2,334 research outputs found
Investigation of charge coupled device correlation techniques
Analog Charge Transfer Devices (CTD's) offer unique advantages to signal processing systems, which often have large development costs, making it desirable to define those devices which can be developed for general system's use. Such devices are best identified and developed early to give system's designers some interchangeable subsystem blocks, not requiring additional individual development for each new signal processing system. The objective of this work is to describe a discrete analog signal processing device with a reasonably broad system use and to implement its design, fabrication, and testing
Cosmological Implications of the Tetron Model of Elementary Particles
Based on a possible solution to the tetron spin problem, a modification of
the standard Big Bang scenario is suggested, where the advent of a spacetime
manifold is connected to the appearance of tetronic bound states. The metric
tensor is constructed from tetron constituents and the reason for cosmic
inflation is elucidated. Furthermore, there are natural dark matter candidates
in the tetron model. The ratio of ordinary to dark matter in the universe is
calculated to be 1:5.Comment: 23 page
Newly identified NO-sensor guanylyl cyclase/connexin 43 association is involved in cardiac electrical function
Background: Guanylyl cyclase, a heme-containing alpha 1 beta 1 heterodimer (GC1), produces cGMP in response to Nitric oxide (NO) stimulation. The NO-GC1-cGMP pathway negatively regulates cardiomyocyte contractility and protects against cardiac hypertrophy-related remodeling. We recently reported that the beta 1 subunit of GC1 is detected at the intercalated disc with connexin 43 (Cx43). Cx43 forms gap junctions (GJs) at the intercalated disc that are responsible for electrical propagation. We sought to determine whether there is a functional association between GC1 and Cx43 and its role in cardiac homeostasis.
Methods and Results: GC1 and Cx43 immunostaining at the intercalated disc and coimmunoprecipitation from membrane fraction indicate that GC1 and Cx43 are associated. Mice lacking the alpha subunit of GC1 (GC alpha 1 knockout mice) displayed a significant decrease in GJ function (dye-spread assay) and Cx43 membrane lateralization. In a cardiac-hypertrophic model, angiotensin II treatment disrupted the GC1-Cx43 association and induced significant Cx43 membrane lateralization, which was exacerbated in GC alpha 1 knockout mice. Cx43 lateralization correlated with decreased Cx43-containing GJs at the intercalated disc, predictors of electrical dysfunction. Accordingly, an ECG revealed that angiotensin II-treated GCa1 knockout mice had impaired ventricular electrical propagation. The phosphorylation level of Cx43 at serine 365, a protein-kinase A upregulated site involved in trafficking/assembly of GJs, was decreased in these models.
Conclusions: GC1 modulates ventricular Cx43 location, hence GJ function, and partially protects from electrical dysfunction in an angiotensin II hypertrophy model. Disruption of the NO-cGMP pathway is associated with cardiac electrical disturbance and abnormal Cx43 phosphorylation. This previously unknown NO/Cx43 signaling could be a protective mechanism against stress-induced arrhythmia
Common Supplements Found To Lower Circulating Inflammation Levels
Glucosamine and chondroitin are popular non-vitamin dietary supplements used for osteoarthritis. Long-term use is associated with lower incidence of colorectal and lung cancers and with lower mortality; however, the mechanism underlying these observations is unknown. In vitro and animal studies show that glucosamine and chondroitin inhibit NF-kB, a central mediator of inflammation, but no definitive trials have been done in healthy humans.We conducted a randomized, double-blind, placebo-controlled, cross-over study to assess the effects of glucosamine hydrochloride (1500 mg/d) plus chondroitin sulfate (1200 mg/d) for 28 days compared to placebo in 18 (9 men, 9 women) healthy, overweight (body mass index 25.0-32.5 kg/m2) adults, aged 20-55 y. We examined 4 serum inflammatory biomarkers: C-reactive protein (CRP), interleukin 6, and soluble tumor necrosis factor receptors I and II; a urinary inflammation biomarker: prostaglandin E2-metabolite; and a urinary oxidative stress biomarker: F2-isoprostane. Plasma proteomics on an antibody array was performed to explore other pathways modulated by glucosamine and chondroitin.Serum CRP concentrations were 23% lower after glucosamine and chondroitin compared to placebo (P = 0.048). There were no significant differences in other biomarkers. In the proteomics analyses, several pathways were significantly different between the interventions after Bonferroni correction, the most significant being a reduction in the "cytokine activity" pathway (P = 2.6 x 10-16), after glucosamine and chondroitin compared to placebo.Glucosamine and chondroitin supplementation may lower systemic inflammation and alter other pathways in healthy, overweight individuals. This study adds evidence for potential mechanisms supporting epidemiologic findings that glucosamine and chondroitin are associated with reduced risk of lung and colorectal cancer.ClinicalTrials.gov NCT01682694
The development of a Īµ-polycaprolactone (PCL) scaffold for CNS repair
