CD4+CD25+ T regulatory cells from FIV+ cats induce a unique anergic profile in CD8+ lymphocyte targets

Abstract Background Using the FIV model, we reported previously that CD4+CD25+ T regulatory (Treg) cells from FIV+ cats are constitutively activated and suppress CD4+CD25- and CD8+ T cell immune responses. In an effort to further explore Treg-mediated suppression, we asked whether Treg cells induce anergy through the alteration of production of cyclins, cyclin-dependent kinases and their inhibitors. Results Lymphocytes were obtained from control or FIV+ cats and sorted by FACS into CD4+CD25+ and CD8+ populations. Following co-culture with CD4+CD25+ cells, CD8+ targets were examined by Western blot for changes in cyclins D3, E and A, retinoblastoma (Rb) protein, as well as the cyclin dependent kinase inhibitor p21cip1. Following co-culture with CD4+CD25+cells, we observed up-regulation of p21cip1 and cyclin E, with down-regulation of cyclin D3, in CD8+ cells from FIV+ cats. As expected, CD8+ targets from control cats were quiescent with little up-regulation of p21cip1 and cyclin E. There was also a lack of Rb phosphorylation in CD8+ targets consistent with late G1 cell cycle arrest. Further, IL-2 mRNA was down regulated in CD8+ cells after co-culture with CD4+CD25+ Treg cells. Following CD4+CD25+ co-culture, CD8+ targets from FIV+ cats also had increased Foxp3 mRNA expression; however, these CD8+Foxp3+ cells did not exhibit suppressor function. Conclusions Collectively, these data suggest that CD4+CD25+ Treg cells from FIV+ cats induce CD8+ anergy by disruption of normal G1 to S cell cycle progression.</p

Compression load failure of aluminum plates due to fire

An experimental study was performed to quantify the response and failure of 5083-H116 and 6082-T6 aluminum plates under compression load while being subjected to a constant heat flux representing a fire exposure. Using an intermediate scale loading frame with integrated heating, the study evaluated the effects of geometry, aluminum type, fire exposure, load, and fire protection. Intermediate scale aluminum panels which were more than 0.7 m high and 0.2 m wide were used to gain insights into the structural behavior of large structural sections exposed to fire. Failure temperatures were measured to range from 100 to 480 C and were dependent on applied stress and aluminum type. This indicates that the use of a single temperature criterion in fire resistance without load as typically done is not sufficient for evaluating structural response during fire. An empirical failure model was developed to account for fire exposure conditions, aluminum type, and geometr

Dielectronic Resonance Method for Measuring Isotope Shifts

Longstanding problems in the comparison of very accurate hyperfine-shift measurements to theory were partly overcome by precise measurements on few-electron highly-charged ions. Still the agreement between theory and experiment is unsatisfactory. In this paper, we present a radically new way of precisely measuring hyperfine shifts, and demonstrate its effectiveness in the case of the hyperfine shift of $4s\_{1/2}$ and $4p\_{1/2}$ in $^{207}\mathrm{Pb}^{53+}$. It is based on the precise detection of dielectronic resonances that occur in electron-ion recombination at very low energy. This allows us to determine the hyperfine constant to around 0.6 meV accuracy which is on the order of 10%

Statistical Procedures for Evaluating Daily and Monthly Hydrologic Model Predictions

