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Phosphate rocks are the main phosphorus source, a key nutrient for crop production in the tropics. Besides phosphorus and calcium, phosphate rocks may contain organic matter and heavy metals, such as cadmium and lead, depending on their geological origin. In general, phosphate rocks from sedimentary origin present higher content of heavy metal than igneous phosphate rocks. The world phosphate rock consumption of sedimentary and igneous origin is around 75 and 20%, respectively. The use of cadmium containing phosphate rocks as fertilizers can bring risks to the environment. The objective of this work was to investigate the influence of partial oxidation of organic matter with H 2 O 2 as a pre-treatment to improve cadmium leaching from sedimentary phosphate with high organic matter content. As leaching agents, MgCl 2 , KCl, Na 2 -EDTA and citric acid solutions were tested. When cadmium removal was carried out with a 0.1 mol L −1 Na 2 -EDTA solution without partial oxidation of organic matter, its content in the sample was reduced from 49.5 to 38.5 mg kg −1 , after 5 h, corresponding to a removal of only 23%. On the other hand, when cadmium leaching was carried out after organic matter oxidation with a 40 mg L −1 H 2 O 2 solution, the cadmium content in the sample was reduced from 49.5 to 22.5 mg kg −1 , corresponding to a removal of 54.5%, turning it more adequate to be used as fertilizer. [ABSTRACT FROM AUTHOR]

Phosphate fertilizers are critical for crop production in tropical soils, which are known for having high phosphate-fixing capacity and aluminum saturation, as well as low pH and calcium contents. Fluorine is a component of many phosphate rocks used to make phosphate fertilizers, via a process that generates hexafluorosilicic acid (H 2 SiF 6 ). While many treatment technologies have been proposed for removal of fluorine in industrial facilities, little attention has been given to a process of neutralizing H 2 SiF 6 with calcium oxide aiming to find out an alternative and sustainable use of a by-product with a great potential for beneficial use in tropical agriculture. This study evaluated the effect of a by-product of phosphoric acid production (fluorite with silicon oxide, hereafter called AgroSiCa) on soil properties as well as on growth of soybean and corn. Two experiments (2 crops) were conducted under greenhouse conditions in a completely randomized 3 × 5 × 2 × 3 factorial design as follows: three soils (Red Latosol, Red-Yellow Latosol, and Cambisol), five doses of AgroSiCa (0; 0.5; 1.0; 2.0; 4.0 t ha −1 ), two doses of phosphorus (2 × %clay and 4 × %clay), with three replicates, totaling 90 plots for each experiment. The application of AgroSiCa resulted in a slight increase of soil pH. Significant increases in calcium, phosphate, and silicon levels in soil solution and in shoots of maize and soybean were observed at all doses of AgroSiCa. We also found very low levels of fluoride in all soil leachates. Significant reduction of labile aluminum was found in all soils after the cultivation of maize and soybean. In sum, AgroSiCa improved soil properties and contributed to a better growth of both crops. Our results show that reacting H 2 SiF 6 derived from the wet-process phosphoric acid production with calcium oxide leads to a by-product with potential for agricultural use, especially when applied in highly-weathered soils. Besides providing calcium and silicon to plants, the use of such by-product in soils with high phosphate-fixing capacity and high aluminum saturation delivers additional benefits, since fluoride and silicon can play an important role in improving soil conditions due to the formation of less plant-toxic forms of aluminum, as well as upon decreasing phosphate fixation, thus improving root development and making fertilizer-derived phosphate more available for plant growth. [ABSTRACT FROM AUTHOR]

Saccadic eye movements reduce body sway, yet visually pursuing a moving dot seems to increase body sway. However, how these two types of eye movements affect postural control remains ambiguous, particularly for smooth pursuit eye movements. The aim of this study was to examine the effects of saccade and smooth pursuit eye movements on body sway magnitude during low and high frequencies. Ten young adults (19.5 ± 1.9 years) participants were required to stand upright, barefoot for 70 s using a bipedal stance, with feet hip width apart, fixating or pursuing a target that was displayed on a monitor positioned 100 cm away from their eyes. Each participant performed three trials using both types of eye movements, in particular, slow and fast saccades, and slow and fast smooth pursuit movements. Body sway was obtained using reflective markers attached to a participant’s head and trunk, which were recorded by two video cameras. The results indicated that body sway was reduced during both saccadic eye movements and smooth pursuit movements when compared to fixation, independent of visual frequencies. These results suggested similarities in the control of saccades and smooth pursuit on postural control. [ABSTRACT FROM AUTHOR]

