONS: The proposed method of measurements of polyp size and location was found to be highly accurate, offering great potential for clinical implementation to improve polyp assessment. This level of performance represents a notable improvement over visual estimation technique used in clinical practice.
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Endoscopia Gastrointestinal , Animais , Suínos , Reprodutibilidade dos Testes , Endoscopia Gastrointestinal/métodos , Pólipos/patologiaRESUMO
Oligotrophic mountain lakes act as sensitive indicators of landscape-scale changes in mountain regions due to their low nutrient concentration and remote, relatively undisturbed watersheds. Recent research shows that phosphorus (P) concentrations are increasing in mountain lakes around the world, creating more mesotrophic states and altering lake ecosystem structure and function. The relative importance of atmospheric deposition and climate-driven changes to local biogeochemistry in driving these shifts is not well established. In this study, we test whether increasing temperatures in watershed soils may be contributing to the observed increases in mountain lake P loading. Specifically, we test whether higher soil temperatures increase P mobilization from mountain soils by accelerating the rate of geochemical weathering and soil organic matter decomposition. We used paired soil incubation (lab) and soil transplant (field) experiments with mountain soils from around the western United States to test the effects of warming on rain-leachable P concentration, soil P mobilization, and soil respiration. Our results show that while higher temperature can increase soil P mobilization, low soil moisture can limit the effects of warming in some situations. Soils with lower bulk densities, higher pH, lower aluminum oxide contents, and lower ratios of carbon to nitrogen had much higher rain-leachable P concentration across all sites and experimental treatments. Together, these results suggest that mountain watersheds with high-P soils and relatively high soil moisture could have the largest increases in P mobilization with warming. Consequently, lakes and streams in such watersheds could become especially susceptible to soil-driven eutrophication as temperatures rise.
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BACKGROUND: This study investigated the mediating and moderating impact of core self-evaluations in the path from emotional labor to burnout. Our hypothesized associations are based on Hobfoll (Rev Gen Psychol 6:307-24, 2002) conservation of resources theory. METHOD: Three hundred nurses from four hospitals in Abadan, Iran, were invited to participate in our study. Of the 300, 255 completed all sections and questions in our survey for an 85% response rate. The posited direct and indirect effects were evaluated with structural equation modeling and the interaction effects were evaluated with hierarchical moderated regression and simple regression slope plots. RESULT: Deep acting has indirect effects on burnout through core self-evaluations. Though unrelated to surface acting, core self-evaluations moderate its impact: under low core self-evaluations, surface acting is strongly related to emotional exhaustion and inversely related to personal accomplishment, whereas, under high core self-evaluations, surface acting is unrelated to these burnout dimensions. CONCLUSION: Our findings reveal the dual functions of CSE as a psychological resource and buffer to offset the interpersonal demands of patient care. Limitations, directions for future research, and practical implications are discussed.
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Esgotamento Profissional , Enfermeiras e Enfermeiros , Humanos , Autoavaliação Diagnóstica , Irã (Geográfico) , Esgotamento Profissional/psicologia , Esgotamento Psicológico , Inquéritos e QuestionáriosRESUMO
PURPOSE: Polyp size is an important factor that may influence diagnosis and clinical management decision, but estimation by visual inspection during endoscopy is often difficult and subject to error. The purpose of this study is to develop a quantitative approach that enables an accurate and objective measurement of polyp size and to study the feasibility of the method. METHODS: We attempted to estimate polyp size and location relative to the gastro-oesophageal junction by integrating data from an electromagnetic tracking sensor and endoscopic images. This method is based on estimation of the three-dimensional coordinates of the borders of the polyp by combining the endoscope camera position and the corresponding points along the polyp border in endoscopic images using a computer vision-based algorithm. We evaluated the proposed method using a simulated upper gastrointestinal endoscopy model. RESULTS: The difference between the mean of ten measurements of one artificial polyp and its actual size (10 mm in diameter) was 0.86 mm. Similarly, the difference between the mean of ten measurements of the polyp distance from the gastroesophageal junction and its actual distance (~ 22 cm) was 1.28 mm. Our results show that the changes in camera positions in which the images were taken and the quality of the polyp segmentation have the most impact on the accuracy of polyp size estimation. CONCLUSION: This study demonstrated an innovative approach to endoscopic measurements using motion tracking technologies and computer vision and demonstrated its accuracy in determining the size and location of the polyp. The observed magnitude of error is clinically acceptable, and the measurements are available immediately after the images captured. To enhance accuracy, it is recommended to avoid identical images and instead utilise control wheels on the endoscope for capturing different views. Future work should further evaluate this innovative method during clinical endoscopic procedures.
