350 research outputs found
Bradyrhizobium ingae sp. nov., isolated from effective nodules of Inga laurina grown in Cerrado soil
Root-nodule bacteria were isolated from lnga laurina (Sw.) Willd. growing in the Cerrado Amazon region, State of Roraima, Brazil. The 16S rRNA gene sequences of six strains (BR 10250(T), BR 10248, BR 10249, BR 10251, BR 10252 and BR 10253) showed low similarities with currently described species of the genus Bradyrhizobium. Phylogenetic analyses of sequences of five housekeeping genes (dnaK, gyrB, recA and rpoB) revealed Bradyrhizobium iriomotense EKO5(T) to be the closest type strain (97.4% sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [with the major components C-16:0 and summed feature 8 (C-18:1 omega 6c/C-18:1 omega 7c)], the slow growth rate and carbon compound utilization patterns supported the assignment of our strains to the genus Bradyrhizobium. Results from DNA DNA hybridizations and physiological traits differentiated our strains from the closest related species of the genus Bradyrhizobium with validly published names. Sequences of symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) grouped together with those of B. iriomotense EKO5(T) and Bradyrhizobium sp. strains BR 6610 (used as a commercial inoculant for Inga marginata in Brazil) and TUXTLAS-10 (previously observed in Central America). Based on these data, the six strains represent a novel species, for which the name Bradyrhizobium ingae sp. nov. is proposed. The type strain is BR 10250(T) (=HAMBI 3600(T))
Bradyrhizobium neotropicale sp. nov., isolated from effective nodules of Centrolobium paraense
Root nodule bacteria were isolated from Centrolobium paraense Tul. grown in soils from the Amazon region, State of Roraima (Brazil). 16S rRNA gene sequence analysis of seven strains (BR 10247(T), BR 10296, BR 10297, BR 10298, BR 10299, BR 10300 and BR 10301) placed them in the genus Bradyrhizobium with the closest neighbours being the type strains of Bradyrhizobium paxllaeri (98.8 % similarity), Bradyrhizobium icense (98.8 %), Bradyrhizobium lablabi (98.7 %), Bradyrhizobium jicamae (98.6 %), Bradyrhizobium elkanii (98.6 %), Bradyrhizobium pachyrhizi (98.6%) and Bradyrhizobium retamae (98.3 %). This high similarity, however, was not confirmed by the intergenic transcribed spacer (ITS) 16S-23S rRNA region sequence analysis nor by multi-locus sequence analysis. Phylogenetic analyses of five housekeeping genes (dnaK, gin/I, gyrB, recA and rpoB) revealed Bradyrhizobium iriomotense EKO5(T) (=LMG 24129(T)) to. be the most closely related type strain (95.7% sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [major components being C-16:0 and summed feature 8 (18:1 omega 6c/18:1 omega 7c)] DNA G+C content, slow growth rate and carbon compound utilization patterns, supported the placement of the novel strains in the genus Bradyrhizobium. Results of DNA-DNA relatedness studies and physiological data (especially carbon source utilization) differentiated the strains from the closest recognized species of the genus Bradyrhizobium. Symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nil/-I) placed the novel species in a new branch within the genus Bradyrhizobium. Based on the current data, these seven strains represent a novel species for which the name Bradyrhizobium neotropicale sp. nov. is proposed. The type strain is BR 10247(T) (=HAMBI 3599(T))
Disentangling synergistic disease dynamics: Implications for the viral biocontrol of rabbits
European rabbits (Oryctolagus cuniculus) have been exposed to rabbit haemorrhagic disease virus (RHDV) and myxoma virus (MYXV) in their native and invasive ranges for decades. Yet, the long‐term effects of these viruses on rabbit population dynamics remain poorly understood.In this context, we analysed 17 years of detailed capture–mark–recapture data (2000–2016) from Turretfield, South Australia, using a probabilistic state‐space hierarchical modelling framework to estimate rabbit survival and epidemiological dynamics.While RHDV infection and disease‐induced death were most prominent during annual epidemics in winter and spring, we found evidence for continuous infection of susceptible individuals with RHDV throughout the year. RHDV‐susceptible rabbits had, on average, 25% lower monthly survival rates compared to immune individuals, while the average monthly force of infection in winter and spring was ∼38%. These combined to result in an average infection‐induced mortality rate of 69% in winter and spring.Individuals susceptible to MYXV and