[Display omitted] The aqueous solubility of active pharmaceutical ingredients is one of the most important features to be considered during the development of parenteral formulations in the pharmaceutical industry. Computational modelling has become in the last years an integral part of pharmaceutical development. In this context, ab initio computational models, such as COnductor-like Screening MOdel (COSMO), have been proposed as promising tools for the prediction of results without the effective use of resources. Nevertheless, despite the clear evaluation of computational resources, some authors had not achieved satisfying results and new calculations and algorithms have been proposed over the years to improve the outcomes. In the development and production of aqueous parenteral formulations, the solubility of Active Pharmaceutical Ingredients (APIs) in an aqueous and biocompatible vehicle is a decisive step. This work aims to study the hypothesis that COSMO models could be useful in the development of new parenteral formulations, mainly aqueous ones. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to investigate the influence of dietary potassium on the sodium effect on blood pressure (BP) in the general population and the adherence of current recommendations for sodium and potassium intake. An overnight (12-hour) urine sample was collected in a population-based study to investigate cardiovascular risk. A sub-sample of 1285 subjects (age range, 25–64 years) free from any medication interfering with BP or potassium excretion was studied. Of the participants, 86.0% consumed over 6 g of salt/day and 87.7% less than the recommended intake of potassium (4.7 g). Potassium excretion and the sodium to potassium ratio were significantly related to systolic and diastolic BP only in subjects consuming more than 6 g/day of salt. Subjects in the highest sodium to potassium ratio quartile (surrogate of unhealthy diet) presented 8 mm Hg and 7 mm Hg higher values of systolic and diastolic BP, respectively, when compared with the first quartile, while individuals in the fourth quartile of urinary potassium excretion (healthier diet) showed 6 mm Hg and 4 mm Hg lower systolic and diastolic BP, respectively, compared with the first quartile. Our data indicate that when people have an increased intake of potassium, high intake of sodium is not associated with higher BP. [Copyright &y& Elsevier]

Abstract: Given a time-dependent solution of the Navier–Stokes equations and an arbitrary open subset of the boundary, the existence of a boundary control, supported in the given subset, that drives the system to the given solution in finite time is proven. Null controllability of the Oseen system is investigated as well, and continuity results of the driving control on the initial data are derived. [Copyright &y& Elsevier]

Previous studies have demonstrated that supervised strength training (ST) or walking training (WT) improve walking capacity in patients with claudication. However, it remains unknown whether these improvements would be sustained over a subsequent unsupervised period. This article reports the findings of a study to analyze whether the improvements in walking capacity, achieved with a supervised ST or WT, would be sustained over a subsequent unsupervised therapy period in patients with claudication. Patients were initially randomized to supervised exercise consisting of ST (n = 15) or WT (n = 15) for 12 weeks. After this period, 12 patients in each group consented to be followed for an additional 12 weeks of unsupervised therapy. Initial claudication distance (ICD) and total walking distance (TWD) were measured at baseline, after the supervised period (Week 12) and after the unsupervised period (Week 24). In comparison with baseline values, both groups similarly increased ICD and TWD at Week 12. From Week 12 to Week 24, both groups similarly decreased ICD (ST: -55 ± 110 m and WT: -82 ± 142 m, P =.04) and TWD (ST: -68 ± 186 m and WT: -128 ± 112 m, P < .01). However, in both groups, ICD (ST: +126 ± 149 m and WT: +50 ± 167 m, P = .01) and TWD (ST: +104 ± 162 m and WT: +45 ± 139 m, P =.01) at Week 24 remained greater than baseline values. The conclusion is that supervised ST or WT followed by an unsupervised therapy period similarly decreased walking capacity in patients with claudication. However, after the unsupervised period, walking capacity remained at a higher level than before the onset of the supervised exercise-training period. [Copyright &y& Elsevier]

Abstract: Background: Insulin resistance and obesity are recognized as left ventricular (LV) mass determinants independent of blood pressure (BP). Prevalence of LV hypertrophy (LVH) and the relationship between LV mass to body composition and metabolic variables were evaluated in normotensive individuals as participants of a population-based study. Methods: LV mass was measured using the second harmonic image by M-mode 2D guided echocardiography in 326 normotensive subjects (mean 47±9.4 years). Fasting serum lipids and glucose, BP, body composition and waist circumference (WC) were recorded during a clinic visit. Results: Applying a normalization criterion not related to body weight (g/height raised to the power 2.7) and the cut-off points of 47.7 (men) and 46.6 g/m2.7 (women), LVH was found in 7.9% of the sample. Univariate analysis showed LV mass (g/m2.7) related to age, body mass index (BMI), WC, fat and lean body mass, systolic and diastolic BP, and metabolic variables (cholesterol, HDL-c, triglycerides and glucose). In multivariate analysis only BMI and age-adjusted systolic BP remained as independent predictors of LV mass, explaining 31% and 5% of its variability. Removing BMI from the model, WC, age-adjusted systolic BP and lean mass remained independent predictors, explaining 25.0%, 4.0% and 1.5% of LV mass variability, respectively. After sex stratification, LV mass predictors were WC (8%) and systolic BP (5%) in men and WC (36%) and systolic BP (3%) in women. Conclusion: BMI in general and particularly increased abdominal adiposity (WC as surrogate) seems to account for most of LV mass increase in normotensive individuals, mainly in women. [Copyright &y& Elsevier]

