731 research outputs found
Genomic DNA isolation from Artemisia species grown in cold desert high altitude of India
Artemisia which produces a large number of secondary metabolites is naturally found in cold desert high altitude environment of India. Secondary metabolites such as alkaloids, flavonoids, phenols, polysaccharides and terpenes represent a significant barrier to the extraction of pure genomic DNA. Thus, in this study, the DNA extraction protocol to extract pure genomic DNA from different Artemisia species was tailored. The protocol was based on the CTAB method with slight modifications. In the study, 1.6 M NaCl, 2% cetyltrimethyl ammonium bromide (CTAB), 3% polyvinylpyrrolidone (PVP) and 0.5% β-mercaptoethanol was used in the extraction buffer. The incubation period was kept for 1 h at 65°C with one-tenth of the volume of warm (55°C) 10% CTAB solution during the extraction process. This study described a reliable protocol for extracting good quality and optimum amount of DNA from Artemisia species suitable for PCR analysis.Key words: Artemisia, genomic DNA isolation, PCR amplification, secondary metabolites
Analysis of genetic diversity in female, male and half sibs willow genotypes through RAPD and SSR markers
Willows belong to the genus Salix (Salicaceae) and consist of large number of species with large phenotypic variations. As a result, it has a low diagnostic value for identifying pure species and interspecific hybrids. Genetic characterization of 34 reference genotypes (4 female, 10 male, and 20 half sibs) of Salix collected from Naganji Nursery of University of Horticulture and Forestry, Solan, Himachal Pradesh, India were analyzed using 10 SSRs and 15 RAPDs PCR-based molecular markers. RAPD analysis yielded 87 polymorphic fragments (98.9%), with an average of 5.8 polymorphic fragments per primer. Similarly, SSR analysis produced 33 bands, out of which 26 were polymorphic (78.8%) with an average of 2.6 polymorphic fragments per primer. The genetic diversity was high among the genotypes (Nei’s genetic diversity = 0.468 and Shannon’s information index = 0.659) as measured by combination of both RAPD and SSR markers. The mean coefficient of gene differentiation (Gst) was 0.034, indicating 96.6% of the genetic diversity resided within the genotypes. The genetic diversity among genotypes of Salix sp. was found to be high, suggesting the importance and feasibility of introducing elite genotypes from different origins for Salix germplasm conservation and breeding programs.Keywords: Salix sp., half sibs, molecular markers, genomic DNA fingerprinting.African Journal of Biotechnology Vol. 12(29), pp. 4578-458
Recommended from our members
Gaussian Filtering for Simultaneously Occurring Delayed and Missing Measurements
Data Access Statement: This research did not use any experimentally generated data or data from any publicly available dataset. Model definitions (including the specified probability distributions) and parameter values (including the initialization parameters) provided in the paper are adequate for reproducing the exact qualitative behavior of the algorithms illustrated in the paper.© Copyright 2022 The Authors. Approximate filtering algorithms in nonlinear systems assume Gaussian prior and predictive density and remain popular due to ease of implementation as well as acceptable performance. However, these algorithms are restricted by two major assumptions: they assume no missing or delayed measurements. However, practical measurements are frequently delayed and intermittently missing. In this paper, we introduce a new extension of the Gaussian filtering to handle the simultaneous occurrence of the delay in measurements and intermittently missing measurements. Our proposed algorithm uses a novel modified measurement model to incorporate the possibility of the delayed and intermittently missing measurements. Subsequently, it redesigns the traditional Gaussian filtering for the modified measurement model. Our algorithm is a generalized extension of the Gaussian filtering, which applies to any of the traditional Gaussian filters, such as the extended Kalman filter (EKF), unscented Kalman filter (UKF), and cubature Kalman filter (CKF). A further contribution of this paper is that we study the stochastic stability of the proposed method for its EKF-based formulation. We compared the performance of the proposed filtering method with the traditional Gaussian filtering (particularly the CKF) and three extensions of the traditional Gaussian filtering that are designed to handle the delayed and missing measurements individually or simultaneously.10.13039/501100001409-Department of Science and Technology (DST), Government of India, through Innovation in Science Pursuit for Inspired Research (INSPIRE) Faculty Award (Grant Number: DST/INSPIRE/04/2018/000089
Role of Buffalo Production in Sustainable Development of Rural Regions
