554 research outputs found
Keratinocyte Membrane-Associated Epidermal Cell-Derived Thymocyte-Activating Factor (ETAF)
This study describes the association between secreted keratinocyte interleukin 1 (IL-1) and its presence on the keratinocyte cell surface. These properties were studied in normal and transformed human keratinocytes as well as in transformed murine keratinocytes. we will present evidence that the secretion of IL-1 by human and murine keratinocytes is associated with the presence of IL-1 on the keratinocyte membrane. In addition, although transformed murine keratinocytes secrete other cytokines, namely keratinocyte T-cell growth factor (KTGF) and IL-3, no KTGF or IL-3 activity can be demonstrated on the cell surface
Adsorption of carbon dioxide on hydrotalcite-like compounds of different compositions
The adsorption of carbon dioxide on hydrotalcite-like compounds was investigated. Two different powdered hydrotalcites were used containing the cations nickel and iron. The powdered materials were screened for carbon dioxide adsorption using a thermogravimetric method and it was found that NiMgAl (Sample 1) hydrotalcite has the largest capacity for CO2, adsorbing 1.58 mmol g−1 at 20 °C, and highest rate of adsorption of up to 0.17 mmol g−1 min−1. This represented an increase of 53% in adsorption capacity, compared with NiMgAlFe (Sample 2). In order to improve the rheological behaviour of hydrotalcite paste for extrusion, hydrotalcite powders were combined with boehmite alumina (70:30 and 50:50 ratios of hydrotalcite:boehmite) before extrusion into pellets suitable for use in a fixed bed adsorber. These pellets were then re-crushed and further tested by thermogravimetric methods. The effects of temperature, composition and pre-treatment of the hydrotalcites on the adsorption of carbon dioxide and nitrogen are reported. At 20 °C, the amount of carbon dioxide adsorbed was between 2.0 and 2.5 mmol g−1 for all the hydrotalcite/alumina samples in this study, although this decayed rapidly with increasing temperature. The results are compared with silica gel as a common sorbent reference, and with literature values. Hydrotalcite/alumina samples have thermal stability and a high adsorption capacity for carbon dioxide over a wide range of temperatures. The composition of the hydrotalcite/alumina pellets investigated in this study has less effect upon the adsorption behaviour compared with the non-calcined hydrotalcite powder, thus allowing a wide choice of pellet compositions to be used
Diagnosis and management of functional tic-like phenomena
Over the past 3 years, a global phenomenon has emerged characterized by the sudden onset and frequently rapid escalation of tics and tic-like movements and phonations. These symptoms have occurred not only in youth known to have tics or Tourette syndrome (TS), but also, and more notably, in youth with no prior history of tics. The Tourette Association of America (TAA) convened an international, multidisciplinary working group to better understand this apparent presentation of functional neurological disorder (FND) and its relationship to TS. Here, we review and summarize the literature relevant to distinguish the two, with recommendations to clinicians for diagnosis and management. Finally, we highlight areas for future emphasis and research
Phase transitions in LaFeAsO: structural, magnetic, elastic, and transport properties, heat capacity and Mossbauer spectra
We present results from a detailed experimental investigation of LaFeAsO, the
parent material in the series of "FeAs" based oxypnictide superconductors. Upon
cooling this material undergoes a tetragonal-orthorhombic crystallographic
phase transition at ~160 K followed closely by an antiferromagnetic ordering
near 145 K. Analysis of these phase transitions using temperature dependent
powder X-ray and neutron diffraction measurements is presented. A magnetic
moment of ~0.35 Bohr magnetons per iron is derived from Mossbauer spectra in
the low temperature phase. Evidence of the structural transition is observed at
temperatures well above the structural transition (up to near 200 K) in the
diffraction data as well as the polycrystalline elastic moduli probed by
resonant ultrasound spectroscopy measurements. The effects of the two phase
transitions on the transport properties (resistivity, thermal conductivity,
Seebeck coefficient, Hall coefficient), heat capacity, and magnetization of
LaFeAsO are also reported, including a dramatic increase in the magnitude of
the Hall coefficient below 160 K. The results suggest that the structural
distortion leads to a localization of carriers on Fe, producing small local
magnetic moments which subsequently order antiferromagnetically upon further
cooling. Evidence of strong electron-phonon interactions in the
high-temperature tetragonal phase is also observed.Comment: Revised and expanded magnetization and Mossbauer spectroscopy
section. Clarified sample preparation description. This paper contains some
results from arXiv:0804.0796. 10 figure
Combined effects of time spent in physical activity, sedentary behaviors and sleep on obesity and cardio-metabolic health markers: a novel compositional data analysis approach
