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The objective of this study was to evaluate the fermentative characteristics and chemical composition of cochineal nopal cactus silage additives with urea or Lactobacillus buchneri (LB), as well as the association of both additives in four storage times (7, 15, 60 and 120 days) and during aerobic stability, with evaluations at 0, 48 and 96 h. Four silages were used: no additive, addition of 2% urea, addition of LB and addition of 2% urea and LB. The study was divided into two experiments: the first experiment evaluated the silages at different storage times, and the second experiment evaluated the silages during the aerobic stability test. In both experiments, the experimental design was completely randomized in a factorial scheme (4 × 4 and 4 × 3) with three replicates per treatment. After the ensiling process, lactic acid bacteria predominated in all treatments. The concentration of lactic acid increased significantly from 60 days of ensiling. The concentration of acetic acid varied significantly between the storage times only for the silages treated with urea and LB alone. The silage treated with urea maintained a constant pH value up to 120 days of storage. During the 96 h aerobic stability test, no breaking in the stability of silages was observed. The exclusive or associated use of urea and LB promotes improvement in the fermentative characteristics of cochineal nopal cactus silage, without major alterations in the chemical composition or interfering with the aerobic stability of the silages.
The current study was carried out to examine the effect of cottonseed processing and chitosan supplementation on lamb performance, digestibility and nitrogen digestion. Eighty uncastrated Santa Inês lambs (23 ± 2.2 kg average weight, 4 months old) were distributed in a completely randomized design in a 2 × 2 factorial arrangement that consisted of two cottonseed processing forms (whole or ground) and two chitosan levels (0 or 136 mg/kg live weight). Higher dry matter and organic matter apparent digestibility coefficient (ADC) was achieved with the diets containing the whole cottonseed. Ether extract ADC was higher in the animals fed the chitosan-containing diet. There was an interaction effect on the ADC of neutral detergent fibre corrected for ash and protein, which increased with chitosan inclusion associated with the whole cottonseed. The lambs that received the treatment containing the whole cottonseed showed higher microbial protein synthesis. Chitosan addition increased nitrogen retention. The animals fed chitosan-containing diets showed higher microbial protein synthesis. There was an interaction effect on microbial protein synthesis. Whole cottonseed associated with chitosan in lamb diets increases ether extract ADC and microbial protein synthesis.
Differences in forage nutritive value between morning and afternoon are related to patterns of dehydration and carbohydrate accumulation throughout the day. In this way, management strategies that maximize grazing time during the afternoon could increase forage nutritive value and consequently nutrient intake. The aim of the current experiment was to evaluate the effect of the time of day (06.00 h [designated AM] or 15.00 h [PM]) that cattle are moved to a new paddock on forage nutritive value, grazing behaviour and animal performance of beef cattle on rotationally stocked Marandu palisadegrass (Brachiaria brizantha cv. Marandu Syn. Urochloa brizantha cv. Marandu) pastures. A spring and summer study was conducted in Pirassununga, SP, Brazil from October 2012 to March 2013 (182 days). Treatments were distributed in a randomized complete block design with three replications. Herbage mass, morphological composition, herbage allowance and stocking rates were similar between treatments during spring and summer. Moving animals to a new paddock, regardless of the time of day – 06.00 h (AM) or 15.00 h (PM) – stimulated grazing, modifying the distribution of meals throughout the day. However, compensatory mechanisms among grazing time, bite rate and forage nutritive value throughout the day operated in order to generate similar performance between animals offered a new paddock in the morning or in the afternoon.
Forage is the primary feed source for livestock in tropical regions and energy is one of the most important nutrients for ruminant nutrition. The effects of harvest management of Marandu palisade grass (Brachiaria brizantha cv. Marandu Syn. Urochloa brizantha cv. Marandu) on non-structural carbohydrate (NSC) concentrations were evaluated. A plot (Experiment 1) and a greenhouse study (Experiment 2) were conducted in 2013–14. In Experiment 1, treatments were the factorial arrangement of two harvest times and two vertical canopy layers (upper and intermediate), distributed in a completely randomized design with five replicates. In Experiment 2, treatments were the factorial arrangement of six harvest times and two morphological fractions (leaf blade and pseudostem). In both experiments, NSC concentration increased during the day. Upper and intermediate canopy layers had greater NSC concentration at 15.00 than 06.00 h during spring and summer. In addition, the magnitude of NSC increase was greater in the upper than intermediate canopy layer and in spring than summer. Marandu palisade grass shows greater digestibility in the afternoon than morning, representing an opportunity to optimize energy concentration through harvest management.