Rice is the main summer crop in Egypt. It is a cash exportable crop that provides a main source of income to the Egyptian farmers and the national econ- omy. However, the farmers used to burn the rice straw at the farm borders and violate the law that forbids such action, which causes socio-economic negative externalities due to the generated smoke from burning. The smoke generated from burning is straw produced as byproduct of cultivated around 0.75 million ha of rice crop in Egypt, causes social costs due to the probability of premature-mortality and morbidity of rural and urban individuals and livestock. To conduct an economic assessment of such negative externalities a field research was conducted. A targeted ration of chopped rice-straw mixed with dissolved urea and molasses at 2% and 3% of weight, respectively, was fed to buffalo-feeder calves for meat production at 40% of the S.E. of the daily ration with a concentrate feed mix of 60% S.E. Such ration was compared with a control ration of dray chopped rice straw with the same proportion of concentrate feed mix. Two feed-response models were estimated for comparison of the two rations on the growth of the buffalo feeder calves for meat production. The Cobb-Douglas response function was the best fitted form according to the economic logic, significance of estimated parameters and the magnitude of R-2. The study derived the production elasticity, marginal daily gain, the value of marginal product from both estimated feed response functions. The economic marketing weight that maximizes the gross margin above the feed costs was esti- mated under the response model of treat rice straw feeding plan (targeted ration). It reached around 518 Kg live weight, while under the control ration it was only around 384 Kg. The larger market weight of treated rice straw ration was due to higher production elasticity, faster marginal daily gain, better marginal feed con- version and higher palatability of the ration than the control one. Egypt imports of red meat reached about 600 million dollars, due to lack of sufficient feed supply that constrained expansion in red meat production. Therefore, providing treated rice straw feed would provide additional source of livestock feeds which would provide additional 80,000 tons’ carcass weight from fed buffalo calves, which currently are slaughtered as rearing veal calves (60-80 days old). The estimated income gener- ated from one buffalo fed calves reached 50% of the average annual per capita income in Egypt. Such program would also stop the social costs stems from probable premature death and/or morbidity of human and livestock when burning rice straw. The study presented a proposed institutional program to introduce such technology into Egyptian agricultural sector
Segmentation of epidermal tissue with histopathological damage in images of haematoxylin and eosin stained human skin.
Background: Digital image analysis has the potential to address issues surrounding traditional histological techniques including a lack of objectivity and high variability, through the application of quantitative analysis. A key initial step in image analysis is the identification of regions of interest. A widely applied methodology is that of segmentation. This paper proposes the application of image analysis techniques to segment skin tissue with varying degrees of histopathological damage. The segmentation of human tissue is challenging as a consequence of the complexity of the tissue structures and inconsistencies in tissue preparation, hence there is a need for a new robust method with the capability to handle the additional challenges materialising from histopathological damage.Methods: A new algorithm has been developed which combines enhanced colour information, created following a transformation to the L*a*b* colourspace, with general image intensity information. A colour normalisation step is included to enhance the algorithm's robustness to variations in the lighting and staining of the input images. The resulting optimised image is subjected to thresholding and the segmentation is fine-tuned using a combination of morphological processing and object classification rules. The segmentation algorithm was tested on 40 digital images of haematoxylin & eosin (H&E) stained skin biopsies. Accuracy, sensitivity and specificity of the algorithmic procedure were assessed through the comparison of the proposed methodology against manual methods.Results: Experimental results show the proposed fully automated methodology segments the epidermis with a mean specificity of 97.7%, a mean sensitivity of 89.4% and a mean accuracy of 96.5%. When a simple user interaction step is included, the specificity increases to 98.0%, the sensitivity to 91.0% and the accuracy to 96.8%. The algorithm segments effectively for different severities of tissue damage.Conclusions: Epidermal segmentation is a crucial first step in a range of applications including melanoma detection and the assessment of histopathological damage in skin. The proposed methodology is able to segment the epidermis with different levels of histological damage. The basic method framework could be applied to segmentation of other epithelial tissues
Groundwater Nitrogen Pollution and Assessment of Its Health Risks: A Case Study of a Typical Village in Rural-Urban Continuum, China
Protecting groundwater from nitrogen contamination is an important public-health concern and a major national environmental issue in China. In this study, we monitored water quality in 29 wells from 2009 to 2010 in a village in Shanghai city, whick belong to typical rural-urban continuum in China. The total N and NO3-N exhibited seasonal changes, and there were large fluctuations in NH4-N in residential areas, but without significant seasonal patterns. NO2-N in the water was not stable, but was present at high levels. Total N and NO3-N were significantly lower in residential areas than in agricultural areas. The groundwater quality in most wells belonged to Class III and IV in the Chinese water standard, which defines water that is unsuitable for human consumption. Our health risk assessments showed that NO3-N posed the greatest carcinogenic risk, with risk values ranging from 19×10−6 to 80×10−6, which accounted for more than 90% of the total risk in the study area
