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Minimal Variation (minimal + variation)
Selected AbstractsAn X-band 185° CMOS phase shifter MMIC for multiple-antenna systemsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2009Chien-San Lin Abstract The design and implementation of an X-band phase shifter MMIC using the standard 0.18-,m CMOS process is presented. A transformed doublet varactor load is analyzed and applied to a 3-dB quadrature coupler to exhibit large phase shift tuning range and low insertion loss with minimal variation. By using the derived design equations, the implemented CMOS reflection-type phase shifter demonstrates a continuous phase shift tuning range greater than 185°, an average insertion loss of 5.2 dB with ±0.4 dB variation, and return losses better than 13 dB in 9,11 GHz. The total chip size including I/O pads is 0.76 × 0.79 mm2. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 645,648, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24131 [source] Quantitative analysis of messenger RNA abundance for ribosomal protein L-15, cyclophilin-A, phosphoglycerokinase, ,-glucuronidase, glyceraldehyde 3-phosphate dehydrogenase, ,-actin, and histone H2A during bovine oocyte maturation and early embryogenesis in vitroMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2006AnilKumar Bettegowda Abstract Real-time reverse transcription PCR has greatly improved the ease and sensitivity of quantitative gene expression studies. However, measurement of gene expression generally requires selection of a valid reference (housekeeping gene) for data normalization to compensate for inherent variations. Given the dynamic nature of early embryonic development, application of this technology to studies of oocyte and early embryonic development is further complicated due to limited amounts of starting material and a paucity of information on constitutively expressed genes for data normalization. We have validated quantitative procedures for real-time reverse transcription polymerase chain reaction (RT-PCR) analysis of mRNA abundance during bovine meiotic maturation and early embryogenesis and utilized this technology to determine temporal changes in mRNA abundance for ribosomal protein L-15, cyclophilin-A, phosphoglycerokinase, ,-glucuronidase, glyceraldehyde-3-phosphate dehydrogenase, ,-actin, and histone H2A. Quantification of amounts of specific exogenous RNAs added to samples revealed acceptable rates of RNA recovery and efficiency of reverse transcription with minimal variation. Progression of bovine oocytes to metaphase II resulted in reduced abundance of polyadenylated, but not total transcripts for majority of above genes; however phosphoglycerokinase exhibited a significant decline in both RNA populations. Abundance of mRNAs for above genes in early embryos generally remained low until the blastocyst stage, but abundance of ribosomal protein L-15 mRNA was increased at the morula stage and histone H2A mRNA showed dynamic changes prior to embryonic genome activation. Results demonstrate a valid approach for quantitative analysis of mRNA abundance in oocytes and embryos, but do not support constitutive expression of above genes during early embryonic development. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc. [source] Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expressionNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2010V. Arechavala-Gomeza V. Arechavala-Gomeza, M. Kinali, L. Feng, S. C. Brown, C. Sewry, J. E. Morgan and F. Muntoni (2010) Neuropathology and Applied Neurobiology36, 265,274 Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression Aims: The quantification of protein levels in muscle biopsies is of particular relevance in the diagnostic process of neuromuscular diseases, but is difficult to assess in cases of partial protein deficiency, particularly when information on protein localization is required. The combination of immunohistochemistry and Western blotting is often used in these cases, but is not always possible if the sample is scarce. We therefore sought to develop a method to quantify relative levels of sarcolemma-associated proteins using digitally captured images of immunolabelled sections of skeletal muscle. Methods: To validate our relative quantification method, we labelled dystrophin and other sarcolemmal proteins in transverse sections of muscle biopsies taken from Duchenne muscular dystrophy and Becker muscular dystrophy patients, a manifesting carrier of Duchenne muscular dystrophy and normal controls. Results: Using this method to quantify relative sarcolemmal protein abundance, we were