A new output injection operator and a new feedback control operator are proposed to estimate and stabilize the state of linear nonautonomous parabolic equations. The proposed operators are time-independent and involve appropriately constructed oblique projections. Firstly, it is shown the estimating property of the dynamical Luenberger observer and the stabilizing property of the feedback controller. Then, it is shown the stability of the observer-controller coupled system, where the control input is dynamically constructed from the measured output. The numbers of actuators and sensors are finite. Finally, results of simulations are presented showing the stability of the closed-loop observer-controller coupled system. [ABSTRACT FROM AUTHOR]

• Mean sway amplitude is lower in the wearing Eye-Tracker than non-Eye-Tracker trials. • Mean sway velocity is slower in the wearing Eye-Tracker than non-Eye-Tracker trials. • Wearing a head-mounted eye tracker may attenuate body sway of young adults. • Body sway was minimized in order to aid the performance of the saccades. • Postural adjustments in different visual tasks were preserved during Eye-Tracker. This study investigated the effects of wearing a head-mounted eye tracker on upright balance during different visual tasks. Twenty five young adults stood upright on a force plate while performing the visual tasks of fixation, horizontal saccades, and eyes closed, during eighteen trials wearing or not a head-mounted eye tracker. While wearing the eye tracker, participants showed a reduction in mean sway amplitude and velocity of the CoP in the AP and ML directions and more regular CoP fluctuations, in the ML axis in all conditions. Higher mean sway amplitude and velocity of CoP were observed during eyes closed than fixation and saccades. Moreover, horizontal saccades reduced mean sway velocity of CoP compared to fixation. Therefore, wearing the eye tracker minimized the body sway of young adults; however, visual task-related effects on postural stability remained unchanged. [ABSTRACT FROM AUTHOR]

Postural control is influenced by eye movements. Gaze fixation, which comprises a component of ocular vergence, is important in the acquisition of highly specific task information, but its relation to postural control is little investigated. The aim of the study was to investigate the effects of gaze fixation position (central and lateral fixations) on postural sway in young adults. Forty young adults with ages ranging from 20 to 35 years were invited to participate in the study. Postural sway was measured in quiet stance in bipedal support in three 60-s trials under the following conditions: gaze fixation on a target positioned in front of participant, gaze fixation on a target positioned on right side of participant, and gaze fixation on a target positioned on left side of participant. The following center of pressure parameters (COP) in the anteroposterior (AP) and mediolateral directions (ML) were analyzed for each of the trials: body sway displacement, mean velocity of sway, root mean square (RMS) of sway, and median frequency. In addition, detrended fluctuation analysis (DFA) exponent, in anteroposterior and medio-lateral directions, was calculated. The COP presented greater AP and ML displacement (p < 0.03, effect size = 1.37; and p < 0.03, effect size = 1.64, respectively) and RMS AP and ML (p < 0.04, effect size = 1.66; and p < 0.02, effect size = 2.50, respectively) for lateral gaze fixation compared to central gaze fixation. These results suggest that gaze fixation on a laterally positioned target increases body sway in anteroposterior and mediolateral directions. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the motor and visual strategies used when walking around (circumvention) an obstacle in patients with Parkinson's disease (PD), in addition to the effects of dopaminergic medication on these strategies. To answer the study question, people with PD (15) and neurologically healthy individuals (15 - CG) performed the task of obstacle circumvention during walking (5 trials of unobstructed walking and obstacle circumvention). The following parameters were analyzed: body clearance (longer mediolateral distance during obstacle circumvention of the center of mass -CoM- to the obstacle), horizontal distance (distance of the CoM at the beginning of obstacle circumvention to the obstacle), circumvention strategy ("lead-out" or "lead-in" strategy), spatial-temporal of each step, and number of fixations, the mean duration of the fixations and time of fixations according to areas of interest. In addition, the variability of each parameter was calculated. The results indicated that people with PD and the CG presented similar obstacle circumvention strategies (no differences between groups for body clearance, horizontal distance to obstacle, or obstacle circumvention strategy), but the groups used different adjustments to perform these strategies (people with PD performed adjustments during both the approach and circumvention steps and presented greater visual dependence on the obstacle; the CG adjusted only the final step before obstacle circumvention). Moreover, without dopaminergic medication, people with PD reduced body clearance and increased the use of a "lead-out" strategy, variability in spatial-temporal parameters, and dependency on obstacle information, increasing the risk of contact with the obstacle during circumvention. [ABSTRACT FROM AUTHOR]

