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There is no agreement regarding which solvent is more suitable to obtain sol–gel–derived titania (TiO2) samples with an enhanced photocatalytic behavior. Furthermore, the solvent effect on the preparation of TiO2-RGO (reduced graphene oxide) nanocomposites has not been published yet and could be an attractive experimental strategy to modulate structure and properties. On the basis of these observations, TiO2-RGO nanocomposites were fabricated in this study. It was evaluated for the influence of using either isopropyl (IsoprOH) or ethyl (EtOH) alcohol on the textural and photocatalytic properties of the prepared materials. The use of IsoprOH led to samples with smaller crystallite size, narrower apparent band gap, smaller isoelectric point, larger adsorption capacity, and higher photocatalytic activity. In addition, the incorporation of RGO into TiO2 greatly improved the adsorption capacity and photocatalytic activity of the latter. However, the optimal loading of RGO to prepare composites with enhanced photocatalytic activities was 1 wt%. This finding can be related to the stacking of RGO sheets when concentrations above 1 wt% are used, which could prevent UV light to reach the TiO2 particles and also decrease the photocatalytic capacity of the composites. Moreover, materials with RGO concentration above 1 wt% could exhibit a highly negatively charged surface, which may decrease the separation of the generated electron–hole pairs and lead to faster recombination rates of charge carriers.
The semiconductor industry is continually striving'for smaller, denser devices. Microdiffractometry is an analytical technique which endeavors to apply x-ray diffraction techniques for measuring strain and phase information to areas approaching 50 micrometers diameter or less.
This study extends the work of Goldsmith and Walker in the measurement of strain using the lattice distortion or sin2(ψ) plot method.
The systematic errors arising from both sample and beam displacement relative to the center of rotation of the cample ie examined. A relationship is derived which predicts the influence of these displacements upon the slope of a stress plot. The predictions are compared to experiment.
The influence of random errors arising from particle size and photon counting statistics will also be discussed. Guidelines will be presented which will minimize both systematic and random errors.
The goal of this study was to analyse the spatial pattern of tuberculosis (TB) mortality using different approaches, namely: mortality rates (MR), spatial relative risks (RR) and Bayesian rates (Global and Local) and their association with human development index (HDI), Global and its three dimensions: education, longevity and income. An ecological study was developed in Curitiba, Brazil based on data from Mortality Information System (2008–2014). Spatial scan statistics were used to compute RR and identify high-risk clusters. Bivariate Local Indicator of Spatial Associations was used to assess associations. MR ranged between 0 and 25.24/100.000 with a mean (standard deviation) of 1.07 (2.66). Corresponding values for spatial RR were 0–27.46, 1.2 (2.99) and for Bayesian rates (Global and Local) were 0.49–1.66, 0.90 (0.19) and 0–6.59, 0.98 (0.80). High-risk clusters were identified for all variables, except for HDI-income and Global Bayesian rate. Significant negative spatial relations were found between MR and income; between RR and HDI global, longevity and income; and Bayesian rates with all variables. Some areas presented different patterns: low social development/low risk and high risk/high development. These results demonstrate that social development variables should be considered, in mortality due TB.
Evidence suggests that skin picking disorder (SPD) could be a prevalent condition associated with comorbidity and psychosocial dysfunction. However, just a few studies have assessed the prevalence and correlates of SPD in samples from low- and middle-income countries. In addition, the impact of SPD on quality of life (QoL) dimension after multivariable adjustment to potential confounders remains unclear.
Data were obtained from a Brazilian anonymous Web-based research platform. Participants provided sociodemographic data and completed the modified Skin Picking–Stanford questionnaire, the Hypomania Checklist (HCL-32), the Patient Health Questionnaire-9 (PHQ-9), the Fagerström Test for Nicotine Dependence, Alcohol Use Disorder Identification Test (AUDIT), Symptom Checklist-90-Revised inventory (SCL-90R), early trauma inventory self report–short form, and the World Health Organization quality of life abbreviated scale (WHOQOL-Bref). Associations were adjusted to potential confounders through multivariable models.
