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Kinematic indicators, including certain strain fringes, represent an important group of structures related to the progressive deformation in rocks. The evolution of these fibrous textures can be explained by the combination of multiple mechanisms of deformation and fluid flow, mainly controlled by the orientation of the strain field and the morphology of the grains. In general, the observations are done with an optical microscope and compared with computational models of growth. This work proposes a combination of crystallographic and cathodoluminescence data obtained in rocks from banded iron formations of the Iron Quadrangle in Brazil to represent an example of how complementary analytical techniques can be useful to understand geological problems. The chosen sample exhibits a strain fringe structure of quartz around a clast of magnetite partially transformed into goethite and hematite. Through the crystallographic data it was possible to identify the grain boundary morphology and domains of low deformation areas. On the other hand, the cathodoluminescence signal evidenced the occurrence of grains with a higher concentration of crystalline defects.
The Colombian industrial sector is moving toward alternative forms of treatment of industrial waste, considering that the waste can be a source of raw material in the production chain. Thus, aiming at the decrease in mineral fertilizer use, and maintaining or even raising the crop yield, the sugarcane industry has recently advanced in the composting of the industrial waste and application in the field, both of them being potentially sustainable practices. This manuscript reports the economic benefits and the greenhouse gas (GHG) emissions related to the sugarcane production system in Colombia that has been simulated in this study to evaluate the beneficial effects of reusing industrial waste from ethanol production. This study was performed using the Virtual Sugarcane Biorefinery (VSB) modeling software for the simulation of agricultural and industrial parameters on integrated alternatives for the sugarcane industry. Colombian sugarcane sector was modeled using three scenarios representing agricultural systems that do not use composted industrial waste vs a paired scenario for each condition where composted waste is utilized. Regarding compost and vinasse use as fertilizer and soil conditioner, GHG emissions from the biogenic origin are not included as a reported item in the matrix of GHG emissions of the sugarcane sector. Inputs for the economic and environmental assessment models are based on actual operational data from two mill sites, one located in the traditional sugarcane production region of Cauca River Valley and the other one, on the agricultural expansion region of Llanos Orientales. Here, we have found that the reuse of composted industrial waste is beneficial and provides an economic cost savings of 2–6% per year. However, it also results in an annual increase of 10–20% in the GHG emissions.
An experiment was conducted to evaluate whether dietary reduction and sex class affect nutrient intake, digestibility, purine derivative (PD) excretion and heat tolerance coefficient in lambs. Thirty-five hair lambs (14.5 ± 0.89 kg initial body weight (BW), 2 months old) were used in a completely randomized study with a 3 × 3 factorial arrangement, three sex classes (11 intact males, 12 castrated males and 12 females) and three levels of feeding (ad libitum, 300 and 600 g/kg/dry matter (DM) feed restriction) for 120 days. Intact and castrated males showed higher intakes of DM and neutral detergent fibre corrected for ash and protein (NDFap) than females. At 300 g/kg/DM feed restriction, NDFap digestibility was lower in intact males than in other classes; however, no differences were found between classes when subjected to ad libitum feeding or 600 g/kg/DM. The basal endogenous nitrogen and endogenous urinary losses were highest in intact males. Allantoin, uric acid and PD excretion, as well as PD absorption and microbial protein production were lowest in the animals subjected to 600 g/kg/DM feed restriction. Microbial protein synthesis (MPS) was highest in animals subjected to 600 g/kg/DM feed restriction. The lowest temperatures were observed in animals subjected to 600 g/kg/DM feed restriction. The heat tolerance coefficient was highest in animals subjected to 600 g/kg/DM feed restriction. In conclusion, feed restriction reduced the time spent on feeding and rumination but increased the digestibility of DM. The restriction level of 600 g/kg/DM maximized MPS and infrared thermography indicated an elevated heat tolerance coefficient.
To compare cognitive function among frail and prefrail older adults.
Cross-sectional clinical study.
Fifty-one non-institutionalized older individuals participated in this study.