Summary: Aim: The purpose of this study was to provide normal values for maximum phonation time (MPT) and the s/z ratio by examining 1660 children aged 4–12 years and without vocal signs or symptoms. Methods: The technique was based on the sustained emission of the /a/ vowel and fricatives /s/ and /z/. Results: The average of the MPT in children of the different age groups was as follows: 6.09 seconds for the age group 4–6 years (males, 5.97; female, 6.21 seconds), 7.94 seconds for the age group 7–9 years (males, 8.07; females, 7.79 seconds), and 8.98 for the age group 10–12 years (males, 9.05; females, 8.92 seconds). The overall average for males was 7.78 and females 7.64 seconds. The s/z ratio was near 1.0 in most children but above 1.2 in 133 children and below 0.8 in 133 children. Conclusion: These values of MPT and s/z ratio can be used as normative in further pediatric studies. [Copyright &y& Elsevier]

Abstract: Vocal nodules constitute the major cause of dysphonia during childhood. Auditory-perceptual and acoustic vocal analyses have been used to differentiate vocal nodules from normal voice in children. Purpose: To study the value of auditory-perceptual and acoustic vocal analyses in assessments of children with nodules. Design: Diagnostic test study. Patients and interventions: A comparative study was carried out including 100 children with videolaryngoscopic diagnosis of vocal nodules (nodule group-NG); and 100 children without vocal symptoms and with normal videolaryngoscopic exams (control group-CG). The age range of both groups was between 4 and 11 years. All children underwent auditory-perceptual vocal analyses (GRBASI scale); maximum phonation time and s/z ratio were calculated, and acoustic vocal analysis (MDVP software) were carried out. Results: There was no difference in the values of maximum phonation time and s/z ratio between groups. Auditory-perceptual analysis indicated greater compromising of voice parameters for NG, compared to CG: G (79 versus 24), R (53 versus 3), B (67 versus 23) and S (35 versus 1). The values of acoustic parameters jitter, PPQ, shimmer, APQ, NHR and SPI were higher for NG for CG. The parameter f0 did not differ between groups. Conclusion: Compromising of auditory-perceptual (G, R, B and S) and acoustic vocal parameters (jitter, PPQ, shimmer, APQ, NHR and SPI) was greater for children with nodules than for those of the control group, which makes them important methods for assessing child dysphonia. [Copyright &y& Elsevier]

Abstract: A high salt diet is a known risk factor for cardiovascular diseases that leads to cardiac hypertrophy and creates a substrate for arrhythmias and sudden death. However, acute arrhythmogenesis after infarction has not been studied. Male Wistar rats (21days) received drinking water (MI) or 1% NaCl solution (MI-Salt-C) for 4weeks. Water was given to another group for 4weeks, and on the day before surgery, animals received a 1% NaCl solution (MI-Salt-A). Non-invasive systolic blood pressure (SBP) was obtained before surgery. Myocardial infarction (MI) was produced by permanent occlusion of the left coronary artery. Electrocardiogram was monitored during the first 30min post-occlusion to evaluate arrhythmias. Although SBP was not altered by salt intake (SHAM: 114±2, MI: 112±2, MI-Salt-C: 115±2, MI-Salt-A: 116±4mm Hg), ventricular hypertrophy was observed in the animals receiving chronic salt diet (SHAM: 0.22±0.008, MI: 0.23±0.007, MI-Salt-C: 0.28±0.01; MI-Salt-A: 0.23±0.01g/cm; P <0.05). Ventricular premature beats increased in both salt-loaded groups compared to MI group (MI: 805±81, MI-Salt-C: 1145±98; MI-Salt-A: 1023±77; P <0.05). Atrioventricular blockade was only observed in animals subjected to high salt intake (MI-Salt-C: 38.9%; MI-Salt-A: 42.1%). High salt intake was associated with increased post-infarct arrhythmias; however, this effect was unrelated to ventricular hypertrophy. [Copyright &y& Elsevier]

• Postural sway was reduced to accomplish visually guided horizontal saccades; • CoP sway was higher in the moving visual scenario than in stationary condition; • Performing predictable or unpredictable saccades in the moving scenario did not affect the visual-motor coupling; • But variability of this coupling was decreased during unpredictable saccades. • Unpredictable saccades decrease flexibility to down-weight unreliable visual information in moving scenario. This study investigated the modulation of center of pressure (CoP) displacements of young adults as they performed predictable and unpredictable saccadic eye movements in stationary and moving visual scenarios. We also examined whether the relationship between CoP displacements and visual stimulus, provided by the moving scenario, and gaze control itself, are affected by the demands of the saccadic tasks. Fifteen young adults (20.53 ± 2.1 years old) stood upright on a force plate, inside a moving room, wearing an eye tracker while performing three tasks: gaze fixation (fixating on a target in the center of the screen), predictable task (saccades while following a target which continuously appeared and disappeared on the right and left sides), and unpredictable task (similar to the previous task, but the participants did not know which side the target would appear on). For saccadic tasks, the target appeared at a frequency of 1.1 Hz and with eccentricity of 11.5 degrees of visual angle. Two blocks of six trials were performed: in the first block, the room remained stationary and in the second, it oscillated (0.6 cm amplitude; 0.2 Hz frequency). Mean amplitude of CoP displacements was lower in the saccadic tasks compared to the gaze fixation, in both conditions; and higher in the moving scenario than in the stationary condition. Variability of CoP displacements was lower in the unpredictable saccades than gaze fixation task. Saccade reaction time was longer in the unpredictable than predictable task. We conclude that CoP displacements are reduced to facilitate performance of the saccadic tasks regardless of conditions and task complexity. Furthermore, lower variability suggests modulation of CoP displacements to deal with the increased attentional demands associated with the performance of the unpredictable saccades, indicating the important role of visual task constraints in postural control. [ABSTRACT FROM AUTHOR]

