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991.
Within the framework of nutritional ecology, subsistence diversification is achieved by adding different species to a diet, but explanations for this diversification vary. In the Broad Spectrum Revolution approach, explanations include demographic, ecological, nutritional and technological factors, as well as the mobility of hunter-gatherer groups. The origin of small animal assemblages is a key issue underlying this debate, as these were an important food resource for several non-human predators (diurnal and nocturnal birds of prey and terrestrial carnivores). To establish the genesis of these accumulations, it is important to analyse the anatomical and age profiles of the animals, the bone breakage patterns and the bone surface modifications. With this aim, we present data from the Level IV faunal assemblage of Bolomor Cave (Valencia, Spain). Level IV, corresponding to MIS 5e, shows human use not only of small animals but also of large- and small-sized carnivores in addition to ungulates. Anthropogenic evidence includes cut-marks, intentional bone breakage, burning patterns and human tooth-marks. The utilisation of other less frequent animals could be related to a generalist human behaviour based on the exploitation of a broad range of prey, and could also be associated with an early diversification of the human diet in this locality. This study aims to provide data concerning human consumption of small prey, to establish the processing sequence both of large/medium and small animals and to contribute to the knowledge of human subsistence strategies in the European Middle Palaeolithic. 相似文献
992.
993.
A Nested Polymerase Chain Reaction Protocol for in planta Detection of Fusicladium eriobotryae,Causal Agent of Loquat Scab 下载免费PDF全文
Elisa González‐Domínguez Maela León Josep Armengol Mónica Berbegal 《Journal of Phytopathology》2015,163(5):415-418
Scab caused by the fungus Fusicladium eriobotryae is the most serious disease affecting loquat in Spain. Isolation of F. eriobotryae from infected tissue on culture media can be difficult due to its slow growth. A polymerase chain reaction (PCR)‐based protocol was developed for F. eriobotryae‐specific identification from pure culture or infected loquat tissues. The primer set was designed in the elongation factor 1‐α gene (EF1‐α), and specificity and sensitivity for single and nested PCR were validated. The nested PCR assay resulted in 100% positive detection of F. eriobotryae in naturally and artificially infected tissues. This protocol can be useful for routine diagnosis, disease monitoring programmes and epidemiological research. 相似文献
994.
995.
RNA viruses are known to replicate at very high mutation rates. These rates are actually known to be close to their so-called error threshold. This threshold is in fact a critical point beyond which genetic information is lost through a so-called error catastrophe. However, the transition from a stable quasispecies to genetic drift and loss of information can also occur by crossing replication thresholds, below some replication rates, the viral population is suddenly unable to survive. Available data from hepatitis C virus population analysis [Mas, A., Ulloa, E., Bruguera, M., Furci?, I., Garriga, D., Fábregas, S., Andreu, D., Saiz, J.C., Díez, J., 2004. Hepatitis C virus population analysis of a single-source nosocomial outbreak reveals an inverse correlation between viral load and quasispecies complexity. J. Gen. Virol. 85, 3619-3626] can be interpreted through this theoretical view, providing evidence for such a replication threshold. Here a simple model is used in order to provide evidence for such a phenomenon, consistent with available data. 相似文献
996.
Jun Lu Mischa Machius Irina Dulubova Han Dai Thomas C Südhof Diana R Tomchick Josep Rizo 《PLoS biology》2006,4(7)
C 2 domains are well characterized as Ca 2+/phospholipid-binding modules, but little is known about how they mediate protein–protein interactions. In neurons, a Munc13–1 C 2A-domain/RIM zinc-finger domain (ZF) heterodimer couples synaptic vesicle priming to presynaptic plasticity. We now show that the Munc13–1 C 2A domain homodimerizes, and that homodimerization competes with Munc13–1/RIM heterodimerization. X-ray diffraction studies guided by nuclear magnetic resonance (NMR) experiments reveal the crystal structures of the Munc13–1 C 2A-domain homodimer and the Munc13–1 C 2A-domain/RIM ZF heterodimer at 1.44 Å and 1.78 Å resolution, respectively. The C 2A domain adopts a β-sandwich structure with a four-stranded concave side that mediates homodimerization, leading to the formation of an eight-stranded β-barrel. In contrast, heterodimerization involves the bottom tip of the C 2A-domain β-sandwich and a C-terminal α-helical extension, which wrap around the RIM ZF domain. Our results describe the structural basis for a Munc13–1 homodimer–Munc13–1/RIM heterodimer switch that may be crucial for vesicle priming and presynaptic plasticity, uncovering at the same time an unexpected versatility of C 2 domains as protein–protein interaction modules, and illustrating the power of combining NMR spectroscopy and X-ray crystallography to study protein complexes. 相似文献
997.