immune to RHDV had similar survival probabilities to those having survived infections from both viruses, whereas individuals susceptible to both RHDV and MYXV had higher survival probabilities than those susceptible to RHDV and immune to MYXV. This suggests that MYXV may reduce the future survival rates of individuals that endure initial MYXV infection.There was no evidence for long‐term changes in disease‐induced mortality and infection rates for either RHDV or MYXV.We conclude that continuous, year‐round virus perpetuation (and perhaps heterogeneity in modes of transmission and infectious doses during and after epidemics) acts to reduce the efficiency of RHDV and MYXV as biocontrol agents of rabbits in their invasive range. However, if virulence can be maintained as relatively constant through time, RHDV and MYXV will likely continue realizing strong benefits as biocontrol agents
A multirisk approach to predicting chronicity of postpartum depression symptoms
Background: Persistence of postpartum depression (PPD) carries potential adverse implications for the emerging mother–child relationship and for child development. Methods: This study was designed to investigate factors related to the onset and persistence of PPD; in particular, we examined the cumulative effect of a range of psychosocial risk factors in predicting chronic PPD symptoms. One hundred and five women were interviewed at three assessment periods: within the first days after childbirth, at 6 months, and at 18 months postpartum. Results: Depressive symptoms at 6 months predicted 18 months depressive symptoms, even when controlling for the contribution of maternal depression at birth. Psychosocial risk had a moderating influence on the stability of depressive symptomatology. Women with two or more risk factors at birth were more likely to have stable depressive symptomatology across the infants' first 18 months of life. Conclusion: To prevent a chronic course of PPD it may be necessary to identify both depressive symptoms and relevant psychosocial risk factors. Depression and Anxiety 25:718–724, 2008. © 2008 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/60968/1/20419_ftp.pd
Creating Effective, Evidence-Based Video Communication of Public Health Science (COVCOM Study): Protocol for a Sequential Mixed Methods Effect Study
Background:
The nonlinear nature of contagious diseases and the potential for exponential growth can be difficult to grasp for the general public. This has strong implications for public health communication, which needs to be both easily accessible and efficient. A pandemic is an extreme situation, and the accompanying strict societal measures are generally easier to accept if one understands the underlying reasoning behind them. Bringing about informed attitude change and achieving compliance to strict restrictions requires explanations of scientific concepts and terminologies that laypersons can understand.
Objective:
The aim of the project is to develop effective, evidence-based modes of video communication for translating complex, but important, health messages about pandemics to both the general population and decision makers. The study uses COVID-19 as a case to learn and prepare society for handling the ongoing and future pandemics, as well as to provide evidence-based tools for the science communication toolbox.
Methods:
The project applies a mixed methods design, combining qualitative methods (eg, interviews, observational studies, literature reviews) and quantitative methods (eg, randomized controlled trials [RCTs]). The project brings together researchers from a wide range of academic fields, as well as communication industry professionals.
Results:
This study has received funding from the Trond Mohn Foundation through the Research Council of Norway’s “COVID-19 Emergency Call for Proposals” March 2020. Recruitment and data collection for the exploratory first phase of the project ran from February 2021 to March 2021. Creative communication work started in May 2021, and the production of videos for use in the RCTs in the final phase of the project started in September 2021.
Conclusions:
The COVCOM project will take on several grand challenges within the field of communicating science and provide evidence-based tools to the science communication toolbox. A long-term goal of the project is to contribute to the creation of a more resilient health care system by developing communication responses tailormade for different audiences, preparing society for any future pandemic.