Abstract: We used the fabrics of two granite plutons and U/Pb (SHRIMP) zircon ages to constrain the tectonic evolution of the E-trending Patos shear zone (Borborema Province, NE Brazil). The pre-tectonic Teixeira batholith consists of an amphibole leucogranite locally with aegirine-augite. Zircons from a syenogranite yielded crystallization ages of 591±5Ma. The batholith fabrics were determined by anisotropy of magnetic susceptibility (AMS) and mineral shape preferred orientation. The fabrics support pre-transcurrent batholith emplacement, as evidenced by: (i) magmatic/magnetic fabrics in low susceptibility (<0.35mSI) leucogranites highly discordant to the regional host rock structure, and (ii) concordant magnetic fabrics restricted to high susceptibility (>1mSI) corridors connected to shear zones branching off from Patos. One of these satellite shear zones controlled the syntectonic emplacement of the Serra Redonda pluton, which yields a crystallization age of 576±3Ma. This late shearing event marks the peak regional deformation that, south of Patos, was coupled to crustal shortening nearly perpendicular to the shear belt. The chronology of the deformational events indicates that the major shear zones of the eastern Borborema are late structures active after the crustal blocks amalgamated. [Copyright &y& Elsevier]

The synthesis of 2H-chromenes based on a fluorenone nucleus is described. Whereas 2,2-diphenyl-2H-pyranofluorenones 4–7 and dicyanomethylidene-2H-pyranofluorenes 8–10 do not exhibit photochromism, 2,2-diphenyl-2H-pyranofluorenols exhibit photochromic behaviour. The spectrokinetic properties of these compounds in solution are reported. [Copyright &y& Elsevier]

Background: People with Parkinson's disease (PD) do not differ from neurologically healthy individuals in obstacle circumvention during walking, therefore they are able to use visual feedback adequately to control motor behavior in this task. However, individuals are often distracted by the secondary task when circumventing an obstacle. An increased cognitive load can require prolonged gaze fixation time on a location of interest to compensate for longer information processing duration.Research Question: To investigate the effects of cognitive dual tasking (DT) on gaze behavior during waking with obstacle circumvention in people with PD and control group, and to determine the impact of gaze behavior on motor strategy.Methods: Fifteen individuals with PD (PD-group) and 15 neurologically healthy individuals walked at a self-selected speed over a walkway and circumvented an obstacle centered in the walkway. The experimental conditions (5 trials each one) included obstacle circumvention without DT (OC) and obstacle circumvention with DT (OCDT). In the cognitive task, the participant mentally counted the number of times a target number appeared in an audio recording. We analyzed gaze behavior (i.e. number of gaze fixations and duration on the ground and obstacle), standard gait measures and DT cost. Two-way ANOVAs were completed for gait parameters and moment of fixation.Results: There was no significant difference in DT cost between groups and no obstacle contacts. The participants performed a longer mean duration of fixations on the ground during OCDT compared to OC. Group x condition interactions indicated that the PD-group delayed the obstacle fixation relative to the NHI for OCDT (p < 0.001) and presented greater medial-lateral body clearance (p < 0.001) and longer double support time (p < 0.001) during OCDT compared to OC.Significance: The results of this study suggest that deficits in locomotion during DT in PD-group may be caused, at least in part, by a reduced ability to fixate gaze at appropriate times during walking. [ABSTRACT FROM AUTHOR]