For our survey, 7639 participants took part (71.3% females; age: 27.2±7.9 years). The prevalence of SPD was 3.4% (95% CI: 3.0–3.8%), with a female preponderance (P<0.001). In addition, SPD was associated with a positive screen for a major depressive episode, nicotine dependence, and alcohol dependence, as well as suicidal ideation. Physical and psychological QoL was significantly more impaired in participants with SPD compared to those without SPD, even after adjustment for comorbidity.
In this large sample, SPD was a prevalent condition associated with co-occurring depression, nicotine, and alcohol dependence. In addition, SPD was independently associated with impaired physical and psychological QoL. Public health efforts toward the early recognition and treatment of SPD are warranted.
This study evaluated the impact of maternal vaccination against rubella on the levels of specific rubella IgG (rIgG) in 198 newborn cord sera samples. Detailed maternal vaccination data were available. Specific rIgG was measured using a commercial enzyme immunoassay. Most mothers (78.8%) had been vaccinated against rubella at least once in their lives. In 15 (7.6%) cord sera samples, the concentration of specific rIgG was below 11 IU/ml, which was classified as seronegative. Statistical analysis using multiple logistic regression (n = 198) showed that newborns of mothers born between 1986 and 1995, and those born to unvaccinated mothers, were more likely to be seronegative (odds ratio (ORs) 5.2 and 4.9, respectively, adjusted for sex and gestational age). For vaccinated mothers (n = 156), those born between 1986 and 1995 were more likely to have seronegative newborns (OR 11.5 adjusting for sex, gestational age and time since last vaccination). Mothers of the 15 (7.6%) seronegative newborns might have been susceptible to rubella during pregnancy. Checking the vaccination status therefore recommended.
Indium oxide (InOx) and indium tin oxide (ITO) thin films were deposited on glass substrates by plasma enhanced reactive thermal evaporation (PERTE) at different substrate temperatures. The films were then submitted to two etching solutions with different chemical reactivity: i) HNO3 (6%), at room temperature; ii) HCl (35%): (40 °Bé) FeCl3 (1:1), at 40 °C. The dependence of the etchability of the films on the structural and deposition conditions is discussed. Previously to etching, structural characterization was made. X-ray diffraction showed the appearance of a peak around 2θ=31° as the deposition temperature increases from room temperature to 190 °C, both for ITO and InOx. AFM surface topography and SEM micrographs of the deposited films are consistent with the structural properties suggested by X-ray spectra: as the deposition temperature increases, the surface changes from a finely grained structure to a material with a larger-sized grain or/and agglomerate structure of the order of 250-300 nm. The roughness Rq varies from 0.74 nm for the amorphous tissue to a maximum of 10.83 nm for the sample with the biggest crystalline grains. Raman spectra are also presented.
Although a national programme for control of visceral leishmaniosis (VL) is being run in Brazil, the disease continues to spread. This programme is essentially based on culling infected dogs from endemic regions. Thus, there is an urgent need to develop other control measures against VL to deter its advance. Here, a subunit vaccine, a recombinant vaccine, an insecticide-impregnated collar and the associations between these measures were evaluated for reducing the incidence of Leishmania infection in dogs. This was through a cohort study conducted in an endemic region of Brazil, considering the incidence and time of total exposure over a period of 1 year. The incidence of VL was estimated by means of serological and molecular diagnostic tests, 180 and 360 days after the application of the control measures. The estimates of the effectiveness (EF) were not significant in any cohort. The EF of the subunit vaccine, the recombinant vaccine and the collar were 26.4%, 32.8% and 57.7% and the upper limit of the 95% confidence interval for EF were 63.7%, 67.9% and 82.5%, respectively. In conclusion, under the conditions of this study, none of the immunogens for VL control was sufficiently effective to protect dogs against infection. On the other hand, use of collars impregnated with insecticide seems to constitute a method with better prognosis, corroborating other studies in this field.
Echocardiographic screening represents an opportunity for reduction in the global burden of rheumatic heart disease. A focussed single-view screening protocol could allow for the rapid training of healthcare providers and screening of patients.
The aim of this study was to determine the sensitivity and specificity of a focussed single-view hand-held echocardiographic protocol for the diagnosis of rheumatic heart disease in children.