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Pólipos do Colo , Neoplasias Gastrointestinais , Humanos , Endoscopia Gastrointestinal , Endoscópios , Movimento (Física) , Algoritmos , Pólipos do Colo/diagnóstico , Colonoscopia/métodosRESUMO
BACKGROUND: The 2018 United Network for Organ Sharing (UNOS) heart transplant policy change (PC) sought to improve waitlist risk stratification to decrease waitlist mortality and promote geographically broader sharing for high-acuity patients awaiting heart transplantation. Our analysis sought to determine the effect of the UNOS PC on outcomes in patients waiting for, or who have received, a heart-kidney transplantation. METHODS: We analyzed adult (≥18 years old), first-time, heart-only and heart-kidney transplant candidates and recipients from the UNOS Registry. Patients were divided into pre-PC (PRE: October 18, 2016-May 30, 2018) and post-PC (POST: October 18, 2018-May 30, 2020) groups for comparison. Competing risks analysis (subdistribution and cause-specific hazards analyses) was performed to assess for differences in waitlist death/deterioration or heart transplantation. One-year post-transplant survival was assessed with Kaplan-Meier and Cox analyses. We included an interaction term (policy era × heart ± kidney) in our analyses to evaluate the effect of PC on outcomes in heart-kidney patients. RESULTS: One-year post-transplant survival was similar (p = 0.83) for PRE heart-kidney and heart-only recipients, but worse (p < 0.001) for POST heart-kidney vs heart-only recipients. There was a policy-era interaction between heart-kidney and heart-only recipients (HR 1.92[1.04,3.55], p = 0.038) indicating a detrimental effect of policy on 1-year survival in POST vs PRE heart-kidney recipients. No added beneficial effect of PC on waitlist outcomes in heart-kidney vs heart-only candidates was observed. CONCLUSIONS: There was no added policy-era benefit on waitlist outcomes for heart-kidney candidates when compared to heart-only candidates. POST heart-kidney recipients experienced worse 1-year survival compared to PRE heart-kidney recipients with no policy effect on heart-only recipients.
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Transplante de Coração , Transplante de Rim , Adulto , Humanos , Adolescente , Medição de Risco , Listas de Espera , Estudos Retrospectivos , RimRESUMO
Cardiotocography (CTG) is a widely used technique to monitor fetal heart rate (FHR) during labour and assess the health of the baby. However, visual interpretation of CTG signals is subjective and prone to error. Automated methods that mimic clinical guidelines have been developed, but they failed to improve detection of abnormal traces. This study aims to classify CTGs with and without severe compromise at birth using routinely collected CTGs from 51,449 births at term from the first 20 min of FHR recordings. Three 1D-CNN and LSTM based architectures are compared. We also transform the FHR signal into 2D images using time-frequency representation with a spectrogram and scalogram analysis, and subsequently, the 2D images are analysed using a 2D-CNNs. In the proposed multi-modal architecture, the 2D-CNN and the 1D-CNN-LSTM are connected in parallel. The models are evaluated in terms of partial area under the curve (PAUC) between 0-10% false-positive rate; and sensitivity at 95% specificity. The 1D-CNN-LSTM parallel architecture outperformed the other models, achieving a PAUC of 0.20 and sensitivity of 20% at 95% specificity. Our future work will focus on improving the classification performance by employing a larger dataset, analysing longer FHR traces, and incorporating clinical risk factors.
