118 research outputs found
Participatory Multi-Environmental Trials (MET) identified promising durum wheat landraces in Northern Ethiopia
Participation of farmers in research process from early stage has been gaining ground in breeding research. Participant farmers can provide very valuable scientific evaluation of genotypes that can be used for effective discrimination of useful varieties easily adopted by similar farmers. Participatory varietal selection (PVS) is a powerful tool in identifying crops varieties with high acceptance probability in marginal environments because participant farmers evaluate the genotypes not only from yield perspective but also from stress tolerance perspective. Here we present a participatory MET conducted in four locations to select durum wheat landraces for larger scale production in the areas. In all four locations, 36 genotypes (31 landraces plus 5 improved varieties) were tested for two cropping seasons and evaluated by both researchers and farmers groups. In each location, a total of 30 farmers (15 female and 15 male) and five breeders critically evaluated the each variety for earliness, spike quality, drought tolerance and overall performance on scale of 1 to 5, traits defined by the farmers themselves. 1 stands for bad and 5 for excellent performance. Researchers have collected data for three phenological traits and seven agronomic traits and analysis was conducted to see preference matching between researcher data and farmers score data.
The results show clearly that farmers are capable to discriminate genotypes reasonably though their discrimination power varies from location to location. The discrimination by breeders was consistent across locations. Very high significant (p<0.01) association was established between farmers visual score and researchers collected grain yield data and days to maturity in all locations with some exceptions for maturity date. Genotypes ranking for grain yield based on researchers collected data and farmer scoring matched about 80% in the 10 top performing genotypes.
In conclusion:
· Participatory varietal selection could bridge the problem of variety adoption by complementing farmers and breeders preferences .
· Farmers are keen in evaluating genotypes and have reasons for rejecting or accepting varieties .
· There was good agreement between farmers score and objectively collected data in identifying the 10 top performing genotypes.
Participatory MET could be a reliable approach for fast technology development and dissemination as it considers the involvement of end users from the very beginning
Stimulated bioremediation of soil contaminated with spent engine oil using organic wastes
In this study, the role of some organic wastes in stimulating the removal of petroleum hydrocarbon from contaminated soil was assessed. The concentration of hydrocarbon in soil before, during and after bioremediation and volume of carbon dioxide released from soil were investigated. The contaminated soil was amended with chicken droppings (CD), cow dung (CDU), and rice husk (RH) for sixty (60) days under laboratory conditions. The soil was mixed thoroughly every ten (10) days to enhance aeration, and 60% water holding capacity (WHC) of the soil was maintained to supply bacteria with adequate moisture. The initial pH value of soil was 4.7, while CD, CDU and RH had values of 6.9, 7.1 and 7.6 respectively. Water holding capacity (WHC) of contaminated soil was 15%, CD showed 31%, CDU (43%) while RH had 40.7%.The percentage of nitrogen in soil was very low (0.92%) compared to Organic carbon (10.5%), and Phosphorous (19.2mg/kg).CD showed the highest value of nitrogen (2.4%) and phosphorous (17.6mg/kg) followed by CDU with 1.7%;17.1mg/kg and 0.89%;15.21mg/kg in RH. Highest concentration of organic carbon (11.4%) was recorded in RH; CDU had 10.9% while CD was with 10.1%. Concentration of spent engine oil in soil before bioremediation was 7.525mg/g. The initial count of Hydrocarbon degrading Bacteria (HDB) in contaminated soil was 5.7x105CFU/g, and species of HDB isolated from soil were Acinetobacter, Bacillus, Micrococcus, Flavobacterium, and Pseudomonas. Total petroleum hydrocarbon in soil amended with CD was reduced by 86.7%, CDU and RH treated soils showed 80.05% and 66.75% reduction respectively, while untreated soil recorded lowest reduction (46.8%) at the end of 60days period. Largest volume of carbon dioxide was evolved from soil amended with CD (15.77cm-3).Soil treated with CDU produced 14.02cm-3, and RH soil had 11.72cm-3. Lowest volume (3.78cm-3) of carbon dioxide was produced from untreated soil. This result demonstrated that these organic wastes could stimulate biodegradation of spent engine oil in the order CD>CDU>RH
Incidence of Fungal flora and Aflatoxin content of millet and maize cereal grains sold in Guinea savanna zones of Kebbi State
Cereal grains get contaminated with fungi and aflatoxin due to poor agricultural, displayed in market and storage practices. A total of three local governments in Guinea savanna zone of Kebbi State were selected for samples collection namely; Zuru, Yauri and Danko/Wasgu. Five heads of millet and five heads of maize were collected in each site, marked total of Thirty (30) head of both millet and maize in all. Fungi were isolated on Potato Dextrose Agar (PDA) using Agar plate method. Eight (8) fugal species were isolated and identified as Aspergillus flavus, Aspergillus fumigates, Fusarium spp., Aspergillus niger, Rhizopus stolonifer, Mucor hiemalis, Eurotium harvarium and Penicillium spp. The highest incidence of fungi were obtained in Aspergillus flavus with (30.9%) and lowest were obtained in Eurotium harvarium (4.4%). Enzyme-linked immunosorbent Assay (ELISA) were used for the determination of Aflatoxin. From the results obtained Zuru had the highest level of aflatoxin 58.00±3.65a μg/kg in millet while Danko/Wsagu with less 12.72±2.99bμg/kg in maize. Implication of this findings showed that both millet and maize had aflatoxin levels above maximum acceptable limit of 10μg/kg set EU and NAFDAC. Therefore, adequate and rapid drying of grains to water content level may be employed as this could reduce the growth of aflatoxingenic fungi to the minimum possible level
Crop variety management for climate adaptation supported by citizen science
Crop adaptation to climate change requires accelerated crop variety introduction accompanied by recommendations to help
farmers match the best variety with their field contexts. Existing approaches to generate these recommendations lack scalability and predictivity in marginal production environments. We tested if crowdsourced citizen science can address this challenge, producing empirical data across geographic space that, in aggregate, can characterize varietal climatic responses. We present the results of 12,409 farmer-managed experimental plots of common bean (Phaseolus vulgaris L.) in Nicaragua, durum wheat (Triticum durum Desf.) in Ethiopia, and bread wheat (Triticum aestivum
L.) in India. Farmers collaborated as citizen scientists, each ranking the performance of three varieties randomly assigned from a
larger set. We show that the approach can register known specific effects of climate variation on varietal performance. The prediction of variety performance from seasonal climatic variables was generalizable across growing seasons. We show that these analyses can improve variety recommendations in four aspects: reduction of climate bias, incorporation of seasonal climate forecasts, risk analysis, and geographic extrapolation. Variety recommendations derived from the citizen science trials led to important differences with previous recommendations
Risk Factors for Revision of Polished Taper-Slip Cemented Stems for Periprosthetic Femoral Fracture After Primary Total Hip Replacement: A Registry-Based Cohort Study from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man
Background: Total hip replacement (THR) with a cemented polished taper-slip (PTS) femoral stem has excellent long-term results but is associated with a higher postoperative periprosthetic femoral fracture (PFF) risk compared with composite beam stems. This study aimed to identify risk factors associated with PFF revision following THR with PTS stems.