• We tested the effects of horizontal and vertical saccades on postural stabilization. • Semi tandem stance was used to challenge postural stability during visual tasks. • Saccadic task increased mean velocity of head displacement during semi tandem stance. • There were no CoP adjustments due to saccadic tasks. • Older adults showed variable gaze behavior while standing in semi tandem stance. Differences in the postural stabilization of older and young adults have been shown to be task-dependent on both visual and postural challenges; however, the gaze behavior during such tasks has rarely been examined. This study investigated the effects of horizontal and vertical saccades on gaze control, center of pressure (CoP) and head displacement of young and older adults on different bases of support. Ten young adults (20.7 ± 3.4 years) and ten older adults (71.6 ± 3.1 years) remained in an upright stance on a force platform wearing an eye-head tracker device. The participants performed 30-second trials according to two bases of support (feet apart and semi-tandem) and three gaze behavior (fixation, horizontal and vertical saccades) conditions. Older adults presented greater CoP amplitude (p < 0.002) and velocity (p < 0.001) (ML axis), and higher head amplitude (ML) (p < 0.002) than young adults during the semi tandem base. Head displacement of both groups presented higher velocity (ML axis) during horizontal (p < 0.001) and vertical saccades (p < 0.01) than the fixation task only on the semi tandem base. There was higher number of fixations (p < 0.001) and lower mean fixation duration (p < 0.001) on the semi-tandem base (p < 0.05). The results showed higher gaze latency variability in vertical saccades for older adults (p < 0.01). Challenging postural tasks may alter postural adjustments and gaze control during saccadic tasks. Particularly, the greater postural instability of older adults increased the gaze latency variability during saccadic tasks, suggesting some deterioration in the posture-gaze relation with aging. [ABSTRACT FROM AUTHOR]

This study tested whether adverse effects of state anxiety on attention and performance may be modulated by experience. Sixteen experienced and eleven inexperienced drivers drove in a simulator under low- and high-stress conditions. Anxiety was manipulated by competition, the presence of an evaluator, external video camera, and traffic noise. Most drivers showed greater anxiety scores and higher mean heart rates following manipulation. In both groups increased state anxiety decreased car speed control and caused more collisions, accompanied by fewer fixations of longer duration towards the driving lane across a horizontally narrower region. Inexperienced drivers increased the number of short fixations towards cars, while experienced drivers increased the number of short fixations on the speedometer. Although anxiety impairs processing efficiency and performance effectiveness for both groups, attentional changes differ as a function of experience. Inexperienced drivers tended to shift attention to threatening stimuli, while experienced drives were more likely to consciously monitor task goal. [ABSTRACT FROM AUTHOR]

Background The mechanisms that contribute to gait asymmetry in people with Parkinson’s disease (PD) are unclear, mainly during gait with greater environmental demand, such as when an obstacle is circumvented while walking. Objective The aim of this study was to investigate the effects of obstacle circumvention of the least and most affected side on motor and gaze behavior in people with PD under/without the effects of dopaminergic medication. Methods Fifteen people with PD and 15 matched-control individuals were instructed to walk along a pathway, at a self-selected velocity, and to circumvent an obstacle, avoiding contact with it. Each participant performed five trials for each side. Kinematic parameters, mediolateral and horizontal body clearance to the obstacle, strategy to circumvent the obstacle, and gaze behavior were calculated. Parameters were grouped according to the side that the obstacle was circumvented and compared by three-way ANOVAs. Results Both people with PD and the control group presented asymmetry to circumvent an obstacle during walking, however this was exacerbated in people with PD. Individuals with PD presented safe strategies (largest mediolateral and horizontal body clearance to the obstacle, “lead-out” strategy, and higher number and time of fixations on the obstacle) during obstacle circumvention for the least affected side compared to the most affected side. In addition, positive effects of dopaminergic medication on body clearance, spatial-temporal parameters, and gaze behavior were evidenced only when the obstacle was circumvented to the least affected side. Conclusions The obstacle circumvention to the most affected side is risky for people with PD. [ABSTRACT FROM AUTHOR]

Abstract: Background: The aim of this study was to investigate the effects of chronic treatment with carvedilol in blood pressure (BPV) and heart rate (HRV) variability of rats with myocardial infarction (MI). Methods: MI was produced in male rats by ligature of anterior interventricular branch of left coronary artery. Control rats were submitted to a sham surgery (SO). MI and SO rats were randomized to receive for 30days placebo (Plac 0.5% metilcelulose) or carvedilol (Carv, 2mg/Kg body weight/day, drinking water): SO-Plac (N =10), SO-Carv (N =10), MI-Plac (N =12), MI-Carv (N =13). Blood pressure (BP) was directly recorded in the awake animals and BPV was determined, in time (variance, mmhg2) and frequency domains by the autoregressive method. Statistical significance was set in P <0.05. Data are median and interquartile range. Results: No significant changes in HRV was observed in MI rats, while BPV showed significant decreasing of blood pressure variance (SO-Plac=42.08 (39.21) mmHg2 vs. MI-Plac=21.67 (12.58) mmHg2, P <0.05), reversed by the Carv treatment (MI-Plac=21.67 (12.58) vs. MI-Carv=38.64 (29.25), P <0.05). In the frequency domain analyses, MI reduced absolute and normalized LF component (LF (mmHg2): SO-Plac=8.98 (14.84) vs. MI-Plac=2.08 (4.84), P <0.05; LF(nu): SO-Plac=79.48 (45.03) nu vs. MI-Plac=24.25 (40.67) nu, P <0.05) and increased the normalized HF component of the BPV (SO-Plac=20.51 (39.18) vs. MI-Plac=60.51 (39.73). Carv treatment significantly attenuated the LF component fall. Conclusion: Chronic treatment with carvedilol restored the variance of BPV altered by the MI. [Copyright &y& Elsevier]

