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Nutritional composition of browse and diets fed to ungulates at the Breeding Centre for Endangered Arabian Wildlife
Captive browsing ruminants are particularly susceptible to gastrointestinal disorders, and inappropriate diets are an underlying factor. This study investigated the nutritional composition of browse and pelleted feedstuffs used in an Arabian facility and compared nutrient intake against current recommendations for exotic ungulates. Additionally, retrospective evaluation of post-mortem findings with regard to gastrointestinal pathologies was conducted (n = 497). Samples of browse from seven species of locally cultivated plants, as well as three brands of pelleted feeds, were submitted for laboratory analysis. Following a five-day feed intake study, nutrient intake was calculated. Only moderate variation was seen among browse species’ composition compared to previous reports. However, significant variation occurred between plant fractions (stem, leaves and seed pods) for neutral detergent fibre and several minerals. Browse comprised over half of the metabolisable energy (ME) intake of Arabian tahr (rabitragus jayakari), but only 11% of ME for Arabian gazelle (Gazella gazella cora) and Dorcas gazelle (G. gazella dorcas). However, no relationship could be detected between gastrointestinal disease and browse provision in these species. No nutrient deficiencies were identified, but the Arabian tahr diet exceeded the recommended amount of crude protein, and both gazelle diets provided excess iron, manganese, copper and zinc. These mineral excesses are the subject of on-going investigations in order to better balance the diets offered. Moreover, the high starch content of pelleted diets evaluated in the current study (22-29%, on a dry matter basis) indicates that a reduction in the proportional provision of pellets would improve the diet suitability, particularly for the gazelles. This study highlights a number of areas for potential improvement, although further research is required to fully understand the implications of these findings
Haemangiosarcoma in a captive Asiatic lion (Panthera leo persica)
A 2.7-year-old male captive Asiatic lion (Panthera leo persica) died unexpectedly without preceding symptoms. Gross necropsy revealed liver and lung tumours, which proved to be haemangiosarcomas by histopathology. Some of the liver tumours were ruptured, leading to massive intra-abdominal haemorrhage and death. Haemangiosarcomas are rare in domestic and exotic felids, occurring in skin, thoracic-abdominal cavity and bones. Although these tumours mainly appear to be occurring in older cats, they are sometimes observed in younger animals, as in the present case. This is the first description of haemangiosarcoma in a young Asiatic lion
Abnormal connectivity between attentional, language and auditory networks in schizophrenia
Brain circuits involved in language processing have been suggested to be compromised in patients with schizophrenia. This does not only include regions subserving language production and perception, but also auditory processing and attention. We investigated resting state network connectivity of auditory, language and attention networks of patients with schizophrenia and hypothesized that patients would show reduced connectivity. Patients with schizophrenia (n=45) and healthy controls (n=30) underwent a resting state fMRI scan. Independent components analysis was used to identify networks of the auditory cortex, left inferior frontal language regions and the anterior cingulate region, associated with attention. The time courses of the components where correlated with each other, the correlations were transformed by a Fisher's Z transformation, and compared between groups. In patients with schizophrenia, we observed decreased connectivity between the auditory and language networks. Conversely, patients showed increased connectivity between the attention and language network compared to controls. There was no relationship with severity of symptoms such as auditory hallucinations. The decreased connectivity between auditory and language processing areas observed in schizophrenia patients is consistent with earlier research and may underlie language processing difficulties. Altered anterior cingulate connectivity in patients may be a correlate of habitual suppression of unintended speech, or of excessive attention to internally generated speech. This altered connectivity pattern appears to be present independent of symptom severity, and may be suggestive of a trait, rather than a state characteristic. (C) 2011 Elsevier B.V. All rights reserved
ABRASIVE WEAR BY TiO 2 ON HARD AND LOW FRICTION COATINGS
ABSTRACT Several components in paint and plastic industry, like mixers, extrusion screws and dies, injection moulds, suffer heavily from abrasive wear. This wear is mainly induced by the presence of TiO 2 in the paint or in the plastic blend. Coating technology offers a solution to increase the wear resistance and consequently the lifetime of those components. The aim of this study is the evaluation of the micro-abrasive wear resistance of a range of commercially available hard and/or low friction coatings against rutile particles. Therefore, ball cratering tests EXPERIMENTAL SET-UP The tests were performed on a TE66 micro-scale abrasion tester manufactured by Plint. As abrasive suspensions, a typical rutile powder with small particle size (Ø 0.1-0.4 µm) and spherical grains in distilled water was used. Ball bearing steel was used as counterbody. The selected coatings ranged from hard ceramic coatings to softer low friction coatings. Four PVD coatings were used (TiN, CrN, TiCN and low temperature CrN), one CVD (TiN) and three PACVD (DLC and diamond-like nanocomposites Dylyn ® a-C:H/a-Si:O) TEST RESULTS AND EVALUATION The micro abrasion test resulted in a clear ranking of the selected coatings in function of the wear coefficient. In general, the hard ceramic coatings have the lowest wear coefficient. DLC and CrN performed very well. The softer coating types which are designed for reduction of the surface energy, such as NiP+PTFE, show an increase in wear of three orders of magnitude. However, there is no evidence for a close correlation between the wear rate and the coating hardness measured by depth sensing indentation. Only when the three very similar PACVD coatings are considered separately, the wear coefficient is significantly increasing with decreasing coating hardness. The results are obtained by using the extended Archard equation: with K c and K s are the wear coefficients of the coating and substrate respectively, V c and V s the measured wear volumes and SN the sliding distance multiplied by the applied load. Different ways of implementing equatio