Synthesis of tenascin and laminin beta2 chain in human bronchial epithelial cells is enhanced by cysteinyl leukotrienes via CysLT1 receptor
<p>Abstract</p> <p>Background</p> <p>Cysteinyl leukotrienes (CysLTs) are key mediators of asthma, but their role in the genesis of airway remodeling is insufficiently understood. Recent evidence suggests that increased expression of tenascin (Tn) and laminin (Ln) β2 chain is indicative of the remodeling activity in asthma, but represents also an example of deposition of extracellular matrix, which affects the airway wall compliance. We tested the hypothesis that CysLTs affect production of Tn and Ln β2 chain by human bronchial epithelial cells and elucidated, which of the CysLT receptors, CysLT<sub>1 </sub>or CysLT<sub>2</sub>, mediate this effect.</p> <p>Methods</p> <p>Cultured BEAS-2B human bronchial epithelial cells were stimulated with leukotriene D<sub>4 </sub>(LTD<sub>4</sub>) and E<sub>4 </sub>(LTE<sub>4</sub>) and evaluated by immunocytochemistry, Western blotting, flow cytometry, and RT-PCR. CysLT receptors were differentially blocked with use of montelukast or BAY u9773.</p> <p>Results</p> <p>LTD<sub>4 </sub>and LTE<sub>4 </sub>significantly augmented the expression of Tn, whereas LTD<sub>4</sub>, distinctly from LTE<sub>4</sub>, was able to increase also the Ln β2 chain. Although the expression of CysLT<sub>2 </sub>prevailed over that of CysLT<sub>1</sub>, the up-regulation of Tn and Ln β2 chain by CysLTs was completely blocked by the CysLT<sub>1</sub>-selective antagonist montelukast with no difference between montelukast and the dual antagonist BAY u9773 for the inhibitory capacity.</p> <p>Conclusion</p> <p>These findings suggest that the CysLT-induced up-regulation of Tn and Ln β2 chain, an important epithelium-linked aspect of airway remodeling, is mediated predominantly by the CysLT<sub>1 </sub>receptor. The results provide a novel aspect to support the use of CysLT<sub>1 </sub>receptor antagonists in the anti-remodeling treatment of asthma.</p
TB treatment outcomes among TB-HIV co-infections in Karnataka, India: how do these compare with non-HIV tuberculosis outcomes in the province?
A unified approach to molecular epidemiology investigations: tools and patterns in California as a case study for endemic shigellosis
<p>Abstract</p> <p>Background</p> <p>Shigellosis causes diarrheal disease in humans from both developed and developing countries, and multi-drug resistance is an emerging problem. The objective of this study is to present a unified approach that can be used to characterize endemic and outbreak patterns of shigellosis using use a suite of epidemiologic and molecular techniques. The approach is applied to a California case study example of endemic shigellosis at the population level.</p> <p>Methods</p> <p>Epidemiologic patterns were evaluated with respect to demographics, multi-drug resistance, antimicrobial resistance genes, plasmid profiles, and pulsed-field gel electrophoresis (PFGE) fingerprints for the 43 <it>Shigella </it>isolates obtained by the Monterey region health departments over the two year period from 2004-2005.</p> <p>Results</p> <p>The traditional epidemiologic as well as molecular epidemiologic findings were consistent with endemic as compared to outbreak shigellosis in this population. A steady low level of cases was observed throughout the study period and high diversity was observed among strains. In contrast to most studies in developed countries, the predominant species was <it>Shigella flexneri </it>(51%) followed closely by <it>S. sonnei </it>(49%). Over 95% of <it>Shigella </it>isolates were fully resistant to three or more antimicrobial drug subclasses, and 38% of isolates were resistant to five or more subclasses. More than half of <it>Shigella </it>strains tested carried the <it>tetB</it>, <it>catA</it>, or <it>bla</it><sub>TEM </sub>genes for antimicrobial resistance to tetracycline, chloramphenicol, and ampicillin, respectively.</p> <p>Conclusion</p> <p>This study shows how epidemiologic patterns at the host and bacterial population levels can be used to investigate endemic as compared to outbreak patterns of shigellosis in a community. Information gathered as part of such investigations will be instrumental in identifying emerging antimicrobial resistance, for developing treatment guidelines appropriate for that community, and to provide baseline data with which to compare outbreak strains in the future.</p
Back-action Evading Measurements of Nanomechanical Motion
When performing continuous measurements of position with sensitivity
approaching quantum mechanical limits, one must confront the fundamental
effects of detector back-action. Back-action forces are responsible for the
ultimate limit on continuous position detection, can also be harnessed to cool
the observed structure, and are expected to generate quantum entanglement.
Back-action can also be evaded, allowing measurements with sensitivities that
exceed the standard quantum limit, and potentially allowing for the generation
of quantum squeezed states. We realize a device based on the parametric
coupling between an ultra-low dissipation nanomechanical resonator and a
microwave resonator. Here we demonstrate back-action evading (BAE) detection of
a single quadrature of motion with sensitivity 4 times the quantum zero-point
motion, back-action cooling of the mechanical resonator to n = 12 quanta, and a
parametric mechanical pre-amplification effect which is harnessed to achieve
position resolution a factor 1.3 times quantum zero-point motion.Comment: 19 pages (double-spaced) including 4 figures and reference
- …