Heterogeneity of helper/inducer T lymphocytes. II. Effects of interleukin 4- and interleukin 2-producing T cell clones on resting B lymphocytes.

To compare the helper function of murine T cell clones that secrete IL-2 and IFN-gamma (Th1 cells) or IL-4 and IL-5 (Th2), purified resting B cells were stimulated with F(ab')2 rabbit anti-mouse Ig (RAMG) and rabbit Ig-specific, class II MHC-restricted cloned T cells belonging to the two subsets. Both Th2 clones examined induced strong proliferative responses of B cells in the presence of RAMG, as well as the secretion of IgM and IgG1 antibodies. In contrast, the Th1 clones tested failed to stimulate B cell growth or antibody secretion. Th2-mediated B cell activation was dependent on IL-4 and IL-5, and was also inhibited by IFN-gamma or IFN-gamma produced by Th1 cells present in the same cultures. However, the failure of Th1 cells to help resting B cells could not be reversed with neutralizing anti-IFN-gamma antibody. In addition to this inhibitory effect, IFN-gamma was required for the secretion of IgG2a antibody, particularly when B cells were stimulated with polyclonal activators such as LPS. Finally, both sets of T cell clones secreted lymphokines when stimulated with purified B cells and RAMG. These experiments demonstrate that T cells that differ in lymphokine production also differ in their ability to help B cells as a result of cognate interactions at low concentrations of antigens. Moreover, IL-4, IL-5, and IFN-gamma serve different roles in the T cell-dependent proliferative and differentiative responses of resting B lymphocytes

The Bradford & Airedale Health of Men initiative: a study of its effectiveness in engaging with men

The Health of Men (HoM) network received funding from the Big Lottery Fund in 2003 to establish a five year programme of dedicated work with men and boys. This enabled a team of practitioners to be creative and to build upon their existing skills to generate models of working with those men in the community that are usually seen as hard to reach. The research which has accompanied of the work of team has explored why men use these new services and has demonstrated the following: • Men do care about their health • Men are willing and able to engage with their health when services are tailored to their needs • Men from different culture groups and socio-economic backgrounds who are normally seen as hard to reach were accessed. • A model encompassing a dedicated team working with men is worthy of further development Much has been learnt from this project that has great relevance to the local Primary Care Trust (PCT), but has also proved a great source of information for the development of services to men on a Regional, National and International level

Boundedness of Pseudodifferential Operators on Banach Function Spaces

We show that if the Hardy-Littlewood maximal operator is bounded on a separable Banach function space $X(\mathbb{R}^n)$ and on its associate space $X'(\mathbb{R}^n)$, then a pseudodifferential operator $\operatorname{Op}(a)$ is bounded on $X(\mathbb{R}^n)$ whenever the symbol $a$ belongs to the H\"ormander class $S_{\rho,\delta}^{n(\rho-1)}$ with $0<\rho\le 1$, $0\le\delta<1$ or to the the Miyachi class $S_{\rho,\delta}^{n(\rho-1)}(\varkappa,n)$ with $0\le\delta\le\rho\le 1$, $0\le\delta0$. This result is applied to the case of variable Lebesgue spaces $L^{p(\cdot)}(\mathbb{R}^n)$.Comment: To appear in a special volume of Operator Theory: Advances and Applications dedicated to Ant\'onio Ferreira dos Santo

A vine copula mixed effect model for trivariate meta-analysis of diagnostic test accuracy studies accounting for disease prevalence

A bivariate copula mixed model has been recently proposed to synthesize diagnostic test accuracy studies and it has been shown that it is superior to the standard generalized linear mixed model in this context. Here, we call trivariate vine copulas to extend the bivariate meta-analysis of diagnostic test accuracy studies by accounting for disease prevalence. Our vine copula mixed model includes the trivariate generalized linear mixed model as a special case and can also operate on the original scale of sensitivity, specificity, and disease prevalence. Our general methodology is illustrated by re-analyzing the data of two published meta-analyses. Our study suggests that there can be an improvement on trivariate generalized linear mixed model in fit to data and makes the argument for moving to vine copula random effects models especially because of their richness, including reflection asymmetric tail dependence, and computational feasibility despite their three dimensionality

