478 research outputs found
Multi-environment QTL mixed models for drought stress adaptation in wheat
Many quantitative trait loci (QTL) detection methods ignore QTL-by-environment interaction (QEI) and are limited in accommodation of error and environment-specific variance. This paper outlines a mixed model approach using a recombinant inbred spring wheat population grown in six drought stress trials. Genotype estimates for yield, anthesis date and height were calculated using the best design and spatial effects model for each trial. Parsimonious factor analytic models best captured the variance-covariance structure, including genetic correlations, among environments. The 1RS.1BL rye chromosome translocation (from one parent) which decreased progeny yield by 13.8 g m(-2) was explicitly included in the QTL model. Simple interval mapping (SIM) was used in a genome-wide scan for significant QTL, where QTL effects were fitted as fixed environment-specific effects. All significant environment-specific QTL were subsequently included in a multi-QTL model and evaluated for main and QEI effects with non-significant QEI effects being dropped. QTL effects (either consistent or environment-specific) included eight yield, four anthesis, and six height QTL. One yield QTL co-located (or was linked) to an anthesis QTL, while another co-located with a height QTL. In the final multi-QTL model, only one QTL for yield (6 g m(-2)) was consistent across environments (no QEI), while the remaining QTL had significant QEI effects (average size per environment of 5.1 g m(-2)). Compared to single trial analyses, the described framework allowed explicit modelling and detection of QEI effects and incorporation of additional classification information about genotypes
Vitamin K status, supplementation and vascular disease: a systematic review and meta-analysis
Objectives: Vascular stiffness (VS) and vascular calcification (VC) are surrogate markers of vascular health associated with cardiovascular events. Vitamin K-dependent proteins (VKDP) are associated with VS and VC and require vitamin K for activity. We conducted a systematic review and meta-analysis of: (1) the effect of vitamin K supplementation on VS and VC and (2) association of inactive VKDP levels with incident cardiovascular disease and mortality.
Methods: Two authors searched MEDLINE and Embase databases and Cochrane and ISRCTN registries for studies of vitamin K clinical trials that measured effects on VC, VS or VKDP and longitudinal studies assessing effect of VKDP on incident CVD or mortality. Random effects meta-analyses were performed.
Results: Thirteen controlled clinical trials (n=2162) and 14 longitudinal studies (n=10â726) met prespecified inclusion criteria. Vitamin K supplementation was associated with significant reduction in VC (â9.1% (95% CI â17.7 to â0.5); p=0.04) and VKDP (desphospho-uncarboxylated matrix Gla protein; â44.7% (95% CI â65.1 to â24.3), p<0.0001) and uncarboxylated osteocalcin; â12.0% (95% CI â16.7 to â7.2), p<0.0001) compared with control, with a non-significant improvement in VS. In longitudinal studies with median follow-up of 7.8 (IQR 4.9â11.3)âyears, VKDP levels were associated with a combined endpoint of CVD or mortality (HR 0.45 (95% CI 0.07 to 0.83), p=0.02).
Conclusions: Supplementation with vitamin K significantly reduced VC, but not VS, compared with control. The conclusions drawn are limited by small numbers of studies with substantial heterogeneity. VKDP was associated with combined endpoint of CVD or mortality. Larger clinical trials of effect of vitamin K supplementation to improve VC, VS and long-term cardiovascular health are warranted.
Trial registration number: CRD42017060344
The global build-up to intrinsic ELM bursts and comparison with pellet triggered ELMs seen in JET
We focus on JET plasmas in which ELMs are triggered by pellets in the presence of ELMs
which occur naturally. We perform direct time domain analysis of signals from fast radial
field coils and toroidal full flux azimuthal loops. These toroidally integrating signals provide
simultaneous high time resolution measurements of global plasma dynamics and its coupling
to the control system. We examine the time dynamics of these signals in plasmas where pellet
injection is used to trigger ELMs in the presence of naturally occurring ELMs. Pellets whose
size and speed are intended to provide maximum local perturbation for ELM triggering are
launched at pre-programmed times, without correlation to the occurrence times of intrinsic
ELMs. Pellet rates were sufficiently low to prevent sustained changes of the underlying
plasma conditions and natural ELM behaviour. We find a global signature of the build-up to
natural ELMs in the temporal analytic phase of both the full flux loops and fast radial field
coil signals. Before a natural ELM, the signal phases align to the same value on a âź2â5ms
timescale. This global build up to a natural ELM occurs whilst the amplitude of the full flux
loop and fast radial field coil signals are at their background value: it precedes the response
seen in these signals to the onset of ELMing. In contrast these signals do not clearly phase
align before the ELM for ELMs which are the first to occur following pellet injection. This
provides a direct test that can distinguish when an ELM is triggered by a pellet as opposed to
occurring naturally. It further supports the idea [1â4] of a global build up phase that precedes
natural ELMs; pellets can trigger ELMs even when the signal phase is at a value when a
natural ELM is unlikely to occurEURATOM 633053ONR NICOP N62909-15-1-N14
Towards a collaborative, global infrastructure for biodiversity assessment
Biodiversity data are rapidly becoming available over the Internet in common formats that promote sharing and exchange. Currently, these data are somewhat problematic, primarily with regard to geographic and taxonomic accuracy, for use in ecological research, natural resources management and conservation decision-making. However, web-based georeferencing tools that utilize best practices and gazetteer databases can be employed to improve geographic data. Taxonomic data quality can be improved through web-enabled valid taxon names databases and services, as well as more efficient mechanisms to return systematic research results and taxonomic misidentification rates back to the biodiversity community. Both of these are under construction. A separate but related challenge will be developing web-based visualization and analysis tools for tracking biodiversity change. Our aim was to discuss how such tools, combined with data of enhanced quality, will help transform today's portals to raw biodiversity data into nexuses of collaborative creation and sharing of biodiversity knowledge
Estimation method for determining surface film conductance during cooling of fish packages.
This paper presents an alternative method for determining the surface film conductance of an infinite fish slab subjected to the cooling process. Many methods have been published, but their solutions have inherent appreciable inaccuracy and limitations. The present authors used the temperature histories of five locations within a slab sample of fish, obtained by the experimental investigation part of this work, along with the inverse heat conduction problem (IHCP) technique to develop a correlation for variable surface film conductance. When the above correlation was used for temperature predictions, the predicted and experimentally measured temperature distribution profiles were compared numerically. Better agreement than that implemented by other investigators was achieved. This revealed the accuracy and superiority of the present method, and the limitations of other methods are overcome in this method
NitrogĂŞnio e enxofre na adubação e em folhas diagnĂłsticas e raĂzes do capimbraquiĂĄria em degradação
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Achievements and Challenges in the Science of Space Weather
In June 2016 a group of 40 space weather scientists attended the workshop on Scientific Foundations of Space Weather at the International Space Science Institute in Bern. In this lead article to the volume based on the talks and discussions during the workshop we review some of main past achievements in the field and outline some of the challenges that the science of space weather is facing today and in the future.Peer reviewe
NitrogĂŞnio e enxofre nas caracterĂsticas morfogĂŞnicas do capim-marandu em substituição ao capim-braquiĂĄria em degradação em solo com baixo teor de matĂŠria orgânica
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