Thermomechanical properties and thermal degradation kinetics of poly(methyl methacrylate) (PMMA) and polycarbonate (PC) filled with cerium-doped yttrium aluminium garnet (Ce:YAG) prepared by melt compounding

This paper reports on the thermomechanical properties and thermal degradation kinetics of poly(methyl methacrylate) (PMMA) and polycarbonate (PC) composites filled with cerium-doped yttrium aluminium garnet (Ce:YAG) at different contents ranging between 0.1 and 5 wt%, and prepared by melt compounding. The interaction between PMMA and the filler was much stronger than that between PC and the filler, and this resulted in a significant improvement in the dynamic mechanical properties of the PMMA composites. The presence of filler did not significantly increase the thermal stability of the PC, while an observable increase in the thermal stability was only observed at higher filler loadings for the PMMA composites. This was attributed to the stronger interaction between Ce:YAG and PMMA and/or its degradation volatiles

Morphology, interfacial interaction, and thermal degradation of polycarbonate/MCM-41 (nano)composites

This article reports on the morphology, interfacial interaction, thermal stability, and thermal degradation kinetics of polycarbonate (PC)/mesoporous silica (MCM-41) composites with various MCM-41 contents, prepared by melt compounding. The composites with low filler loadings (<0.3 wt%) maintained their transparency because of the well dispersed MCM-41 particles, but at higher filler loadings the composites lost their transparency due to the presence of agglomerates. The presence of agglomerates decreased the thermal stability of PC due to the reduced effectiveness of the particles to immobilize the polymer chains, free radicals, and volatile degradation products

Morphology, interfacial interaction, and thermal degradation of polycarbonate/MCM-41 (nano)composites

This article reports on the morphology, interfacial interaction, thermal stability, and thermal degradation kinetics of polycarbonate (PC)/mesoporous silica (MCM-41) composites with various MCM-41 contents, prepared by melt compounding. The composites with low filler loadings (<0.3\u2009wt%) maintained their transparency because of the well dispersed MCM-41 particles, but at higher filler loadings the composites lost their transparency due to the presence of agglomerates. The presence of agglomerates decreased the thermal stability of PC due to the reduced effectiveness of the particles to immobilize the polymer chains, free radicals, and volatile degradation products

Localized cyclical variations in immunoproteins in the female genital tract and the implications on the design and assessment of mucosal infection and therapies.

PROBLEM: Fluctuating hormones regulate reproductive processes in the female genital tract. Consequent changes in the local immunological environment are likely to affect cellular interaction with infectious agents and the assessment of therapies that target mucosal infections. METHOD OF STUDY: We compared Softcup and Weck-Cel sampling protocols and assessed the changes in the concentrations of 39 soluble proteins with menstrual cycle progression in the mucosal and peripheral compartments. RESULTS: We demonstrate that the mucosal immunological profile is distinct from serum with inflammatory and migratory signatures that are localized throughout the cycle. The analytes highlighted in the mucosal compartment were generally highest at the follicular phase with a tendency to fall as the cycle progressed through ovulation to the luteal phase. CONCLUSION: Our results underscore the need to consider these localized cyclical differences in studies aimed at assessing the outcome of disease and the efficacy of mucosal vaccines and other therapies

Influence of the Ce :YAG amount on structure and optical properties of Ce :YAG-PMMA composites for white LED

Ce:YAG-poly(methyl methacrylate) (PMMA) composites were prepared by using a melt compounding method, adding several amounts of Ce:YAG in the range 0.1–5wt.%. The optical properties of the obtained composites and of the composites combined with a blue LED were measured to investigate the effect of the amount of Ce:YAG on the resulting emitted light in view of possible application in white LED manufacture. An increase in Ce:YAG amount caused an increase in the emission and a shift of 15 nm, influencing the white LED performance. The structure and morphology of the composites were studied. The results show that the interaction between the two components, observed by using solid state NMR experiments, are the responsible for the observed shift.The authors acknowledge the University of Palermo, FFR 2012–2013 –ATE 0594 and CORI201

Recruitment of high risk women for HIV prevention trials: baseline HIV prevalence and sexual behavior in the CAPRISA 004 tenofovir gel trial

