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Background Global immune activation and HLA alleles are each associated with the pathogenesis of human immunodeficiency virus (HIV) and hepatitis C virus . Methods We evaluated the relationship between 44 HLA class I and 28 class II alleles and percentages of activated CD8 (CD8+CD38+DR+) and CD4 (CD4+CD38+DR+) T cells in 586 women who were naive to highly active antiretroviral therapy. We used linear generalized estimating equation regression models, adjusting for race/ethnicity, age, HIV load, and hepatitis C virus infection and controlling for multiplicity using a false discovery rate threshold of 0.10. Results Ten HLA alleles were associated with CD8 and/or CD4 T-cell activation. Lower percentages of activated CD8 and/or CD4 T cells were associated with protective alleles B*57:03 (CD8 T cells, −6.6% [P = .002]; CD4 T cells, −2.7% [P = .007]), C*18:01 (CD8 T cells, −6.6%; P < .0008) and DRB1*13:01 (CD4 T cells, −2.7%; P < .0004), and higher percentages were found with B*18:01 (CD8 T cells, 6.2%; P < .0003), a detrimental allele. Other alleles/allele groups associated with activation included C*12:03, group DQA1*01:00, DQB1*03:01, DQB1*03:02, DQB1*06:02, and DQB1*06:03. Conclusion These findings suggest that a person’s HLA type may play a role in modulating T-cell activation independent of viral load and sheds light on the relationship between HLA, T-cell activation, immune control, and HIV pathogenesis.

OBJECTIVES Hepatitis C virus (HCV) infection causes an alteration in T-cell maturation and activation in patients coinfected with human immunodeficiency virus (HIV). Because interleukin 7 (IL-7) is a major cytokine controlling T-cell homeostasis, we analyzed the potential influence of HCV coinfection on circulating IL-7 levels in HIV-infected women before and after highly active antiretroviral therapy (HAART). DESIGN AND METHODS This prospective study included 56 HIV monoinfected, 55 HIV/HCV coinfected without HCV viremia, 132 HIV/HCV coinfected with HCV viremia, and 61 HIV/HCV-uninfected women for whom plasma levels of IL-7 were determined by enzyme-linked immunosorbent assay at 1 or more follow-up visits before and after HAART. Cross-sectional analyses of the associations between plasma IL-7 levels and HCV infection, demographic, clinical, and immunologic characteristics were evaluated using univariate and multivariate linear regression models before and after HAART. RESULTS In multivariate models, IL-7 levels were significantly higher in coinfected HCV viremic women than in HIV monoinfected women (multiplicative effect = 1.48; 95% confidence interval: 1.01 to 2.16; P = 0.04) before HAART, but were similar between these two groups among women after HAART. In addition to HCV viremia, higher IL-7 levels were associated with older age (P = 0.02), lower CD4(+) T-cell count (P = 0.0007), and higher natural killer T-cell count (P = 0.02) in women before HAART. Among HAART-treated women, only lower CD4(+) T-cell count was significantly associated with IL-7 level (P = 0.006). CONCLUSIONS Our data demonstrate that in HIV-infected women, circulating levels of IL-7 are strongly associated with CD4 T-cell depletion both before and after HAART. Our data also demonstrate that HCV viremia increases circulating IL-7 levels before HAART but not after HAART in coinfected women. This suggests that the effect of HCV on lymphopenia is abrogated by HAART.

Context Autoimmune thyroid disease is more common in women than in men. Fetal microchimerism has been implicated as a potential explanation for this disparity. Objective The objective of this study was to evaluate the relationship between parity and thyroid autoimmunity in the US population. Design, Setting, Patients The National Health and Nutrition Examination Survey was used to identify females with antithyroperoxidase (TPOAb) and antithyroglobulin antibody (TgAb) measurements and parity data. Subjects (n = 4864) were categorized as never pregnant (n = 909) or previously pregnant (n = 3955). The association of parity with thyroid autoantibodies was examined both qualitatively and quantitatively. Thyroid autoimmunity was defined as TPOAb and/or TgAb titers above the reference limits. Results Previous pregnancy carried an odds ratio (OR) of 1.55 [95% confidence interval (CI): 1.26 to 1.91] for thyroid autoimmunity compared with never pregnant. Number of pregnancies was associated with thyroid autoimmunity: OR = 1.37 (95% CI: 1.02 to 1.84); 1.4 (95% CI: 1.08 to 1.81); 1.52 (95% CI: 1.18 to 1.96); and 1.73 (95% CI: 1.38 to 2.18) for 1, 2, 3, and ≥4 pregnancies, respectively. Because ever-pregnant women differed in several variables—age, race, smoking status, history of thyroid disease, and urinary iodine level—from never-pregnant women (P < 0.001), a multivariate regression analysis was performed, which showed no association of pregnancy with thyroid autoimmunity. The association was further examined utilizing an age-matched analysis, which confirmed the absence of an association between thyroid autoimmunity and parity. Conclusion Although we initially observed a strong association between parity and thyroid autoimmunity, after controlling for age and other variables, we were unable to identify an association.

