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Photoconductive and third-order nonlinear optical properties exhibited by Cu2ZnSnS4 nanostructures are presented. The samples were synthetized in thin film form by a spray pyrolysis processing route. Distinctions in the photoconductive behavior throughout the samples were clearly noted by modulating their optoelectronic response dependent on electrical frequency. Vectorial two-wave mixing experiments were carried out at a 532 nm wavelength provided by a Nd:YAG laser system to study the optical nonlinearities in the samples. An induced transparency effect was observed during nanosecond single-beam experiments in the nanostructures reported. Quantum and thermal processes were considered to be the main physical mechanism responsible for the photo-electrical phenomena and nonlinear refraction in the nanostructures. Potential applications for developing nanophotonic and nanoelectronic instrumentation systems can be contemplated.

Photocatalytic degradation of methylene blue by graphene decorated titanium dioxide (TiO2) powders heated at different temperatures was analyzed. The powders were prepared by mixing TiO2 with graphene prepared by the modified Hummers method. A thermal treatment was applied to mixed and pure TiO2 powders with the aim of analyze their structural dependence on temperature, and consistently their photocatalytic degradation effect on methylene blue solutions exposed to UV and visible radiation. Structural characterization of the powders was carried out by x-ray diffraction and Raman spectroscopy. When irradiated with UV, the mixed powders showed as high as 87% photocatalytic degradation, while the pure TiO2 reached values of 59%. For visible radiation, as it is expected, the pure TiO2 showed no activity, while the mixture presented degradation of 40%.

Background Infections caused by Candida are an emerging pathology on surgical wards. The aim of the present study was to evaluate the incidence, characteristics, and predictive factors of mortality in patients colonized and/or infected by Candida spp. in this setting. Methods A consecutive series of 105 patients hospitalized on a general surgery ward between 2000 and 2004 were included, and 118 positive cultures for Candida were identified. The variables age, sex, previous medical history, current disease, anemia, ICU stay, type and localization of the microorganism, need for parenteral nutrition, and transfusions were recorded. The primary outcome was in-hospital mortality. A univariate analysis was performed to determine which of these variables were associated with mortality. With a logistic regression model, independent prognostic factors of mortality were determined. Results The prevalence of patients colonized and/or infected by Candida on our surgical ward was 0.98% (CI 95%: 0.79–1.17), and the incidence was 49 cases per 1,000 patient-years. Of the 105 patients in this series, 56 were men (53%) and 49 women (47%); the mean age was 63.8 years (SD ± 15.7). Twelve patients (11.4%) had candidemia. Crude mortality was 23% (24 patients), whereas the mortality attributable to candidemia was 25% (3/12 cases). Anemia ( p  = 0.001); transfusions ( p  = 0.003), and an ICU stay ( p  = 0.002) were associated with mortality. Candidemia was associated with neoplasms ( p  = 0.02) and the infection caused by Candida parapsilosis ( p  = 0.04). The only independent factor related to mortality was the anemia ( p  = 0.028; Odds Ratio: 6.43; 95% CI: 1.23–33.73). Conclusions Colonization and/or infection by Candida spp. in non-ICU hospitalized surgical patients implies a relative high mortality. Anemia is an independent factor for mortality.

Allele frequencies and haplotype analysis have been performed for eight Y-chromosome STRs (DYS19, DYS385 I and II, DYS389 I and II, DYS390, DYS391, DYS392, DYS393). Population data was obtained from a sample of 400 unrelated individuals living in Antioquia (Colombia). A total of 270 different haplotypes were found, and the haplotype diversity was 0.989. The first and second most frequent haplotypes where shared by 8 and 6% of the individuals, respectively.

This study focused on evaluating the antibacterial activity of the cactaceae Acanthocereus tetragonus against the bacteria of high clinical relevance, Escherichia coli and Klebsiella pneumoniae . The principal objective was to validate the potential of this plant, commonly used in traditional medicine, as a functional food against these microbial agents. The methodology consisted of preparing a plant extract and performing a phytochemical analysis to identify and quantify the phenolic compounds by UV-Vis spectrophotometry using gallic acid as a reference standard (0.07 mg/dL). Subsequently, the evaluation of the in vitro activity of this extract was planned through bacterial growth inhibition tests. The results of the chemical analysis confirmed the presence of phenolic compounds and flavonoids, which suggests an expected inhibitory activity against pure strains of the mentioned bacteria. These results support the ethnobotanical use of the plant and underline the viability of future investigations to isolate and characterize the specific active compounds. This advance could lead to the development of new and necessary therapeutic alternatives for the treatment of bacterial infections.

Objectives: To evaluate clinical effect of deep water running(DW R) on non-specific low back pain. Outcome measures were pain, disability,general health and physical fitness. Materials and methods: Experimental, randomized, controlled trial involving 46 persons with CLBP over 15 weekswith two experimental processes, each three times a week. Evidence-basedProgram (EBP, personalized physical exercise program, manual therapy andhealth educa tion) was the common process to which was added 20 minutes ofpersonalized intensity DW R at the aerobic threshold. Measurements were made at the beginning and end of the studyof pain, disability, general health and physical fitness. R esults: The pain of CLBP were homogeneous at baseline.Significant changes between group were don’t found for pain in favour of the EBP+DW R group (p<0.3). The within-group differences were highly significant for all clinical and functional variables. The effect was clinically relevant forpain in the EBP+DW R group (0.70) and in the EBP group (0.58), and for disability degree it was also relevant in theEBP+DW R group (0.48) and relevant for the EBP group (0.36). Conclusion: Significant improvement was seen inCLBP when EBP was complemented with the high-intensity exercise of DW R.