This study aimed to evaluate the risk factors for tuberculosis (TB) treatment default in a priority city for disease control in Brazil. A cohort of TB cases diagnosed from 2008 to 2009 was followed up from patients’ entry into three outpatient sites, in Juiz de Fora, Minas Gerais (Brazil), until the recording of the outcomes. Drug addiction, alcoholism and treatment site appeared to be independently associated with default. Current users of crack as the hardest drug (odds ratio (OR) 12·25, 95% confidence interval (CI) 3·04–49·26) were more likely to default than other hard drug users (OR 5·67, 95% CI 1·34–24·03), former users (OR 4·12, 95% CI 1·11–15·20) and those not known to use drugs (reference group). Consumers at high risk of alcoholism (OR 2·94, 95% CI 1·08–7·99) and those treated in an outpatient hospital unit (OR 8·22, 95% CI 2·79–24·21%) also were more likely to default. Our results establish that substance abuse was independently associated with default. National TB programmes might be more likely to achieve their control targets if they include interventions aimed at improving adherence and cure rates, by diagnosing and treating substance abuse concurrently with standard TB therapy.
In the present work, we are investigating the electronic transport mechanism for antimony-doped tin oxide (ATO) ultrathin films produced by a colloidal deposition process (CDP) of nanocrystals synthesized via a solvothermal route in organic medium. The ATO ultrathin films were prepared from nanoparticles containing 9 mol% of Sb and the observed electrical resistivity at room temperature was 1.55, 1.10 × 10−1, and 1.83 × 10−3 Ω cm, respectively, for the 40, 45, and 71 nm films. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy were carried out to investigate the films and electrical resistivity measurements taken in the four-probe mode with temperature ranging from −260 to 27 °C (13–300 K ± 0.1 K). Results show a good data fitting on Mott's two-dimensional (2D) noninteracting variable range hopping for the 45 nm thin film, which is not further observed for the ATO ultrathin films obtained from CDP.
The objective of this study was to determine whether salicylic acid, nitric oxide (NO) and/or feeding by nymphs of the spittlebug Mahanarva spectabilis affect the concentration of total phenolic compounds and the dry matter content of different genotypes of elephant grass (Pennisetum purpureum). Four genotypes of elephant grass with varying levels of resistance to insect attack were treated with 4 mL of salicylic acid (1%) or 2 mL of NO per plant in the presence and the absence of nymphs. We determined the concentration of total phenolic compounds and the percentage dry matter of shoots and roots in the plants. We found that salicylic acid, NO and attack by M. spectabilis did not change significantly the total phenolic compounds concentration in any of the genotypes of elephant grass tested. However, we observed variations in the concentration of phenolic compounds produced between the resistant and susceptible genotypes, both in the shoot, when subjected to salicylic acid or nymphs, and in the roots in the presence of nymphs. Furthermore, the inducers resulted in variation in the dry matter content of the shoots and roots for most of the genotypes tested. Therefore, we conclude that chemical inducers and feeding by M. spectabilis nymphs cannot be used to elicit a resistance response in elephant grass by stimulating the production of phenolic compounds.
Tributyrin (TBT) is a TAG composed of three butyric acids that has beneficial effects on ulcerative colitis due to its trophic, anti-inflammatory, pro-apoptotic and anti-carcinogenic properties. The goal of the present study was to evaluate the efficacy and mechanisms of action of TBT supplementation in the prevention of mucosal damage in experimental colitis. Mice received either a control diet or a TBT-supplemented diet for 15 d. Colitis was induced by dextran sodium sulphate administration during the last 7 d. Mucosal damage and the activation of immune cells and cytokines were determined by histological score, flow cytometry and ELISA. Leucocyte rolling and adhesion were assessed by intravital microscopy. Oxidative stress was determined by monitoring hydroperoxide concentration and evaluating superoxide dismutase (SOD) and catalase activities. Intestinal permeability was analysed using diethylenetriaminepentaacetate acid (99mTcDTPA). Compared with the colitis group, the animals in the colitis+TBT group had reduced mucosal damage and neutrophil and eosinophil mucosal infiltration, which were associated with a higher percentage of regulatory T cells (Treg) and higher levels of transforming growth factor β and IL-10 in the lamina propria. The level of in vivo leucocyte adhesion in the colon microvasculature was reduced after TBT supplementation. A lower level of hydroperoxide and higher levels of SOD and catalase activities were associated with TBT supplementation. TBT-supplemented mice showed reduced intestinal permeability to the levels intermediate between the control and colitis groups. In conclusion, the present results show that TBT has positive effects on colonic restructuring in experimental colitis. Additionally, TBT supplementation changes the immune response by controlling inflammation and regulating the expression of anti-inflammatory cytokines and Treg.
In this work, we studied metal/SnO2 junctions using transport properties. Parameters such as barrier height, ideality factor and series resistance were estimated at different temperatures. Schottky barrier height showed a small deviation of the theoretical value mainly because the barrier was considered fixed as described by ideal thermionic emission-diffusion model. These deviations have been explained by assuming the presence of barrier height inhomogeneities. Such assumption can also explain the high ideality factor as well as the Schottky barrier height and ideality factor dependence on temperature.