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BACKGROUND: The 2018 adult heart allocation policy sought to improve waitlist risk stratification, reduce waitlist mortality, and increase organ access. This system prioritized patients at greatest risk for waitlist mortality, especially individuals requiring temporary mechanical circulatory support (tMCS). Posttransplant complications are significantly higher in patients on tMCS before transplantation, and early posttransplant complications impact long-term mortality. We sought to determine if policy change affected early posttransplant complication rates of rejection, infection, and hospitalization. METHODS: We included all adult, heart-only, single-organ heart transplant recipients from the UNOS registry with pre-policy (PRE) individuals transplanted between November 1, 2016, and October 31, 2017, and post-policy (POST) between November 1, 2018, and October 31, 2019. We used a multivariable logistic regression analysis to assess the effect of policy change on posttransplant rejection, infection, and hospitalization. Two COVID-19 eras (2019-2020, 2020-2021) were included in our analysis. RESULTS: The majority of baseline characteristics were comparable between PRE and POST era recipients. The odds of treated rejection (p = 0.8), hospitalization (p = 0.69), and hospitalization due to rejection (p = 0.76) and infection (p = 0.66) were similar between PRE and POST eras; there was a trend towards reduced odds of rejection (p = 0.08). In both COVID eras, there was a clear reduction in rejection and treated rejection with no effect on hospitalization for rejection or infection. Odds of all-cause hospitalization was increased in both COVID eras. CONCLUSIONS: The UNOS policy change improves access to heart transplantation for higher acuity patients without increasing early posttransplant rates of treated rejection or hospitalization for rejection or infection, factors which portend risk for long-term posttransplant mortality.
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COVID-19 , Transplante de Coração , Adulto , Humanos , Readmissão do Paciente , COVID-19/epidemiologia , Transplante de Coração/efeitos adversos , Hospitalização , Políticas , Listas de Espera , Estudos RetrospectivosRESUMO
The Gene Ontology (GO) knowledgebase (http://geneontology.org) is a comprehensive resource concerning the functions of genes and gene products (proteins and noncoding RNAs). GO annotations cover genes from organisms across the tree of life as well as viruses, though most gene function knowledge currently derives from experiments carried out in a relatively small number of model organisms. Here, we provide an updated overview of the GO knowledgebase, as well as the efforts of the broad, international consortium of scientists that develops, maintains, and updates the GO knowledgebase. The GO knowledgebase consists of three components: (1) the GO-a computational knowledge structure describing the functional characteristics of genes; (2) GO annotations-evidence-supported statements asserting that a specific gene product has a particular functional characteristic; and (3) GO Causal Activity Models (GO-CAMs)-mechanistic models of molecular "pathways" (GO biological processes) created by linking multiple GO annotations using defined relations. Each of these components is continually expanded, revised, and updated in response to newly published discoveries and receives extensive QA checks, reviews, and user feedback. For each of these components, we provide a description of the current contents, recent developments to keep the knowledgebase up to date with new discoveries, and guidance on how users can best make use of the data that we provide. We conclude with future directions for the project.
