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971.
The Australian sleepy lizard, Tiliqua rugosa, maintains monogamous associations for an average of 6 weeks before mating each spring. One hypothesis to explain this prolonged partnership is that males are guarding their female partners from rival males. This hypothesis has three predictions, that males are more aggressive than females to conspecific males, that male aggression will increase as the time of mating gets closer, and that males will be more aggressive towards conspecific males when they are with their partner than when they are alone. We tested those predictions with indirect evidence of aggression, using counts of scale damage on randomly encountered lizards, and with direct observations of their responses to approaches by conspecific and heterospecific models. As predicted by the mate guarding hypothesis, males showed more evidence of aggression towards conspecifics than did females. However, in contrast to the hypothesis, males did not become more aggressive as the time of mating came closer, and males in pairs were less aggressive than males on their own. Mate guarding cannot be the only process that has led to the prolonged monogamous associations in this species. Parental care is also unknown in these lizards, and we suggest that monogamy may be maintained through some form of female coercion, allowing females to gain additional fitness from the enhanced vigilance that results from male proximity. 相似文献
972.
Vitaly L. Budarin James H. Clark Brigid A. Lanigan Peter Shuttleworth Simon W. Breeden Ashley J. Wilson Duncan J. Macquarrie Kris Milkowski Jenny Jones Toby Bridgeman Andy Ross 《Bioresource technology》2009,100(23):6064-6068
The low temperature microwave activation of biomass has been investigated as a novel, energy efficient route to bio-oils. The properties of the bio-oil produced were considered in terms of fuel suitability. Water content, elemental composition and calorific value have all been found to be comparable to and in many cases better than conventional pyrolysis oils. Compositional analysis shows further differences with conventional pyrolysis oils including simpler chemical mixtures, which have potential as fuel and chemical intermediates. The use of simple additives, e.g. HCl, H2SO4 and NH3, affects the process product distribution, along with changes in the chemical composition of the oils. Clearly the use of our low temperature technology gives significant advantages in terms of preparing a product that is much closer to that which is required for transport fuel applications. 相似文献
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The concept of benefit sharing pertains to the act of giving something in return to the participants, communities, and the country that have participated in global health research or bioprospecting activities. One of the key concerns of benefit sharing is the ethical justifications or reasons to support the practice of the concept in global health research and bioprospecting. This article evaluates one of such ethical justifications and its meaning to benefit sharing, namely justice. We conducted a systematic review to map the various principles of justice that are linked to benefit sharing and analysed their meaning to the concept of benefit sharing. Five principles of justice (commutative, distributive, global, procedural, and compensatory) have been shown to be relevant in the nuances of benefit sharing in both global health research and bioprospecting. The review findings indicate that each of these principles of justice provides a different perspective for a different benefit sharing rationale. For example, commutative justice provides a benefit sharing rationale that is focused on fair exchange of benefits between research sponsors and communities. Distributive justice produces a benefit sharing rationale that is focused on improving the health needs of the vulnerable research communities. We have suggested that a good benefit sharing framework particularly in global health research would be more beneficial if it combines all the principles of justice in its formulation. Nonetheless, there is a need for empirical studies to examine the various principles of justice and their nuances in benefit sharing among stakeholders in global health research. 相似文献
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To understand the impact of alternative translation initiation on a proteome, we performed a proteome‐wide study on protein turnover using positional proteomics and ribosome profiling to distinguish between N‐terminal proteoforms of individual genes. By combining pulsed SILAC with N‐terminal COFRADIC, we monitored the stability of 1,941 human N‐terminal proteoforms, including 147 N‐terminal proteoform pairs that originate from alternative translation initiation, alternative splicing or incomplete processing of the initiator methionine. N‐terminally truncated proteoforms were less abundant than canonical proteoforms and often displayed altered stabilities, likely attributed to individual protein characteristics, including intrinsic disorder, but independent of N‐terminal amino acid identity or truncation length. We discovered that the removal of initiator methionine by methionine aminopeptidases reduced the stability of processed proteoforms, while susceptibility for N‐terminal acetylation did not seem to influence protein turnover rates. Taken together, our findings reveal differences in protein stability between N‐terminal proteoforms and point to a role for alternative translation initiation and co‐translational initiator methionine removal, next to alternative splicing, in the overall regulation of proteome homeostasis. 相似文献
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Natalia G. Bednarska Johan van Eldere Rodrigo Gallardo Ashok Ganesan Meine Ramakers Isabel Vogel Pieter Baatsen An Staes Marc Goethals Per Hammarström K. Peter R. Nilsson Kris Gevaert Joost Schymkowitz Frederic Rousseau 《Molecular microbiology》2016,99(5):849-865
Taking advantage of the xenobiotic nature of bacterial infections, we tested whether the cytotoxicity of protein aggregation can be targeted to bacterial pathogens without affecting their mammalian hosts. In particular, we examined if peptides encoding aggregation‐prone sequence segments of bacterial proteins can display antimicrobial activity by initiating toxic protein aggregation in bacteria, but not in mammalian cells. Unbiased in vitro screening of aggregating peptide sequences from bacterial genomes lead to the identification of several peptides that are strongly bactericidal against methicillin‐resistant Staphylococcus aureus. Upon parenteral administration in vivo, the peptides cured mice from bacterial sepsis without apparent toxic side effects as judged from histological and hematological evaluation. We found that the peptides enter and accumulate in the bacterial cytosol where they cause aggregation of bacterial polypeptides. Although the precise chain of events that leads to cell death remains to be elucidated, the ability to tap into aggregation‐prone sequences of bacterial proteomes to elicit antimicrobial activity represents a rich and unexplored chemical space to be mined in search of novel therapeutic strategies to fight infectious diseases. 相似文献
979.
Nathalie Gonzalez Laurens Pauwels Alexandra Baekelandt Liesbeth De Milde Jelle Van Leene Nienke Besbrugge Ken S. Heyndrickx Amparo Cuéllar Pérez Astrid Nagels Durand Rebecca De Clercq Eveline Van De Slijke Robin Vanden Bossche Dominique Eeckhout Kris Gevaert Klaas Vandepoele Geert De Jaeger Alain Goossens Dirk Inzé 《The Plant cell》2015,27(8):2273-2287
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