Background. Estimation of animal body weight (BW) is a fundamental tool in herd management for the development of reproductive, nutritional and health programmes. Objective. To compare the actual BW ...and its estimation by visual method and measurement of the heart girth (HG) or hip width (HW) for estimating BW in crossbred beef heifers reared under humid tropical conditions in Mexico. Methodology. Data on GH, HW, BW estimated by the visual method (MV) and actual BW were recorded in 105 crossbred replacement heifers (Bos taurus × Bos indicus) Swiss American, Beef Master, Simmental, and Brahman with different degrees of crossbreeding. Heifers ranged in age from three to 20 months and were grazed on star grass (Cynodon nlemfuensis) and humidicola grass (Brachiaria humidicola) pastures without supplementation. BW was recorded using a digital scale, HG was measured using a flexible fibreglass tape and HW was measured using a 65 cm forceps. BW by visual estimation was considered as the average of three observations made by three observers, HG and HW methods using the formula 1) BW (kg): 202.68 - 4.39 × HG + 0.03 × HG2; 2) BW (kg): 0.26 × HW1.90. The Pearson coefficient and the distribution (density) of each variable, were assessed using a correlation matrix graph. Also, a comparison the measures obtained by each of the different estimation methods with the observed weights, by inspecting the paired Bland-Altman plots, prior to logarithmic transformation. Results. Correlations between observed BW and predicted BW for the HG, HW and visual methods showed a positive and significant relationship (P<0.001), with r values of 0.95, 0.89 and 0.92, respectively. The HG method tended to overestimate the real BW, whereas, in the visual and HW methods, the values are evenly and randomly distributed around the line, indicating that these methods neither underestimated nor overestimated the BW. Implications. Although the HG method showed the highest correlation coefficient between observed and predicted BW, the result of the present study showed that visual assessment highlights the ability of observers to visually estimate the BW of growing heifers. Conclusion. Livestock handlers have a very accurate estimation of BW. The use of alternative methods to scales, such as the HG measuring method, can be useful and practical tools to improve the accuracy of the assessment.
Honey bee (Apis mellifera) colonies of African and European descent were compared for levels of Varroa destructor infestation in 3 different ecological regions in Mexico. The 300 colonies that were ...studied were located in subtropical, temperate sub-humid, and temperate dry climates. The morphotype and mitotype of adult bees as well as their rates of infestation by varroa mites were determined. Additionally, the number of combs with brood and covered with bees was recorded for each colony. The highest frequency of colonies that were classified as African-derived was found in the subtropical environment, whereas the lowest occurred in the temperate dry region. Overall, the colonies of African genotype had significantly lower mite infestation rates (3.5±0.34%) than the colonies of European genotype (4.7±0.49%) regardless of the region sampled. Significant effects of genotype and region on Varroa infestation rates were evident, and there were no differences in bee population or capped brood between genotypes. Mite infestation levels were significantly lower in the colonies of the temperate dry region than in the colonies of the other 2 regions. These results are discussed within the context of results from studies that were previously conducted in Brazil. This is the first study that demonstrates the effects of Africanization and ecological environment on V. destructor infestation rates in honey bee colonies in North America.
The authors study the production of very-high-energy emission in blazars as a superposition of a steady component from a baryonic jet and a time-dependent contribution from an inner e super( -)e ...sigma up + beam launched by the black hole. Both primary relativistic electrons and protons are injected in the jet, and the particle distributions along it are found by solving a one-dimensional transport equation that accounts for convection and cooling. The short-timescale variability of the emission is explained by local pair injections in turbulent regions of the inner beam. For illustration, the authors apply the model to the case of PKS2155-304, reproducing a quiescent state of emission with inverse Compton and synchrotron radiation from primary electrons, as well as proton-proton interactions in the jet. The latter also yield an accompanying neutrino flux that could be observed with a new generation km-scale detector in the northern hemisphere such as KM3NeT.