Cognitive functions were evaluated through Mini-Mental State Examination (Global Cognition), Digit Span Forward (short-term memory), Digit Span Backward (working memory), Verbal Fluency Test (semantic memory/executive function). Data were compared using parametric and non-parametric bivariate tests. Binary logistic regression was used to test a frailty prediction model. Statistical significance was defined as p ≤ 0.01 to compare groups. In the regression model, the p value was set to be ≤0.05.
Statistically significant differences were observed in global cognition, and short-term memory between frail and prefrail individuals (p ≤ 0.01). Global cognition explained 14–19% of frailty's model.
According to our findings, the evaluation of cognitive functions among older persons with frailty and prefrailty provides important complementary information to better manage frailty and its progression.
Phenylcoumarin glucoside (4-PC) is a compound extracted from the plant Hintona latiflora and was studied as inhibitor for AISI 1018 steel corrosion in 3% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques, which may find application as eco-friendly corrosion inhibitors. The 4-PC provides inhibitor properties that protect AISI 1018 low carbon steel against corrosion at low concentrations (5 ppm) obtained by EIS. Polarization studies showed that the inhibitor was of mixed type. The inhibition efficiency by the two electrochemical techniques shows similar results. The inhibitor adsorption was demonstrated to be a combined process (physisorption and chemisorption) according to the Langmuir isotherm.
We studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty body mass (EBM) as the predictors for morphological traits and chemical composition, respectively. We fitted the allometric scaling function by applying the SAS NLMIXED procedure, but to evaluate assumptions regarding variances in morphological and compositional traits, we combined the scaling function with homoscedastic (MOD1), and the heteroscedastic exponential (MOD2) and power-of-the-mean (MOD3) variance functions. We also predicted the ontogenetic growth by using the traditional log-log transformation and back-transformed results into the arithmetic scale (MOD4). We obtained predictions from MOD4 in the arithmetic scale by a two-step process, and evaluated MOD1, MOD2 and MOD3 by a model selection framework, and compared MOD4 with MOD1, MOD2 and MOD3 based on goodness-of-fit measures. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe 10 over 36 traits with a low level of model selection uncertainty. One trait was predicted by averaging the MOD1 and MOD2 variance functions; and nine traits were better described by averaging the MOD2 and MOD3 variance functions. The predictions for other 16 traits were averaged from MOD1, MOD2 and MOD3. However, MOD4 better described 11 traits according to the goodness-of-fit measures. Depending on the variable being analyzed, the body parts and the chemical amounts exhibited the three types of allometric behavior with respect to BM and EBM, that is, positive, negative and isometric ontogenetic growth. Reference BMs, that is, 20, 27, 35 and 45 kg, were used to compute the net protein and energy requirements based on the first derivative of the scaling function, and the results were presented in reference to the EBM and EBM0.75. Both the net protein and energy requirements scaled to EBM0.75 increased from 20 to 45 kg of BM.
Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.
A plausible mechanism underlying flavonoid-associated cognitive effects is increased cerebral blood flow (CBF). However, behavioural and CBF effects following flavanone-rich juice consumption have not been explored. The aim of this study was to investigate whether consumption of flavanone-rich juice is associated with acute cognitive benefits and increased regional CBF in healthy, young adults. An acute, single-blind, randomised, cross-over design was applied with two 500-ml drink conditions – high-flavanone (HF; 70·5 mg) drink and an energy-, and vitamin C- matched, zero-flavanone control. A total of twenty-four healthy young adults aged 18–30 years underwent cognitive testing at baseline and 2-h after drink consumption. A further sixteen, healthy, young adults were recruited for functional MRI assessment, whereby CBF was measured with arterial spin labelling during conscious resting state at baseline as well as 2 and 5 h after drink consumption. The HF drink was associated with significantly increased regional perfusion in the inferior and middle right frontal gyrus at 2 h relative to baseline and the control drink. In addition, the HF drink was associated with significantly improved performance on the Digit Symbol Substitution Test at 2 h relative to baseline and the control drink, but no effects were observed on any other behavioural cognitive tests. These results demonstrate that consumption of flavanone-rich citrus juice in quantities commonly consumed can acutely enhance blood flow to the brain in healthy, young adults. However, further studies are required to establish a direct causal link between increased CBF and enhanced behavioural outcomes following citrus juice ingestion.