Distribution and relative abundance of blue sharks (Prionace glauca) in the southwestern Atlantic Ocean was modeled based on catch-per-unit-effort (CPUE) per 1000 hooks and length frequencies of blue sharks caught by the Brazilian pelagic tuna longline fleet. As a measure of relative abundance, CPUE of blue sharks caught in 58 238 fishing sets by the Brazilian pelagic tuna longline fleet (national and chartered), from 1978 to 2009, was standardized by a Generalized Linear Model (GLM) using three different approaches: i) a negative binomial error structure (log link); ii) the traditional delta lognormal model; and iii) the Tweedie distribution, recently proposed to adjust models with a high proportion of zeros. A cluster analysis using the K-means method was used to identify target species and incorporate it as a factor into the GLM. Cluster analysis grouped the data into six different fishing clusters according to the percentage of target species. Target factor (cluster) was the most important factor explaining the variance in all three CPUE models. The Tweedie model showed a relatively better fit compared to the other models. Blue shark nominal and standardized CPUE showed a relatively stable trend from 1978 to 1995. From 1995 onwards, however, there was an increasing trend in the standardized CPUE, up to a maximum value in 2008. In general, nominal CPUE and standardized CPUE tracked well up until 2000, after which standardized CPUE’s values were at a noticeably lower level than nominal CPUE. Length frequency data were analyzed for 11 932 blue sharks measured as part of the Brazilian onboard observer program operating on the pelagic tuna longline fleet between 2006 and 2008, with sizes ranging from 91 to 224 cm fork length. Overall, blue shark size data showed clear spatial and seasonal distributions for males and females in the southwestern Atlantic Ocean, with juveniles predominantly concentrated in the most southerly latitudes.
Human rotaviruses from the states of Rio de Janeiro, São Paulo and Pará of Brazil were analysed by RNA electrophoresis. At least some bands characteristic of rotavirus double-stranded RNA were detected in 138 (86·8%) of 159 faecal samples in which the presence of rotavirus had been demonstrated by enzyme immunoassay. Of the RNA-positi ve samples, 18 (13·0%) were classified as subgroup 1, 94 (68·1%) as subgroup 2, and 26 (18·8%) could not be classified due to absence of visible bands 10 and 11. Subgroup 2 was more frequent in the three states. All strains of subgroup 1 detected in Rio de Janeiro were associated with a single short-lived school outbreak. All strains of subgroup 1 resembled each other in electrophoretie pattern, irrespective of geographical origin, although minor differences could be detected by co-electrophoresis. Subgroup 2, on the other hand, showed a great degree of electrophoretic heterogeneity and could be divided into several sub-categories.
Sn3O4 nanobelts were grown by a carbothermal evaporation process of SnO2 powders in association with the well known vapour-solid mechanism (VS). The nanobelts crystal structure was investigated by x-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), raman spectroscopy and field emission gun scanning electron microscopy (FEG-SEM). The structural and morphological characterization has confirmed the growth of single crystal nanobelts. The electrical characterization (current-voltage, temperature-dependent resistance curves) of individual Sn3O4 nanobelts was performed at different temperatures and light excitation. The experiments revealed a semiconductor – like character as evidenced by the resistance decreasing at high temperatures. The transport mechanism was identified as the variable range hopping.
In the present work, the screen printing technique has been used to deposit thick films of Zr0.84Y016O1.92 (8YSZ). In order to control the final porosity in view of a specific application (SOFCs or gas sensor), an experimental design based on analysis of variances (ANOVA) has been carried out. From this, we were able to determine the influence of several technological parameters on films porosity and grain size. The films obtained have been analysed with both Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) combined with SEM. We show that only the combination of experimental design and advanced observation technique such as Focused Ion Beam allowed us to extract significant information for the improvement of the deposition process.
Polymer/TiO2 composite solar cells (CSCs) are currently being investigated by academic research groups and industrial companies due to the prospect of achieving good power conversion efficiencies and lifetime stability at a low production cost. We present data of the initial period of operation (up to several hours) of such devices, which show that during this period the CSCs operate in a non-steady state regime. The transient behaviour is accounted for using an equivalent circuit model (ECM) of the photovoltaic device with time-dependent resistors.
Transport number measurements and impedance spectroscopy in controlled temperature and atmosphere were used to investigate the electrical properties of La2Mo2O9 sintered samples. These samples were prepared from nanocrystalline La2Mo2O9 powders as obtained from a new soft chemistry route involving the polymerisation of acrylamide. By means of the electromotive force method measurements, the sintered compound was found mainly oxygen conductor in the range of 400 °C-800 °C with oxide-ion transport number greater than 0.99. The effect of the oxygen partial pressure on the electrical conductivity of La2Mo2O9 was investigated by impedance spectroscopy from 1 to 10−22 atm, showing a highly stable conduction properties up to 10−17 atm at 800 °C.