Gadolinium-based contrast agents are widely used to enhance image contrast in magnetic resonance imaging (MRI) procedures. Over recent years, there has been a renewed interest in the physicochemical ...properties of gadolinium chelates used as contrast agents for MRI procedures, as it has been suggested that dechelation of these molecules could be involved in the mechanism of a recently described disease, namely nephrogenic systemic fibrosis (NSF). The aim of this paper is to discuss the structure-physicochemical properties relationships of marketed gadolinium chelates in regards to their biological consequences. Marketed gadolinium chelates can be classified according to key molecular design parameters: (a) nature of the chelating moiety: macrocyclic molecules in which Gd³⁺ is caged in the pre-organized cavity of the ligand, or linear open-chain molecules, (b) ionicity: the ionicity of the complex varies from neutral to tri-anionic agents, and (c) the presence or absence of an aromatic lipophilic residue responsible for protein binding. All these molecular characteristics have a profound impact on the physicochemical characteristics of the pharmaceutical solution such as osmolality, viscosity but also on their efficiency in relaxing water protons (relaxivity) and their biodistribution. These key molecular parameters can also explain why gadolinium chelates differ in terms of their thermodynamic stability constants and kinetic stability, as demonstrated by numerous in vitro and in vivo studies, resulting in various formulations of pharmaceutical solutions of marketed contrast agents. The concept of kinetic and thermodynamic stability is critically discussed as it remains a somewhat controversial topic, especially in predicting the amount of free gadolinium which may result from dechelation of chelates in physiological or pathological situations. A high kinetic stability provided by the macrocyclic structure combined with a high thermodynamic stability (reinforced by ionicity for macrocyclic chelates) will minimize the amount of free gadolinium released in tissue parenchymas.
As a follow-up to the GPR40 agonist AMG 837, which was evaluated in clinical trials for the treatment of type II diabetes, further optimization led to the discovery of AM-3189 (13k). AM-3189 is ...representative of a new class of compounds with minimal CNS penetration, superior pharmacokinetic properties and comparable in vivo efficacy. Display omitted
As a follow-up to the GPR40 agonist AMG 837, which was evaluated in clinical trials for the treatment of type II diabetes, further optimization led to the discovery of AM-3189 (13k). AM-3189 is representative of a new class of compounds with minimal CNS penetration, superior pharmacokinetic properties and in vivo efficacy comparable to AMG 837.
The study presented here shows a method based on network theory to identify the most important journals related to a given journal, the seed journal. In just one simple network map, we get the ...relevant citation environment of a specific seed journal. It is of interest to librarians, publishers, scientists and science policy makers. These journal citation network maps are useful for these various stakeholders in and around the science system, as they provide information on the level of journal connections, unlike the more traditional structures such as the Journal Subject Categories, the classification system applied in the products of Thomson Reuters (Journal Citation Reports, Web of Science, etc.). These network maps show the closest relations journals can have, based on citation relations, suggesting influence relations between journals in such a way that traditional field boundaries are transcended.
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2,3,4-Substituted quinolines such as (10a) were found to be potent inhibitors of PI3Kδ in both biochemical and cellular assays with good selectivity over three other class I PI3K ...isoforms. Some of those analogs showed favorable pharmacokinetic properties.▪
This paper introduces a novel single channel speech enhancement method in the time domain to mitigate the effects of acoustic impulsive noises. The ensemble empirical mode decomposition is applied to ...analyze the noisy speech signal. The estimation and selection of noise components is based on the impulsiveness index of decomposition modes. An adaptive threshold is proposed to define the criterion to select the noise components. The proposed method is evaluated in speech enhancement experiments considering four acoustic noises with different impulsiveness indices and non-stationarity degrees under various signal-to-noise ratios. Four speech enhancement algorithms are adopted as baseline in the evaluation analysis considering spectral and time domains. Seven objective measures are adopted to compare the proposed and baseline approaches in terms of speech quality and intelligibility. Results show that the proposed solution outperforms the competing algorithms for most of the noisy scenarios. The novel method shows particularly interesting performance when speech signals are corrupted by highly impulsive acoustic noises.
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