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61.
A simple regional habitat model founded on the relation between vertical habitat complexity and species richness has been
used to describe wildlife habitat in response to macroscale patterns in land use and land cover. While the model has a basis
in ecological theory, it has not been subjected to rigorous testing. We evaluated the model's fundamental assumption on landscapes
in the eastern forested region of the United States and found the model to be supported when we used a measure of avian community
integrity during the breeding season. The model was improved by incorporating measures of horizontal heterogeneity, indicating
that the vertical and horizontal structure of habitats should be considered in analyzing the response of wildlife to land
resource policies that can affect broad land use patterns.
In cooperation with Colorado State University. 相似文献
62.
M Brady G Refshauge S Robertson T Atkinson B Allworth M Hernandez-Jover 《Australian veterinary journal》2020,98(12):602-609
The Australian goat meat industry has grown significantly in the last decade, with the value of exports nearly tripling. However, because carcase weight has remained constant over this time, the drivers of industry growth are price and supply. Animal health and reproduction are key factors contributing to supply and productivity, yet limitations to production management are poorly understood, hampering advice for effective intervention. This exploratory study aims to provide insights into the animal health and reproductive management practices and perceptions among meat goat producers in Australia. To achieve this aim, 20 producers, located in New South Wales, Queensland, Western Australia and Victoria, operating under different production systems were interviewed. The results of this study suggest that animal health management could be improved and that producers perceive a lack of relevant and species-specific information available to help them make informed decisions. Reproductive management and records varied greatly across producers interviewed. Kid loss was identified as an issue, with a 28% estimated average (6%–47% range) of losses from kidding until weaning. Producers identified predation, doe nutrition and mismothering as the biggest contributors to kid loss, with the majority of losses occurring within a week of birth. All producers believed management could minimise kid loss. This study highlights the importance of improving reproductive rates among goat enterprises and provides new information on the current practices within the Australian meat goat industry. This may assist the development of appropriate strategies for improving health and reproductive management and delivery of advice to producers. 相似文献
63.
Wang Q Zhao J Brady AE Feng J Allen PB Lefkowitz RJ Greengard P Limbird LE 《Science (New York, N.Y.)》2004,304(5679):1940-1944
Arrestin regulates almost all G protein-coupled receptor (GPCR)-mediated signaling and trafficking. We report that the multidomain protein, spinophilin, antagonizes these multiple arrestin functions. Through blocking G protein receptor kinase 2 (GRK2) association with receptor-Gbetagamma complexes, spinophilin reduces arrestin-stabilized receptor phosphorylation, receptor endocytosis, and the acceleration of mitogen-activated protein kinase (MAPK) activity following endocytosis. Spinophilin knockout mice were more sensitive than wild-type mice to sedation elicited by stimulation of alpha2 adrenergic receptors, whereas arrestin 3 knockout mice were more resistant, indicating that the signal-promoting, rather than the signal-terminating, roles of arrestin are more important for certain response pathways. The reciprocal interactions of GPCRs with spinophilin and arrestin represent a regulatory mechanism for fine-tuning complex receptor-orchestrated cell signaling and responses. 相似文献
64.
Stereoisomers of N-allylnormetazocine: phencyclidine-like behavioral effects in squirrel monkeys and rats 总被引:9,自引:0,他引:9
(+/-)-N-Allylnormetazocine is a benzomorphan opioid with psychotomimetic effects. The pure stereoisomers of this compound, as well as the racemic mixture, were compared to phencyclidine for their behavioral effects on squirrel monkeys and rats trained to discriminate phencyclidine from saline. Dose-response determinations were made for responses to phencyclidine, to a racemic mixture of N-allylnormetazocine, and to the pure levo and dextro isomers of N-allylnormetazocine. In both rats and monkeys, the dextro isomer and the racemic mixture produced dose-dependent responses appropriate for phencyclidine; the levo isomer did not produce the responses appropriate for phencyclidine at any of the doses tested. In both species, the levo isomer was more potent than the dextro isomer in decreasing the rate of responding. Thus racemic N-allylnormetazocine is a mixture of compounds that produce different behavioral effects. 相似文献
65.
