Root system traits and its relationship with photosynthesis and productivity in four maize genotypes under drought

The present study combined evaluations of agronomic parameters such as roots morphometry (using the WinRhizo program) and leaf gas exchange, in order to detect features in the root system which allow the maintenance of photosynthetic rates and productivity in four maize genotypes contrasting for tolerance to water deficit (WD), two tolerant (DKB 390 and BRS1055) and two sensitive (BRS 1010 and 2B710). The genotypes showed similar tolerance to dehydration of leaf tissue, but the tolerant genotypes DKB 390 and BRS1055 presented higher photosynthetic rate and yield compared to the sensitive BRS 1010 and 2B710. Nevertheless, divergent strategies of adaptation to drought among tolerant genotypes were observed. The genotype DKB 390 presented physiological mechanisms in shoots responsible for minimizing water loss, which decreases the dependence of root adjustments to increase the absorption of water. In turn, the BRS 1055 genotype showed a drought avoidance strategy by producing fine roots associated with a higher leaf area

Improving the analytical assessment of fish stocks by providing parameters of data quality via InterCatch

The last multiannual Community program for the collection, management and use of data in the fisheries sector (Commission Decision 2008/949/EC) stated the provision of precision levels and sampling intensities of the estimates at national level. However, the unequal compliance of this standard has hindered its application in stock assessment and the consequent scientific advice. The cost-benefit analysis of a sampling program, besides addressing logistical and economic constraints, should deepen the potential of the tools currently available. This article proposes to test the calculation, provision and use in stock assessment of extensively collected precision parameters. First, sampling intensities and coefficients of variation of fisheries-dependent parameters are calculated using the COST software, a statistical tool specifically designed to quantify uncertainty in marine sampled data. Secondly, alternative ways are explored to provide precision parameters to the stock assessment coordinators by using InterCatch, the existing ICES web-based system to submit national data and compile international catch matrices. Finally, the incorporation of these precision parameters in the assessment model is tested, through a stock assessed by statistical assessment models (such as SS3) which can account for sampling errors. Thus, it will be possible to quantify how errors in input data propagate through stock assessment models to affect harvest rules, and also to help identify the most cost-effective data collections that adequately support the advisory process

Analysis of the small-scale fleet’s coverage under two sampling strategies: from the DCR stock-based to the DCF concurrent sampling in the Northern Spanish coastal gillnets fleet

Working document presented at the WGCATCH 2015 meeting.The Northern Spanish coastal small scale fleet represents a major challenge for sampling due to the multi-species and multi-gear character and the complexity of the fleets’ dynamics. Particularly, the small-scale gillnets called “beta” (GNS_DEF_60-79_0_0) represents a complex Spanish métiers in terms of catches, effort, geographical distribution and the number of exploited species. Comparison of data obtained in 2008, under a stock-based approach, versus concurrent sampling realized in 2014 resulted in the increase of the information obtained and provided to ICES without detected failures in data quality. Concurrent sampling could represent a source of information for small-scale fisheries which often target a set of coastal species some of which are presently unassesed

The Fermi Liquid as a Renormalization Group Fixed Point: the Role of Interference in the Landau Channel

We apply the finite-temperature renormalization-group (RG) to a model based on an effective action with a short-range repulsive interaction and a rotation invariant Fermi surface. The basic quantities of Fermi liquid theory, the Landau function and the scattering vertex, are calculated as fixed points of the RG flow in terms of the effective action's interaction function. The classic derivations of Fermi liquid theory, which apply the Bethe-Salpeter equation and amount to summing direct particle-hole ladder diagrams, neglect the zero-angle singularity in the exchange particle-hole loop. As a consequence, the antisymmetry of the forward scattering vertex is not guaranteed and the amplitude sum rule must be imposed by hand on the components of the Landau function. We show that the strong interference of the direct and exchange processes of particle-hole scattering near zero angle invalidates the ladder approximation in this region, resulting in temperature-dependent narrow-angle anomalies in the Landau function and scattering vertex. In this RG approach the Pauli principle is automatically satisfied. The consequences of the RG corrections on Fermi liquid theory are discussed. In particular, we show that the amplitude sum rule is not valid.Comment: 25 pages, RevTeX 3.

Evaluation of Sedentary Behavior and Physical Activity Levels Using Different Accelerometry Protocols in Children from the GENOBOX Study

Background Physical activity (PA) has acquired a significant relevance due to the health benefits associated with its practice. Accelerometers are an effective tool to assess PA; however, the diversity of cut-off points used to define different PA intensities through accelerometry could interfere in the interpretation of the findings among studies. Objectives The present study aimed to examine the sedentary behavior (SB) and physical activity (PA) levels in children using six selected accelerometry protocols based on diverse cut-off points. Methods Clinical examination, anthropometric measurements, and PA evaluation by accelerometry were assessed in 543 selected children (10 +/- 2.4 years old) from the Spanish GENOBOX study. The ActiLife data scoring program was used to determine daily min spent in SB, and light, moderate, vigorous and moderate-vigorous PA using six validated accelerometry protocols differing in their cut-off points. Results Very different estimations for SB and PA intensity levels were found in children, independently of the non-wear-time algorithm selected, and considering puberty stages, age and body mass index. The time spent in daily SB varied from 471 to 663.7 min, PA ranged from 141 to 301.6 min, and the moderate-vigorous PA was reported between 20.7 and 180.2 min. Conclusion The choice of a particular accelerometry protocol considering these factors is important to evaluate SB or PA intensities to suit the characteristics of the sample researched. It seems necessary to establish future lines of research that include different analytical approaches to measure SB and PA by accelerometry based on standardized and validated methodology

Rare charm meson decays D->Pl^+l^- and c->ul^+l^- in SM and MSSM

We study the nine possible rare charm meson decays D->Pl^+l^- (P=pi,K,eta,eta') using the Heavy Meson Chiral Lagrangians and find them to be dominated by the long distance contributions. The decay D^+ -> pi^+l^+l^- with the branching ratio 1*10^(-6) is expected to have the best chances for an early experimental discovery. The short distance contribution in the five Cabibbo suppressed channels arises via the c->ul^+l^- transition; we find that this contribution is detectable only in the D->pi l^+l^- decay, where it dominates the differential spectrum at high-q^2. The general Minimal Supersymmetric Standard Model can enhance the c->ul^+l^- rate by up to an order of magnitude; its effect on the D->Pl^+l^- rates is small since the c->ul^+l^- enhancement is sizable in low-q^2 region, which is inhibited in the hadronic decay.Comment: 17 page