able to accurately distinguish between the different patients on the basis of the relative amount of dystrophin present. Conclusions: This comparative method adds value to techniques that are already part of the diagnostic process and can be used with minimal variation of the standardized protocols, without using extra amounts of valuable biopsy samples. Comparative quantification of sarcolemmal proteins on immunostained muscle sections will be of use to establish both the abundance and localization of the protein. Moreover, it can be applied to assess the efficacy of experimental therapies where only partial restoration or upregulation of the protein may occur. [source] Hearing Loss in Union Army Veterans from 1862 to 1920,THE LARYNGOSCOPE, Issue 12 2004Ryan K. Sewell MD Abstract Objectives: To examine the prevalence of hearing loss (HL) in Union Army (UA) veterans by year, birth cohort, and occupation, and to compare Civil War pension and contemporary disability programs by examining monthly dollar awards. Study Design: A retrospective review of medical records for 17,722 UA veteran pension applicants, a subset of some 35,000 soldiers retrieved randomly from the Military Archives. Methods: The diagnosis of HL was based on review of medical records, which used gross measurements because of the unavailability of audiometric testing. Results: One third (5,891 or 33%) of pensioners sampled received compensation for HL. The veterans with HL suffered predominantly from left-sided HL (4,091 or 70%), which is consistent with noise-induced HL in a right-handed individual firing a rifle. Comparison of civilian occupations reveals minimal variation in prevalence of HL. Civil War pensions for unilateral HL averaged $134.04 per year, representing nearly one third of the average annual income in 1890. Bilateral HL received nearly twice that amount. Today, military veterans receive $1,248 annually for unilateral loss and $27,288 annually for bilateral loss. Social Security disability benefits are granted only for bilateral HL, with an average 60-year-old individual receiving $11,400 per year. Conclusion: HL was a common disability among UA Civil War veterans, with noise exposure a likely etiology for the HL. The differing levels of compensation for HL may reflect differing perceptions on the incapacitating effects of HL. [source] Association between parasite infection and immune responses in multiple sclerosisANNALS OF NEUROLOGY, Issue 2 2007Jorge Correale MD Objective To assess whether parasite infection is correlated with a reduced number of exacerbations and altered immune reactivity in multiple sclerosis (MS). Methods A prospective, double-cohort study was performed to assess the clinical course and radiological findings in 12 MS patients presenting associated eosinophilia. All patients presented parasitic infections with positive stool specimens. In all parasite-infected MS patients, the eosinophilia was not present during the 2 previous years. Eosinophil counts were monitored at 3- to 6-month intervals. When counts became elevated, patients were enrolled in the study. Interleukin (IL)-4, IL-10, IL-12, transforming growth factor (TGF)-,, and interferon-, production by myelin basic protein,specific peripheral blood mononuclear cells were studied using enzyme-linked immunospot (ELISPOT). FoxP3 and Smad7 expression were studied by reverse-transcriptase polymerase chain reaction. Results During a 4.6-year follow-up period, parasite-infected MS patients showed a significantly lower number of exacerbations, minimal variation in disability scores, as well as fewer magnetic resonance imaging changes when compared with uninfected MS patients. Furthermore, myelin basic protein,specific responses in peripheral blood showed a significant increase in IL-10 and TGF-, and a decrease in IL-12 and interferon-,,secreting cells in infected MS patients compared with noninfected patients. Myelin basic protein,specific T cells cloned from infected subjects were characterized by the absence of IL-2 and IL-4 production, but high IL-10 and/or TGF-, secretion, showing a cytokine profile similar to the T-cell subsets Tr1 and Th3. Moreover, cloning frequency of CD4+CD25+ FoxP3+ T cells was substantially increased in infected patients compared with uninfected MS subjects. Finally, Smad7 messenger RNA was not detected in T cells from infected MS patients secreting TGF-,. Interpretation Increased production of IL-10 and TGF-,, together with induction of CD25+CD4+ FoxP3+ T cells, suggests that regulatory T cells induced during parasite infections can alter the course of MS. Ann Neurol 2007 [source] | ||||||||||