Cervicovaginal HIV level (CV-VL) influences HIV transmission. Plasma viral load (PVL) correlates with CV-VL, but discordance is frequent. We evaluated how PVL, behavioral, immunological, and local factors/conditions individually and collectively correlate with CV-VL.CV-VL was measured in the cervicovaginal lavage fluid (CVL) of 481 HIV-infected women over 976 person-visits in a longitudinal cohort study. We correlated identified factors with CV-VL at individual person-visits and detectable/undetectable PVL strata by univariate and multivariate linear regression and with shedding pattern (never, intermittent, persistent ≥3 shedding visits) in 136 women with ≥3 visits by ordinal logistic regression.Of 959 person-visits, 450 (46.9%) with available PVL were discordant, 435 (45.3%) had detectable PVL with undetectable CV-VL, and 15 (1.6%) had undetectable PVL with detectable CV-VL. Lower CV-VL correlated with highly active antiretroviral therapy (HAART) usage (P = 0.01). Higher CV-VL correlated with higher PVL (P0.001), inflammation-associated cellular changes (P = 0.03), cervical ectopy (P = 0.009), exudate (P = 0.005), and trichomoniasis (P = 0.03). In multivariate analysis of the PVL-detectable stratum, increased CV-VL correlated with the same factors and friability (P = 0.05), while with undetectable PVL, decreased CV-VL correlated with HAART use (P = 0.04). In longitudinal analysis, never (40.4%) and intermittent (44.9%) shedding were most frequent. Higher frequency shedders were more likely to have higher initial PVL [odds ratio (OR) = 2.47/log10 increase], herpes simplex virus type 2 seropositivity (OR = 3.21), and alcohol use (OR = 2.20).Although PVL correlates strongly with CV-VL, discordance is frequent. When PVL is detectable, cervicovaginal inflammatory conditions correlate with increased shedding. However, genital shedding is sporadic and not reliably predicted by associated factors. HAART, by reducing PVL, is the most reliable means of reducing cervicovaginal shedding.

Over the past years, spin and magnetic-field effects in devices operate by means of an organic spin valve using organic conjugated materials. As the interfacial properties in a ferromagnet–organic hybrid structure critically affect the performance of organic spintronic devices, understanding the interplay between interfaces in these hybrid structures becomes important. To study the interfacial electronic and magnetic properties of Co/Pentacene(Pc)/Co/Cr/Si(1 0 0) in a vertical pseudo-spin-valve structure, we employed synchrotron photoelectron spectra (PES), near-edge X-ray absorption fine structure (NEXAFS) and the magneto-optical Kerr effect (MOKE) to examine the interfacial hybrid state for Pc on Co (Co/Pc) and vice versa for Pc/Co bilayers. The evidences from PES, NEXAFS and MOKE suggest an asymmetric electronic and magnetic interface for Co/Pc and Pc/Co. The Co/Pc interface presents a chemically stable surface, but Pc/Co displays a reacted interface with a magnetically dead layer on the surface. Assisted with a calculation based on the density-functional theory, we elucidate the possible origin of the electronic and magnetic degradation for Co atop Pc in the interfacial regime.