The aim of this study was to analyse whether changes in physical activity and body fatness are related to modifications in cardiovascular risk factors among adolescents.
Material and methods
A sample of 89 healthy adolescents was recruited for this study. We assessed habitual physical activity, body fat percentage, arterial thickness, blood sample, and biological maturation. Multivariate models were used to analyse the relationships between independent and dependent variables.
Physical activity (mean difference: 429.4 steps [95% confidence interval=−427 to 1286]) and body fatness (mean difference: −0.7% [95% confidence interval=−1.6–0.2]) remained stable during the study period. Independent of changes in physical activity, for each percentage increase in body fatness, femoral intima-media thickness increased by 0.007 mm (β=0.007 [95% confidence interval=0.001–0.013]). Longitudinal relationships were found for high-density lipoprotein-cholesterol (β=−0.477 mg/dl [95% confidence interval=−0.805 to −0.149]) and triacylglycerol (β=2.329 mg/dl [95% confidence interval=0.275–4.384]).
Changes in body fatness are more important than the amount of physical activity on cardiovascular and metabolic risks.
The aim of this study was to evaluate the effect of dietary lysine on performance, protein deposition and respiratory chain gene expression in male broilers. A total of 252 Cobb 500 broilers were distributed, in a completely randomized design, into four treatments with seven replicates of nine birds per experimental unit. Experimental treatments consisted of diets based on corn and soybean meal, with four levels of digestible lysine: 1.016%, 1.099%, 1.182% and 1.265%. The increase in the level of digestible lysine in the diet provided higher weight gains, feed efficiency and body protein deposition. Birds fed the lowest level of dietary lysine (1.016%) showed a lower expression of genes such as NADH dehydrogenase subunit I (ND1), cytochrome b (CYTB) and cytochrome c oxidase subunits I (COX I), II (COX II) and III (COX III), displaying the worst performance and body protein deposition. This demonstrates the relationship existing between the expression of the evaluated genes and the performance responses. In conclusion, results indicate that broilers fed diets with higher levels of digestible lysine have increased messenger RNA expression of some genes coded in the mitochondrial electron transport chain (ND1, CYTB, COX I, COX II and COX III). It may be stated that diets with proper levels of digestible lysine, within the ‘ideal protein’ concept, promote the expression of genes, which increases the mitochondrial energy, thereby fostering body protein deposition and the performance of broilers in the starter phase.
The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).
In this article, a detailed introduction of the light extinction spectrometry (LES) diagnostics is given. LES allows the direct in situ measurement of the particle size distribution and absolute concentration of dust clouds levitating in plasmas. Using a relatively simple and compact experimental set-up, the dust cloud parameters can be recovered with a good accuracy making minimum assumptions on their physical properties. Special emphases are given to the inversion procedure of light extinction spectra and all the required particle shape, refractive index and light extinction models. The parameter range and the limitations of LES are discussed. Two measurements in low-pressure gas discharges are presented: (i) in a direct-current (DC) glow discharge in which nanoparticles are growing from the sputtering of a tungsten cathode and (ii) in an argon–silane radio-frequency discharge. They demonstrate the capabilities of the LES technique to characterise, in situ and in real-time, the growth dynamics of nanoparticles in the size range 5–100 nm and volume concentrations in the range from a few ppb to a few ppm.
The objective of this study was to verify possible associations between heart rate variability indices and physical activity, body composition, and metabolic and cardiovascular parameters in individuals with type 1 diabetes.
A total of 39 young patients with type 1 diabetes were included. Body composition, physical activity, cardiovascular parameters, and metabolic parameters were assessed. For the heart rate variability analysis, heart rate was recorded beat-by-beat using a Polar S810i heart rate monitor for 30 minutes, with the volunteers in the supine position; subsequently, the following indices were considered: standard deviation of all normal RR intervals; root-mean square of differences between adjacent normal RR intervals in a time interval; percentage of adjacent RR intervals with a difference of duration >50 ms; high frequency component in milliseconds squared; high frequency component in normalised units; standard deviation of the instantaneous variability beat-to-beat; and standard deviation of the long-term variability. The association between the heart rate variability indices and independent variables was verified through linear regression in unadjusted and adjusted models (considering gender and age). The statistical significance was set at 5% and the confidence interval at 95%.