The overall study objective was to evaluate the applicability of different qualitative and quantitative methods for comparing daily and monthly SWAT computer model hydrologic streamflow predictions to observed data, and to recommend statistical methods for use in future model evaluations. Statistical methods were tested using daily streamflows and monthly equivalent runoff depths. The statistical techniques included linear regression, Nash-Sutcliffe efficiency, nonparametric tests, t-test, objective functions, autocorrelation, and cross-correlation. None of the methods specifically applied to the non-normal distribution and dependence between data points for the daily predicted and observed data. Of the tested methods, median objective functions, sign test, autocorrelation, and cross-correlation were most applicable for the daily data. The robust coefficient of determination (CD*) and robust modeling efficiency (EF*) objective functions were the preferred methods for daily model results due to the ease of comparing these values with a fixed ideal reference value of one. Predicted and observed monthly totals were more normally distributed, and there was less dependence between individual monthly totals than was observed for the corresponding predicted and observed daily values. More statistical methods were available for comparing SWAT model-predicted and observed monthly totals. The 1995 monthly SWAT model predictions and observed data had a regression Rr2 of 0.70, a Nash-Sutcliffe efficiency of 0.41, and the t-test failed to reject the equal data means hypothesis. The Nash-Sutcliffe coefficient and the Rr2 coefficient were the preferred methods for monthly results due to the ability to compare these coefficients to a set ideal value of one

Bankfull Hydraulic Geometry Relationships for the Inner and Outer Bluegrass Regions of Kentucky

Bankfull hydraulic geometry relationships relate bankfull stream dimensions, such as cross-sectional area, width, mean depth, mean velocity, width to depth ratio, and slope to bankfull discharge. These relationships can assist in determining a design discharge for stream restoration and management projects. This study assessed 27 stable streams located in the Inner Bluegrass and Outer Bluegrass regions of Kentucky. Reaches were selected based on the presence of a U.S. Geological Survey gage, as well as other conditions such as presence of readily identifiable bankfull indicators, stability indices, and site accessibility. Bankfull channel dimensions and discharges were determined, and hydraulic geometry relationships were developed for both the Inner Bluegrass and Outer Bluegrass regions. These scaling relationships for karst-influenced streams were similar to others reported in the literature for non-karst areas. Significant differences between the regions were found only for bankfull width and width-to-depth ratio. Streams in the Inner Bluegrass tended to be more narrow and deep at bankfull discharges less than 10 m3s−1 and wider and shallower at bankfull discharges greater than 20 m3s−1 as compared to stream in the Outer Bluegrass. It is suspected that physiographic conditions related to local geology and/or riparian vegetation at three sites in the Outer Bluegrass accounted for these differences. Results of this study indicate that in instances of geologic variation within a physiographic region, hydraulic geometry relationships may require evaluation at the watershed scale

Magnetostriction of ternary Fe–Ga–X (X = C,V,Cr,Mn,Co,Rh) alloys

Binary iron-gallium (Galfenol) alloys have large magnetostrictions over a wide temperature range. Single crystal measurements show that additions of 2 at. % or greater of 3d and 4d transition elements with fewer (V, Cr, Mo, Mn) and more (Co, Ni, Rh) valence electrons than Fe, all reduce the saturation magnetostriction. Kawamiya and Adachi [J. Magn. Magn. Mater. 31–34, 145 (1983)] reported that the D03 structure is stabilized by 3dtransition elements with electron∕atom ratios both less than iron and greater than iron. IfD03 ordering decreases the magnetostriction, the maximum magnetostriction should be largest for the (more disordered) binary Fe–Ga alloys as observed. Notably, addition of small amounts of C (0.07, 0.08, and 0.14 at. %) increases the magnetostriction of the slow cooled binary alloy to values comparable to the rapidly quenched alloy. We assume that small atom (C, B, N) additions enter interstitially and inhibit ordering, thus maximizing the magnetostriction without quenching

Magnetic field dependence of galfenol elastic properties

Elastic shear moduli measurements on Fe100−xGax (x = 12–33) single crystals (via resonant ultrasound spectroscopy) with and without a magnetic field and within 4–300 K are reported. The pronounced softening of the tetragonal shear modulus c′ is concluded to be, based on magnetoelastic coupling, the cause of the second peak in the tetragonal magnetostriction constant λ100 near x = 28. Exceedingly high ΔE effects ( ∼ 25%), combined with the extreme softness in c′ (c′\u3c10 GPa), suggest structural changes take place, yet, gradual in nature, as the moduli show a smooth dependence on Ga concentration, temperature, and magnetic field. Shear anisotropy (c44/c′) as high as 14.7 was observed for Fe71.2Ga28.8