A group of trained and sedentary men performed an incremental graded exercise-test to exhaustion in order to assess the organic response of the two main stress-activated systems: the sympathetic nervous system with its endocrine component (the adrenal medulla), and the hypothalamic-pituitary-adrenal (HPA) axis. Maximal plasma concentrations of ACTH, cortisol and endogenous opioids (beta-endorphins) were obtained at the end of the exercise-test in the trained group. Thus ACTH increased from basal value of 21.25 +/- 2.5 pg/ml to 88.78 +/- 11.8 pg/ml at the end of the exercise (p<0.01); cortisol, from 16.56 microg/dl +/- 4.94 microg/dl to 23.80 +/- 4.57 microg/dl in min 15 of the recovery period (p<0.001); and beta-endorphin from 21.80 +/- 8.33 pmol/ml to 64.36 +/- 9.8 pmol/ml in min 3 of the recovery period (p<0.05). Catecholamine levels were increased from initial values at the end of the effort test in both control and trained groups. Control subjects exhibited a higher responsiveness compared to trained and showed superior intrinsic stimulation of the sympathetic nervous system. These results reveal a different response according to fitness in a physical stress situation.

Studies on austempered nodular cast irons were carried out to establish the optimum isothermic heat treatment at a given chemical composition that rendered the highest fatigue crack propagation resistance. Seven nodular iron chemical compositions with different concentrations of copper, nickel, and or molybdenum were tested at three austempering temperatures achieving ausferritic microstructures. Three-point bend tests for crack growth rates were performed at room temperature in a close loop servo hydraulic machine. Crack opening displacement measurements were performed using a controlled displacement telescope. A simple linear statistical analysis indicated that the lower the austempering isothermal temperature, the higher the fatigue strength of the alloys. Cu and Mo additions along with a good spheroidicity of graphite nodules in the iron favored this effect.

This study presents time-domain and frequency-domain, multiple-input, multiple-output (MIMO) linear system identification techniques that can be used to estimate the dynamic endpoint stiffness of a multijoint limb. The stiffness of a joint or limb arises from a number of physiological mechanisms and is thought to play a fundamental role in the control of posture and movement. Estimates of endpoint stiffness can therefore be used to characterize its modulation during physiological tasks and may provide insight into how the nervous system normally controls motor behavior. Previous MIMO stiffness estimates have focused upon the static stiffness components only or assumed simple parametric models with elastic, viscous, and inertial components. The method presented here captures the full stiffness dynamics during a relatively short experimental trial while assuming only that the system is linear for small perturbations. Simulation studies were performed to investigate the performance of this approach under typical experimental conditions. It was found that a linear MIMO description of endpoint stiffness dynamics was sufficient to describe the displacement responses to small stochastic force perturbations. Distortion of these linear estimates by nonlinear centripetal and Coriolis forces was virtually undetectable for these perturbations. The system identification techniques were also found to be robust in the presence of significant output measurement noise and input coupling. These results indicate that the approach described here will allow the estimation of endpoint stiffness dynamics in an experimentally efficient manner with minimal assumptions about the specific form of these properties.

Abstract Background In 2011, Argentina experienced its highest pertussis incidence and mortality rates of the last decade; 60% of deaths were among infants aged <2 months. In response, a dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine was recommended for all pregnant women at ≥20 weeks of gestation. Although recent studies suggest that maternal Tdap vaccination is effective at preventing infant disease, no data have come from low- or middle-income countries, nor from ones using whole-cell pertussis vaccines for primary immunization. Methods We conducted a matched case-control evaluation to assess the effectiveness of maternal Tdap vaccination in preventing pertussis among infants aged <2 months in Argentina. Pertussis case patients identified from September 2012 to March 2016 at 6 hospital sites and confirmed by polymerase chain reaction testing were included. Five randomly selected controls were matched to each case patient by hospital site and mother’s health district. We used multivariable conditional logistic regression to calculate odds ratios (ORs). Vaccine effectiveness (VE) was estimated as (1 – OR) × 100%. Results Seventy-one case patients and 300 controls were included in the analysis. Forty-nine percent of case patients and 78% of controls had mothers who were vaccinated during pregnancy. Overall Tdap VE was estimated at 80.7% (95% confidence interval, 52.1%–92.2%). We found similar VE whether Tdap was administered during the second or third trimester. Conclusions Tdap vaccination during pregnancy is effective in preventing pertussis in infants aged <2 months in Argentina, with similar effectiveness whether administered during the second or third trimester of pregnancy. Effectiveness of maternal Tdap vaccination in preventing infant pertussis has not been well studied in middle-income countries. Our findings demonstrate that Tdap vaccination during the second or third trimester of pregnancy protects against pertussis in infants aged <2 months in Argentina.