Nanohybrid Materials with Tunable Birefringence via Cation Exchange in Polymer Films

In this work, a nanohybrid material based on a freestanding polymeric liquid crystal network capable of postmodification via cation exchange to tune birefringence is proposed. The smectic liquid crystal films can be infiltrated with a variety of cations, thereby changing the refractive indices (ne and no) and the effective birefringence (Δn) of the nanohybrid material, with reversible cation infiltration occurring within minutes. Birefringence could be tuned between values of 0.06 and 0.19, depending on the cation infiltrated into the network. Upon infiltration, a decrease in the smectic layer spacing is found with layer contraction independent of the induced change in birefringence. Potential applications are in the field of specialty optical devices, such as flexible, retunable reflective filters

Maternal ability to take care of children exposed to HIV

OBJECTIVE: to assess the ability of mothers to take care of children exposed to HIV, using the Assessment Scale of Care Skills for Children Exposed to HIV at Birth and to check the association between the scale dimensions and maternal characteristics. METHOD: this cross-sectional study involved 62 HIV+ mothers whose children of up to one year old had been exposed to the virus at birth. The Assessment Scale of Care Skills for Children Exposed to HIV at Birth consists of 52 items and five dimensions, indicating high, moderate or low care ability. RESULTS: 72.7% of the mothers appropriately offered zidovudine syrup; 86.0% were highly skilled to prepare and administer milk formula; 44.4% were moderately able to prepare and administer complementary feeding; 76.5% revealed high ability to administer prophylactic treatment against pneumonia and 95.3% demonstrated high abilities for clinical monitoring and immunization. Significant associations were found between some maternal variables and the scale dimensions. CONCLUSION: the scale permits the assessment of maternal care delivery to these children and the accomplishment of specific child health interventions

Can type of school be used as an alternative indicator of socioeconomic status in dental caries studies? A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Despite the importance of collecting individual data of socioeconomic status (SES) in epidemiological oral health surveys with children, this procedure relies on the parents as respondents. Therefore, type of school (public or private schools) could be used as an alternative indicator of SES, instead of collecting data individually. The aim of this study was to evaluate the use of the variable type of school as an indicator of socioeconomic status as a substitute of individual data in an epidemiological survey about dental caries in Brazilian preschool children.</p> <p>Methods</p> <p>This study followed a cross-sectional design, with a random sample of 411 preschool children aged 1 to 5 years, representative of Catalão, Brazil. A calibrated examiner evaluated the prevalence of dental caries and parents or guardians provided information about several individual socioeconomic indicators by means of a semi-structured questionnaire. A multilevel approach was used to investigate the association among individual socioeconomic variables, as well as the type of school, and the outcome.</p> <p>Results</p> <p>When all significant variables in the univariate analysis were used in the multiple model, only mother's schooling and household income (individual socioeconomic variables) presented significant associations with presence of dental caries, and the type of school was not significantly associated. However, when the type of school was used alone, children of public school presented significantly higher prevalence of dental caries than those enrolled in private schools.</p> <p>Conclusions</p> <p>The type of school used as an alternative indicator for socioeconomic status is a feasible predictor for caries experience in epidemiological dental caries studies involving preschool children in Brazilian context.</p

Dynamical Boson Stars

The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.Comment: 79 pages, 25 figures, invited review for Living Reviews in Relativity; major revision in 201

AIDS and jail: social representations of women in freedom deprivation situations

Abstract OBJECTIVE To graspthe AIDS social representations built by freedom-deprived women. METHOD Descriptive study with a quali-quantitative approach that involved 174 convicted women in a women's prison in a capital city of the Brazilian northeastern region. Aword-association test was applied in October and November 2014, using AIDS as a stimulus. The corpuswas processed usingIramuteq software. Descending Hierarchical Classification and Correspondence Factor Analysis were applied. RESULTS The content that comprises the social representation of AIDS was influenced by the prison context, which was pervaded by a lack of assistance, lack of knowledge, discrimination, and suffering that disclosed vulnerability to HIV/AIDS factors such as unprotected sex and object sharing. This underlines the stigma and fear of the illness, in addition to favoring and supporting negative feelings and a sense of rejection. CONCLUSION To consider the use of this representational amalgam to ensure a comprehensive, contextualized care can help redirect practices, motivate self-care practices, and reduce prejudiced attitudes