STUDY OF THERMAL INTERACTION OF CELL-PHONE RADIATIONS WITHIN HUMAN HEAD TISSUES

In the present investigation, a theoretical model based on Maxwell equations, microscopic form of ohm's law and Joules law of heating effect is proposed for the study of penetration depth, attenuation coefficient and specific absorption rate (SAR) with varying distance between the source of radiation and exposed human head tissues (skin, fat, brain and bone). In addition, corresponding temperature increase inside these various human head tissues is also calculated. Results of present study indicate that the temperature rise in human tissue depends upon specific absorption rate and the duration for which human body is actually exposed to GSM radiations.  By assuming the distance of 1cm and exposure time of 5 minutes, the highest SAR was estimated to be 1681.7 W/Kg for the brain tissue at 900 MHz and 4038.5 W/Kg for 1800 MHz. Maximum skin depth and attenuation coefficient was found to be in the case of fat and brain tissue, respectively amongst rest head tissues. The corresponding highest temperature rise for the brain tissue was calculated to be 2.31K at 900 MHz and 5.54K at 1800 MHz frequencies

C IV BAL disappearance in a large SDSS QSO sample

Broad absorption lines (BALs) in the spectra of quasi-stellar objects (QSOs) originate from outflowing winds along our line of sight; winds are thought to originate from the inner regions of the QSO accretion disk, close to the central supermassive black hole (SMBH). Winds likely play a role in galaxy evolution and aid the accretion mechanism onto the SMBH. BAL equivalent widths can change on typical timescales from months to years; such variability is generally attributed to changes in the covering factor and/or in the ionization level of the gas. We investigate BAL variability, focusing on BAL disappearance. We analyze multi-epoch spectra of more than 1500 QSOs -the largest sample ever used for such a study- observed by different programs from the Sloan Digital Sky Survey-I/II/III (SDSS), and search for disappearing C IV BALs. The spectra rest-frame time baseline ranges from 0.28 to 4.9 yr; the source redshifts range from 1.68 to 4.27. We detect 73 disappearing BALs in the spectra of 67 sources. This corresponds to 3.9% of disappearing BALs, and 5.1% of our BAL QSOs exhibit at least one disappearing BAL. We estimate the average lifetime of a BAL along our line of sight (~ 80-100 yr), which appears consistent with the accretion disk orbital time at distances where winds are thought to originate. We inspect properties of the disappearing BALs and compare them to the properties of our main sample. We also investigate the existence of a correlation in the variability of multiple troughs in the same spectrum, and find it persistent at large velocity offsets between BAL pairs, suggesting that a mechanism extending on a global scale is necessary to explain the phenomenon. We select a more reliable sample of disappearing BALs following Filiz Ak et al. (2012), where a subset of our sample was analyzed, and compare the findings from the two works, obtaining generally consistent results.Comment: 22 pages, 9 figures. Accepted for publication in A&

Hybrid copula mixed models for combining case-control and cohort studies in meta-analysis of diagnostic tests

Copula mixed models for trivariate (or bivariate) meta-analysis of diagnostic test accuracy studies accounting (or not) for disease prevalence have been proposed in the biostatistics literature to synthesize information. However, many systematic reviews often include case-control and cohort studies, so one can either focus on the bivariate meta-analysis of the case-control studies or the trivariate meta-analysis of the cohort studies, as only the latter contains information on disease prevalence. In order to remedy this situation of wasting data we propose a hybrid copula mixed model via a combination of the bivariate and trivariate copula mixed model for the data from the case-control studies and cohort studies, respectively. Hence, this hybrid model can account for study design and also due to its generality can deal with dependence in the joint tails. We apply the proposed hybrid copula mixed model to a review of the performance of contemporary diagnostic imaging modalities for detecting metastases in patients with melanoma

Eclipsing Binaries Showing Light Time Effect

Four eclipsing binaries, which show apparent changes of period, have been studied with respect to a possible presence of the light time effect. With a least squares method we calculated new light elements of these systems, the mass function of the predicted third body, and its minimum mass. We discuss the probability of the presence of such bodies in terms of mass function, changes in radial velocity and third light in solution of light curves.Comment: 4 pages, 4 figures, 1 table, conference proceeding