691 research outputs found

    Herbaceous Tropical Legume Integration into Small-Holder Crop-Livestock Systems in Eastern Indonesia: Results of 10-Years of Multi-Disciplinary Systems Research

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    Integration a forage legume into crop-livestock systems of Eastern Indonesia was tested to establish the capacity to improve nitrogen supply and yields of staple cereal crops (maize and rice) and allow for intensification of beef production to ultimately increase farm income and alleviate rural poverty in the region. Species evaluation sites across a diversity of environments showed Clitoria ternatea (butterfly pea) to be the most resilient and adaptable forage legume for use in association with cropping systems. Crop rotation experiments demonstrated that legumes grown in rotation with maize or rice can increase grain yields by 50% where legume was cut and removed, and by 90% where legume biomass was retained – the legume providing the equivalent of 100-150 kg of urea fertiliser. Forage establishment and cutting management were shown to be critical to maximising legume productivity but labour inputs required are important constraints. Lower-labour options can be used effectively without dramatically compromising productivity. Providing legumes as supplements to cattle have been shown to have significant benefits for livestock productivity in various production systems; preventing liveweight losses of reproductive cows during the dry season, doubling calf growth rates and halving calf mortality, and increasing growth rates of growing cattle by 0.3-0.5 kg LW/d. Whole-farm bioeconomic modelling and participatory on-farm evaluation has found that livestock-oriented farmers with available land resources will benefit most from forage legumes with potential increases of farm income of up to 30%. Local seed production is critical for ongoing use of herbaceous forage legumes, and our research has refined locally relevant recommendations for agronomy for seed production methods and processing. Our research has confirmed that herbaceous forage legumes can be integrated into cropping systems to improve crop yields, livestock production and livelihoods of small-holder farmers in East Nusa Tenggara, Indonesia

    Optimizing adaptive stepped-care interventions to change adults’ health behaviors: A systematic review

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    Chronic diseases are ubiquitous and costly in American populations. Interventions targeting health behavior change to manage chronic diseases are needed, but previous efforts have fallen short of producing meaningful change on average. Adaptive stepped-care interventions, that tailor treatment based on the needs of the individual over time, are a promising new area in health behavior change. We therefore conducted a systematic review of tests of adaptive stepped-care interventions targeting health behavior changes for adults with chronic diseases. We identified 9 completed studies and 13 research protocols testing adaptive stepped-care interventions for health behavior change. The most common health behaviors targeted were substance use, weight management, and smoking cessation. All identified studies test intermediary tailoring for treatment non-responders via sequential multiple assignment randomized trials (SMARTs) or singly randomized trials (SRTs); none test baseline tailoring. From completed studies, there were few differences between embedded adaptive interventions and minimal differences between those classified as treatment responders and non-responders. In conclusion, updates to this work will be needed as protocols identified here publish results. Future research could explore baseline tailoring variables, apply methods to additional health behaviors and target populations, test tapering interventions for treatment responders, and consider adults’ context when adapting interventions

    eIF4A RNA Helicase Associates with Cyclin-Dependent Protein Kinase A in Proliferating Cells and is Modulated by Phosphorylation

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    Eukaryotic initiation factor 4A (eIF4A) is a highly conserved RNA-stimulated ATPase and helicase involved in the initiation of messenger RNA translation. Previously, we found that eIF4A interacts with cyclin-dependent kinase A (CDKA), the plant ortholog of mammalian CDK1. Here, we show that this interaction occurs only in proliferating cells where the two proteins coassociate with 5â€Č-cap-binding protein complexes, eIF4F or the plant-specific eIFiso4F. CDKA phosphorylates eIF4A on a conserved threonine residue (threonine-164) within the RNA-binding motif 1b TPGR. In vivo, a phospho-null (APGR) variant of the Arabidopsis (Arabidopsis thaliana) eIF4A1 protein retains the ability to functionally complement a mutant (eif4a1) plant line lacking eIF4A1, whereas a phosphomimetic (EPGR) variant fails to complement. The phospho-null variant (APGR) rescues the slow growth rate of roots and rosettes, together with the ovule-abortion and late-flowering phenotypes. In vitro, wild-type recombinant eIF4A1 and its phospho-null variant both support translation in cell-free wheat germ extracts dependent upon eIF4A, but the phosphomimetic variant does not support translation and also was deficient in ATP hydrolysis and helicase activity. These observations suggest a mechanism whereby CDK phosphorylation has the potential to down-regulate eIF4A activity and thereby affect translation

    Risk of Climate-Related Impacts on Global Rangelands – A Review and Modelling Study