Potential treatment strategies for the repair of spinal cord injury (SCI) currently favour a combinatorial approach incorporating several factors, including exogenous cell transplantation and biocompatible scaffolds. The use of scaffolds for bridging the gap at the injury site is very appealing although there has been little investigation into CNS neural cell interaction and survival on such scaffolds before implantation. Previously we demonstrated that aligned micro-grooves 12.5-25 Āµm wide on Īµ-polycaprolactone (PCL) promoted aligned neurite orientation and supported myelination. In this study we identify the appropriate substrate and its topographical features required for the design of a 3D scaffold intended for transplantation in SCI. Using an established myelinating culture system of dissociated spinal cord cells, recapitulating many of the features of the intact spinal cord, we demonstrate that astrocytes plated on the topography secrete soluble factors(s) that delay oligodendrocyte differentiation but do not prevent myelination. However, as myelination does occur after a further 10-12 days in culture this does not prevent the use of PCL as a scaffold material as part of a combined strategy for the repair of SCI
Toward a Designable Extracellular Matrix: Molecular Dynamics Simulations of an Engineered Laminin-mimetic, Elastin-like Fusion Protein
Native extracellular matrices (ECMs), such as those of the human brain and
other neural tissues, exhibit networks of molecular interactions between
specific matrix proteins and other tissue components. Guided by these naturally
self-assembling supramolecular systems, we have designed a matrix-derived
protein chimera that contains a laminin globular-like (LG) domain fused to an
elastin-like polypeptide (ELP). All-atom, classical molecular dynamics
simulations of our designed laminin-elastin fusion protein reveal
temperature-dependent conformational changes, in terms of secondary structure
composition, solvent accessible surface area, hydrogen bonding, and surface
hydration. These properties illuminate the phase behavior of this fusion
protein, via the emergence of -sheet character in
physiologically-relevant temperature ranges.Comment: 53 pages, 7 figures in the main text; Supporting Information contains
1 table, 12 figures, 4 trajectory animations (videos
Heated IntraPEritoneal Chemotherapy (HIPEC) for Patients With Recurrent Ovarian Cancer A Systematic Literature Review
Emotional Intelligence: Comparative Analysis of Accounting and Non-Accounting Business Majors at Two Universities
Success in accounting has long been associated with completing technical tasks as opposed to cultivating relationships. In 1999, the AICPA Core Competency Framework was adopted and expanded professional competencies to include not only functional competencies but personal and broad-based business competencies. Personal competencies include intrapersonal and interpersonal skills, comprising a range of behaviors collectively grouped as emotional intelligence. This study examines the emotional intelligence (āEIā) of 609 business school students at 2 different universities (University A and B), using TTIās Emotional Quotient (TTI) inventory report. The groups were segregated into accounting and non-accounting groups and comparative t-tests were conducted.Ā The results were significant, confirming our hypotheses that the EI of accounting students at universities A and B, separately and combined, were lower than the EI scores of non-accounting business majors
Retrospective Analysis of Graduatesā Outcomes in a Post-Professional Occupational Therapy Doctorate Program
There are limited studies within occupational therapy literature assessing the outcomes of advanced degrees. Specifically, there is a scarcity of literature about the benefits of completing a post-professional occupational therapy doctorate (POTD) program. The purpose of this study was to retrospectively examine graduatesā professional and personal outcomes at a midwestern university with an established POTD program. A total of 64 graduate exit surveys completed by POTD graduates between the years of 2008 and 2017 were analyzed using a mixed methods research design. Emergent categories from the data included a greater sense of self-empowerment and confidence, expanded career opportunities, and increased professional knowledge and skills. Quantitative data indicated new employment opportunities and increased pay. Overall, graduates reported increased personal and professional growth, however continued research regarding the benefits of completing a POTD is needed to help guide occupational therapists considering an advanced degree
Role of impact parameter in branching reactions: Chemical accelerator studies of the reaction Xe++CH4āXeCH3 ++H
This is the publisher's version, also available electronically from http://scitation.aip.org/content/aip/journal/jcp/74/9/10.1063/1.441716.Integral reaction cross sections and product velocity distributions have been measured for the ionāmolecule reaction Xe+(CH4,H)XeCH3 + over the relative reactant translational energy range of 0.7ā5.5 eV by chemical accelerator techniques. The kinematic results indicate that reaction proceeds in a direct manner by a rebound mechanism over the energy range studied, suggesting that this substitution reaction occurs predominantly in small impact parameter collisions. This finding contrasts with the results obtained for the competing reaction, Xe+(CH4,CH3)XeH+, where the strong forward scattering of the XeH+ product indicates that Hāatom abstraction occurs primarily in large impact parameter collisions
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