998.
Josep M. Sierra Mariana Camoez Fe Tubau Oriol Gasch Miquel Pujol Rogelio Martin M. Angeles Domínguez 《PloS one》2013,8(3)
Linezolid is an effective antimicrobial agent to treat methicillin-resistant Staphylococcus aureus (MRSA). Resistance to linezolid due to the cfr gene is described worldwide. The present study aimed to analyze the prevalence of the cfr–mediated linezolid resistance among MRSA clinical isolates in our area. A very low prevalence of cfr mediated linezolid resistance was found: only one bacteremic isolate out of 2 215 screened isolates. The only linezolid resistant isolate arose in a patient, previously colonized by MRSA, following linezolid therapy. Despite the low rate of resistance in our area, ongoing surveillance is advisable to avoid the spread of linezolid resistance. 相似文献
999.
Rita Fernández-Hernández Marta Rafel Noel P Fusté Rafael S Aguayo Josep M Casanova Joaquim Egea Francisco Ferrezuelo Eloi Garí 《Cell cycle (Georgetown, Tex.)》2013,12(15):2510-2517
The function of Cyclin D1 (CycD1) has been widely studied in the cell nucleus as a regulatory subunit of the cyclin-dependent kinases Cdk4/6 involved in the control of proliferation and development in mammals. CycD1 has been also localized in the cytoplasm, where its function nevertheless is poorly characterized. In this work we have observed that in normal skin as well as in primary cultures of human keratinocytes, cytoplasmic localization of CycD1 correlated with the degree of differentiation of the keratinocyte. In these conditions, CycD1 co-localized in cytoplasmic foci with exocyst components (Sec6) and regulators (RalA), and with β1 integrin, suggesting a role for CycD1 in the regulation of keratinocyte adhesion during differentiation. Consistent with this hypothesis, CycD1 overexpression increased β1 integrin recycling and drastically reduced the ability of keratinocytes to adhere to the extracellular matrix. We propose that localization of CycD1 in the cytoplasm during skin differentiation could be related to the changes in detachment ability of keratinocytes committed to differentiation. 相似文献
1000.
Alberto Maceda-Veiga Josep Escribano-Alacid Adolfo de Sostoa Emili García-Berthou 《Biological invasions》2013,15(12):2707-2716
The aquarium trade has been identified as an important vector of aquatic invasive species but this question has mostly been investigated in North America. We investigated the variation in diversity and species composition in different trade types in southwestern Europe (three major international wholesalers, different retail store types, and local internet forums), mostly in Spain and Portugal. As in previous studies, the diversity of fishes in the aquarium trade was vast, with a total of 20 orders, 79 families, and 1,133 fish species detected in the trade types analyzed. 248 species were observed in a single metropolitan area (Barcelona), with estimates of about 294 species being present. International wholesalers had higher species richness and evenness, with a single one having over 700 species. General pet stores had much lower evenness but due to high turnover had a total richness of over 200 species. Internet forums had the lowest evenness but similar richness. The different commerce types varied significantly in relative species abundance with about a dozen of popular fish species (e.g., goldfish, Siamese fighting fish, common carp, guppy, swordtails) dominating the retail stores, particularly the general pet stores. Our results imply that frequency in the trade varies strongly among species and commerce types and although general pet stores have usually low diversity, this is compensated with a higher species turnover. Many of the most popular species are well known invasive species and some of the species available are temperate species that might establish in Europe, reinforcing the need for more careful implementation of education programs, regulation and monitoring of trade, and internalization of environmental costs by the industry. 相似文献