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911.
Little is known about the effects of different prey species on lizard growth. We conducted a 6‐week study to determine the relative effects of prey species on growth parameters of hatchling western fence lizards, Sceloporus occidentalis. Lizards were fed house cricket nymphs, Acheta domesticus, or mealworm larvae, Tenebrio molitor. The effects of prey species on growth were determined by measuring prey consumption, gross conversion efficiency of food [gain in mass (g)/food consumed (g)], gain in mass, and gain in snout–vent length. Lizards grew well on both the prey species. However, lizards that fed on crickets consumed a significantly higher percentage of their body mass per day than those fed mealworms. Nevertheless, lizards that consumed mealworms ingested significantly more metabolizable energy, had significantly higher food conversion efficiencies, significantly higher daily gains in mass, and significantly greater total growth in mass than lizards that fed on crickets. Zoo Biol 27:181–187, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
912.
ZAYNAB ESSACK JENNIFER KOEN NICOLA BARSDORF CATHERINE SLACK MICHAEL QUAYLE CECILIA MILFORD GRAHAM LINDEGGER CHITRA RANCHOD RICHARD MUKUKA 《Developing world bioethics》2010,10(1):11-21
There is little published literature on the ethical concerns of stakeholders in HIV vaccine trials. This study explored the ethical challenges identified by various stakeholders, through an open-ended, in-depth approach. While the few previous studies have been largely quantitative, respondents in this study had the opportunity to spontaneously identify the issues that they perceived to be of priority concern in the South African context. Stakeholders spontaneously identified the following as ethical priorities: informed consent, social harms, collaborative relationships between research stakeholders, the participation of children and adolescents, access to treatment for participants who become infected with HIV, physical harms, fair participant and community selection, confidentiality, benefits, and payment.
While there is some speculation that research in developing countries poses special ethical challenges, overall no issues were identified that have not been anticipated in international guidance, literature and popular frameworks. However, the South African context affords a distinctive gloss to these expected issues; for example, respondents were concerned that the predominant selection of black participants may perpetuate racist practices of apartheid. Stakeholders should be aware of contextual factors impacting on the implementation of ethical principles. We make a series of recommendations for South African trials, including amendments to the ethical-legal framework and research policies, and, for further research. 相似文献
While there is some speculation that research in developing countries poses special ethical challenges, overall no issues were identified that have not been anticipated in international guidance, literature and popular frameworks. However, the South African context affords a distinctive gloss to these expected issues; for example, respondents were concerned that the predominant selection of black participants may perpetuate racist practices of apartheid. Stakeholders should be aware of contextual factors impacting on the implementation of ethical principles. We make a series of recommendations for South African trials, including amendments to the ethical-legal framework and research policies, and, for further research. 相似文献
913.
《Expert review of proteomics》2013,10(5):565-575
While proteomic methods have illuminated many areas of biological protein space, many fundamental questions remain with regard to systems-level relationships between mRNAs, proteins and cell behaviors. While mass spectrometric methods offer a panoramic picture of the relative expression and modification of large numbers of proteins, they are neither optimal for the analysis of predefined targets across large numbers of samples nor for assessing differences in proteins between individual cells or cell compartments. Conversely, traditional antibody-based methods are effective at sensitively analyzing small numbers of proteins across small numbers of conditions, and can be used to analyze relative differences in protein abundance and modification between cells and cell compartments. However, traditional antibody-based approaches are not optimal for analyzing large numbers of protein abundances and modifications across many samples. In this article, we will review recent advances in methodologies and philosophies behind several microarray-based, intermediate-level, ‘protein-omic’ methods, including a focus on reverse-phase lysate arrays and micro-western arrays, which have been helpful for bridging gaps between large- and small-scale protein analysis approaches and have provided insight into the roles that protein systems play in several biological processes. 相似文献
914.
《Palaeoworld》2023,32(2):202-218
Strata equivalent to the majority of the Ordovician shallow-water sediments in South China occur in the western Yangtze region (present-day southwestern Sichuan and northeastern Yunnan, Southwest China), but remain to be properly documented largely due to their inaccessibility. Our research in the past decade has led to the recognition of spatial and temporal patterns, and hence a substantial stratigraphic revision of these rocks, with part of the results having been published in a series of papers. Here, we outline a unified and refined Ordovician stratigraphy of the region built chiefly on a summary of these new data, presenting a robust timeframe for exploring the environmental and biotic events during the Ordovician on a basin-wide scale in South China. 相似文献
915.
