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Exponential stabilization to time-dependent trajectories for the incompressible Navier–Stokes equations is achieved with explicit feedback controls. The fluid is contained in a given two-dimensional spatial domain. An appropriate finite number of actuators is constructed and the control force is, at each time instant, a linear combination of such actuators. Each actuator has its vorticity supported in a small subdomain. The velocity field is subject to Lions boundary conditions. Simulations are presented showing the stabilizing performance of the proposed feedback. The results also apply to a class of observer design problems. [ABSTRACT FROM AUTHOR]

Stabilizing feedback operators are presented which depend only on the orthogonal projection of the state onto the finite-dimensional control space. A class of monotone feedback operators mapping the finite-dimensional control space into itself is considered. The special case of the scaled identity operator is included. Conditions are given on the set of actuators and on the magnitude of the monotonicity, which guarantee the semiglobal stabilizing property of the feedback for a class of semilinear parabolic-like equations. Subsequently an optimal feedback control minimizing the quadratic energy cost is computed by a deep neural network, exploiting the fact that the feedback depends only on a finite dimensional component of the state. Numerical simulations demonstrate the stabilizing performance of explicitly scaled orthogonal projection feedbacks, and of deep neural network feedbacks. [ABSTRACT FROM AUTHOR]

The estimation of the full state of a nonautonomous semilinear parabolic equation is achieved by a Luenberger-type dynamical observer. The estimation is derived from an output given by a finite number of average measurements of the state on small regions. The state estimate given by the observer converges exponentially to the real state, as time increases. The result is semiglobal in the sense that the error dynamics can be made stable for an arbitrary given initial condition, provided a large enough number of measurements, depending on the norm of the initial condition, are taken. The output injection operator is explicit and involves a suitable oblique projection. The results of numerical simulations are presented showing the exponential stability of the error dynamics. [ABSTRACT FROM AUTHOR]

A Luenberger type dynamical observer is proposed for estimation of the full state of a nonautonomous linear parabolic equation, from a finite-dimensional output. The output is given by average-like measurements of the state on small regions. The state estimate given by the observer converges exponentially to the real state, as time increases. The operator which injects the output into the dynamics of the observer is explicit and involves an appropriate oblique projection. Results of numerical simulations are presented showing the exponential stability of the error dynamics, and thus showing the estimating performance of the observer. [ABSTRACT FROM AUTHOR]

The stabilization of a class of nonlinear weakly damped wave equations by means of a finite-dimensional feedback control is investigated. The stabilizing control is constructed based on an appropriate oblique projection and it enters as a time-dependent linear combination of a finite number of suitable indicator functions supported in small regions. Firstly, it is shown that an oblique projection feedback is able to globally exponentially stabilize linear nonautonomous weakly damped wave equations. Then, relying on this result, the local stabilization for semilinear equations is proven for a suitable class of nonlinearities. Finally, numerical experiments are given which validate the theoretical results. [ABSTRACT FROM AUTHOR]

The genus Cyclocephala is common in Brazil (Coleoptera, Scarabaeidae, Dynastinae). The adults of some species are important pollinators, and the larvae develop in the soil, feed on organic matter, and contribute to nutrient cycle, but immatures of some species feed on plant roots, and some were registered causing damage in crops. The mating process of some phytophagous scarab beetles has a chemical recognition step, and the antenna is the main structure involved in the detection of odorants associated with insect communication. In the present study the mating behavior, life cycle, and antennal sensilla of C. putrida are described. The study was conducted at the Universidade Estadual de Mato Grosso do Sul, Cassilândia, Brazil. Adults were collected by a light trap installed from January 2016 to December 2017 and were taken to the laboratory for studies. Adults swarms are brief and were registered from January to February, and specimens were mostly collected at 20:00 to 22:00h. Chemical recognition may occur at least during one of the mating steps, during which the couple kept their antennae moving and the lamellae open, while females select males. In laboratory, the mating process lasted 7.5 minutes on average. The antennae of females have about 3399 sensilla and males about 4229 sensilla. Sensilla placodea types I, II, and III are the most abundant, and sensilla ampullacea, basiconica, and coeloconica are also present. The embryonic period lasted 16.0 days; first, second and third instars lasted 16.0, 48.3, and 165.3 days, respectively. The pupal period lasted 24.0 days. The period between egg deposition and adult emergency is about 271.5 days. [ABSTRACT FROM AUTHOR]

Diabetic older people tend to present deteriorated performance in balance and locomotion activities, even those without peripheral neuropathy. There is evidence that saccadic eye movements are used to reduce body sway in young and older healthy adults, but it has not been shown that diabetic older people preserve this visuomotor adaptation capacity. Are diabetic older women without peripheral neuropathy capable of improving postural stability during a saccadic gaze task? Seventeen type 2 diabetic older women (68.2 ± 10.7 years old) and seventeen healthy women, age-matched controls (66.0 ± 8.4 years old) voluntarily participated in the study. All participants were instructed to stand upright, barefoot, as stable as possible, for 30 s. Participants maintained their feet parallel to each other, at standard and narrow bases of support, while either fixating on a stationary target (fixation condition) or performing horizontal saccadic eye movements to follow a target (eccentricity of 11° of visual angle), which continuously disappeared and reappeared immediately on the opposite side (saccade 0.5 Hz and saccade 1.1 Hz conditions). Results indicated that the diabetic group clearly had deteriorated postural control, as shown by increased values of mean sway amplitude and mean sway velocity. However, diabetic and control groups were similarly capable of using saccadic eye movements to improve their postural stability, reducing their sway velocity compared to a gaze fixation condition. Diabetes per se (without peripheral neuropathy) amplifies postural sway of older women as compared to their healthy age-matched controls. However, diabetic older women without peripheral neuropathy are capable of improving postural stability during a saccadic gaze task. • Diabetic older women without peripheral neuropathy show amplified body sway. • Diabetes does not affect use of saccadic eye movements to improve postural stability. • Saccadic gaze tasks may support development of oculomotor training for diabetics. [ABSTRACT FROM AUTHOR]