Hundreds of genetic barcodes of the species-rich hydroid superfamily Plumularioidea (Cnidaria, Medusozoa) provide a guide toward more reliable taxonomy

Marine hydroids are important benthic components of shallow and deep waters worldwide, but their taxonomy is controversial because diagnostic morphological characters to categorize taxa are limited. Their genetic relationships are also little investigated. We tested taxonomic hypotheses within the highly speciose superfamily Plumularioidea by integrating a classical morphological approach with DNA barcoding of the 16S and COI mitochondrial markers for 659 and 196 specimens of Plumularioidea, respectively. Adding Genbank sequences, we inferred systematic relationships among 1,114 plumularioids, corresponding to 123 nominal species and 17 novel morphospecies in five families of Plumularioidea. We found considerable inconsistencies in the systematics of nominal families, genera and species. The families Kirchenpaueriidae and Plumulariidae were polyphyletic and the Halopterididae paraphyletic. Most genera of Plumularioidea are not monophyletic. Species diversity is considerably underestimated. Within our study, at least 10% of the morphologically-distinctive morphospecies are undescribed, and about 40% of the overall species richness is represented by cryptic species. Convergent evolution and morphological plasticity therefore blur systematic relationships. Additionally, cryptic taxa occur frequently in sympatry or parapatry, complicating correspondence with type material of described species. Sometimes conspecificity of different morphotypes was found. The taxonomy of hydroids requires continued comprehensive revision.This work relied on several hydrozoan samples collected from various sites, with the aid of many people. Supplementary Table S1 refers many of the people involved in the collection and/or preservation of the samples. C.J.M. acknowledges his great buddy-divers Jaime N.-Ruiz (CIMAR, Univ. Costa Rica), Axel Calderon, Nathaniel Chu, Eleni Petrou (STRI, Smiths. Inst.), Hanae Spathias, Karen Koltes (at the Belize station, Smith. Inst.), Freya Sommer (Hopkins Marine Station), Remilson Ferreira ('Costa Norte', Sao Tome), Frederico Cardigos (DOP, Univ. Azores) and others that assisted the dives. C.J.M. also acknowledges Rita Castillo (CIMAR, Univ. Costa Rica), Plinio Gondola, Ligia Calderon, Laura Geyer, Maria Castillo (STRI, Smiths. Inst.), Gregory Ruiz (SERC, Smiths. Inst.), Paul Greenhall, William Keel (MSC, Smith. Inst.), Manuel Enes, Valentina Matos (IMAR/DOP, Univ. Azores), Filipe Porteiro, Joao Goncalves (OKEANOS/IMAR, Univ. Azores), Marina Cunha, Ascensao Ravara (CESAM, Univ. Aveiro), Shirley Pomponi (Harbor Branch, Florida Atlantic Univ.), Estrela Matilde (Fundacao Principe Trust), Monica Albuquerque, Ines Tojeira (EMEPC), Diana Carvalho (Nat. Mus. Nat. Hist., Lisbon) and many others colleagues that facilitated the morphologic classifications and deposition of the samples. Peter Schuchert (Mus. d'Hist. Nat. Geneve) kindly provided some DNA extractes. Todd Kincaid and his team of GUE divers (Project Baseline - Azores) collected valuable samples from unusual depths. Joana Boavida (CIIMAR, Univ. Algarve) facilitated some samples of the 'DeepReefs' project. Jim Drewery (Marine Scotland Science Inst.) also provided few samples. Dale Calder (Royal Ontario Museum) provided some bibliography to C.J.M. and discussed/resolved some dubios taxonomic classifications. Colleagues at the L.A.B. (NMNH, Smith. Inst.) were very supportive. The APC fees for open access publication were supported by a program of the Regional Government of the Azores ("Apoio ao funcionamento e gestao dos centros de I&D regionais: 2018 - DRCT-medida 1

Age, period, and cohort analysis of regular dental care behavior and edentulism: A marginal approach

