176 research outputs found

    The Effect of Temperature on the Reproductive Success of Male Waterbugs (Belostoma flumineum)

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    Sexual selection theory predicts that the sex that shows a greater parental investment in the offspring should be limiting to the reproductive success of the opposite sex. Males of the giant waterbug Belostoma flumineum exhibit greater parental investment than females by providing all of the parental care for the eggs, which are firmly attached to their dorsal surface. While male backspace availability can be limiting to female reproductive success, it has previously been found to be more limiting during the spring than during the fall, due to newly emerged males being able to breed more quickly than newly emerged females. In light of different thermal regimes in the two breeding seasons, this study examined the relationship between ambient temperature and male backspace availability. Males were exposed to one of four temperature treatments within the laboratory: mating and brooding at 20°C, mating at 20°C and brooding at 26°C, mating at 26°C and brooding at 20°C, or mating and brooding at 26°C. Overall, the size of the egg pad was larger and the time until mating was shorter for males that mated at 26°C, while the time spent brooding was longer for males that brooded at 20°C. The proportion of males that received an additional egg pad, when they had the opportunity, was found to be greater than that of males that received any egg pads at all. While the temperature treatment and the number of brooding attempts were not associated with the result of brooding, the rate of brooder mortality was found to be higher than that of nonbrooders when males were exposed to different mating and brooding temperatures. The high rate of brooder mortality, in addition to the delayed date of mating events and relatively long brooding periods observed in this study, are not consistent with previous studies and may be due to a recent change in the natural population of B. flumineum

    Opracowanie ogólnego modelu funkcjonowania systemu informacyjnego rachunkowości na przedsiębiorstwie

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    Na podstawie przeprowadzonej analizy istoty podejmowania decyzji zarządczych i mechanizmu oceny skuteczności ich przyjęcia, w artykule zaproponowano uogólniony model funkcjonowania. Schematycznie przedstawiono etapy funkcjonowania proponowanego systemu informacyjno-analitycznego, które otwierają logiczną sekwencję wpływów, analizy i przetwarzania informacji. W opracowanym modelu przyjęto, że informacje ze środowiska zewnętrznego przez adaptacyjny filtr trafiają do ośrodka informacyjno-analitycznego systemu rachunkowości, gdzie powstają kompleksowe systematyzowane dane do przygotowania wariantów projektów decyzji, które w przyszłości będą realizowane. Opracowany model w przypadku jego wprowadzenia na przedsiębiorstwo pozwoli przygotować optymalne rozwiązania organizacyjne

    Histogram-based models on non-thin section chest CT predict invasiveness of primary lung adenocarcinoma subsolid nodules.

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    109 pathologically proven subsolid nodules (SSN) were segmented by 2 readers on non-thin section chest CT with a lung nodule analysis software followed by extraction of CT attenuation histogram and geometric features. Functional data analysis of histograms provided data driven features (FPC1,2,3) used in further model building. Nodules were classified as pre-invasive (P1, atypical adenomatous hyperplasia and adenocarcinoma in situ), minimally invasive (P2) and invasive adenocarcinomas (P3). P1 and P2 were grouped together (T1) versus P3 (T2). Various combinations of features were compared in predictive models for binary nodule classification (T1/T2), using multiple logistic regression and non-linear classifiers. Area under ROC curve (AUC) was used as diagnostic performance criteria. Inter-reader variability was assessed using Cohen's Kappa and intra-class coefficient (ICC). Three models predicting invasiveness of SSN were selected based on AUC. First model included 87.5 percentile of CT lesion attenuation (Q.875), interquartile range (IQR), volume and maximum/minimum diameter ratio (AUC:0.89, 95%CI:[0.75 1]). Second model included FPC1, volume and diameter ratio (AUC:0.91, 95%CI:[0.77 1]). Third model included FPC1, FPC2 and volume (AUC:0.89, 95%CI:[0.73 1]). Inter-reader variability was excellent (Kappa:0.95, ICC:0.98). Parsimonious models using histogram and geometric features differentiated invasive from minimally invasive/pre-invasive SSN with good predictive performance in non-thin section CT

    The relationship between physical activity and lymphoma: a systematic review and meta analysis