We investigated two series of ultrathin ferromagnet-organic semiconductor (FM-OSC) hybrid structures fabricated with reversed layer orders in ultra-high vacuum conditions to emulate the interfaces of FM/OSC/FM organic spin-valves. Using X-ray photoemission electron microscopy (PEEM), the magnetic responses of the cobalt (Co) layer in contact with the pentacene (Pc) film were investigated on a microscopic scale. According to the PEEM images acquired on Pc (1.8 nm)/Co bilayers, the Co top layer was found to turn on its ferromagnetic order after its thickness reaches 2.2 nm. Also, upon the onset of magnetic contrast, the element-specific images revealed that the Pc/Co bilayers exhibit a complex domain pattern whose average dimension is at least two orders of magnitude smaller than that of the pattern found in Co (2.4 nm)/Pc bilayers. Further X-ray photoelectron spectroscopy investigations suggest that the magnetic disparities observed between Co/Pc and Pc/Co bilayers are correlated with the different chemistries occurred at their interfaces.

The effects of different grafting content of 4,4′-methlenebis(phenyl isocyanate)-modified attapulgite (ATT-MDI) on thermal and mechanical properties of segmented polyurethane (PU) elastomers were investigated. The ATT-MDI nanorods with different grafting content were prepared by treating ATT with heat and acid followed by grafting with MDI molecules. MDI-modified ATT were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy. TGA analysis revealed that at least 30 wt % of MDI was grafted/adsorbed on the surface of ATT following the modification. Three PU/ATT-MDI nanocomposites were in situ synthesized using ATT with different grafting contents, and the materials were characterized by TEM, thermal analysis, and mechanical testing. The tensile strength and modulus increased with increasing grafting content of MDI molecules, and the crystallinity of soft and hard segments was increased by ATT-MDI. POLYM. COMPOS., 31:1890–1898, 2010. © 2010 Society of Plastics Engineers.

The effects of soft-segment molecular weight and organic modification of montmorillonite (MMT) on thermal and mechanical properties of segmented polyurethane (PU) elastomers were investigated. The PU/MMT nanocomposites were prepared by in situ polymerization, and the compositions included soft segments with number average molecular weights of 1000, 2000, and 2900, and organic-modified MMT (including MMT-30B and MMT-I30E). The nanocomposites produced were characterized using wide-angle X-ray diffraction (WAXD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and mechanical testing. The TEM and XRD results revealed that both MMT-30B and MMT-I30E were intercalated, and partially exfoliated by the PU. Mechanical tests showed that the PU1000 series in soft-segment molecular weight yielded superior tensile properties compared with the PU2000 and PU2900 series. Also, for a given molecular weight of soft segment in PU, the MMT-30B nanocomposites exhibited greater increases in Young's modulus, tensile strength, and elongation at break than the MMT-I30E counterpart, and the crystallinity of PU was enhanced by the clays. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Background There is a paucity of controlled clinical data on the best initial therapy for treating patients with bipolar type II (BP II) major depressive episode (MDE). In this analysis, we examined the safety and antidepressant efficacy of short-term venlafaxine versus lithium monotherapy in rapid and non-rapid cycling patients with BP II MDE. We hypothesized that lithium would have superior efficacy to venlafaxine, with fewer syndromal and sub-syndromal hypomanic and mixed mood conversions in the rapid cycling BP II MDE patients. Methods Patients were randomized to monotherapy with either venlafaxine 37.5–375 mg daily or lithium 300–2100 mg daily for 12 weeks. The primary outcome measure was the 28-item Hamilton Depression Rating (HAM-D 28), with embedded ‘typical’ HAM-D 17 and ‘atypical’ HAM-D 17-R symptom scores. Secondary outcomes included the Young Mania Rating Scale (YMRS), clinical global impressions severity (CGI/S) and change (CGI/C) ratings, the proportion of responders (with ≥ 50% reduction in baseline HAM-D score) and remitters (with a final HAM-D score ≤ 8), and the proportion of patients with syndromal and sub-syndromal mood conversions. Results Forty-three patients received venlafaxine (12 rapid cycling) and 40 patients received lithium (15 rapid cycling): 48 (57.8%) were women and 69 (82.1%) were Caucasian. Thirty-three patients (39.8%) prematurely discontinued therapy: 11 for lack of efficacy, 13 for adverse events, 2 for non-compliance, and 7 who were lost to follow up. Venlafaxine produced a greater reduction in HAM-D 28 (p = 0.001) and HAM-D 17 (p = 0.002) scores (versus lithium) that was independent of cycling status (0.358). Venlafaxine also resulted in a higher rate of responders (p = 0.021) and remitters (p = 0.001) in rapid cycling patients. There was no significant difference in baseline mean YMRS scores, or mean YMRS change scores over time, between rapid and non-rapid cycling patients. Venlafaxine did not result in a higher proportion of mood conversions (versus lithium) in either the rapid or non-rapid cycling patients. Limitations This was a secondary analysis of rapid versus non-rapid cycling BP II MDE patients. The study was originally powered to detect differences in efficacy between treatment conditions, and was not specifically powered to detect differences in efficacy or mood conversion episodes between rapid and non-rapid cycling groups. We used a conservative life-time definition of rapid cycling (i.e., an average ≥ 4 affective episodes per year). We did not employ a patient-recorded daily chrono-record to identify ultra-short mood conversions. The study used a randomized, parallel group, open-label design. Conclusion These observations from this exploratory analysis suggest that venlafaxine monotherapy may be more effective than lithium monotherapy, with a similar mood conversion rate, in rapid and non-rapid cycling patients with BP II MDE. These data support prior observations that venlafaxine monotherapy may be effective initial treatment for BP II MDE.