High values of at-rest heart rate were associated with reduced parasympathetic activity and global heart rate variability, and higher values of waist-to-hip ratio were related to lower parasympathetic activity, independent of age or gender.
For young patients with type 1 diabetes, increases in at-rest heart rate values are associated with reduced parasympathetic activity and global heart rate variability, whereas higher waist-to-hip ratio values are related to lower parasympathetic activity, both independent of age and gender.
Autonomic diabetic neuropathy is one of the most common complications of type 1 diabetes mellitus, and studies using heart rate variability to investigate these individuals have shown inconclusive results regarding autonomic nervous system activation.
To investigate the dynamics of heart rate in young subjects with type 1 diabetes mellitus through nonlinear and linear methods of heart rate variability.
We evaluated 20 subjects with type 1 diabetes mellitus and 23 healthy control subjects. We obtained the following nonlinear indices from the recurrence plot: recurrence rate (REC), determinism (DET), and Shanon entropy (ES), and we analysed indices in the frequency (LF and HF in ms2 and normalised units – nu – and LF/HF ratio) and time domains (SDNN and RMSSD), through analysis of 1000 R–R intervals, captured by a heart rate monitor.
There were reduced values (p<0.05) for individuals with type 1 diabetes mellitus compared with healthy subjects in the following indices: DET, REC, ES, RMSSD, SDNN, LF (ms2), and HF (ms2). In relation to the recurrence plot, subjects with type 1 diabetes mellitus demonstrated lower recurrence and greater variation in their plot, inter-group and intra-group, respectively.
Young subjects with type 1 diabetes mellitus have autonomic nervous system behaviour that tends to randomness compared with healthy young subjects. Moreover, this behaviour is related to reduced sympathetic and parasympathetic activity of the autonomic nervous system.
Stegophorus macronectes (Johnston & Mawson, 1942) is a gastrointestinal parasite found in Antarctic seabirds. The original description of the species, which was based only on females, is poor and fragmented with some unclear diagnostic characters. This study provides new morphometric and molecular data on this previously poorly described parasite. Nuclear rDNA sequences (18S, 5.8S, 28S and internal transcribed spacer (ITS) regions) were isolated from S. macronectes specimens collected from the chinstrap penguin Pygoscelis antarctica Forster on Deception Island, Antarctica. Using 18S rDNA sequences, phylogenetic analyses (maximum likelihood, maximum parsimony and Bayesian inference) of the order Spirurida were performed to determine the phylogenetic location of this species. Primer pairs of the ITS regions were designed for genus-level identification of specimens, regardless of their cycle, as an alternative to coprological methods. The utility of this molecular method for identification of morphologically altered specimens is also discussed.
To analyse the relationship between different heart rate variability indices, resting heart rate, and cardiovascular markers in adolescents.
A cross-sectional study was carried out with information from an ongoing cohort study. The sample was composed of 99 adolescents who complied with the following inclusion criteria: aged between 11 and 14 years; enrolled in a school unit of elementary education; absence of any known diseases; no drug consumption; and a formal consent signed by the parents or legal guardians. Weight, height, heart rate variability, lipid profile, inflammatory markers, blood pressure, resting heart rate, intima-media thickness, blood flow, and trunk fatness were measured. Partial correlation and linear regression (expressed by β and 95% confidence intervals [95%CI]) analyses were used to analyse the relationships between the variables.
In the linear regression analysis, even after adjustments for sex, age, trunk fatness, and somatic maturation, parasympathetic activity presented significant correlations with maximum carotid artery blood flow (β=−0.111 [95%CI=−0.216; −0.007]), systolic blood pressure (β=−0.319 [95%CI=−0.638; −0.001]), and resting heat rate (β=−0.005 [95%CI=−0.009; −0.002]).
Parasympathetic activity at rest is inversely related to maximum and minimum blood flow, triacylglycerol levels, and systolic blood pressure. These findings suggest that heart rate variability has the potential to discriminate pre-pubertal adolescents at increased risk.
Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024–4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.