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    BACKGROUND: The literature suggests an increased risk between anthropometrics including higher body mass index and lymphoma incidence; however, the association with physical activity remains unclear. A systematic review/meta-analysis was therefore performed to examine this association with physical activity (total, recreational or occupational). METHODS: PubMed, Web of Science and Embase were reviewed from inception to October 2019 identifying relevant observational studies. Non-Hodgkin lymphoma (NHL) including subtypes diffuse large B cell lymphoma, follicular lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, and Hodgkin lymphoma (HL) were analyzed. Included studies reported activity, lymphoma cases, effect size and variability measures, and were restricted to human subjects of any age. Data was pooled generating summary relative risk (RR) estimates with 95% confidence intervals (CI) using random-effects models with primary outcome of histologically confirmed incident lymphoma. RESULTS: One thousand four hundred studies were initially identified with 18 studies (nine cohort, nine case-control) included in final analysis. Comparing highest vs. lowest activity categories was protective for all lymphoma (RR 0.89, 95%CI 0.81-0.98). Sensitivity analysis demonstrated effect persistence within case-control studies (RR 0.82, 95% CI 0.71-0.96), but not cohort studies (RR 0.95, 95%CI 0.84-1.07). Borderline protective effect was seen for NHL (RR 0.92, 95%CI 0.84-1.00), but not HL (RR 0.72, 95%CI 0.50-1.04). Analysis by NHL subtype or gender showed no effect. Dose response analysis demonstrated a protective effect (p = 0.034) with a 1% risk reduction per 3 MET hours/week (RR 0.99, 95%CI 0.98-1.00). CONCLUSIONS: Physical activity may have a protective effect against lymphoma development; further studies are required to generate recommendations regarding health policy. TRIAL REGISTRATION: This study was registered prospectively at PROSPERO: CRD42020156242

    Physical activity level and stroke risk in US population: A matched case-control study of 102,578 individuals

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    Background: Stroke has been linked to a lack of physical activity; however, the extent of the association between inactive lifestyles and stroke risk has yet to be characterized across large populations. Purpose: This study aimed to explore the association between activity-related behaviors and stroke incidence. Methods: Data from 1999 to 2018 waves of the concurrent cross-sectional National Health and Nutrition Examination Survey (NHANES) were extracted. We analyzed participants characteristics and outcomes for all participants with data on whether they had a stroke or not and assessed how different forms of physical activity affect the incidence of disease. Results: Of the 102,578 individuals included, 3851 had a history of stroke. A range of activity-related behaviors was protective against stroke, including engaging in moderate-intensity work over the last 30 days (OR = 0.8, 95% CI = 0.7-0.9; P = 0.001) and vigorous-intensity work activities over the last 30 days (OR = 0.6, 95% CI = 0.5-0.8; P \u3c 0.001), and muscle-strengthening exercises (OR = 0.6, 95% CI = 0.5-0.8; P \u3c 0.001). Conversely, more than 4 h of daily TV, video, or computer use was positively associated with the likelihood of stroke (OR = 11.7, 95% CI = 2.1-219.2; P = 0.022). Conclusion: Different types, frequencies, and intensities of physical activity were associated with reduced stroke incidence, implying that there is an option for everyone. Daily or every other day activities are more critical in reducing stroke than reducing sedentary behavior duration

    Acute ischaemic stroke associated with SARS-CoV-2 infection in North America

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    BACKGROUND: To analyse the clinical characteristics of COVID-19 with acute ischaemic stroke (AIS) and identify factors predicting functional outcome. METHODS: Multicentre retrospective cohort study of COVID-19 patients with AIS who presented to 30 stroke centres in the USA and Canada between 14 March and 30 August 2020. The primary endpoint was poor functional outcome, defined as a modified Rankin Scale (mRS) of 5 or 6 at discharge. Secondary endpoints include favourable outcome (mRS ≤2) and mortality at discharge, ordinal mRS (shift analysis), symptomatic intracranial haemorrhage (sICH) and occurrence of in-hospital complications. RESULTS: A total of 216 COVID-19 patients with AIS were included. 68.1% (147/216) were older than 60 years, while 31.9% (69/216) were younger. Median [IQR] National Institutes of Health Stroke Scale (NIHSS) at presentation was 12.5 (15.8), and 44.2% (87/197) presented with large vessel occlusion (LVO). Approximately 51.3% (98/191) of the patients had poor outcomes with an observed mortality rate of 39.1% (81/207). Age \u3e60 years (aOR: 5.11, 95% CI 2.08 to 12.56, p\u3c0.001), diabetes mellitus (aOR: 2.66, 95% CI 1.16 to 6.09, p=0.021), higher NIHSS at admission (aOR: 1.08, 95% CI 1.02 to 1.14, p=0.006), LVO (aOR: 2.45, 95% CI 1.04 to 5.78, p=0.042), and higher NLR level (aOR: 1.06, 95% CI 1.01 to 1.11, p=0.028) were significantly associated with poor functional outcome. CONCLUSION: There is relationship between COVID-19-associated AIS and severe disability or death. We identified several factors which predict worse outcomes, and these outcomes were more frequent compared to global averages. We found that elevated neutrophil-to-lymphocyte ratio, rather than D-Dimer, predicted both morbidity and mortality
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