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Different Spanish unifloral honeys (eucalyptus, sunflower, rosemary, thyme, lavender, citrus, anise, quercus, and lemon blossom) and one multifloral honey were studied by Free-Choice Profiling (FCP) analysis. Generalized Procrustes Analysis (GPA) applied to the FCP data allowed discrimination between samples and provided information on the attributes responsible for the differences observed. The honeys had significantly different sensory characteristics. Textural attributes were the predominant factor in discriminating between samples, and appearance (color included) was also correlated with GPA dimensions to a lesser extent.  相似文献   
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Studies of sibling competition within brood hierarchies have rarely assessed simultaneously the effects of sex and rank in the brood hierarchy on traits other than offspring mortality and differential growth. We studied the expression of heat-shock proteins (Hsps) to assess the physiological stress response to different combinations of sex and position within competitive brood hierarchies in the black kite Milvus migrans (Bodd.), a sexually dimorphic raptor showing facultative siblicide. Senior males showed higher stress levels than did senior females and younger siblings of each sex as revealed by Hsp60 values. The analysis of Hsp70 levels indicated that nestlings from broods in which the senior chick was a male showed higher stress levels than did nestlings from broods in which the senior chick was a female. In addition, levels of Hsp60 were related negatively to nutritional condition expressed as levels of plasmatic albumin. This suggests that the sex of senior chicks may be key in determining their stress level and that of their siblings, which is probably associated with sibling competition by fighting within brood hierarchies. The comparatively higher stress levels of senior males (and their siblings) may be a consequence of their ability to exploit their potential advantage from being the head start while avoiding a possible competitive disadvantage from being the smaller sex, independent of environmental conditions determining the probability of brood reduction. Differential stress levels depending on sex and rank in the brood hierarchy may be a consequence of parental control of offspring behaviour through differential resource allocation (e.g. yolk androgens) or it may reflect adaptations of particular chicks (senior males) to enhance their competitive ability within brood hierarchies.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 383–390.  相似文献   
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Introduction  

Recently an association between a genetic variation in TRAF1/C5 and mortality from sepsis or cancer was found in rheumatoid arthritis (RA). The most prevalent cause of death, cardiovascular disease, may have been missed in that study, since patients were enrolled at an advanced disease stage. Therefore, we used an inception cohort of RA patients to investigate the association between TRAF1/C5 and cardiovascular mortality, and replicate the findings on all-cause mortality. As TRAF1/C5 associated mortality may not be restricted to RA, we also studied a large cohort of non-RA patients.  相似文献   
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Biogenic origin of the significant proportion of coal bed methane has indicated the role of microbial communities in methanogenesis. By using cultivation-independent approach, we have analysed the archaeal and bacterial community present in the formation water of an Indian coal bed at 600–700 m depth to understand their role in methanogenesis. Presence of methanogens in the formation water was inferred by epifluorescence microscopy and PCR amplification of mcrA gene. Archaeal 16S rRNA gene clone library from the formation water metagenome was dominated by methanogens showing similarity to Methanobacterium, Methanothermobacter and Methanolinea whereas the clones of bacterial 16S rRNA gene library were closely related to Azonexus, Azospira, Dechloromonas and Thauera. Thus, microbial community of the formation water consisted of predominantly hydrogenotrophic methanogens and the proteobacteria capable of nitrogen fixation, nitrate reduction and polyaromatic compound degradation. Methanogenic potential of the microbial community present in the formation water was elucidated by the production of methane in the enrichment culture, which contained 16S rRNA gene sequences showing close relatedness to the genus Methanobacterium. Microcosm using formation water as medium as well as a source of inoculum and coal as carbon source produced significant amount of methane which increased considerably by the addition of nitrite. The dominance of Diaphorobacter sp. in nitrite amended microcosm indicated their important role in supporting methanogenesis in the coal bed. This is the first study indicating existence of methanogenic and bacterial community in an Indian coal bed that is capable of in situ biotransformation of coal into methane.  相似文献   
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In the southern Iberian Peninsula, Rhododendron ponticum occurs in restricted and vulnerable populations as a Tertiary relict. Population structure and the main phases of the reproductive process were examined in order to shed light on recruitment patterns and limitations. Rhododendron ponticum flowers are self-compatible and attract a diverse array of insects, which are responsible for a considerable number of seeds set in the populations. Nevertheless, only adults form populations, whilst seedlings are scarce and saplings virtually absent (only two juveniles out of 2489 adults sampled). Non-specialized vegetative multiplication by layering was observed. Recruitment failure seems to depend on the scarcity of safe microsites, which are free from drought, for seedling establishment. The observations contrast with R. ponticum 's reputation as an aggressive invader in temperate Atlantic areas. It is proposed that the species shows a variable balance between sexual reproduction and vegetative multiplication depending on environmental conditions. At present, only the latter seems to be prevailing in relict populations in the Iberian Peninsula. This flexible reproductive strategy is also discussed as a mechanism allowing persistence during geological climatic oscillations.  © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 297–311.  相似文献   
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The enantiopure (1 S, 2 S )- cis -dihydrodiol metabolites 2B - 5B have been obtained in low yield from the corresponding monosubstituted halobenzene substrates 2A - 5A, using a wild-type strain of Pseudomonas putida (ML2) containing benzene dioxygenase (BDO). Benzene cis -dihydrodiol dehydrogenase (BCD) from P. putida ML2 and naphthalene cis -dihydrodiol dehydrogenase (NCD) from P. putida 8859 were purified and used in a comparative study of the stereoselective biotransformation of cis -dihydrodiol enantiomers 2B - 5B. The BCD and NCD enzymes were found to accept cis -dihydrodiol enantiomers of monosubstituted benzene cis -dihydrodiol substrates 2B - 5B of opposite absolute configuration. The acyclic alkene 1,2-diols 10 - 17 were also found to be acceptable substrates for BCD.  相似文献   
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Staphylococcus aureus is a major human pathogen, first recognized as a leading cause of hospital-acquired infections. Community-associated S. aureus (CA-SA) pose a greater threat due to increase in severity of infection and disease among children and healthy adults. CA-SA strains in India are genetically diverse, among which is the sequence type (ST) 772, which has now spread to Australia, Europe and Japan. Towards understanding the genetic characteristics of ST772, we obtained draft genome sequences of five relevant clinical isolates and studied the properties of their PVL-carrying prophages, whose presence is a defining hallmark of CA-SA. We show that this is a novel prophage, which carries the structural genes of the hlb-carrying prophage and includes the sea enterotoxin. This architecture probably emerged early within the ST772 lineage, at least in India. The sea gene, unique to ST772 PVL, despite having promoter sequence characteristics typical of low expression, appears to be highly expressed during early phase of growth in laboratory conditions. We speculate that this might be a consequence of its novel sequence context. The crippled nature of the hlb-converting prophage in ST772 suggests that widespread mobility of the sea enterotoxin might be a selective force behind its ‘transfer’ to the PVL prophage. Wild type ST772 strains induced strong proliferative responses as well as high cytotoxic activity against neutrophils, likely mediated by superantigen SEA and the PVL toxin respectively. Both proliferation and cytotoxicity were markedly reduced in a cured ST772 strain indicating the impact of the phage on virulence. The presence of SEA alongside the genes for the immune system-modulating PVL toxin may contribute to the success and virulence of ST772.  相似文献   
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