Wild P Farhan H McEwan DG Wagner S Rogov VV Brady NR Richter B Korac J Waidmann O Choudhary C Dötsch V Bumann D Dikic I 《Science (New York, N.Y.)》2011,333(6039):228-233
Selective autophagy can be mediated via receptor molecules that link specific cargoes to the autophagosomal membranes decorated by ubiquitin-like microtubule-associated protein light chain 3 (LC3) modifiers. Although several autophagy receptors have been identified, little is known about mechanisms controlling their functions in vivo. In this work, we found that phosphorylation of an autophagy receptor, optineurin, promoted selective autophagy of ubiquitin-coated cytosolic Salmonella enterica. The protein kinase TANK binding kinase 1 (TBK1) phosphorylated optineurin on serine-177, enhancing LC3 binding affinity and autophagic clearance of cytosolic Salmonella. Conversely, ubiquitin- or LC3-binding optineurin mutants and silencing of optineurin or TBK1 impaired Salmonella autophagy, resulting in increased intracellular bacterial proliferation. We propose that phosphorylation of autophagy receptors might be a general mechanism for regulation of cargo-selective autophagy. 相似文献
66.
67.
68.
Joshua H. Goldstein Wayne E. Thogmartin Kenneth J. Bagstad James A. Dubovsky Brady J. Mattsson Darius J. Semmens 《Human Dimensions of Wildlife》2014,19(4):347-354
Migratory species provide economically beneficial ecosystem services to people throughout their range, yet often, information is lacking about the magnitude and spatial distribution of these benefits at regional scales. We conducted a case study for Northern Pintails (hereafter pintail) in which we quantified regional and sub-regional economic values of subsistence harvest to indigenous communities in Arctic and sub-Arctic North America. As a first step, we used the replacement cost method to quantify the cost of replacing pintail subsistence harvest with the most similar commercially available protein (chicken). For an estimated annual subsistence harvest of ?15,000 pintail, our mean estimate of the total replacement cost was ?$63,000 yr?1 ($2010 USD), with sub-regional values ranging from $263 yr?1 to $21,930 yr?1. Our results provide an order-of-magnitude, conservative estimate of one component of the regional ecosystem-service values of pintails, providing perspective on how spatially explicit values can inform migratory species conservation. 相似文献
69.
Peptide toxins typically bind to their target ion channels or receptors with high potency and selectivity, making them attractive leads for therapeutic development. In some cases the native peptide as it is found in the venom from which it originates can be used directly, but in many instances it is desirable to truncate and/or stabilize the peptide to improve its therapeutic properties. A complementary strategy is to display the key residues that make up the pharmacophore of the peptide toxin on a non-peptidic scaffold, thereby creating a peptidomimetic. This review exemplifies these approaches with peptide toxins from marine organisms, with a particular focus on conotoxins. 相似文献
70.
Masoud Taghizadeh Aoife A. Gowen Colm P. O’Donnell 《Computers and Electronics in Agriculture》2011,77(1):74-80
The potential of hyperspectral imaging (HSI) in the visible-near infrared (445-945 nm) wavelength range to discriminate between casing soil, enzymatic browning and undamaged tissue on mushroom (Agaricus bisporus) surfaces was investigated. A calibration set of 108 damage free mushrooms, grown under controlled conditions in a research station, were first tested as undamaged class (U) and then were divided into 2 groups of 54 samples. The first group was smeared with casing soil and designated as casing soil class (C) and the second group was subjected to vibrational damage resulting in enzymatic browning and designated as damaged class (D). Partial least squares discriminant analysis (PLS-DA) models were developed to classify mushroom tissue as one of the three classes investigated (U, C and D) using pixel spectra from each class. Prediction maps were obtained by applying the developed models to the hyperspectral images of candidate mushrooms. Percentages of pixels classified into each class were also calculated for the mushrooms studied in the calibration set. Results obtained showed that the developed models performed satisfactorily to discriminate between the 3 classes studied. Comparison of red-green-blue (RGB) and hyperspectral image analysis showed that HSI was better able to identify the regions containing casing soil. Model validation was performed using 3 different test sets of mushrooms obtained from a commercial producer. It was found that the developed PLS-DA models were satisfactorily capable of identifying undamaged regions, casing soil and enzymatic damaged areas on mushrooms from the validation sets. 相似文献