This paper proposes a model of power-quality detection for power system disturbances using adaptive wavelet networks (AWNs). An AWN is a two-subnetwork architecture, consisting of the wavelet layer and adaptive probabilistic network. Morlet wavelets are used to extract the features from various disturbances, and an adaptive probabilistic network analyzes the meaningful features and performs discrimination tasks. AWN models are suitable for application in a dynamic environment, with add-in and delete-off features using automatic target adjustment and parameter tuning. The proposed AWN has been tested for the power-quality problems, including those caused by harmonics, voltage sag, voltage swell, and voltage interruption. Compared with conventional wavelet networks, the test results showed accurate discrimination, fast learning, good robustness, and faster processing time for detecting disturbing events.

To evaluate the effect of powerless contact lens on improving the quality of optical coherence tomography imaging of rodent retina.A spectral-domain optical coherence tomography (SD-OCT) system was built for in vivo imaging of rodent retina. The calibrated depth resolution of the system was 3 µm in tissue. A commercial powerless contact lens for rat eye was tested in the experiments. For each rat eye, the retina was imaged in vivo sequentially first without wearing contact lens and then with wearing contact lens. The lateral resolution and signal-to-noise ratio of the OCT images with and without contact lens were compared to evaluate the improvement of image quality.The fundus images generated from the measured 3D OCT datasets with contact lens showed sharper retinal blood vessels than those without contact lens. The contrast of the retinal blood vessels was also significantly enhanced in the OCT fundus images with contact lens. As high as 10 dB improvements in SNR was observed for OCT images with contact lens compared to the images of the same retinal area without contact lens.We have demonstrated that the use of powerless contact lens on rat eye can significantly improve OCT image quality of rodent retina, which is a benefit in addition to preventing cataract formation. We believe the improvement in image quality is the result of partial compensation of the optical aberrations of the rodent eye by the contact lens.

To emulate the interfacial regimes of a $\mathrm{Co}/\mathrm{Pc}/\mathrm{Co}$ spin-valve structure, we fabricated ultrathin pentacene/cobalt ($\mathrm{Pc}/\mathrm{Co}$) and cobalt/pentacene ($\mathrm{Co}/\mathrm{Pc}$) bilayers. Through measurement of the magneto-optical Kerr effect, we found the Co layer has its magnetic properties depend strongly upon the order of deposition. Further x-ray spectroscopy and microscopy investigation indicated $\mathrm{Co}/\mathrm{Pc}$ was chemically stable, whereas $\mathrm{Pc}/\mathrm{Co}$ was reactive and exhibited complex magnetization pattern. The different chemistry and magnetic configurations at interfaces could cause additional complication for spin injection.