Highlights: [•] Aged spontaneously hypertensive underwent a chronic salt intake. [•] Coronary artery relaxation is compromised in spontaneously hypertensive rats. [•] High salt intake in aged SHR does not impair the coronary artery relaxation. [•] RAAS system does not add additional impairment in coronary relaxation of SHRs. [ABSTRACT FROM AUTHOR]

Abstract: High dependence on pollination is considered the main cause of low productivity in American yellow passion fruit crops (Passiflora edulis f. flavicarpa). As intensive farming practices require similarly intensive manual pollination, this study sought answer the following questions: (a) is there a difference in the efficiency of fruit production when one or more stigmas are pollinated manually, by natural pollinators (or both)? and (b) does manual or natural pollination (or both) affect the physical and chemical characteristics of the fruits? Flowers were pollinated manually, naturally by native bees or by using both methods. Fruit production was evaluated seven days after anthesis, as well as some selected physico-chemical characteristics of harvested fruits. It was demonstrated that the pollination of yellow passion fruit is satisfactory only with visitation by native bees, especially carpenter bees. There is no difference in fruit production efficiency when one or more stigmas are pollinated manually and then left free for visits by natural pollinators. Manual pollination in one stigma produced less seeds and lower biomass of fruit juice of yellow passion fruits. When there is the presence of natural pollinators (notably carpenter bees), manual services can be reduced but not completely dismissed. Therefore, yellow passion fruit farmers can potentially reduce production costs. [Copyright &y& Elsevier]

Abstract: This work assessed the influence of the autoregressive model order (ARMO) on the spectral analysis of the heart rate variability (HRV). A sample of 68 R–R series obtained from digital ECG records of young healthy adults in the supine position was used. Normalized spectral indexes for each ARMO were compared by Friedman test followed by the Dunn''s procedure and statistical significance was set at P<0.05. The results showed that the AR method using orders from 9 to 25 produces normalized spectral parameters statistically similar and, hence, the algorithms commonly employed to estimate optimum order are not mandatory in this case. [Copyright &y& Elsevier]

Davis Bank is one of the biggest cone-like seamounts in the Vitória-Trindade Ridge (VTR) offshore Eastern Brazil. This volcanic structure is mostly constituted by peralkaline Eocene basanitic lavas (MgO ca. 4.0 wt%). The lithology comprises an inequigranular aphanitic rock composed of lath-like minerals scattered all over the matrix, containing microphenocrysts of plagioclase, clinopyroxene, and opaque minerals, immersed in a matrix displaying pseudo-trachytic and micro glomeroporphyritic textures. Regarding mineral chemistry, the plagioclase (labradorite to bytownite) and clinopyroxene (diopside to diopside salite) crystals were analyzed to obtain their chemical composition and retrieve the P-T crystallization conditions. The determination of these thermodynamic conditions was based on plagioclase-liquid and clinopyroxene-liquid thermobarometers. This analysis yielded crystallization conditions ranging from 4 to 9.9 kbar and from 1050 to 1173 °C, indicating crystallization in a magma chamber located at 12–30 km depth. Although the VTR seamounts have a common origin related to the Trindade plume, the integration of the petrological data with the geophysical and tectonic interpretations allowed the distinction between the Davis Bank from the other seamounts in the ridge. The radiometric age determinations suggest the voluminous tephritic (basanitic) magmatism in Davis Bank was synchronous with important tectono-magmatic events in the South American plate. • Thermodynamics conditions based on petrography and mineral chemistry. • Volcanogenic processes related to magmatic evolution. • Magmatic chamber depths and comparison with VTR. • Integrating geobarometric with geophysical data. [ABSTRACT FROM AUTHOR]