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    Climate change threatens the ability of global rangelands to provide food, support livelihoods and deliver important ecosystems services. The extent and magnitude of potential impacts are however poorly understood. In this study, we review the risk of climate impacts along the rangeland systems food supply chain. We also present results from biophysical modelling simulations and spatial data analyses to identify where and to what extent rangelands may be at climatic risk. Although a quantification of the net impacts of climate change on rangeland production systems is beyond the reach of our current understanding, there is strong evidence that there will be impacts throughout the supply chain, from feed and animal production to processing, storage, transport, retailing and human consumption. Regarding grazing biomass production, this study finds that mean herbaceous biomass is projected to decrease across global rangelands between 2000 and 2050 under RCP 8.5 (-4.7%), while inter- (year-to-year) and intra- (month-to-month) annual variabilities are projected to increase (+21.3% and +8.2%, respectively). These averaged global estimates mask large spatial heterogeneities, with 74% of global rangeland area projected to experience a decline in mean biomass, 64% an increase in inter-annual variability and 54% an increase in intra-annual variability. The potentially most damaging vegetation trends for livestock production (i.e., simultaneous decreases in mean biomass and increases in inter-annual variability) are projected to occur in rangeland communities that are currently the most vulnerable (here, with the lowest livestock productivities and economic development levels and with the highest projected increases in human population densities). Large uncertainties remain as to climate futures and the exposure and responses of the interlinked human and natural systems to climatic changes over time. Consequently, adaptation choices will need to build on robust methods of designing, implementing and evaluating detailed development pathways, and account for a wide range of possible futures

    EIFiso4G augments the synthesis of specific plant proteins involved in normal chloroplast function

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    Copyright © 2019 American Society of Plant Biologists. All rights reserved. The plant-specific translation initiation complex eIFiso4F is encoded by three genes in Arabidopsis (Arabidopsis thaliana)-genes encoding the cap binding protein eIFiso4E (eifiso4e) and two isoforms of the large subunit scaffolding protein eIFiso4G (i4g1 and i4g2). To quantitate phenotypic changes, a phenomics platform was used to grow wild-type and mutant plants (i4g1, i4g2, i4e, i4g1 × i4g2, and i4g1 × i4g2 × i4e [i4f]) under various light conditions. Mutants lacking both eIFiso4G isoforms showed the most obvious phenotypic differences from the wild type. Two-dimensional differential gel electrophoresis and mass spectrometry were used to identify changes in protein levels in plants lacking eIFiso4G. Four of the proteins identified as measurably decreased and validated by immunoblot analysis were two light harvesting complex binding proteins 1 and 3, Rubisco activase, and carbonic anhydrase. The observed decreased levels for these proteins were not the direct result of decreased transcription or protein instability. Chlorophyll fluorescence induction experiments indicated altered quinone reduction kinetics for the double and triple mutant plants with significant differences observed for absorbance, trapping, and electron transport. Transmission electron microscopy analysis of the chloroplasts in mutant plants showed impaired grana stacking and increased accumulation of starch granules consistent with some chloroplast proteins being decreased. Rescue of the i4g1 × i4g2 plant growth phenotype and increased expression of the validated proteins to wild-type levels was obtained by overexpression of eIFiso4G1. These data suggest a direct and specialized role for eIFiso4G in the synthesis of a subset of plant proteins

    Decreased fertility rates in 9639 women diagnosed with inflammatory bowel disease: a United Kingdom population-based cohort study

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    Background: Clinical studies have reported reduced fertility in women with inflammatory bowel disease (IBD). Aim: To compare fertility rates in women with IBD to those in women without IBD and assess whether the relative fertility differed following IBD diagnosis, flares and surgery. Methods: Women aged 15-44 years in 1990-2010 were identified from a UK primary care database. We estimated overall and age-specific fertility rates by 5-year age bands for women with and without IBD. We used Poisson regression to calculate adjusted fertility rate ratios (AFRR), adjusted for age, smoking and socioeconomic deprivation. Results: There were 46.2 live births per 1000 person-years [95% confidence interval (95% CI); 44.6-47.9] in 9639 women with IBD and 49.3 (95% CI 49.2-49.5) in 2 131 864 without (AFRR: 0.93; 95% CI: 0.89-0.96). Excluding periods of contraception use, the AFRR was 0.99 (95% CI: 0.95-1.03). Before diagnosis, the AFRR for women with ulcerative colitis (UC) was 1.07 (95% CI: 0.99-1.16) and was 0.88 (95% CI: 0.81-0.97) for women with CD. After diagnosis, AFRRs were 0.87 (95% CI: 0.82-0.94) for CD and 0.92 (95% CI: 0.86-1.00) for UC. The fertility rate was lower following flares (AFRR: 0.70; 95% CI: 0.59-0.82) or surgery (AFRR: 0.84; 95% CI: 0.77-0.92). Women with pouch and non-pouch surgery had similar overall fertility though the reduction after surgery was greater for pouches (AFRR: 0.48; 95% CI: 0.23-0.99). Conclusions: Women with Crohn's disease have marginally lower fertility rates. These rates decreased following flares and surgical interventions. Fertility rates returned almost to normal when women were not prescribed contraception but the reduction following surgical intervention remained. As the lifetime effect of pouch vs. nonpouch surgery on fertility is small, the reduction post-pouch surgery should be interpreted with caution

    Exact solution of a two-type branching process: Clone size distribution in cell division kinetics

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    We study a two-type branching process which provides excellent description of experimental data on cell dynamics in skin tissue (Clayton et al., 2007). The model involves only a single type of progenitor cell, and does not require support from a self-renewed population of stem cells. The progenitor cells divide and may differentiate into post-mitotic cells. We derive an exact solution of this model in terms of generating functions for the total number of cells, and for the number of cells of different types. We also deduce large time asymptotic behaviors drawing on our exact results, and on an independent diffusion approximation.Comment: 16 page
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