Composite syntactic foams with different densities were fabricated with hollow phenolic microspheres, a phenolic resin binder, and a small addition of chopped carbon fibers. Compressive, shear, and tensile properties were studied for the syntactic foams with and without carbon fibers. Two fiber layer orientations, either parallel (P-type) or perpendicular (N-type) to the loading direction, were considered in the mechanical testing. For N-type foams, mechanical properties were weakly dependent on foam density. For P-type foams, the mechanical properties of the foams were strongly dependent on the strength of the supporting matrix. The specific strength and specific stiffness of the P-type foams were significantly enhanced compared with the neat foams. These findings indicate that fiber reinforcement is an effective way to enhance the mechanical performance of syntactic foams, and the enhanced performance should lead to applications as a foam core material for sandwich structures. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers

The interfacial regimes of cobalt/pentacene/cobalt (Co/Pc/Co) trilayers were emulated through the ultrathin pentacene/cobalt (Pc/Co) and cobalt/pentacene (Co/Pc) bilayers. Employing the magneto-optical Kerr effect (MOKE) measurement, we found the coercivity of Co bottom film in a thickness of 3.4 nm experienced a slight reduction upon the adsorption of Pc molecules. For the bilayers prepared with reversed order of deposition, the Co film deposited on a 6.4 nm Pc layer showed no observable ferromagnetic order at room temperature until its thickness reached 3 nm. After the onset of magnetic order, the x-ray images acquired on Pc/Co revealed a complicated magnetization patterns comparing to those observed on Co/Pc bilayers. Because the spin-polarized carriers will interact with the environment along their transport path, the presence of a non-magnetic layer and the occurrence of complicated domain structures suggested the spin-polarized carriers would experience a greater disturbance on their spin coherence when crossing the Pc/Co interface.

Polyurethane (PU) nanocomposites filled with attapulgite (ATT) nanorods were synthesized and characterized with thermal analysis, dynamic mechanical analysis (DMA), and mechanical testing. The formulations were based on 4,4′-methylene bis(phenyl isocyanate) (MDI), polytetrahydrofuran, 1,4-butanediol, and inorganic ATT premodified with MDI. The original and premodified ATT (ATT-OH and ATT-MDI) nanorods were characterized with thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The analysis revealed that 17 wt % MDI was grafted/adsorbed onto the surface of ATT as a result of the modification. Pristine PU and ATT-MDI/PU nanocomposites were characterized with scanning electron microscopy, differential scanning calorimetry, and TGA. The mechanical tests and DMA showed an increase in the storage modulus and Young's modulus with increasing ATT-MDI content. The crystallinity of the hard and soft segments and thermal stability showed enhancements over those of the neat resin. Fil: Wang, Chia-Hao. University Of Southern California; Estados Unidos Fil: Auad, Maria L.. Auburn University; Estados Unidos Fil: Marcovich, Norma Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Nutt, Steven. University Of Southern California; Estados Unidos

While Web service models become increasingly popular and many service providers start to offer all kinds of Web services, the quality of service (QoS) for Web services has become an important factor for service requesters to consider during the selection process of appropriate Web services. In this paper, we present an evaluation and selection framework (CosmosQoS) for QoS-required Web services. A novel architecture and reputation appraisal model to monitor, store and evaluate the physical usage and post-condition of requested Web services in a requester-located network is proposed to better support service requesters such that they can select suitable Web services based on their QoS requirements, trustworthiness of Web services, and effect of network connection and configuration between service requesters and providers.

This paper presents numerical examples that shows the results predicted by the RBF-NN models are consistent with those calculated from existing studies. It should be noted that the RBF-NN model is inherently one type of the general regression. This makes it powerful in modeling and predicting such a nonlinear problem. With the use of neural networks, the complex numerical computation about arrays of nonlinear antennas can be replaced by a very simple algebraic operation as the neural networks are well trained. Although the training work of a RBF-NN model is usually time consuming, it can be completed in advance. This study is useful in the applications of antenna design, remote sensing and wireless communication.

Using x-ray spectromicroscopy, we studied the interface of pentacene (Pn)-cobalt (Co) heterojunction fabricated by thermal evaporation in an ultra-high vacuum environment. Through element-specific images and absorption spectroscopic analysis, we found evidences suggesting that part of the Co top layer penetrates into Pn film and hybridizes with molecules. As the Curie temperature of infiltrated Co clusters is dimension sensitive, the Co penetration would create an ill-defined interfacial region whose magnetization depends on the temperature and depth of cobalt penetration. The magnetic complexity at Pn/Co interface was found reduced after inserting a thin Cu layer between Pn and Co.