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There are few studies on the impact of out-of-pocket mental health care expenditures and sociodemographic factors on the probability of Mexican households to incur catastrophic healthcare expenditures (CHE).
The goal of the present study was to estimate the incidence of CHE and its main determinants among the households of persons with mental disorders (MD) in Mexico.
A cross-sectional survey was conducted, including 387 households of persons with MD. The estimation of the CHE was obtained by the health expenditure distribution method. A Logistic Regression (LR) was used to identify the determinants of probability variation of CHE occurrence. Since we expected a proportion of CHE between 20% and 80%, we assume linearity in the probability function, therefore we additionally used an Ordinary Least Squares (OLS) model.
In our sample, the incidence of CHE was 34.8%. The two mental illnesses most frequently associated with CHE were schizophrenia and hyperactive disorder (35.5% and 32.6% of CHE cases, respectively). The regression coefficients showed that for each unit (US$53.77) increase in income, the probability of CHE was reduced by 8.6%, while for each unit increase in hospitalization or medication expenditures, the probability of CHE increased by 12.9% or 19%, respectively. For each additional household member, the probability of CHE increased by 3%, and households with a male patient had a 7% greater probability of CHE.
Household income, household size, hospitalization and medication expenses, and sex of the patient were significant predictors of CHE for households caring for a person with MD.
To analyse the determinants of exclusive breast-feeding (EBF) discontinuation in southeastern Brazil between 2008 and 2013.
Secondary cross-sectional data were analysed from three waves of child feeding surveys conducted in the city of Marília, São Paulo, Brazil, in 2008, 2011 and 2013 (n 1645 children under 6 months). Multivariable Poisson regression models were used to test the association between EBF discontinuation and socio-economic, demographic and biomedical factors in a pooled sample and within each survey wave.
Regionally representative cross-sectional survey from Brazil.
The analytical sample included 1645 infants under 6 months old.
In the pooled sample, 40·7 % of the infants were exclusively breastfed. Between 2008 and 2013, there was a significant increase in C-section (35·1–42·7 %) and pacifier use (41·4–48·8 %). The determinants of EBF discontinuation in the pooled analysis were mothers working outside the home (adjusted prevalence ratio (APR) = 1·10; 95 % CI 1·00, 1·21), first-time mothers (APR = 1·10; 95 % CI 1·01, 1·20), pacifier use (APR = 1·48; 95 % CI 1·36, 1·61) and low birth weight (APR = 1·17; 95 % CI 1·05, 1·32).
Mothers working outside the home, first-time moms, pacifier use and low birth weight were the factors associated with EBF discontinuation. Evidence-based counselling strategies during antenatal and early postpartum care in primary healthcare are needed to address the modifiable determinants of EBF discontinuation and ultimately to improve its rates in southeastern Brazil.
Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.
We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.
This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.
A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = −0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.
Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.
The work focuses on the analysis of electrochemical corrosion in synthetic salt medium of the TiC/Ni-20Cr composite through the polarization curve technique at four exposure times (0, 6, 12 and 24 h). The composite was prepared by liquid infiltration of the liquid alloy into a porous body of TiC. It was found a continuous and homogeneous distribution of the reinforcing material in the interconnected matrix, having a residual porosity of 6.49 vol.%. According to the electrochemical results, in both samples the highest corrosion rate (CR) was obtained at 12 h exposure due to the rupture of the film of the corrosion products, allowing the interaction of chloride ions with the metal surface. The CR of the composite was slightly higher than that of the alloy at all exposure times, so that the presence of the reinforcing particles and the residual porosity reduce the corrosion resistance of the matrix in the composite. The mechanism of corrosion observed in the alloy and the composite was by pitting, however, the composite also presents crevice corrosion by a differential aeration cell mechanism formed between the metal matrix and the ceramic reinforcement, affected by the residual porosity as confirmed by electron microscopy examination.
The implantation and controlled release of growth factors can enhance the proliferation and differentiation of cells that promote new bone formation at defect sites. Therefore, chitosan polymer microspheres were prepared by the water-in-oil emulsion (W/O) method and solvent freeze-drying, using glutaraldehyde as an ionic crosslinker, along with the lyophilization of solvents, to microencapsulate growth factors, preventing denaturation. The microspheres were loaded with recombinant bone morphogenetic protein 2 (Rh-BMP-2). They were spherical in shape, with a rough surface ranging in particle size from 0.4 to 1.6 μm. The yield percentage with respect to the polymer was 70% and the BMP-2 load was regulated by the initial protein dose. BMP-2 release experiments were performed for 7 days in PBS solutions at pH 4 and 7.4. The results showed that the protein release rate was only 2% lower at pH 7.4. BMP-2/chitosan microspheres were compatible with the MG-63 cell line (ATCC®CRL-1427™Homo sapiens bone osteosarcoma) and could be considered drug delivery vehicles in bone tissue engineering applications.
