37 research outputs found

    Ground beetle assemblages in Beijing’s new mountain forests

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    Mature forests have been almost completely destroyed in China’s northern regions, but this has been followed by large-scale reforestation in the wake of environmental degradation. Although future forest plantations are expected to expand over millions of hectares, knowledge about the ecology and biodiversity of China’s replanted forests remains very limited. Addressing these knowledge gaps, we recorded ground beetle (Coleoptera: Carabidae) communities in five secondary forest types: plantations of Chinese Pine (Pinus tabulaeformis) and Prince Rupprecht’s Larch (Larix principis-rupprechtii), Oak (Quercus wutaishanica) and Asian White Birch (Betula platyphylla) woodlands, and naturally regenerated mixed forest. Species richness peaked in mixed forests, while pine and oak woodlands harboured discrete communities of intermediate species richness. Oak, pine and mixed forest habitats also showed high levels of species turnover between plots. Canopy closure was an important factor influencing ground beetle assemblages and diversity, and a number of forest specialist species only occurred in pine or oak forests. We believe that some forest specialists have survived earlier deforestation and appear to be supported by new plantation forests, but maintenance of secondary native oak and mixed forests is crucial to safeguard the overall species pool

    Stomatal Opening Involves Polar, Not Radial, Stiffening Of Guard Cells

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    It has long been accepted that differential radial thickening of guard cells plays an important role in the turgor-driven shape changes required for stomatal pore opening to occur [1-4]. This textbook description derives from an original interpretation of structure rather than measurement of mechanical properties. Here we show, using atomic force microscopy, that although mature guard cells display a radial gradient of stiffness, this is not present in immature guard cells, yet young stomata show a normal opening response. Finite element modeling supports the experimental observation that radial stiffening plays a very limited role in stomatal opening. In addition, our analysis reveals an unexpected stiffening of the polar regions of the stomata complexes, both in Arabidopsis and other plants, suggesting a widespread occurrence. Combined experimental data (analysis of guard cell wall epitopes and treatment of tissue with cell wall digesting enzymes, coupled with bioassay of guard cell function) plus modeling lead us to propose that polar stiffening reflects a mechanical, pectin-based pinning down of the guard cell ends, which restricts increase of stomatal complex length during opening. This is predicted to lead to an improved response sensitivity of stomatal aperture movement with respect to change of turgor pressure. Our results provide new insight into the mechanics of stomatal function, both negating an established view of the importance of radial thickening and providing evidence for a significant role for polar stiffening. Improved stomatal performance via altered cell-wall-mediated mechanics is likely to be of evolutionary and agronomic significance

    Booster vaccination against SARS-CoV-2 induces potent immune responses in people with human immunodeficiency virus

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    Background People with human immunodeficiency virus (HIV) on antiretroviral therapy (ART) with good CD4 T-cell counts make effective immune responses following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). There are few data on longer term responses and the impact of a booster dose. Methods Adults with HIV were enrolled into a single arm open label study. Two doses of ChAdOx1 nCoV-19 were followed 12 months later by a third heterologous vaccine dose. Participants had undetectable viraemia on ART and CD4 counts >350 cells/”L. Immune responses to the ancestral strain and variants of concern were measured by anti-spike immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA), MesoScale Discovery (MSD) anti-spike platform, ACE-2 inhibition, activation induced marker (AIM) assay, and T-cell proliferation. Findings In total, 54 participants received 2 doses of ChAdOx1 nCoV-19. 43 received a third dose (42 with BNT162b2; 1 with mRNA-1273) 1 year after the first dose. After the third dose, total anti-SARS-CoV-2 spike IgG titers (MSD), ACE-2 inhibition, and IgG ELISA results were significantly higher compared to Day 182 titers (P < .0001 for all 3). SARS-CoV-2 specific CD4+ T-cell responses measured by AIM against SARS-CoV-2 S1 and S2 peptide pools were significantly increased after a third vaccine compared to 6 months after a first dose, with significant increases in proliferative CD4+ and CD8+ T-cell responses to SARS-CoV-2 S1 and S2 after boosting. Responses to Alpha, Beta, Gamma, and Delta variants were boosted, although to a lesser extent for Omicron. Conclusions In PWH receiving a third vaccine dose, there were significant increases in B- and T-cell immunity, including to known variants of concern (VOCs)

    The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

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    Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

    Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

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    BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

    Marketing activities and household activities of country hawkers in Barbados.