International Registered Report Identifier (IRRID):
DERR1-10.2196/3427
Restricted fluid bolus volume in early septic shock: Results of the Fluids in Shock pilot trial
© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ. Objective To determine the feasibility of Fluids in Shock, a randomised controlled trial (RCT) of restricted fluid bolus volume (10 mL/kg) versus recommended practice (20 mL/kg). Design Nine-month pilot RCT with embedded mixed-method perspectives study. Setting 13 hospitals in England. Patients Children presenting to emergency departments with suspected infection and shock after 20 mL/kg fluid. Interventions Patients were randomly allocated (1:1) to further 10 or 20 mL/kg fluid boluses every 15 min for up to 4 hours if still in shock. Main outcome measures These were based on progression criteria, including recruitment and retention, protocol adherence, separation, potential trial outcome measures, and parent and staff perspectives. Results Seventy-five participants were randomised; two were withdrawn. 23 (59%) of 39 in the 10 mL/kg arm and 25 (74%) of 34 in the 20 mL/kg arm required a single trial bolus before the shock resolved. 79% of boluses were delivered per protocol in the 10 mL/kg arm and 55% in the 20 mL/kg arm. The volume of study bolus fluid after 4 hours was 44% lower in the 10 mL/kg group (mean 14.5 vs 27.5 mL/kg). The Paediatric Index of Mortality-2 score was 2.1 (IQR 1.6-2.7) in the 10 mL/kg group and 2.0 (IQR 1.6-2.5) in the 20 mL/kg group. There were no deaths. Length of hospital stay, paediatric intensive care unit (PICU) admissions and PICU-free days at 30 days did not differ significantly between the groups. In the perspectives study, the trial was generally supported, although some problems with protocol adherence were described. Conclusions Participants were not as unwell as expected. A larger trial is not feasible in its current design in the UK. Trial registration number ISRCTN15244462
Sharpening the Precision of the Sunyaev-Zel'dovich Power Spectrum
Using both halo model calculations and a large sample of simulated SZ maps,
we demonstrate that high-mass clusters add significant non-Gaussian variance to
measurements of the SZ power spectrum amplitude. The difficulty in correctly
accounting theoretically for the contribution of these objects to the
uncertainty in C_l leads to a reduced sensitivity to \sigma_8. We show that a
simple solution is to mask out the brightest clusters in the map before
measuring the power spectrum. We demonstrate that fairly conservative masking
can reduce the variance and Gaussianize the statistics significantly, thus
increasing the sensitivity to cosmological parameters. Choosing which objects
to mask is non-trivial; we found that using a fixed sky density produced a
well-defined and well-behaved estimate that can easily be applied to real maps.
For example, masking the 10 (90) brightest clusters in a 100 deg^2 SZ map will
improve the sensitivity to C_l by a factor of two at l = 1000 (2000) and 1.5 at
l = 2000 (4000). We show that even in the presence of astrophysical foregrounds
(primary CMB and point sources) and instrument noise, one can increase the
precision on measurements of \sigma_8 by masking up to 0.9 clusters/deg^2.Comment: 11 pages, 8 figures, submitted to Ap
Postnatal depression in Southern Brazil: prevalence and its demographic and socioeconomic determinants
<p>Abstract</p> <p>Background</p> <p>Studies investigating the prevalence of postnatal depression (PND) show rates ranging from 5% to 36.7%. The investigation of age, race, educational levels, religion and income as risk factors for PND has yielded conflicting results. The aim of this study is to investigate the prevalence of PND in women residing in Southern Brazil and the associated risk factors.</p> <p>Methods</p> <p>This is population-based cross-sectional study of women residing in Porto Alegre who delivered in June 2001. A sample of 271 participants were selected from the Record of Living Newborn Infants of the State Health Department (the official Brazilian database and stores the name and address of all women who give birth to living newborn infants) using a process based on pseudo-random numbers which choose a random sample from 2.000 records. Once the addresses were identified, the women were visited at their place of residence (home, hotel, boarding house and prison), with the interviews taking place between the 6<sup>th </sup>and the 8<sup>th </sup>week after delivery.</p> <p>The association between the risk factors and PND was investigated through bivariate analysis using Pearson's chi-square test. Student's t-test was used to analyze the continuous variables. To identify independent risk factors, multivariate analysis was performed using hierarchical levels with a predefined model that took into account the time relationship between PND and the risk factors. Cox's regression was used to calculate the prevalence ratios.</p> <p>Results</p> <p>The PND prevalence rate found was 20.7% (CI 95% 15.7 – 25.7). After adjusting for confounding variables, per capita income was found to have a significant association with PND.</p> <p>Conclusion</p> <p>The prevalence of PND is higher than the figures found in most developed countries and similar to the figures found in developing countries. Differences in PND by regions or countries can be partially explained by the effect of income on the mediation of risk factors. In low income populations, women should be routinely evaluated for postnatal depression, and those with no partner or spouse are likely to require further care from health services and should be given the benefit of mental health prevention programs.</p
TRY plant trait database - enhanced coverage and open access
Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
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