A total of nine readers were divided into three reading groups; each interpreted 200 hand-held echocardiography studies retrospectively as screen-positive, if mitral regurgitation ⩾1.5 cm and/or any aortic insufficiency were observed, or screen-negative from a pooled study library. The performance of experts receiving focussed hand-held protocols, non-experts receiving focussed hand-held protocols, and experts receiving complete hand-held protocols were determined in comparison with consensus interpretations on fully functional echocardiography machines.
In all, 587 studies including 76 on definite rheumatic heart disease, 122 on borderline rheumatic heart disease, and 389 on normal cases were available for analysis. The focussed single-view protocol had a sensitivity of 81.1%, specificity of 75.5%, negative predictive value of 88.5%, and a positive predictive value of 63.2%; expert readers had higher specificity (86.1 versus 64.8%, p<0.01) but equal sensitivity. Sensitivity – experts, 96% and non-experts, 95% – and negative predictive value – experts, 99% and non-experts, 98% – were better for definite rheumatic heart disease. False-positive screening studies resulting from erroneous identification of mitral regurgitation and aortic insufficiency colour jets increased with shortened protocols and less experience (p<0.01).
Our data support a focussed screening protocol limited to parasternal long-axis images. This holds promise in making echocardiographic screening more practical in regions where rheumatic heart disease remains endemic.
Euthanasia of infected dogs is one of the measures adopted in Brazil to control visceral leishmaniasis (VL) in endemic areas. To detect infected dogs, animals are screened with the rapid test DPP® Visceral Canine Leishmaniasis for detection of antibodies against K26/K39 fusion antigens of amastigotes (DPP). DPP-positives are confirmed with an immunoenzymatic assay probing soluble antigens of promastigotes (ELISA), while DPP-negatives are considered free of infection. Here, 975 dogs from an endemic region were surveyed by using DPP, ELISA and real-time PCR (qPCR) for the diagnosis of VL. When DPP-negative dogs were tested by qPCR applied in blood and lymph node aspirates, 174/887 (19·6%) were positive in at least one sample. In a second sampling using 115 cases, the DPP-negative dogs were tested by qPCR in blood, lymph node and conjunctival swab samples, and 36/79 (45·6%) were positive in at least one sample. Low-to-moderate pairwise agreement was observed between all possible pair of tests. In conclusion, the official diagnosis of VL in dogs in Brazilian endemic areas failed to accuse an expressive number of infected animals and the impact of the low accuracy of serological tests in the success of euthanasia-based measure for VL control need to be assessed.
The goals of this article are: (i) to understand how individual characteristics affect the likelihood of patients defaulting their pulmonary tuberculosis (PTB) treatment regimens; (ii) to quantify the predictive capacity of these risk factors; and (iii) to quantify and map spatial variation in the risk of defaulting. We used logistic regression models and generalized additive models with a spatial component to determine the odds of default across continental Portugal. We focused on new PTB cases, diagnosed between 2000 and 2013, and included some individual information (sex, age, residence area, alcohol abuse, intravenous drug use, homelessness, HIV, imprisonment status). We found that the global default rate was 4·88%, higher in individuals with well-known risk profiles (males, immigrants, HIV positive, homeless, prisoners, alcohol and drug users). Of specific epidemiological interest was that our geographical analysis found that Portugal's main urban areas (the two biggest cities) and one tourist region have higher default rates compared to the rest of the country, after adjusting for the previously mentioneded risk factors. The challenge of treatment defaulting, either due to other individual non-measured characteristics, healthcare system failure or patient recalcitrance requires further analysis in the spatio-temporal domain. Our findings suggest the presence of significant within-country variation in the risk of defaulting that cannot be explained by these classical individual risk factors alone. The methods we advocate are simple to implement and could easily be applied to other diseases.
In Portugal, the recommended age for the second dose of MMR (MMR2) was changed from 10–13 years to 5–6 years for those born in 1994 and afterwards. This study aimed to assess if MMR schedule and time elapsed from the last dose are associated with the concentration of rubella and mumps IgG antibodies. Three Portuguese birth cohorts (convenience samples) were selected for this study (66, 59 and 41 participants born respectively in 1990–1993, 1994–1995 and 2001–2003). Geometric mean concentrations (GMC) for mumps IgG were respectively 36, 30 and 38 RU/ml (P = 0·236) and for rubella IgG were 18, 20 and 17 IU/ml (P = 0·641). For both specific antibodies, no differences were observed with time since MMR2. Receiving MMR2 at 5–6 or 10–13 years was not associated with concentration of both antibodies. The GMC of rubella IgG was lower in males (P = 0·029). Taking into account previous evidence and the logistics needed to change vaccination schedules, it seems reasonable that sustaining very high coverage with two doses of MMR is currently the most pragmatic way to control mumps and rubella rather than any changes to the schedule.