Todd A. Ugine Stephen P. Wraight John P. Sanderson 《Biocontrol Science and Technology》2007,17(2):193-219
The effects of various spray application parameters on the efficacy of a clay-based wettable powder formulation of Beauveria bassiana strain GHA conidia against western flower thrips, Frankliniella occidentalis, were evaluated in a series of greenhouse tests. With the aim of optimizing spray application methods to maximize biopesticide efficacy, a series of independent experiments was conducted that varied four spray parameters: application interval, rate, volume, and spray-program timing. Impatiens crops infested with western flower thrips were treated with (1) multiple sprays at the rate of 5×1013 conidia in 935 L aqueous carrier ha?1 applied at 3-, 5-, and 7-day intervals, (2) weekly sprays at rates of 5×1013, 1×1014, and 2.0×1014 conidia in 935 L carrier ha?1, (3) weekly sprays at a rate of 2.0×1014 conidia in volumes of 935, 1870, and 3740 L water ha?1, and (4) multiple sprays at the rate of 2.0×1014 conidia in 3740 L carrier ha?1 applied at 5-day intervals in spray programs initiated before versus after the onset of flowering. Pollen-bearing impatiens flowers were sampled twice weekly to estimate thrips population density, and adult female and second-instar thrips were collected 24 h post application for determination of acquired dose (conidia/insect). Numbers of conidia inoculated onto thrips increased with increasing spray frequency and volume. Dose was unexpectedly not directly correlated with application rate when volume was held constant, suggesting that thrips avoided concentrated spray residues. Statistically significant thrips population reductions relative to controls were achieved only when three to four sprays were applied at the highest label rate in the highest volume at < 7-day intervals. Applications against thrips infesting young, preflowering impatiens crops were not consistently more effective than applications in older crops. The most effective treatment programs reduced pest populations by 30–40% compared to untreated controls; this slowed, but did not stop, the growth of pest populations. Results indicate that use of fungi for thrips management will require integration with other control agents. 相似文献
916.
917.
918.
Increasing the Understanding of Plant Invasions in Southern South America: First Symposium on Alien Plant Invasions in Chile 总被引:2,自引:2,他引:0
A. Pauchard L. Cavieres R. Bustamante P. Becerra E. Rapoport 《Biological invasions》2004,6(2):255-257
The first symposium on Alien Plant Invasions in Chile was held in southern Chile in November of 2002. Chile represents an interesting setting to study biological invasions because of its long history of introductions, and its high rate of endemisms that makes it more prone to invasions. However, little is known about plant invasions in Chile and the country lacks a clear policy on alien species. The speakers at the symposium discussed their research on several aspects of alien plant invasions in southern Chile and Argentina. They also elaborated a list of future challenges of plant invasion ecology for the area. The package of recommendations may be useful for other developing countries with similar state of knowledge of their flora and similar environmental and economic issues. We expect that this type of meeting will help to stimulate the scientific debate about invasion ecology and the development of coordinated research to answer local questions, while contributing to find generalities in plant invasion patterns and processes. 相似文献
919.
Seasonal influenzas are annually responsible for hundreds of thousands of deaths worldwide, often because of insufficient care, which may depend on orientations of economic policy. Yet, the empirical evidence on the relations existing between policies based on different degrees of economic liberalism and flu mortality is still scarce. This paper contributes to filling the gap by proposing an empirical investigation into the effects of various dimensions of liberalism, proxied by the different components of the Fraser Index of Economic Freedom, on deaths from seasonal influenzas in a sample of 38 OECD countries observed from 1970 to 2018. A dynamic panel System-GMM estimator is used to alleviate endogeneity concerns, while alternative models, specifications and subsamples check the robustness of findings. Findings show that: a) not every component of economic freedom has an effect on flu mortality; b) more economic freedom not always means less or more deaths from flu. In particular, stronger protection of property rights and smaller government consumption are associated with higher flu mortality, which is instead lower when people and capital are freer to move. Such results give rise to policy considerations and contribute to inform policymakers about actions that can limit the mortality of a globally widespread disease like flu. 相似文献
920.
B. A. Marshall 《New Zealand journal of zoology.》2013,40(4):487-492
Abstract The taxonomic status and synonymy of Williamia Monterosato, 1884 are discussed. Williamia is retained in preference to Allerya Mörch, 1877 and Brondelia Bourguignat, 1862, both of which have priority. Roya Iredale, 1912 is transferred from Trochidae to Siphonariidae as a synonym of Williamia. Roya kermadecensis Iredale, 1912 is synonymised with Capulus nutatus Hedley, 1908, which in turn is placed as a geographic subspecies of W. radiata Pease, 1861. Allerya japonica Habe, 1962 is considered a probable synonym of W. radiata. W. maxwelli n.sp. is described from the Upper Oligocene to Lower Miocene of New Zealand. Roya spongotheras Bertsch, 1980 is transferred to an undescribed genus of the Tylodinidae. 相似文献