Methods: In a retrospective cohort study, 299,019 primary THRs using PTS stems from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR) were included, with a median follow-up of 5.2 years (interquartile range [IQR], 3.1 to 8.2 years). The adjusted hazard ratio (HR) of PFF revision was estimated for each variable using multivariable Cox survival regression analysis.
Results: Of 299,019 THR cases, 1,055 underwent revision for PFF at a median time of 3.1 years (IQR, 1.0 to 6.1 years). The mean age (and standard deviation) was 72 ± 9.7 years, 64.3% (192,365 patients) were female, and 82.6% (247,126 patients) had an American Society of Anesthesiologists (ASA) class of 1 or 2. Variables associated with increased PFF were increasing age (HR, 1.02 per year), intraoperative fracture (HR, 2.57 [95% confidence interval (CI), 1.42 to 4.66]), ovaloid (HR, 1.96 [95% CI, 1.22 to 3.16]) and round cross-sectional shapes (HR, 9.58 [95% CI, 2.29 to 40.12]), increasing stem offset (HR, 1.07 per millimeter), increasing head size (HR, 1.04 per millimeter), THR performed from 2012 to 2016 (HR, 1.45 [95% CI, 1.18 to 1.78]), cobalt-chromium stem material (HR, 6.7 [95% CI, 3.0 to 15.4]), and cobalt-chromium stems with low-viscosity cement (HR, 22.88 [95% CI, 9.90 to 52.85]). Variables associated with a decreased risk of PFF revision were female sex (HR, 0.52 [95% CI, 0.45 to 0.59]), increasing stem length (HR, 0.97 per millimeter), and a ceramic-on-polyethylene bearing (HR, 0.55 [95% CI, 0.36 to 0.85]).
Conclusions: Increased risk of PFF revision was associated with PTS stems that are short, have high offset, are used with large femoral heads, are made of cobalt-chromium, or have ovaloid or round cross-sectional shapes. Large increases in PFF risk were associated with cobalt-chromium stems used with low-viscosity cement. Further study is required to confirm causation.
Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence
Search for leptophobic Z ' bosons decaying into four-lepton final states in proton-proton collisions at root s=8 TeV
Peer reviewe
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at √NN = 5.02 TeV
The second-order Fourier coefficients (υ) characterizing the azimuthal distributions of Υ(1S) and Υ(2S) mesons produced in PbPb collisions at = 5.02 TeV are studied. The Υmesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb. The scalar product method is used to extract the υ coefficients of the azimuthal distributions. Results are reported for the rapidity range |y| < 2.4, in the transverse momentum interval 0 < p < 50 GeV/c, and in three centrality ranges of 10–30%, 30–50% and 50–90%. In contrast to the J/ψ mesons, the measured υ values for the Υ mesons are found to be consistent with zero
Phenomenological MSSM interpretation of CMS searches in pp collisions at √s=7 and 8 TeV
Searches for new physics by the CMS collaboration are interpreted in the framework of the phenomenological minimal supersymmetric standard model (pMSSM). The data samples used in this study were collected at root s = 7 and 8 TeV and have integrated luminosities of 5.0 fb(-1) and 19.5 fb(-1), respectively. A global Bayesian analysis is performed, incorporating results from a broad range of CMS supersymmetry searches, as well as constraints from other experiments. Because the pMSSM incorporates several well-motivated assumptions that reduce the 120 parameters of the MSSM to just 19 parameters defined at the electroweak scale, it is possible to assess the results of the study in a relatively straightforward way. Approximately half of the model points in a potentially accessible subspace of the pMSSM are excluded, including all pMSSM model points with a gluino mass below 500 GeV, as well as models with a squark mass less than 300 GeV. Models with chargino and neutralino masses below 200 GeV are disfavored, but no mass range of model points can be ruled out based on the analyses considered. The nonexcluded regions in the pMSSM parameter space are characterized in terms of physical processes and key observables, and implications for future searches are discussed
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