Information sharing and credit : firm-level evidence from transition countries
We investigate whether information sharing among banks has affected credit market performance in the transition countries of Eastern Europe and the former Soviet Union, using a large sample of firm-level data. Our estimates show that information sharing is associated with improved availability and lower cost of credit to firms. This correlation is stronger for opaque firms than transparent ones and stronger in countries with weak legal environments than in those with strong legal environments. In cross-sectional estimates, we control for variation in country-level aggregate variables that may affect credit, by examining the differential impact of information sharing across firm types. In panel estimates, we also control for the presence of unobserved heterogeneity at the firm level, as well as for changes in macroeconomic variables and the legal environment
Oplossingen voor bodemmoeheid in de fruitteelt
De herinplant in de fruitteelt is alleen mogelijk als de bodemmoeheid wordt aangepakt. Alternatieve methoden van grondontsmetting waren tot nu toe in de meeste gevallen minder effectief of in vergelijking met chemische grondontsmetting veel duurder. In de biologische fruitteelt is chemische ontsmetting geen optie. Uit recent onderzoek blijken een aantal biologische behandelingen geschikt om bodemmoeheid te bestrijden: zwarte braak, Tagetes (Afrikaantjes) en biologische grondontsmetting (BGO). Biofumigatie en compost bleken minder effectief of geschikt
Consumer credit information systems: A critical review of the literature. Too little attention paid by lawyers?
This paper reviews the existing literature on consumer credit reporting, the most extensively used instrument to overcome information asymmetry and adverse selection problems in credit markets. Despite the copious literature in economics and some research in regulatory policy, the legal community has paid almost no attention to the legal framework of consumer credit information systems, especially within the context of the European Union. Studies on the topic, however, seem particularly relevant in view of the establishment of a single market for consumer credit. This article ultimately calls for further legal research to address consumer protection concerns and inform future legislation
Clan CD of cysteine peptidases as an example of evolutionary divergences in related protein families across plant clades
Comparative genomic analyses are powerful tools that can be used to analyze the presence, conservation, and evolution of protein families and to elucidate issues concerning their function. To deal with these questions, we have chosen the clan CD of cysteine peptidases, which is formed by different protein families that play key roles in plants. An evolutionary comparative analysis of clan CD cysteine peptidases in representative species of different taxonomic groups that appeared during the evolution of the Viridiplantae was performed. The results obtained indicates: i) C13 GPI:protein transamidases, C14 metacaspases I, and C50 separases are present in all taxonomic groups; ii) C13 legumains and C14 metacaspases II are absent in some basal algae groups; iii) C11 clostripains have only been found in the two Chlorophyceae species; iv) C25 gingipains and C80 RTX toxins have not been found in plants. Moreover, gene duplication events could have been associated in some families to the increasing complexities acquired in land plants. These findings have demonstrated that comparative genomics is useful to provide valuable insights on the differential evolution of the related peptidase families belonging to clan CD in plant clades. The low number of protein members suggests a restricted physiological role for these peptidase families, mainly in algae species
Multivariate analysis of 3D ToF-SIMS images: method validation and application to cultured neuronal networks
Advanced data analysis tools are crucial for the application of ToF-SIMS analysis to biological samples. Here, we demonstrate that by using a training set approach principal components analysis (PCA) can be performed on large 3D ToF-SIMS images of neuronal cell cultures. The method readily provides access to sample component information and significantly improves the images’ signal-to-noise ratio (SNR)
Evaluating the impact of accounting for coral cover in large‐scale marine conservation prioritizations
Aim
Mega‐diverse coral reef ecosystems are declining globally, necessitating conservation prioritizations to protect biodiversity and ecosystem services of sites with high functional integrity to promote persistence. In practice however, the design of marine‐protected area (MPA) systems often relies on broad classifications of habitat class and size, making the tacit assumption that all reefs are of comparable condition. We explored the impact of this assumption through a novel, pragmatic approach for incorporating variability in coral cover in a large‐scale regional spatial prioritization plan.
Location
The Coral Triangle.
Methods
We developed a spatially explicit predictive model of hard coral cover based on freely available macro‐ecological data to generate a complete regional map of coral cover as a proxy for reef condition. We then incorporate this information in spatial conservation prioritization software Marxan to design an MPA system that meets specific conservation objectives.
Results
We discover prioritizations using area‐based representation of reef habitat alone may overestimate the conservation benefit, defined as the amount of hard coral cover protected, by up to 64%. We find substantial differences in conservation priorities and an overall increase in habitat quality metrics when accounting for predicted coral cover.
Main conclusions
This study shows that including habitat condition in a large‐scale marine spatial prioritization is feasible within time and resource constraints, and calls for increased implementation, and evaluation, of such ecologically relevant planning approaches to enhance potential conservation effectiveness
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