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991.
Dyeing Plants and Knowledge Transfer in the Yungas Communities of Northwest Argentina. In the Yungas region of the Salta province, Argentina, interest in the use of plant dyes has revived due to new market demands
and the growth of rural tourism. In this study we compare the use of dyeing plants recorded between 1994 and 2000 with those
used in 2007 and 2008. We also address factors currently involved in the acquisition and transmission of knowledge. We worked
with 39 randomly chosen participants (of which 11 were artisans) in the first stage, and 32 artisans in the second stage.
Information was gathered during semi–structured interviews and structured questionnaires. Eleven and 57 dye plant species,
and 10 and 2 mordants, were registered in the first and second stage, respectively. The use of soft plant parts has increased,
relative to the employment of roots and barks. Pastels predominate among the colors obtained. Mothers are the main transmitters
of this knowledge; however, new mechanisms of knowledge acquisition and transfer are gaining importance. These results provide
an alternative for the diversification and quality of existing crafts. 相似文献
992.
Landa María Silvina García Silvia Inés Schuman Mariano Luis Peres Diaz Ludmila Soledad Aisicovich Maia Pirola Carlos José 《Journal of physiology and biochemistry》2020,76(4):599-608
Journal of Physiology and Biochemistry - Thyrotropin-releasing hormone (TRH) plays several roles as a hormone/neuropeptide. Diencephalic TRH (dTRH) participates in the regulation of blood pressure... 相似文献
993.
994.
Molecular phylogeny of the four Korean Ephemera species, Ephemera orientalis, E. sachalinensis, E. strigata, and E. separigata, was inferred from 630 bp sequences of the partial mitochondrial cytochrome c oxidase I (COI) gene. Results indicated that mean intraspecific sequence divergences were 0.70%, whereas mean interspecific divergences were 15.75%, and 17 samples were distinguished to four species correctly by COI sequences. The results also demonstrated that four species of Korean Ephemera assembled a monophyletic group with high support in maximum parsimony and maximum likelihood analyses. This Ephemera group was divided into two major clades of E. orientalis–E. sachalinensis and E. strigata–E. separigata. Furthermore, we demonstrated that this phylogeny explained altitudinal and habitat adaptations of Korean Ephemera species. The E. orientalis–E. sachalinensis clade, a widespread and lowland‐adapted mayfly group, retained plesiomorphic traits such as paired stripes on abdominal segments and was regarded as plesiotypic in terms of habitat adaptation, compared to the geographically more limited and upland‐adapted E. strigata–E. separigata clade. 相似文献
995.
Inés Moret Dolors Sánchez-Izquierdo Marisa Iborra Luis Tortosa Ana Navarro-Puche Pilar Nos José Cervera Belén Beltrán 《PloS one》2013,8(12)
The first step in biomarkers discovery is to identify the best protocols for their purification and analysis. This issue is critical when considering peripheral blood samples (plasma and serum) that are clinically interesting but meet several methodological problems, mainly complexity and low biomarker concentration. Analysis of small molecules, such as circulating microRNAs, should overcome these disadvantages. The present study describes an optimal RNA extraction method of microRNAs from human plasma samples. Different reagents and commercially available kits have been analyzed, identifying also the best pre-analytical conditions for plasma isolation. Between all of them, the column-based approaches were shown to be the most effective. In this context, miRNeasy Serum/Plasma Kit (from Qiagen) rendered more concentrated RNA, that was better suited for microarrays studies and did not require extra purification steps for sample concentration and purification than phenol based extraction methods. We also present evidences that the addition of low doses of an RNA carrier before starting the extraction process improves microRNA purification while an already published carrier dose can result in significant bias over microRNA profiles. Quality controls for best protocol selection were developed by spectrophotometry measurement of contaminants and microfluidics electrophoresis (Agilent 2100 Bioanalyzer) for RNA integrity. Selected donor and patient plasma samples and matched biopsies were tested by Affymetrix microarray technology to compare differentially expressed microRNAs. In summary, this study defines an optimized protocol for microRNA purification from human blood samples, increasing the performance of assays and shedding light over the best way to discover and use these biomarkers in clinical practice. 相似文献
996.
997.
Raquel González Inácio Mandomando Victoria Fumadó Charfudin Sacoor Eusébio Macete Pedro L. Alonso Clara Menendez 《PloS one》2013,8(11)
Background
Human milk and infant gut microbiota are essential for the immune system maturation and protection against infections. There is scarce information on the microbiological composition of breast milk in general, and none from developing countries. The objective of the study was to characterize the breast milk and gut microbiota from mothers and infants from southern Mozambique, where infections and breastfeeding are prevalent.Methods
A community-based study was undertaken among 121 pairs of women and infants. Breast milk and infant''s faeces were analyzed by bacterial culture and molecular methods. Breast milk samples were screened for HIV RNA by RT-PCR.Results
The most frequent bacterial groups isolated by culture media in breast milk were Staphylococci (96.4%), Streptococci (92.7%) and Lactobacilli (56.4%). HIV RNA was detected in 24% of the samples. Staphylococcus hominis, S. aureus, and S.parasanguis were more frequently isolated in infants ≤14 days of life. Women on exclusive breastfeeding presented higher proportion of S. parasanguis in breast milk than those on mixed infant feeding (36.4% versus 11.1%, p = 0.035). Bacterial diversity (mean number of bacterial species isolated by sample: 10.4 versus 8.5; p = 0.004) and the frequency of Lactobacillus spp (75.9% versus 36%, p = 0.003) were higher in the specimens with HIV RNA than in those without it. The main bacterial groups found in infant''s faeces were Bifidobacterium, Streptococci and Enterococci.Conclusions
Women with HIV RNA in breast milk had a different pattern of microbiological composition, suggesting specific immunopathological phenomena in HIV-infected women. Both breast milk and faecal microbiota composition varied with lactation period, which might be related to changes in the type of feeding over time and/or in the milk''s biochemical characteristics. These findings provide insights into interactions between commensal bacteria and HIV infection in human milk and the role of these bacteria in mucosal protection against infections in breastfed infants. 相似文献998.