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Bases de Dados Genéticas , Proteínas , Ontologia Genética , Proteínas/genética , Anotação de Sequência Molecular , Biologia ComputacionalRESUMO
OBJECTIVES: We reviewed 594 consecutive patients with Coronavirus Disease 2019 supported with extracorporeal membrane oxygenation at 49 hospitals within 21 states and examined patient characteristics, treatments, and variation in outcomes over the course of the pandemic. METHODS: A multi-institutional database was used to assess all patients with Coronavirus Disease 2019 cannulated for extracorporeal membrane oxygenation between March 17, 2020, and December 20, 2021, inclusive, and separated from ECMO on or prior to January 14, 2022. Descriptive analysis was stratified by 4 time categories: group A = March 2020 to June 2020, group B = July 2020 to December 2020, group C = January 2021 to June 2021, group D = July 2021 to December 2021. A Bayesian mixed-effects logistic regression was used to assess continuous trends in survival where time was operationalized as the number of days between each patient's cannulation and that of the first patient in March 2020, controlling for multiple variables and risk factors. RESULTS: At hospital discharge, of 594 patients, 221 survived (37.2%) and 373 died. Throughout the study, median age [interquartile range] declined (group A = 51.0 [41.0-60.0] years, group D = 39.0 [32.0-48.0] years, P < .001); median days between Coronavirus Disease 2019 diagnosis and intubation increased (group A = 4.0 [1.0-8.5], group D = 9.0 [5.0-14.5], P < .001); and use of medications (glucocorticoids, interleukin-6 blockers, antivirals, antimalarials) and convalescent plasma fluctuated significantly (all P < .05). Estimated odds of survival varied over the study period with a decline between April 1, 2020, and November 21, 2020 (odds ratio, 0.39, 95% credible interval, 0.18-0.87, probability of reduction in survival = 95.7%), improvement between November 21, 2020, and May 17, 2021 (odds ratio, 1.85, 95% credible interval, 0.86-4.09, probability of improvement = 93.4%), and decline between May 17, 2021, and December 1, 2021 (odds ratio, 0.49, 95% credible interval, 0.19-1.44, probability of decrease = 92.1%). CONCLUSIONS: Survival for patients with Coronavirus Disease 2019 supported with extracorporeal membrane oxygenation has fluctuated during the stages of the pandemic. Minimizing variability by adherence to best practices may refine the optimal use of extracorporeal membrane oxygenation in a pandemic response.
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COVID-19 , Oxigenação por Membrana Extracorpórea , Humanos , Pessoa de Meia-Idade , Oxigenação por Membrana Extracorpórea/efeitos adversos , Teorema de Bayes , COVID-19/terapia , Soroterapia para COVID-19 , Hospitais , Estudos Multicêntricos como AssuntoRESUMO
BACKGROUND: Lower back pain (LBP) is a principal cause of disability worldwide and is associated with a variety of spinal conditions. Individuals presenting with LBP may display changes in spinal motion. Despite this, the ability to measure lumbar segmental range of motion (ROM) non-invasively remains a challenge. OBJECTIVE: To review the reliability of four non-invasive modalities: Video Fluoroscopy (VF), Ultrasound imaging (US), Magnetic Resonance Imaging (MRI) and Radiography used for measuring segmental ROM in the lumbar spine in-vivo. METHODS: The methodological quality of seventeen eligible studies, identified through a systematic literature search, were appraised. RESULTS: The intra-rater reliability for VF is excellent in recumbent and upright positions but errors are larger for intra-rater repeated movements and inter-rater reliability shows larger variation. Excellent results for intra- and inter-rater reliability are seen in US studies and there is good reliability within- and between-day. There is a large degree of heterogeneity in MRI and radiography methodologies but reliable results are seen. CONCLUSIONS: Excellent reliability is seen across all modalities. However, VF and radiography are limited by radiation exposure and MRI is expensive. US offers a non-invasive, risk free method but further research must determine whether it yields truly consistent measurements.
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Dor Lombar , Vértebras Lombares , Humanos , Reprodutibilidade dos Testes , Vértebras Lombares/diagnóstico por imagem , Amplitude de Movimento Articular , Radiografia , Imageamento por Ressonância Magnética , Dor Lombar/diagnóstico por imagem , Ultrassonografia , FluoroscopiaRESUMO
Repair of concomitant aortic and mitral valvular disease with involvement of the aortomitral curtain requires a technically complex operation colloquially termed the commando procedure. Surgical outcomes of this procedure are not well described. The objective of this study was to examine outcomes of the commando procedure at our center. We identified all patients undergoing concomitant aortic and mitral valve replacements from 2004-2021. Of 363 patients, 41 underwent reconstruction of the aortomitral curtain. Survival analysis and multivariable modeling were used to examine outcomes and risk factors for mortality. The median age was 52 (IQR 44-71) years. Preoperatively, 4 of 41 (9.8%) patients had renal failure, and 10 of 41 (24.4%) had a stroke. The most common surgical indication was endocarditis in 25 of 41 (61.0%) patients. 25 of 41 (61.0%) patients underwent redo sternotomy, and 23 of 41 (56.1%) had previous prosthetic valves. Operative mortality was 14 of 41 (34.1%), and 8 of 41 (9.5%) patients received a permanent pacemaker. Survival at 1, 3, and 5 years was 55.4% (95% confidence interval (CI), 40.6-75.5%), 50.3% (35.0-72.3%), and 37.7% (19.3-73.9%) respectively. Cox proportional hazards regression identified previous sternotomy (HR 4.76, 95% CI 1.21-18.73), and female gender (HR 1.39, 95% CI 1.17-13.82) as risk factors for mortality. Patients undergoing reconstruction of the aortomitral curtain represent a high-risk population with complex surgical indications. Due to high perioperative morbidity and mortality, this procedure should be performed only when necessary. Despite a high up front morbidity burden, outcomes remain favorable for patients who survive the initial hospitalization.
