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991.
992.
Animal Preferences and Acceptability of Wildlife Management Actions around Serengeti National Park, Tanzania 总被引:1,自引:0,他引:1
Bjørn P. Kaltenborn Tore Bjerke Julius W. Nyahongo Daniel R. Williams 《Biodiversity and Conservation》2006,15(14):4633-4649
Wildlife management policies are often based on expert perceptions of the ecological importance of certain species and poorly
informed perceptions of how public attitudes toward management are formed. Little is known about why preferences vary greatly
and how this affects support for management actions. This paper explores preferences for a range of wildlife species among
a sample of the rural population adjacent to Serengeti National Park in Tanzania. We also examine the degree of acceptance
for alternative management interventions when potentially dangerous animals pose different levels of problems to human beings,
and the extent to which these attitudes are related to species preferences. Gender has a significant effect on species preferences.
Men like most species better than women. Age has no significant effect, but level of education affects preference level for
some species. Species preferences have a positive effect on support for management intervention when dangerous animals cause
small or moderate problems to humans, i.e. there is a higher degree of acceptance of problems caused by animals that are well
liked. In situations where human life is threatened, species preferences have no effect on preferred management actions. Appreciation
of animals is a combination of functional, consumptive and cultural dimensions, and there is no simple link between species
preferences and attitudes toward management actions. The local context and concrete experience with wildlife encounters is
more important for shaping normative beliefs like attitudes towards management actions than global wildlife attitudes. 相似文献
993.
Stomatin-like protein 2 (SLP-2) (syn.: EPB72-like 2 [NP_038470], HSPC108 [AAF29073]), a protein of unknown function, has been described in several tissues and cells but its primary structure is still not completely elucidated. Moreover, sequence conflicts appear in several databases. It was the aim of the study to further describe SLP-2 primary sequence and to solve existing sequence conflicts. For this purpose a protein extract was run on two-dimensional gel electrophoresis and SLP-2 was identified by MALDI-TOF/TOF. SLP-2 was digested with trypsin, chymotrypsin, Lys-C, and de novo sequencing studies as well as Nano-HPLC-ESI-MS/MS analysis were carried out. By the use of several proteases sequence coverage of 90% was obtained but the N-terminal 34 amino acids harbouring database conflict 1 were not covered. The presence of Leucine 129 (sequence conflict 2) and Alanine 202 (sequence conflict 3) was verified by three independent approaches. High sequence coverage resulting from multiple proteolytic cleavage, MALDI-TOF/TOF, Nano-HPLC-ESI-MS/MS and de novo sequencing completed unambiguous analysis of SLP-2 primary structure of approximately = 90% of sequence coverage. In addition, methodology used was able to solve so far pending sequence conflicts in databases and literature. SLP-2 is a high abundance protein in several tissues and cells and may play an important biological role and therefore characterization of its primary structure is of importance. 相似文献
994.
Daniel Olivieri Martina M Sykora Ravi Sachidanandam Karl Mechtler Julius Brennecke 《The EMBO journal》2010,29(19):3301-3317
In Drosophila, PIWI proteins and bound PIWI‐interacting RNAs (piRNAs) form the core of a small RNA‐mediated defense system against selfish genetic elements. Within germline cells, piRNAs are processed from piRNA clusters and transposons to be loaded into Piwi/Aubergine/AGO3 and a subset of piRNAs undergoes target‐dependent amplification. In contrast, gonadal somatic support cells express only Piwi, lack signs of piRNA amplification and exhibit primary piRNA biogenesis from piRNA clusters. Neither piRNA processing/loading nor Piwi‐mediated target silencing is understood at the genetic, cellular or molecular level. We developed an in vivo RNAi assay for the somatic piRNA pathway and identified the RNA helicase Armitage, the Tudor domain containing RNA helicase Yb and the putative nuclease Zucchini as essential factors for primary piRNA biogenesis. Lack of any of these proteins leads to transposon de‐silencing, to a collapse in piRNA levels and to a failure in Piwi‐nuclear accumulation. We show that Armitage and Yb interact physically and co‐localize in cytoplasmic Yb bodies, which flank P bodies. Loss of Zucchini leads to an accumulation of Piwi and Armitage in Yb bodies, indicating that Yb bodies are sites of primary piRNA biogenesis. 相似文献
995.
Background
Haplotype reconstruction is important in linkage mapping and association mapping of quantitative trait loci (QTL). One widely used statistical approach for haplotype reconstruction is simulated annealing (SA), implemented in SimWalk2. However, the algorithm needs a very large number of sequential iterations, and it does not clearly show if convergence of the likelihood is obtained. 相似文献996.
Sagun Julius Ver Badger Murray R. Chow Wah Soon Ghannoum Oula 《Photosynthesis research》2021,149(1-2):171-185
Photosynthesis Research - Alternative electron fluxes such as the cyclic electron flux (CEF) around photosystem I (PSI) and Mehler reaction (Me) are essential for efficient photosynthesis because... 相似文献
997.
998.
999.
Plasmodium sporozoites, the infective stage of the malaria parasite transmitted by mosquitoes, migrate through several hepatocytes before infecting a final one. Migration through hepatocytes occurs by breaching their plasma membranes, and final infection takes place with the formation of a vacuole around the sporozoite. Once in the liver, sporozoites have already reached their target cells, making migration through hepatocytes prior to infection seem unnecessary. Here we show that this migration is required for infection of hepatocytes. Migration through host cells, but not passive contact with hepatocytes, induces the exocytosis of sporozoite apical organelles, a prerequisite for infection with formation of a vacuole. Sporozoite activation induced by migration through host cells is an essential step of Plasmodium life cycle. 相似文献
1000.
Rap2-JNK removes synaptic AMPA receptors during depotentiation 总被引:5,自引:0,他引:5
Zhu Y Pak D Qin Y McCormack SG Kim MJ Baumgart JP Velamoor V Auberson YP Osten P van Aelst L Sheng M Zhu JJ 《Neuron》2005,46(6):905-916
The related small GTPases Ras and Rap1 are important for signaling synaptic AMPA receptor (-R) trafficking during long-term potentiation (LTP) and long-term depression (LTD), respectively. Rap2, which shares 60% identity to Rap1, is present at excitatory synapses, but its functional role is unknown. Here, we report that Rap2 activity, stimulated by NR2A-containing NMDA-R activation, depresses AMPA-R-mediated synaptic transmission via activation of JNK rather than Erk1/2 or p38 MAPK. Moreover, Rap2 controls synaptic removal of AMPA-Rs with long cytoplasmic termini during depotentiation. Thus, Rap2-JNK pathway, which opposes the action of the NR2A-containing NMDA-R-stimulated Ras-ERK1/2 signaling and complements the NR2B-containing NMDA-R-stimulated Rap1-p38 MAPK signaling, channels the specific signaling for depotentiating central synapses. 相似文献