<div><p>The associations between time spent in sleep, sedentary behaviors (SB) and physical activity with health are usually studied without taking into account that time is finite during the day, so time spent in each of these behaviors are codependent. Therefore, little is known about the combined effect of time spent in sleep, SB and physical activity, that together constitute a composite whole, on obesity and cardio-metabolic health markers. Cross-sectional analysis of NHANES 2005–6 cycle on N = 1937 adults, was undertaken using a compositional analysis paradigm, which accounts for this intrinsic codependence. Time spent in SB, light intensity (LIPA) and moderate to vigorous activity (MVPA) was determined from accelerometry and combined with self-reported sleep time to obtain the 24 hour time budget composition. The distribution of time spent in sleep, SB, LIPA and MVPA is significantly associated with BMI, waist circumference, triglycerides, plasma glucose, plasma insulin (all p<0.001), and systolic (p<0.001) and diastolic blood pressure (p<0.003), but not HDL or LDL. Within the composition, the strongest positive effect is found for the proportion of time spent in MVPA. Strikingly, the effects of MVPA replacing another behavior and of MVPA being displaced by another behavior are asymmetric. For example, re-allocating 10 minutes of SB to MVPA was associated with a lower waist circumference by 0.001% but if 10 minutes of MVPA is displaced by SB this was associated with a 0.84% higher waist circumference. The proportion of time spent in LIPA and SB were detrimentally associated with obesity and cardiovascular disease markers, but the association with SB was stronger. For diabetes risk markers, replacing SB with LIPA was associated with more favorable outcomes. Time spent in MVPA is an important target for intervention and preventing transfer of time from LIPA to SB might lessen the negative effects of physical inactivity.</p></div
Designed, highly expressing, thermostable dengue virus 2 envelope protein dimers elicit quaternary epitope antibodies
Dengue virus (DENV) is a worldwide health burden, and a safe vaccine is needed. Neutralizing antibodies bind to quaternary epitopes on DENV envelope (E) protein homodimers. However, recombinantly expressed soluble E proteins are monomers under vaccination conditions and do not present these quaternary epitopes, partly explaining their limited success as vaccine antigens. Using molecular modeling, we found DENV2 E protein mutations that induce dimerization at low concentrations (\u3c100 pM) and enhance production yield by more than 50-fold. Cross-dimer epitope antibodies bind to the stabilized dimers, and a crystal structure resembles the wild-type (WT) E protein bound to a dimer epitope antibody. Mice immunized with the stabilized dimers developed antibodies that bind to E dimers and not monomers and elicited higher levels of DENV2-neutralizing antibodies compared to mice immunized with WT E antigen. Our findings demonstrate the feasibility of using structure-based design to produce subunit vaccines for dengue and other flaviviruses
Immunization for HIV-1 Broadly Neutralizing Antibodies in Human Ig Knockin Mice
A subset of individuals infected with HIV-1 develops broadly neutralizing antibodies (bNAbs) that can prevent infection, but it has not yet been possible to elicit these antibodies by immunization. To systematically explore how immunization might be tailored to produce them, we generated mice expressing the predicted germline or mature heavy chains of a potent bNAb to the CD4 binding site (CD4bs) on the HIV-1 envelope glycoprotein (Env). Immunogens specifically designed to activate B cells bearing germline antibodies are required to initiate immune responses, but they do not elicit bNAbs. In contrast, native-like Env trimers fail to activate B cells expressing germline antibodies but elicit bNAbs by selecting for a restricted group of light chains bearing specific somatic mutations that enhance neutralizing activity. The data suggest that vaccination to elicit anti-HIV-1 antibodies will require immunization with a succession of related immunogens
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Turf Management Club by John Traynor (page 1) Who Is Superintendent Here by H.E. Frenette (1) Good Turf Can Result from good Sodding (3) Golf Course Superintendent by Edwart Wiacek (4) Picture - Outstanding Senior Prof. Troll Picture - recognition for Blazers St. Andrew\u27s, Scotland by William Hynd (5) Analogy of a Turf Manager by James B. Cole (6) Fish Trouble by Peter A. Langelier and Dennis P. Leger (8) Square Rings by Robert P. McGuire (9) A Different Type of Course by Robert Hall (10) Literature by Pierre Coste (11) Weeds in Golf Course Turf and Their Control by John F. Cornman (A-1) The USe of Liquid Fertilizer by Anthony B. Longo (A-3) Fertilizing a Golf Course Through an Irrigation System by Herbert E. Berg (A-6) The Extent of Winter Injury on Golf Courses by James L. Holmes (A-11) The Problem of Winter Injury by James B. Beard (A-13) Establishing, Maintaining, and Selling Sod for Turf Areas in New England by George F. Stewart (A-20) Problems of Maintaining Turf Around Industrial Grounds by George Moore (A-22) Landscaping Industrial sites by A.W. Boicourt (A-25) Introduction to the panel Discussion on Grasses for Tees and Their Management by Alexander M. Radko (A-28) Building a Golf Tee by Phil Cassidy (A-29) Grasses for Tees and Their Management by Wm. Dest (A-31) Golf Course Tee maintenance by Jim Fulwider (A-32) Tees by F. Thompson (A-33) How to Draw up a Contract by Lawrence D. Rhoades (A-34) My Contract by Lucien E. Duval (A-37) The Golf Car Problem by Geoffrey S. Cornish (A-41) Golf Cars and Turfgrass by Lee Record (A-42) Course Design and Golf Cars by William F. Mitchell (A-42) Golf Cars and the Established Course by Sherwood Moore (A-45) Course Design and Golf Cars by Phil Wogan (a-52) Introduction of Cars to the New Course by M. Ovian (A-56
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