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Two critically ill COVID-19 infected patients, who had exhausted all available treatment options, were treated with the small-molecule RRx-001 with subsequent improvement. RRx-001, a first-in-class small molecule with anti-inflammatory, vascular normalizing and macrophage-repolarizing properties, has been safely administered 300+ patients in clinical trials. This is the first report of RRx-001 treatment of COVID-19.
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In Arctic catchments, bacterioplankton are dispersed through soils and streams, both of which freeze and thaw/flow in phase, seasonally. To characterize this dispersal and its potential impact on biogeochemistry, we collected bacterioplankton and measured stream physicochemistry during snowmelt and after vegetation senescence across multiple stream orders in alpine, tundra, and tundra-dominated-by-lakes catchments. In all catchments, differences in community composition were associated with seasonal thaw, then attachment status (i.e. free floating or sediment associated), and then stream order. Bacterioplankton taxonomic diversity and richness were elevated in sediment-associated fractions and in higher-order reaches during snowmelt. Families Chthonomonadaceae, Pyrinomonadaceae, and Xiphinematobacteraceae were abundantly different across seasons, while Flavobacteriaceae and Microscillaceae were abundantly different between free-floating and sediment-associated fractions. Physicochemical data suggested there was high iron (Fe+ ) production (alpine catchment); Fe+ production and chloride (Cl- ) removal (tundra catchment); and phosphorus (SRP) removal and ammonium (NH4 + ) production (lake catchment). In tundra landscapes, these 'hot spots' of Fe+ production and Cl- removal accompanied shifts in species richness, while SRP promoted the antecedent community. Our findings suggest that freshet increases bacterial dispersal from headwater catchments to receiving catchments, where bacterioplankton-mineral relations stabilized communities in free-flowing reaches, but bacterioplankton-nutrient relations stabilized those punctuated by lakes.
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Lagos , Plâncton , Humanos , Regiões Árticas , Lagos/química , Bactérias/genética , Fósforo , Organismos AquáticosRESUMO
Physical activity brings significant health benefits to middle-aged adults, although the research to date has been focused on late adulthood. This study aims to examine how ageing affects the self-reported and accelerometer-derived measures of physical activity levels in middle-aged adults. We employed the data recorded in the UK Biobank and analysed the physical activity levels of 2,998 participants (1381 men and 1617 women), based on self-completion questionnaire and accelerometry measurement of physical activity. We also assessed the musculoskeletal health of the participants using the dual-energy X-ray absorptiometry (DXA) measurements provided by the UK Biobank. Participants were categorised into three groups according to their age: group I younger middle-aged (40 to 49 years), group II older middle-aged (50 to 59 years), and group III oldest middle-aged (60 to 69 years). Self-reported physical activity level increased with age and was the highest in group III, followed by group II and I (P < 0.05). On the contrary, physical activity measured by accelerometry decreased significantly with age from group I to III (P < 0.05), and the same pertained to the measurements of musculoskeletal health (P < 0.05). It was also shown that middle-aged adults mostly engaged in low and moderate intensity activities. The opposing trends of the self-reported and measured physical activity levels may suggest that middle-aged adults over-report their activity level as they age. They should be aware of the difference between their perceived and actual physical activity levels, and objective measures would be useful to prevent the decline in musculoskeletal health.