<p>Abstract</p> <p>Background</p> <p>Young women in sub-Saharan Africa bear a disproportionate burden of HIV infection compared to men but have limited options to reduce their HIV risk. Microbicides could fill an important HIV prevention gap for sexually active women who are unable to successfully negotiate mutual monogamy or condom use.</p> <p>Purpose</p> <p>This paper describes the baseline sample characteristics in the CAPRISA 004 trial which assessed the safety and effectiveness of the vaginal microbicide, 1% tenofovir gel for HIV prevention in South Africa.</p> <p>Methods</p> <p>This analysis assessed the baseline demographic, clinical and sexual behavior data of women screened and enrolled into the trial. The characteristics were summarized using descriptive summary measures; expressed as means and percent for categorical variables.</p> <p>Results</p> <p>HIV prevalence at screening was 25.8% [95% Confidence Interval (CI):23.9-27.7). Of the 889 eligibly enrolled women who contributed follow-up data, rural participants recruited from a family planning (FP) clinic were younger, more likely to be living apart from their regular partner, reported lower coital frequency, had lower condom use (p < 0.001). In contrast, urban participants recruited from a sexually transmitted disease (STD) clinic reported higher numbers of lifetime sexual partners, new partners in the last 30 days and receiving money in exchange for sex (p < 0.001).</p> <p>Conclusion</p> <p>The populations selected provide suitable diverse target groups for HIV prevention intervention studies.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00441298">NCT 00441298</a></p

South African buffalo-derived Theileria parva is distinct from other buffalo and cattle-derived T. parva

Theileria parva is a protozoan parasite transmitted by the brown-eared ticks, Rhipicephalus appendiculatus and Rhipicephalus zambeziensis. Buffaloes are the parasite’s ancestral host, with cattle being the most recent host. The parasite has two transmission modes namely, cattle–cattle and buffalo–cattle transmission. Cattle–cattle T. parva transmission causes East Coast fever (ECF) and January disease syndromes. Buffalo to cattle transmission causes Corridor disease. Knowledge on the genetic diversity of South African T. parva populations will assist in determining its origin, evolution and identify any cattle–cattle transmitted strains. To achieve this, genomic DNA of blood and in vitro culture material infected with South African isolates (8160, 8301, 8200, 9620, 9656, 9679, Johnston, KNP2, HL3, KNP102, 9574, and 9581) were extracted and paired-end whole genome sequencing using Illumina HiSeq 2500 was performed. East and southern African sample data (Chitongo Z2, Katete B2, Kiambu Z464/C12, Mandali Z22H10, Entebbe, Nyakizu, Katumba, Buffalo LAWR, and Buffalo Z5E5) was also added for comparative purposes. Data was analyzed using BWA and SAMtools variant calling with the T. parva Muguga genome sequence used as a reference. Buffalo-derived strains had higher genetic diversity, with twice the number of variants compared to cattle-derived strains, confirming that buffaloes are ancestral reservoir hosts of T. parva. Host specific SNPs, however, could not be identified among the selected 74 gene sequences. Phylogenetically, strains tended to cluster by host with South African buffalo-derived strains clustering with buffalo-derived strains. Among the buffalo-derived strains, South African strains were genetically divergent from other buffalo-derived strains indicating possible geographic sub-structuring. Geographic substructuring was also observed within South Africa strains. The knowledge generated from this study indicates that to date, ECF is not circulating in buffalo from South Africa. It also shows that T. parva has historically been present in buffalo from South Africa before the introduction of ECF and was not introduced into buffalo during the ECF epidemic.The Department of Agriculture, Land Reform and Rural Developmenthttp://www.frontiersin.org/Geneticsam2022Veterinary Tropical Disease

Intimate partner violence and infant morbidity: evidence of an association from a population-based study in eastern Uganda in 2003

<p>Abstract</p> <p>Background</p> <p>Although recent studies suggest that there is an association between intimate partner violence and child mortality, the underlying mechanisms are still unknown. It is against this background that as a secondary objective, we set out to explore whether an association exists between intimate partner violence and illness in infants.</p> <p>Methods</p> <p>We conducted a population based household survey in Mbale, eastern Uganda in 2003. Participants were 457 women (with 457 infants) who consented to participate in the study. We measured socio-demographics of women and occurrence of intimate partner violence. We measured socio-demographics, immunization, nutritional status, and illness in the previous two weeks of the children.</p> <p>Results</p> <p>The mean age of the women was 25 years (SD 5.7) while the mean age of the infants was 6 months (SD 3.5). The prevalence of lifetime intimate partner violence was 54% (95% CI 48%–60%). During the previous two weeks, 50% (95% CI 50%–54%) of the children had illness (fever, diarrhoea, cough and fast breathing). Lifetime intimate partner violence was associated with infant illness (OR 1.8, 95% CI 1.2–2.8) and diarrhoea (OR 2.0, 95% CI 1.2–3.4).</p> <p>Conclusion</p> <p>Our findings suggest that infant illnesses (fever, diarrhoea, cough and fast breathing) are associated with intimate partner violence, and provide insights into previous reports that have shown an association between intimate partner violence and child mortality, suggesting possible underlying mechanisms. Our findings also highlight the importance of intimate partner violence on the health of children, and the need for further research in this area.</p