1,295 research outputs found
Occurrence and diversity of arbuscular mycorrhizal fungi colonising offâseason and inâseason weeds and their relationship with maize yield under conservation agriculture
Weeds are responsible for major crop losses worldwide but can provide beneficial agroecosystem services. This study aimed to elucidate how arbuscular mycorrhizal fungi (AMF) in weeds respond to host identity and conservation agricultural practices. The study was carried out at two locations in Southern Africa during off-season and in-season maize cultivation. Off-season AMF root colonisation, diversity indices and community composition significantly differed among weed species at both locations. Glomus sp. VTX00280 explains most of the AMF community differences. In-season, implementation of conventional tillage with mulching alone (CT + M) or together with crop rotation (CT + M + R) resulted in a 20% increase in AMF colonisation of the constantly occurring weed species, Bidens pilosa (BIDPI) and Richardia scabra (RCHSC), com- pared with conventional tillage plus rotations (CT + R). The diversity of AMF was highest under no-tillage plus mulching (NT + M). Off-season and in-season AMF structures of both BIDPI and RCHSC were not related, but 39% of the taxa were shared. Structural equation modelling showed a significant effect of the cropping system on weed AMF diversity parameters and weed and maize root colonisation, but no significant influence of weed root AMF traits and maize colonisation was detected on maize yield. This may be explained by the improvement in weed competitive ability, which may have offset the AMF-mediated benefits on yield. Our findings highlight that implementing M and CR to CT and NT positively affected weed AMF colonisation and diversity. The similarity between the off-season and in-season AMF composition of weeds supports the fact that weeds functionally host AMF during the non-crop period
PALM and STORM : unlocking live-cell super-resolution
Live-cell fluorescence light microscopy has emerged as an important tool in the study of cellular biology. The development of
fluorescent markers in parallel with super-resolution imaging systems has pushed light microscopy into the realm of molecular
visualization at the nanometer scale. Resolutions previously only attained with electron microscopes are now within the grasp of
light microscopes. However, until recently, live-cell imaging approaches have eluded super-resolution microscopy, hampering it
from reaching its full potential for revealing the dynamic interactions in biology occurring at the single molecule level. Here we
examine recent advances in the super-resolution imaging of living cells by reviewing recent breakthroughs in single molecule
localization microscopy methods such as PALM and STORM to achieve this important goal.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-028
A homozygous ADAMTS2 nonsense mutation in a Doberman Pinscher dog with Ehlers Danlos syndrome and extreme skin fragility
An eight-week old Doberman Pinscher was diagnosed with Ehlers Danlos syndrome based on the dog's hyper-mobile carpal, tarsal and stifle joints and abnormal skin. The skin was loose and hyper-elastic with several wounds and large atrophic scars. The dog was euthanized after a severe degloving injury from minimal trauma. A whole-genome sequence, generated with DNA from the dog's blood, contained a rare, homozygous C-to-T transition at position 2408978 on chromosome 11. This transition is predicted to alter the ADAMTS2 transcript (ADAMTS2:c.769C>T) and encode a nonsense mutation (p.Arg257Ter). Biallelic ADAMTS2 mutations have caused a type of Ehlers Danlos syndrome known as dermatosparaxis in other species
Maternal deaths from bleeding associated with caesarean delivery: A national emergency
Maternal deaths associated with caesarean deliveries (CDs) have been increasing in South Africa over the past decade. The objective of this report is to bring national attention to this increasing epidemic of maternal deaths due to bleeding associated with CD in the majority of provinces of the country. Individual chart reviews of women who died from bleeding at or after CD show that 71% had avoidable factors. Among the steps we can take are to improve surgical skills and experience, especially in rural hospitals, to improve clinical observations in the immediate postoperative period and in the postnatal wards, and to ensure that appropriate oxytocic agents are given to prevent postpartum haemorrhage. CEOs and medical managers of health facilities, district clinical specialists, heads of obstetrics and gynaecology, and midwifery training institutions must show leadership and accountability in providing an appropriate environment to ensure that women who require CD receive the procedure for the correct indications and in a safe manner to minimise risks
Maternal deaths from bleeding associated with caesarean delivery: A national emergency
Metabolic biomarkers assessed with PET/CT predict sex-specific longitudinal outcomes in patients with diffuse large B-cell lymphoma