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    [...] The present study, which is intended to supplement the growing body of literature concerned with small-scale traders and marketers in peasant economies, will investigate the nature of the distributive activities of rural Negro women in the Scotland District of Barbados. The various types of distribution will be described in terms of the economic relationships within which internal distribution is conducted. The household roles of Scotland District women will be examined to determine possible relationships between particular roles and particular distributive occupations, and changes from one type of distribution to another will be related to the life cycle of the woman. The household situtations of Scotland District distributors will be compared to those of non-distributors. [...

    Response to Vincenti

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    Development of an Assessment to Examine Training of the Hospice Primary Caregiver

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    BACKGROUND: Key to high-quality care of dying hospice patients at home is whether the hospice provides adequate training so the caregiver can safely care for the patient. OBJECTIVE: The study objective was to develop and validate a survey of hospice training for caregivers to ensure safe, high-quality care in the home setting. DESIGN: Our survey design was cross-sectional. Bereaved respondents of individuals who died at home under the care of hospice were surveyed three to six months postdeath. MEASUREMENTS: Items were developed based on advice of an expert panel, focus groups of hospice caregivers, and literature review, with 12 items developed for testing and examining 8 key processes of care. We examined the validity and reliability of the assessment using factor analysis, correlational analyses, and multivariable modeling. RESULTS: Our sample consisted of 262 primary caregivers (mean age 62.4, 76.7% female, 58.8% non-Hispanic white). Six questions focused on providing the caregiver with information, while another six focused on the training that hospice provided. Based on model fit and Cronbach\u27s alpha, we dropped the information items. The items that examined hospice training demonstrated a one-factor solution and a Cronbach\u27s of 0.90. We examined correlations of the multi-item composite with overall rating of quality of care (0.53), overall distress (0.31), and whether the respondent would recommend this hospice to others (0.49). There were no significant sociodemographic correlates of concerns with training. CONCLUSIONS: Sufficient preliminary reliability and validity warrants further testing of this composite to examine the adequacy of training provided to family members to care safely for the patient

    Using entomopathogenic fungi to control the greenhouse whitefly (Trialeurodes vaporariorum): developing a standardised bioassay

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    A standardised bioassay method was created to assess the efficacy of different entomopathogenic fungal isolates against Greenhouse whitefly (Trialeurodes vaporariorum) (GHWF). A spray tower consisting of a gravity feed dual action airbrush attached to an acrylic cylinder and powered by a mini airbrush compressor was calibrated to apply a uniform coverage of solution to a target area. Egg laying by adult GHWF was restricted to a known area of the lateral side of aubergine leaves and migration during the first instar was observed. The spray tower was used to apply a single concentration of eighteen different entomopathogenic fungi (EPF) onto third instar GHWF. Isolates consisted of a mixture of commercially available mycoinsecticides and other isolates taken from the USDA Agricultural Research Service collection, resulting in a mixture of Beauveria, Isaria, Lecanicillium and Metarhizium species. The sprayer delivered 252± 51 fungal spores/mm, equivalent to 2.5 x1012 spores per hectare. Whitefly mortality ranged 8-89% with half of the isolates resulting in <40% GHWF population mortality. The methods employed in this study could be utilised in the selection of isolates for microbial control of whitefly. Combining the sprayer calibration and bioassay method ensures a reliable and applicable approach to test efficacy of whitefly pesticides
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