66 resultados para Hunting dogs
Resumo:
The absolute volume of Weibel-Palade (WP) bodies, the storage organelles of von Willebrand factor (vWF), was estimated by a stereological method in a known volume of central retina from normal and 5-year diabetic dogs. The results showed that the volume of WP bodies present in the endothelium of the retinal vasculature varies with blood vessel type and in diabetes. In both diabetic and normal dogs the endothelium of the retinal veins contained a higher volume of WP bodies than that of the retinal arteries. In dogs which had been diabetic for a duration of 5 years the volume of WP bodies present in the endothelium of retinal veins was significantly greater than in the endothelium of veins from the control animals. However, there was no significant difference in the volume of WP bodies present in the endothelium of retinal arteries or capillaries between the two groups of animals.
Resumo:
This study was undertaken to further characterise the fine structural changes occurring in the retinal circulation in early diabetes. The eyes of eight alloxan/streptozotocin and three spontaneously diabetic dogs were examined by trypsin digest and electron microscopy after durations of diabetes of between 1 and 7 years. Basement membrane (BM) thickening in the retinal capillaries was the only obvious fine structural change identified during the first 3 years of diabetes and was established within 1 year of induction. Widespread pericyte loss was noted after 4 years of diabetes and was paralleled by loss of smooth muscle (SM) cells, in the retinal arterioles. SM cell loss was most obvious in the smaller arterioles of the central retina. No microaneurysms were noted in the experimental diabetic dogs with up to 5 years' duration of diabetes but were widespread in a spontaneously diabetic animal at 7 years. This study has shown that SM cell loss, a hitherto unrecognised feature of diabetic microangiopathy, accompanies pericyte loss in the retinal circulation of diabetic dogs.
Resumo:
The diabetic dog represents an excellent model for use in many aspects of diabetic research. The present paper describes, in detail, a reproducible experimental protocol for the successful induction of chemical diabetes in beagles using a combination of the 2 pancreatic beta-cell cytoxic agents alloxan and streptozotocin.
Resumo:
Experiments were undertaken to characterize a noninvasive chronic, model of nasal congestion in which nasal patency is measured using acoustic rhinometry. Compound 48/80 was administered intranasally to elicit nasal congestion in five beagle dogs either by syringe (0.5 ml) in thiopental sodium-anesthetized animals or as a mist (0.25 ml) in the same animals in the conscious state. Effects of mast cell degranulation on nasal cavity volume as well as on minimal cross-sectional area (A(min)) and intranasal distance to A(min) (D(min)) were studied. Compound 48/80 caused a dose-related decrease in nasal cavity volume and A(min) together with a variable increase in D(min). Maximal responses were seen at 90-120 min. Compound 48/80 was less effective in producing nasal congestion in conscious animals, which also had significantly larger basal nasal cavity volumes. These results demonstrate the utility of using acoustic rhinometry to measure parameters of nasal patency in dogs and suggest that this model may prove useful in studies of the actions of decongestant drugs.
Resumo:
According to the axiomatic literature on consensus methods, the best collective choice by one method of preference aggregation can easily be the worst by another. Are award committees, electorates, managers, online retailers, and web-based recommender systems stuck with an impossibility of rational preference aggregation? We investigate this social choice conundrum for seven social choice methods: Condorcet, Borda, Plurality, Antiplurality, the Single Transferable Vote, Coombs, and Plurality Runoff. We rely on Monte Carlo simulations for theoretical results and on twelve ballot datasets from American Psychological Association (APA) presidential elections for empirical results. Each of these elections provides partial rankings of five candidates from about 13,000 to about 20,000 voters. APA preferences are neither domain-restricted nor generated by an Impartial Culture. We find virtually no trace of a Condorcet paradox. In direct contrast with the classical social choice conundrum, competing consensus methods agree remarkably well, especially on the overall best and worst options. The agreement is also robust under perturbations of the preference prole via resampling, even in relatively small pseudosamples. We also explore prescriptive implications of our findings.
Resumo:
In this chapter Morrow talks of her return to Northern Ireland to 2003 and how her involvement in establishing a new school of architecture and a recent suite of interdisciplinary masters has led her to consider the relationship between the post-conflict context, architectural practice and its education. She examines the consequences of not facing the effects of conflict; the impact on societal and architectural creativity; and the potential for live project pedagogy to evolve effective models of socio-spatial rehearsals. She concludes with some strategies for schools of architecture that wish to feed and be fed by their context. This is a personalized commentary that teeters somewhere between deep-seated frustration with a blind-folded profession and sustained belief in architectural education’s potential to offer more than built solutions.
Resumo:
Renewed archaeological investigation of the West Mouth of Niah Cave, Borneo has demonstrated that even within lowland equatorial environments depositional conditions do exist where organic remains of late glacial and early post-glacial age can be preserved. Excavations by the Niah Cave Research Project (NCP) (2000-2003) towards the rear of the archaeological reserve produced several bone points and worked stingray spines, which exhibit evidence of hafting mastic and fibrous binding still adhering to their shafts. The position of both gives strong indication of how these cartilaginous points were hafted and gives insight into their potential function. These artefacts were recovered from secure and (14)C dated stratigraphic horizons. The results of this study have implications for our understanding the function of the Terminal Pleistocene and Early Holocene bone tools recovered from other regions of Island Southeast Asia. They demonstrate that by the end the Pleistocene rainforest foragers in Borneo were producing composite technologies that probably included fishing leisters and potentially the bow and arrow. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
The Terminal Pleistocene zooarchaeological evidence from Lobang Hangus, an east-facing entrance to the Niah Cave complex, provides unique insights into the hunting habits of the human inhabitants of this cave. The composition and structure of the vertebrate accumulation indicates that a variety of locally available terrestrial, arboreal and aquatic taxa were being exploited, The age structure of the principal predated species, the presence of bone points and evidence from modern rainforest hunting combine to suggest that some form of projectile weaponry as well as trapping technologies were probably being employed by the hunters at Niah before the end of the Pleistocene. Copyright (C) 2009 John Wiley & Sons, Ltd.
Resumo:
In Italy, standards for the management of free-roaming dogs (FRDs) are defined by regional norms, generating a high variability of approaches around the country. Despite efforts carried out by the competent authorities, FRDs are still a reality impacting upon animal health and welfare and public costs. A similar scenario can be found in many other Mediterranean and Balkan counties. Here we present 14 years of data (2000–2013) retrieved from the admission dog registry of a public shelter (PS) responsible for the collection of stray dogs from one Italian province. The aim of this retrospective study was to describe the local FRD population, identifying its source and to evaluate the effectiveness of the actions implemented by the local authorities. In the investigated period, 7,475 dogs were admitted to the PS. Despite the intense sterilisation plan (mean 381.7 sterilisations per year), the overall number of dogs entering PS did not decrease consistently across the years. Results highlighted a lack of responsibility of owners by failing to sterilise and identify their dogs and allowing intact animals to roam free, therefore producing uncontrolled and unwanted litters. The current dog population management strategy, based on both sheltering and capture-neuter-release programmes, is insufficient to tackle the straying phenomenon. Educational and sterilisation programmes should be an integral part of a successfully implemented FRD control plan. Our results provide further insight on free-roaming dog population dynamics and control systems, and may have important implications for many other local contexts across Europe trying to overcome the straying phenomenon.