The work presents an electrochemical study of the corrosion behaviour of two TiC/Cu-Ni metal matrix composites with a content of 10 and 20 wt.% Ni immersed in synthetic seawater. The composites were synthesized by a capillary infiltration technique, obtaining dense materials TiC/Cu-10Ni and TiC/Cu-20 Ni with a residual porosity of 1.8 and 1.7%, respectively. The corrosion rate (CR) was evaluated from the techniques of polarization curves (PC), linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS). Electrochemical measurements were carried out under static conditions, ambient temperature and atmospheric pressure at 24 hours exposure in the electrolytic medium. The corrosion rate is affected by the Ni content in the matrix, with less corrosion in the composite with a higher Ni content. The higher content of Ni in the Cu-Ni alloy provides higher passivation and stability to the corrosion products film that are absorbed on the composite surface. Microscopic examination (SEM) showed a characteristic morphology of a corrosion mechanism of the localized type (pits and crevices) generated by a differential aeration, where the TiC/Cu-10Ni composite showed greater degradation.
This research shows the development of alternative Cu-based materials for applications where enhanced thermal properties are desired. Cu/AlN composites were fabricated from mixtures of pure Cu and copper plated AlN-Cu composite powders. The ceramic phase was added in amounts of 10, 20 and 30 vol.% and the mixtures sintered by pulsed electric current sintering process (PECS). The results showed that the AlN particles are homogeneously distributed in the copper matrix and that the true contacts between hard particles are reduced because of the deposited copper on their surfaces, improving the connectivity of the matrix phase and bonding at the metal-ceramic interface. The relative density of the Cu/AlN composites was major than 97% in all cases. Thermal conductivity of the composites was high and decreased with the ceramic content from 359 to 194 W/mK, for 10 and 30% AlN, respectively. The coefficient of thermal expansion followed a lineal behavior with temperature and is also reduced with the ceramic content.
This article examines the circumstances under which civilians, using protests as a mechanism, alter the strategic use of violence by armed actors (rebels and state forces). By examining the civil war in Colombia between 1988 and 2005, this study finds that combatants decrease their attacks against the population when civilians protest against the enemy. Combatants interpret such demonstrations as costly signals of loyalty. Furthermore, when insurgents are the target of the protests, insurgents increase repression against civilians as rebels get stronger. In contrast, state forces (and paramilitaries) compensate for their weakness in the area by multiplying civilian victims. Both state forces and rebels, however, are likely to decrease violence against civilians when civilians protest against both parties in contested zones. In such contexts, armed actors are likely to refrain from retaliation because any violence might drive noncombatants toward the enemy.
The recent development of genetic methods allows the delineation of species boundaries, especially in organisms where morphological characters are not reliable to differentiate species. However, few empirical studies have used these tools to delineate species among parasitic metazoans. Here we investigate the species boundaries of Clinostomum, a cosmopolitan trematode genus with complex life cycle. We sequenced a mitochondrial [cytochrome c oxidase subunit I (COI)] gene for multiple individuals (adults and metacercariae) from Middle-America. Bayesian phylogenetic analysis of the COI uncovered five reciprocally monophyletic clades. COI sequences were then explored using the Automatic Barcode Gap Discovery to identify putative species; this species delimitation method recognized six species. A subsample was sequenced for a nuclear gene (ITS1, 5·8S, ITS2), and a concatenated phylogenetic analysis was performed through Bayesian inference. The species delimitation of Middle-American Clinostomum was finally validated using a multispecies coalescent analysis (species tree). In total, five putative species are recognized among our samples. Mapping the second intermediate hosts (fish) onto the species tree suggests that metacercariae of these five species exhibit some level of host specificity towards their fish intermediate host (at the family level), irrespective of geographical distribution.
In this article we evaluate ∼48km2 of airborne lidar data collected at a target density of 15 laser shots/m in central Yucatán, Mexico. This area covers parts of the sites of Chichén Itzá and Yaxuná, a kilometer-wide transect between these two sites, and a transect along the first few kilometers of Sacbé 1 from Yaxuná to Cobá. The results of our ground validation and mapping demonstrate that not all sizable archaeological features can be detected in the lidar images due to: (1) the slightly rolling topography interspersed with 1-6 m-high bedrock hummocks, which morphologically mimic house mounds, further complicated by the presence of low foundations; (2) the complex forest structure in central Yucatán, which has particularly dense near-ground understory resulting in a high number of mixed-signal ground and low vegetation returns which reduces the fidelity and accuracy of the bare-earth digital elevation models; and (3) the predominance of low archaeological features difficult to discern from the textural noise of the near-ground vegetation. In this article we explore different visualization techniques to increase the identification of cultural features, but we conclude that, in this portion of the Maya region, lidar should be used as a complement to traditional on-the-ground survey techniques.