Millipedes are ecologically important soil organisms and may also be an economically threatening species in rural and urban areas when population outbreaks occur. In order to control infestations commercial formulations of deltamethrin have been commonly applied, even though there are few studies about the effects of such insecticide on millipedes. This paper describes the effects of this insecticide on millipedes showing neurotoxic effects assessed by synapsin labeling and confocal microscopy. Deltamethrin concentrations related to the DL50 of the active ingredient and a field concentration were applied topically in the diplopod Gymnostreptus olivaceus to evaluate the behavior, mortality rate, and synapsin levels in the brain 12, 24, and 48h after contact with deltamethin. The insecticide caused mortality at the higher concentrations employed, in which no change was observed in neurotransmission in the survivors. In contrast, at field concentrations, deltamethrin did not cause any deaths, but triggered significant changes in synapsin levels. The results obtained form the synapsin labeling provide several interpretations suggesting that the isolated application of this tool must be associated with additional tools in order to evaluate biologically induced effects of deltamethrin in an accurate way. In addition, the feasibility of chemical control of millipedes with deltamethrin is questioned.
Portugal, a medium- to low-level endemic country (21·6 cases/100 000 population in 2012), has one of the highest European Union tuberculosis (TB) incidences. Although incidence is declining progressively, the country's heterogeneity in both regional endemics and their evolution suggests the importance of a better understanding of subnational epidemiology to customize TB control efforts. We aimed to update knowledge on municipality-years pulmonary TB incidence clustering, identify areas with different time trends, and show the potential of combining complementary clustering methods in control of infectious diseases. We used national surveillance municipality-level data (mainland Portugal, 2000–2010). Space–time clustering and spatial variation in temporal trends methods were applied. Space–time critical clusters identified (P < 0·001) were still the Lisbon and Oporto regions. The global incidence declined at a 5·81% mean annual percentage change, with high space–time heterogeneity and distinct time trend clusters (P < 0·001). Municipalities with incidences declining more rapidly belonged to critical areas. In particular, the Oporto trend cluster had a consistent −8·98% mean annual percentage change. Large space–time heterogeneities were identified, with critical incidences in the greater Lisbon and Oporto regions, but declining more rapidly in these regions. Oporto showed a consistent, steeper decrease and could represent a good example of local control strategy. Combining results from these approaches gives promise for prospects for infectious disease control and the design of more effective, focused interventions.
Diabetes mellitus (DM) is a major public health problem and its incidence is rising dramatically. The brain, particularly the cerebral cortex, is very susceptible to glucose fluctuations and hyperglycaemia-induced oxidative stress. Tea (Camellia sinensis (L.)) is widely consumed; however, the antidiabetic properties of white tea remain largely unexplored. In the present study, we investigated the effects of daily consumption of white tea on the cerebral cortex of prediabetic rats. The cerebral cortex metabolic profile was evaluated, and the expression levels of GLUT, phosphofructokinase-1, lactate dehydrogenase (LDH) and monocarboxylate transporter 4 were assessed. LDH activity was also determined. The cerebral cortex oxidative profile was determined by evaluating its antioxidant power, lipid peroxidation and protein oxidation levels. Catalase, glutathione, glutamate, N-acetylaspartate, aspartate, choline, γ-aminobutyric acid, taurine and valine contents were determined. Daily consumption of white tea ameliorated glucose tolerance and insulin sensitivity. Moreover, white tea altered the cortex glycolytic profile, modulating GLUT expression and lactate and alanine contents. Finally, white tea consumption restored protein oxidation and lipid peroxidation levels and catalase expression, and improved antioxidant capacity. In conclusion, daily consumption of white tea improved the cerebral cortex metabolic and oxidative profile in prediabetic rats, suggesting it as a good, safe and inexpensive strategy to prevent DM-related effects in the cerebral cortex.