The oceanic basins are dotted by seamounts, guyots and islands formed by the mantle plumes and oceanic lithosphere interaction. These plumes are responsible for several intraplate volcanisms such as the Emperor-Hawaii Chain in the Pacific Ocean with a remarkable bend at ca. 47 Ma. Comparatively, the Vitória-Trindade Ridge (VTR) in the South Atlantic Ocean was also generated by a mantle plume and in response to the lithosphere interaction and tectonic settings it shows three remarkable bends through time. One occurred after 85 Ma associated with the Trindade plume tail movement under the Archean São Francisco Craton, and another one ca. 52 Ma after the formation of the Abrolhos Bank in the Brazilian platform (Mohriak, 1989; Thompson et al., 1998) when the Trindade Plume encountered a thinner lithosphere in the Brazilian coast and formed a chain of seamounts and islands of W-E direction. The last bend marked in the Trindade plume trajectory is ca. 20°00′lat, around Davis Bank, marking a Miocene (21.07 Ma - 40Ar/39Ar whole-rock method) subtle clockwise rotation in the South American Plate. The easternmost part of this ridge is composed of Trindade-Martin Vaz Archipelago subject of this study. Located ca. 1200 km away from the Brazilian coastline at the Vitória (ES) parallel, its geology is an important preserved record of an alkaline Pliocene-Pleistocene volcanism, the youngest one recorded in the Brazilian territory. Martin Vaz and the nearby islets are located on the easternmost part of the VTR. Its geological features include phono-tephritic to tephri-phonolitic domes; nosean-phonolitic dykes and sub-horizontal layers formed by pyroclastic rocks and subordinate lava flows (melanephelinites) of Volcanian-style magmatism (mostly). 40Ar/39Ar ages yielded values ranging from 336 to 721 ka representing a young and short period of intraplate magmatic activity in the South American Plate offshore. These new ages associated with compiled radioisotopic ages from onshore and offshore volcanic rocks represent a strong decreasing age correlation related to Trindade Mantle Plume. Moreover, Trindade-Martin Vaz Archipelago is a contemporaneous product of a terminal plume expression in the offshore portion of a long-lived track (ca. 90 Ma) with a slow shear velocity (V S) placing its origin at the Upper Mantle suggesting a shallow mantle plume rising from the asthenosphere. • We dated samples from Martin Vaz Island, South Atlantic, by 40Ar/39Ar method revealing the youngest magmatism in the Brazilian territory; • We proposed that this island is part of the mantle plume track named Trindade Plume; • Additional data from literature corroborated with the plume track model from continental to oceanic crust rock samples dated by K–Ar and 40Ar/39Ar methods; • Plio-Pleistocene alkaline magmatism emphasized the recent activity of the Trindade Plume; [ABSTRACT FROM AUTHOR]

Bioenergy can contribute to low-carbon economy of Latin-America and African countries, where the biomass is a viable alternative to obtain a global energy matrix. The harvesting forest residue left on the ground of industrial tree plantations appears an option to be a biomass source to supply a combined heat and power plant. The goals of this study were to know the biomass production and the fuel quality of stumps and coarse roots from a commercial-scale harvesting operation of Eucalyptus under coppice regime in Brazil. To accomplish this objective, the stumps of two Eucalyptus commercial clones were evaluated entirely. Forest inventory data were combined with sampling procedures of the stump (which was removed with a front wheel loader) to obtain the biomass production. The physical and the chemical composition of stumps and roots were determined at the laboratory according to ASTM standards. Guiding values for concentrations of combustion-relevant elements in solid biofuels were introduced. The results showed that stump and its properties were statistically affected by variation factors (clone and rotation). The properties qualified the use of eucalypt stump and coarse roots biomass for energy purposes and suggested a minor unwanted component formed during the burning. Stump biomass production was at least 36 Mg ha−1 after six years of planting, totaling an energy yield of 626 GJ ha−1. Although the results found were suitable for the bioenergy scenario, the environmental sustainability of stump harvesting on forestry site must be studied carefully before its indiscriminate use. • Biomass production of eucalypt stump harvesting. • The physical and chemical properties of stump and coarse root were studied. • Clone (specie) and rotation were statistically significative on biomass and energy yield. • An environmental balance in the forestry site should be studied before its indiscriminate commercial use. [ABSTRACT FROM AUTHOR]

• Standing task was done wearing and not the VR goggles with eyes-opened and closed. • Wearing the VR head-mounted goggles increase body sway during standing. • Discrepancy in sensory integration and goggles physical weight explains higher sway. • Wearing the VR head-mounted goggles with eyes-closed did not change body sway. • VR head-mounted goggles optics did not change body sway during standing. The aim of this study was to investigate the effects of wearing virtual reality head-mounted goggles (VR) on body sway in young adults. We run two experiments, in which we compared the body sway while standing during the conditions of 1) wearing and non-wearing VR with eyes-opened (experiment #1), 2) wearing and no-wearing VR with eyes-closed (experiment #2), and 3) wearing VR with eyes-opened when the scene was turned on and off (experiment #2). Forty-four (experiment #1) and fifteen (experiment #2) young adults were instructed to remain as still as possible on a force plate for 60-s and performed three trials in each quiet standing condition. The center of pressure (CoP) displacement, mean velocity, root mean square (RMS), area and median frequency of sway were calculated in both experiments. In the experiment #1, wearing VR condition with eyes-opened largely increased the AP and ML CoP displacement, AP mean velocity, AP and ML RMS, and area (p < 0.05) compared to non-wearing VR with eyes-opened. In the experiment #2, no differences were found for any conditions (eyes-closed and eyes-opened with turned on and off VR scene). In conclusion, wearing VR head-mounted goggles increased body sway of young adults during standing postural task, when the individuals were with eyes-opened. However, the effects of wearing VR head-mounted goggles on body sway disappeared when the individuals were with eyes-closed or the google scene was turned off the scene compared to not wearing VR head-mounted goggles with eyes-closed or turned on scene, respectively. [ABSTRACT FROM AUTHOR]