<p>Abstract</p> <p>Background</p> <p>To analyze the regular dental care behavior and prevalence of edentulism in adult Danes, reported in sequential cross-sectional oral health surveys by the application of a marginal approach to consider the possible clustering effect of birth cohorts.</p> <p>Methods</p> <p>Data from four sequential cross-sectional surveys of non-institutionalized Danes conducted from 1975-2005 comprising 4330 respondents aged 15+ years in 9 birth cohorts were analyzed. The key study variables were seeking dental care on an annual basis (ADC) and edentulism. For the analysis of ADC, survey year, age, gender, socio-economic status (SES) group, denture-wearing, and school dental care (SDC) during childhood were considered. For the analysis of edentulism, only respondents aged 35+ years were included. Survey year, age, gender, SES group, ADC, and SDC during childhood were considered as the independent factors. To take into account the clustering effect of birth cohorts, marginal logistic regressions with an independent correlation structure in generalized estimating equations (GEE) were carried out, with PROC GENMOD in SAS software.</p> <p>Results</p> <p>The overall proportion of people seeking ADC increased from 58.8% in 1975 to 86.7% in 2005, while for respondents aged 35 years or older, the overall prevalence of edentulism (35+ years) decreased from 36.4% in 1975 to 5.0% in 2005. Females, respondents in the higher SES group, in more recent survey years, with no denture, and receiving SDC in all grades during childhood were associated with higher probability of seeking ADC regularly (<it>P </it>< 0.05). The interaction of SDC and age (<it>P </it>< 0.0001) was significant. The probabilities of seeking ADC were even higher among subjects with SDC in all grades and aged 45 years or older. Females, older age group, respondents in earlier survey years, not seeking ADC, lower SES group, and not receiving SDC in all grades were associated with higher probability of being edentulous (<it>P </it>< 0.05).</p> <p>Conclusions</p> <p>With the use of GEE, the potential clustering effect of birth cohorts in sequential cross-sectional oral health survey data could be appropriately considered. The success of Danish dental health policy was demonstrated by a continued increase of regular dental visiting habits and tooth retention in adults because school dental care was provided to Danes in their childhood.</p

Serologically defined variations in malaria endemicity in Pará state, Brazil

BACKGROUND: Measurement of malaria endemicity is typically based on vector or parasite measures. A complementary approach is the detection of parasite specific IgG antibodies. We determined the antibody levels and seroconversion rates to both P. vivax and P. falciparum merozoite antigens in individuals living in areas of varying P. vivax endemicity in Pará state, Brazilian Amazon region. METHODOLOGY/PRINCIPAL FINDINGS: The prevalence of antibodies to recombinant antigens from P. vivax and P. falciparum was determined in 1,330 individuals. Cross sectional surveys were conducted in the north of Brazil in Anajás, Belém, Goianésia do Pará, Jacareacanga, Itaituba, Trairão, all in the Pará state, and Sucuriju, a free-malaria site in the neighboring state Amapá. Seroprevalence to any P. vivax antigens (MSP1 or AMA-1) was 52.5%, whereas 24.7% of the individuals were seropositive to any P. falciparum antigens (MSP1 or AMA-1). For P. vivax antigens, the seroconversion rates (SCR) ranged from 0.005 (Sucuriju) to 0.201 (Goianésia do Pará), and are strongly correlated to the corresponding Annual Parasite Index (API). We detected two sites with distinct characteristics: Goianésia do Pará where seroprevalence curve does not change with age, and Sucuriju where seroprevalence curve is better described by a model with two SCRs compatible with a decrease in force of infection occurred 14 years ago (from 0.069 to 0.005). For P. falciparum antigens, current SCR estimates varied from 0.002 (Belém) to 0.018 (Goianésia do Pará). We also detected a putative decrease in disease transmission occurred ∼29 years ago in Anajás, Goianésia do Pará, Itaituba, Jacareacanga, and Trairão. CONCLUSIONS: We observed heterogeneity of serological indices across study sites with different endemicity levels and temporal changes in the force of infection in some of the sites. Our study provides further evidence that serology can be used to measure and monitor transmission of both major species of malaria parasite