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Older Methods (older + methods)
Selected AbstractsGenetic estimates of contemporary effective population size in an endangered butterfly indicate a possible role for genetic compensationEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 1 2010Emily V. Saarinen Abstract The effective population size (Ne) is a critical evolutionary and conservation parameter that can indicate the adaptive potential of populations. Robust estimates of Ne of endangered taxa have been previously hampered by estimators that are sensitive to sample size. We estimated Ne on two remaining populations of the endangered Miami blue butterfly, a formerly widespread taxon in Florida. Our goal was to determine the consistency of various temporal and point estimators on inferring Ne and to determine the utility of this information for understanding the role of genetic stochasticity. We found that recently developed ,unbiased estimators' generally performed better than some older methods in that the former had more realistic Ne estimates and were more consistent with what is known about adult population size. Overall, Ne/N ratios based on census point counts were high. We suggest that this pattern may reflect genetic compensation caused by reduced reproductive variance due to breeding population size not being limited by resources. Assuming Ne and N are not heavily biased, it appears that the lack of gene flow between distant populations may be a greater genetic threat in the short term than the loss of heterozygosity due to inbreeding. [source] Coupling of mesh-free methods with finite elements: basic concepts and test resultsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 10 2006T. Rabczuk Abstract This paper reviews several novel and older methods for coupling mesh-free particle methods, particularly the element-free Galerkin (EFG) method and the smooth particle hydrodynamics (SPH), with finite elements (FEs). We study master,slave couplings where particles are fixed across the FE boundary, coupling via interface shape functions such that consistency conditions are satisfied, bridging domain coupling, compatibility coupling with Lagrange multipliers and hybrid coupling methods where forces from the particles are applied via their shape functions on the FE nodes and vice versa. The hybrid coupling methods are well suited for large deformations and adaptivity and the coupling procedure is independent of the particle distance and nodal arrangement. We will study the methods for several static and dynamic applications, compare the results to analytical and experimental data and show advantages and drawbacks of the methods. Copyright © 2006 John Wiley & Sons, Ltd. [source] Comparison of Commonly Used Assays for the Detection of MicroalbuminuriaJOURNAL OF CLINICAL HYPERTENSION, Issue 2004Douglas E. Busby MD There are a variety of methods for assessing urinary albumin excretion, extending from the very low-range microalbuminuria to higher ranges extending into macroalbuminuria or proteinuria. The recommendation for the initial screening of a new patient is to use a urine dipstick to assess for microalbuminuria. If positive, a spot urine for albumin:creatinine should be measured and reassessed annually. All patients with kidney disease, diabetes, or hypertension and metabolic syndrome should be screened for albuminuria. New methodologies using high-performance liquid chromatography are much more sensitive and specific when compared with older methods of detection and may prove very useful for earlier identification of high-risk patients. This is important since studies have shown that albuminuria levels below the microalbuminuria range, determined by conventional methodologies in uncomplicated essential hypertensive men, are associated with an adverse cardiovascular and metabolic risk profile. High performance liquid chromatography methodology, in contrast to older studies, detects all intact albumin and enables clinicians to assess disease severity and monitor therapeutic effectiveness with confidence in the accuracy of the microalbuminuria data reported to them. [source] Current trends in quantitative proteomicsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 12 2009Monica H. Elliott Abstract It was inevitable that as soon as mass spectrometrists were able to tell biologists which proteins were in their samples, the next question would be how much of these proteins were present. This has turned out to be a much more challenging question. In this review, we describe the multiple ways that mass spectrometry has attempted to address this issue, both for relative quantitation and for absolute quantitation of proteins. There is no single method that will work for every problem or for every sample. What we present here is a variety of techniques, with guidelines that we hope will assist the researcher in selecting the most appropriate technique for the particular biological problem that needs to be addressed. We need to emphasize that this is a very active area of proteomics research,new quantitative methods are continuously being introduced and some ,pitfalls' of older methods are just being discovered. However, even though there is no perfect technique,and a better technique may be developed tomorrow,valuable information on biomarkers and pathways can be obtained using these currently available methods Copyright © 2009 John Wiley & Sons, Ltd. [source] A simple and rapid technique for the detection of Epstein-Barr virus DNA in HIV-associated oral hairy leukoplakia biopsiesJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 3 2000M. J. E. M. F. Mabruk Abstract: A method of generating nucleic acid probes by polymerase chain reaction (PCR) for the detection of Epstein,Barr virus (EBV)-DNA by in situ hybridization in oral hairy leukoplakia (OHL) lesions is described. This method has the advantage over older methods of being cheaper, quicker and retaining sensitivity and specificity. Purified PCR products of Epstein-Barr virus DNA of 110 bp and 328 bp were labelled with biotin by nick translation or random primer labelling and were compared in in situ hybridization experiments with probes prepared by incorporation of biotin-labelled nucleotides in the PCR reaction mixture, with EBV viral DNA as a template. These probes were applied to 18 OHL tongue biopsies known to be positive for EBV-DNA, using a commercially available biotin-labelled BamHI "V" fragment EBV-DNA probe. To determine the specificity of the probes, we applied them to 20 normal tongue tissue samples and to 12 biopsies taken from keratotic tongue lesions from patients without risk factors for HIV infection and known to be negative for EBV-DNA. Clear positive signals for EBV-DNA were detected in all 18 cases of OHL biopsies using the amplimer of 328 bp labelled by PCR and random primer labelling. However, nick translation labelling was less efficient and sensitive. All control specimens were negative for EBV-DNA. [source] | ||||||||||