Hye Suck An Jang Wook Lee Woo Jin Kim Hyun Jeong Lim Eun Mi Kim Soon Gyu Byun Young Baek Hur Jung Youn Park Jeong In Myeong Chul Min An 《Genes & genomics.》2013,35(6):805-815
The Pacific oyster, Crassostrea gigas, is the most important and valuable commercial fishery species in Korea. Its farming started 20 years ago and is still rapid expansion in Korea. In this study, to maintain the genetic diversity of this valuable marine resource, possible genetic similarity and differences between the wild population and hatchery population in Tongyeong, Korea were accessed using multiplex assays with nine highly polymorphic microsatellite loci. A total of 250 different alleles were found over all loci. Despite a long history of hatchery practices, very high levels of polymorphism (mean alleles = 22.89 and mean heterozygosity = 0.92) were detected between the two populations. No statistically significant reductions were found in heterozygosity or allelic diversity in the hatchery population compared with the wild population. However, significant genetic heterogeneity was found between two populations. These results provide no evidence to show that hatchery practice of Pacific oyster in Korea has significantly affected the genetic variability of the hatchery stock. Although further studies are needed for comprehensive determinations of the hatchery and wild populations with increased number of Pacific oyster sample collections, information on the genetic variation and differentiation obtained in this study can be applied for genetic monitoring of aquaculture stocks, genetic improvement by selective breeding and designing of more efficient conservation management guidelines for these valuable genetic materials. 相似文献
999.
Hye Suck An Jang Wook Lee Seong Wan Hong Ha Neui Hong Jung Youn Park Jeong In Myeong Chul Min An 《Genes & genomics.》2013,35(6):709-717
Red sea cucumber Stichopus japonicus is the most important and valuable commercial sea cucumber species in Korea. Its farming and stock enhancement started in the early 2000s and is still rapid expansion in Korea. Therefore, the analyses of genetic status of wild and hatchery populations are necessary to maintain the genetic diversity of this valuable marine resource. In this study, possible genetic similarity and differences between the wild population and hatchery population in Jeju, Korea were accessed using multiplex assays with eight highly polymorphic microsatellite loci. High levels of polymorphism were observed between the two populations. A total of 93 different alleles were found. Although a considerable loss of unique alleles and relatively high inbreeding coefficient value were observed in the hatchery samples, no statistically significant reductions were found in heterozygosity or allelic diversity in the hatchery population, compared with the wild population. However, significant genetic heterogeneity was found between two populations. These results suggest that genetic drift has probably promoted differentiation between populations, and stocking intensity in wild populations may correlate with loss of genetic integrity. Therefore, the sustainable exploitation plans of the fishery resource should be developed by applying basic genetic principles combined with molecular monitoring. This genetic baseline information of Korean red sea cucumber has important implications for designing of genetically sustainable restocking programs and more efficient conservation management guidelines for these valuable genetic materials. 相似文献
1000.
Inés Ibáñez Elise S. Gornish Lauren Buckley Diane M. Debinski Jessica Hellmann Brian Helmuth Janneke HilleRisLambers Andrew M. Latimer Abraham J. Miller‐Rushing Maria Uriarte 《Ecology and evolution》2013,3(1):170-181
Natural resources managers are being asked to follow practices that accommodate for the impact of climate change on the ecosystems they manage, while global‐ecosystems modelers aim to forecast future responses under different climate scenarios. However, the lack of scientific knowledge about short‐term ecosystem responses to climate change has made it difficult to define set conservation practices or to realistically inform ecosystem models. Until recently, the main goal for ecologists was to study the composition and structure of communities and their implications for ecosystem function, but due to the probable magnitude and irreversibility of climate‐change effects (species extinctions and loss of ecosystem function), a shorter term focus on responses of ecosystems to climate change is needed. We highlight several underutilized approaches for studying the ecological consequences of climate change that capitalize on the natural variability of the climate system at different temporal and spatial scales. For example, studying organismal responses to extreme climatic events can inform about the resilience of populations to global warming and contribute to the assessment of local extinctions. Translocation experiments and gene expression are particular useful to quantitate a species' acclimation potential to global warming. And studies along environmental gradients can guide habitat restoration and protection programs by identifying vulnerable species and sites. These approaches identify the processes and mechanisms underlying species acclimation to changing conditions, combine different analytical approaches, and can be used to improve forecasts of the short‐term impacts of climate change and thus inform conservation practices and ecosystem models in a meaningful way. 相似文献