The sea star Anasterias minuta broods the embryos in the oral region; embryos then block the mouth and prevent the parent from taking up nutrients during the brooding period. Here, we analysed content of carbohydrates in different organs as well as in eggs, embryos and juveniles of A. minuta. We found that these biochemical components are used mainly by the pyloric caeca and the body wall as reserve substances to endure the periods of reduced consumption rates of non-brooding females and males and the long-term starvation of brooding females. The ability to translocate carbohydrates from females to embryos and juveniles observed in other species of sea stars was not confirmed.
Ni-Co/Al2O3 composites with alumina particles below 0.53 µm in size were electrochemically deposited on carbon steel AISI-O1 substrates. The influence of current density (2, 3, 4 and 5 mA/cm2) on the microstructure and adhesion behavior was investigated. It was found that the micro-hardness of the surface increased in 90% with respect to the plain substrate. SEM examination revealed an increased thickness from 3.7 to 10.7 µm at current density of 2 and 5 mA/cm2, respectively. The Co/Ni weight ratio in the coatings was determined by atomic absorption spectroscopy (AAS); the content of Co and Ni at 2 mA/cm2 were 42.4 %Co and 57.6 %Ni, while at 5 mA/cm2 were 44.5%Co and 55.5%Ni. The adhesion of the coatings was evaluated qualitatively according to the VDI 3198 norm; in all the cases, the adhesion was more than acceptable since no cracks or detachments were observed in the periphery of the marks. Details on the synthesis and properties of the Ni-Co/Al2O3 composite coatings are presented together with the excellent properties they show despite of their thin thickness.
Angola is a large country with a relatively small population and abundant natural resources, including oil reserves. The high price fetched by oil, the mainstay of the Angolan economy, on international markets has helped this leading producer attain growth rates that are among the highest in the world. However, Angola is also noted for its unequal distribution of wealth and notorious political corruption. This article seeks to explore this paradox within the framework of the so-called resource curse theory and analyze the role played by the oil industry in the process.
A distributed control mechanism for ground moving nonholonomic robots is proposed. It enables a group of mobile robots to autonomously manage formation shapes while navigating through environments with obstacles. The mechanism consists of two stages, with the first being formation control that allows basic formation shapes to be maintained without the need of any inter-robot communication. It is followed by obstacle avoidance, which is designed with maintaining the formation in mind. Every robot is capable of performing basic obstacle avoidance by itself. However, to ensure that the formation shape is maintained, formation scaling is implemented. If the formation fails to hold its shape when navigating through environments with obstacles, formation morphing has been incorporated to preserve the interconnectivity of the robots, thus reducing the possibility of losing robots from the formation.
The algorithm has been implemented on a nonholonomic multi-robot system for empirical analysis. Experimental results demonstrate formations completing an obstacle course within 12 s with zero collisions. Furthermore, the system is capable of withstanding up to 25% sensor noise.
In this work we study the interfaces between the Mott insulator LaMnO3 (LMO) and the band insulator SrTiO3 (STO) in epitaxially grown superlattices with different thickness ratios and different transport and magnetic behaviors. Using atomic resolution electron energy-loss spectral imaging, we analyze simultaneously the structural and chemical properties of these interfaces. We find changes in the oxygen octahedral tilts within the LaMnO3 layers when the thickness ratio between the manganite and the titanate layers is varied. Superlattices with thick LMO and ultrathin STO layers present unexpected octahedral tilts in the STO, along with a small amount of oxygen vacancies. On the other hand, thick STO layers exhibit undistorted octahedra while the LMO layers present reduced O octahedral distortions near the interfaces. These findings are discussed in view of the transport and magnetic differences found in previous studies.
Body image dissatisfaction (BID) in school-age children is positively associated with weight status in cross-sectional studies; however, it is uncertain whether BID is a risk factor for the development of adiposity over time. The aim of the present study was to examine the association of BID with changes in BMI in school-age children.
Longitudinal study. At recruitment, children were asked to indicate the silhouette that most closely represented their current and desired body shapes using child-adapted Stunkard scales. Baseline BID was calculated as the difference of current minus desired body image. Height and weight were measured at recruitment and then annually for a median of 2·5 years. Sex-specific BMI-for-age curves were estimated by levels of baseline BID, using mixed-effects models with restricted cubic splines.
Public primary schools in Bogotá, Colombia.
Six hundred and twenty-nine children aged 5–12 years.
In multivariable analyses, thin boys who desired to be thinner gained an estimated 5·8 kg/m2 more BMI from age 6 to 14 years than boys without BID (P = 0·0004). Heavy boys who desired to be heavier or thinner gained significantly more BMI than boys without BID (P = 0·003 and P = 0·007, respectively). Thin girls who desired to be heavier or thinner gained significantly less BMI than girls without BID (P = 0·0008 and P = 0·05, respectively), whereas heavy girls who desired to be heavier gained an estimated 4·8 kg/m2 less BMI than girls without BID (P = 0·0006). BID was not related to BMI change in normal-weight children.
BID is associated with BMI trajectories of school-age children in a sex- and weight-specific manner.