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Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献
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R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
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The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
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Matrix metalloproteinases (MMPs) degrade components of the extracellular matrix of the disc, but the presence of MMP-19 has not been explored. In other tissues, MMP-19 is known to act in proteolysis of the insulin-like growth factor (IGF) binding protein-3, thereby exposing this protein to make it available to influence cell behavior. MMP-19 also has been shown to inhibit capillary-like formation and thus play a role in the avascular nature of the disc. Using immunohistochemistry, normal discs from six subjects aged newborn through 10 years and 20 disc specimens from control donors or surgical patients aged 15-76 (mean age 40.2 years) were examined for immunolocalization of MMP-19; six Thompson grade I discs, five Thompson grade II, eight Thompson grade III, five Thompson grade IV, and one Thompson grade V discs were analyzed. The results indicate that in discs from young subjects, MMP-19 was uniformly localized in the outer annulus. In discs from adult donors and surgical patients, outer and inner annulus cells only occasionally showed MMP-19 localization. The greatest expression of MMP-19 was observed in young discs, and little expression was seen in older or degenerating discs. Because MMP-19 has been shown to regulate IGF-mediated proliferation in other tissues, its decline in the aging/degenerating disc may contribute to the age-related decrease in disc cell numbers. 相似文献
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Ritha JA Njau Don de Savigny Lucy Gilson Eleuther Mwageni Franklin W Mosha 《Malaria journal》2009,8(1):1-27
Background
In the past decade there has been increasing visibility of malaria control efforts at the national and international levels. The factors that have enhanced this scenario are the availability of proven interventions such as artemisinin-based combination therapy, the wide scale use of insecticide-treated nets (ITNs) and a renewed emphasis in indoor residual house-spraying. Concurrently, there has been a window of opportunity of financial commitments from organizations such as the Global Fund for HIV/AIDS, Tuberculosis and Malaria (GFATM), the President's Malaria Initiative and the World Bank Booster programme.Methods
The case study uses the health policy analysis framework to analyse the implementation of a public-private partnership approach embarked upon by the government of Tanzania in malaria control – 'The Tanzania National Voucher Scheme'- and in this synthesis, emphasis is on the challenges faced by the scheme during the pre-implementation (2001 – 2004) and implementation phases (2004 – 2005). Qualitative research tools used include: document review, interview with key informants, stakeholder's analysis, force-field analysis, time line of events, policy characteristic analysis and focus group discussions. The study is also complemented by a cross-sectional survey, which was conducted at the Rufiji Health Demographic Surveillance Site, where a cohort of women of child-bearing age were followed up regarding access and use of ITNs.Results
The major challenges observed include: the re-introduction of taxes on mosquito nets and related products, procurement and tendering procedures in the implementation of the GFATM, and organizational arrangements and free delivery of mosquito nets through a Presidential initiative.Conclusion
The lessons gleaned from this synthesis include: (a) the consistency of the stakeholders with a common vision, was an important strength in overcoming obstacles, (b) senior politicians often steered the policy agenda when the policy in question was a 'crisis event', the stakes and the visibility were high, (c) national stakeholders in policy making have an advantage in strengthening alliances with international organizations, where the latter can become extremely influential in solving bottlenecks as the need arises, and (d) conflict can be turned into an opportunity, for example the Presidential initiative has inadvertently provided Tanzania with important lessons in the organization of 'catch-up' campaigns. 相似文献9.
JA Nboyine S Boyer D Saville MJ Smith SD Wratten 《New Zealand journal of zoology.》2016,43(4):336-350
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation. 相似文献
10.
An Ustilago maydis ergosterol biosynthesis mutant (A14) which is partially blocked in sterol 14alpha-demethylase (P45014DM) activity is described. This mutant accumulated the abnormal 14alpha-methyl sterols, eburicol, 14alpha-methylfecosterol, and obtusifoliol, along with significant amounts of ergosterol. Although the A14 mutant grew nearly as well as the wild type, it was impaired in cell extension growth, which indicated a dysfunction in apical cell wall synthesis. The mutant was also found to be hypersensitive to the azole fungicides penconazole and tebuconazole. 相似文献