In many cancers, including lymphoma, males have higher incidence and mortality than females. Emerging evidence demonstrates that one mechanism underlying this phenomenon is sex differences in metabolism, both with respect to tumor nutrient consumption and systemic alterations in metabolism, i.e., obesity. We wanted to determine if visceral fat and tumor glucose uptake with fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) could predict sex-dependent outcomes in patients with diffuse large B-cell lymphoma (DLBCL). We conducted a retrospective analysis of 160 patients (84 males; 76 females) with DLBCL who had imaging at initial staging and after completion of therapy. CT-based relative visceral fat area (rVFA), PET-based SUVmax normalized to lean body mass (SULmax), and end-of-treatment FDG-PET 5PS score were calculated. Increased rVFA at initial staging was an independent predictor of poor OS only in females. At the end of therapy, increase in visceral fat was a significant predictor of poor survival only in females. Combining the change in rVFA and 5PS scores identified a subgroup of females with visceral fat gain and high 5PS with exceptionally poor outcomes. These data suggest that visceral fat and tumor FDG uptake can predict outcomes in DLBCL patients in a sex-specific fashion
Baseline characteristics of study sites and women enrolled in a three-arm cluster randomized controlled trial: PMTCT uptake and retention (pure) Malawi
Abstract Background Malawi introduced an ambitious public health program known as âOption B+â which provides all HIV-infected pregnant and breastfeeding women with lifelong combination antiretroviral therapy, regardless of WHO clinical stage or CD4 cell count. The PMTCT Uptake and REtention (PURE) study aimed at evaluating the effect of peer-support on care-seeking and retention in care. Methods/design PURE Malawi was a three-arm cluster randomized controlled trial that compared facility-based and community-based models of peer support to standard of care under Option B+ strategy. Each arm was expected to enroll a minimum of 360 women with a total minimum sample size of 1080 participants. 21 sites (clusters) were selected for inclusion in the study. This paper describes the site selection, recruitment, enrollment process and baseline characteristics of study sites and women enrolled in the trial. Results Study implementation was managed by 3 partner organizations; each responsible for 7 study sites. The trial was conducted in the South East, South West, and Central West zones of Malawi, the zones where the implementing partners operate. Study sites included 2 district hospitals, 2 mission hospitals, 2 rural hospitals, 13 health centers and 1 private clinic. Enrollment occurred from November 2013 to November 2014, over a median period of 31 weeks (range 17â51) by site. A total of 1269 HIV-infected pregnant (1094) and breastfeeding (175) women, who were eligible to initiate ART under Option B+, were enrolled. Each site reached or surpassed the minimum sample size. Comparing the number of women enrolled versus antenatal cohort reports, sites recruited a median of 90% (IQR 75â100) of eligible reported women. In the majority of sites the ratio of pregnant and lactating women enrolled in the study was similar to the ratio of reported pregnant and lactating women starting ART in the same sites. The median age of all women was 27 (IQR 22â31) years. All women have â„20 months of possible follow-up time; 96% â„ 2 years (24â32 months). Conclusion The PURE Malawi study showed that 3 implementing partner organizations could successfully recruit a complex cohort of pregnant and lactating women across 3 geographical zones in Malawi within a reasonable timeline. Trial registration This study is registered at clinicaltrials.gov - ID Number NCT02005835 . Registered 4 December, 2013
Exploiting crop genotype-specific root-soil interactions to enhance agronomic efficiency
Challenges of soil degradation and changing climate pose major threats to food security in many parts of the world, and new approaches are required to close yield and nutrition gaps through enhanced agronomic efficiency. Combined use of mineral fertilizers, organic inputs, improved germplasm and adaptation of these practices to local contexts through improved agronomy can promote efficiency whilst building stocks of soil organic matter (SOM). Within this framework, recent attention has turned to the nature of plant-soil interactions to increase response to mineral fertilizer inputs through utilisation of nutrients from SOM that are replenished through management. This utilisation has been shown in barley and maize to vary with genotype and to be related to root physiological traits associated with rhizodeposition. The identification of candidate genes associated with rhizodeposition takes this a step closer towards the possibility of breeding for sustainability. Here we discuss this potential and feasibility in the context of maize cropping systems, and explore the potential for a combined approach that optimises utilisation of SOM nutrients together with enhanced biological nitrification inhibition to further improve agronomic efficiency
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