The Liberdade and Andrelândia nappes, SE Brazil, record the western Gondwana amalgamation in the Southern Brasília Orogen during the Ediacaran. The Liberdade Shear Zone acted as the boundary between these two overlapping nappes. Quartz c-axis fabrics and strain data from quartzite samples and petrological data from hosting metapelite rocks were analyzed to investigate the tectonic processes involved in nappe development. Further constraints were achieved by conducting petrological modeling and geothermobarometry using P – T isochemical phase diagram approaches. Quartz axis plots show consistency with different kinematic criteria verified in the field in meso and macroscale. The fabrics are associated to both coaxial deformation and non-coaxial deformation. Quartz microstructures, metamorphic assemblages and c-axis concentrations primarily around Y and X structural directions suggest that deformation was accommodated by grain boundary migration recrystallization under temperature above 500 °C. Disregarding pressure effects the opening angles of quartz c-axis fabrics suggest temperatures between 480 and 640 °C (muscovite quartzite) and 650–720 °C (sillimanite quartzite). Considering pressure data, the opening angles indicate conditions of 550–650 °C and 7–10 kbar (muscovite quartzite) and 600–730 °C and 4–7 kbar (sillimanite quartzite), reflecting primarily distinct baric regimes. Sillimanite-bearing samples estimatives are supported by ubiquitous presence of chessboard subgrain patterns in quartz and by modeled isochemical phase diagrams that constrain conditions of 660–730 °C and 6–7 kbar for garnet-sillimanite-biotite schist samples. Altogether, these results indicate progressive tectonic evolution linked to oblique convergence between tectonic units represented by the Andrelândia and Liberdade nappes and the Paleoproterozoic basement. Besides recording distinct thermal and baric regimes, the nappes also present different structural styles, suggesting that pressure and temperature are important boundary conditions for the nappe structural style. • C-axis and aperture angles differentiate nappes with different histories. • Lateral extrusion explains oblique plunging lines and metamorphic variation. • The Liberdade Shear Zone has a transpressive character. • OA and paragenesis indicate P-T conditions of 500–710 °C and 4–10 kbar. • Thermobarometry and petrological modeling constrain 660–730 °C and 6–7 kbar. [ABSTRACT FROM AUTHOR]

When suitable, adults of Scarabaeidae usually form swarms to find food and breeding sites. The steps of mating behavior can be mediated by chemical communication, and antennal sensilla are released volatiles detection structures, as sexual pheromones. In present work the mating behavior and the antennal sensilla of Anomala inconstans Burmeister, 1844 are described. The study was conducted at the Universidade Estadual de Mato Grosso do Sul, Cassilândia, Brazil from March 2015 to December 2017. Adults were collected through a light trap and taken to the laboratory for studies. Field and laboratory observations provided data for the description of the steps of mating behavior. Adults swarms were registered from September to November 2015 at 05:30 pm to 00:00 am. Females display a calling behavior from 05:25 pm to 08:00 pm, in which they rub their posterior legs against their abdomen, and after a few minutes males are able to locate them. In laboratory, the mating process lasted 20.4 minutes on average, and the possibility of chemical communication between adults was here discussed. The antennae of the species have trichoid, chaetica, placoid types I, II and III, and coeloconic types I and II sensilla. Placoid sensilla are the most abundant and females have more sensilla than males. [ABSTRACT FROM AUTHOR]

The 3D Navier–Stokes system, under Lions boundary conditions, is proven to be approximately controllable provided a suitable saturating set does exist. An explicit saturating set for 3D rectangles is given. [ABSTRACT FROM AUTHOR]

Exposure to reflected glare occurs most often during human interactions with the digital interfaces of devices such as computers, tablets and smartphones, among others. Several ergonomic problems are associated with this condition. In this article we specifically address the effect of glare reflected in digital interfaces on the visual performance of users. This aspect is still little studied quantitatively, although it is widely approached by research, norms and ergonomic recommendations. Participants performed the reading of graphical characters presented on a tablet with areas of the interface with and without obfuscation. The participants' visual performance was analyzed by tracking ocular movements (obtained through an eye tracker) and visual audio records of the experimental condition. The results demonstrate that there was no effect of reflected glare on the discriminatory visual efficiency, however, the time demanded in this process was significantly higher. In this way, the visual strategies adopted in front of the reflected glare in digital interfaces can be effective for the maintenance of the discriminatory efficiency, which happens to the detriment of the temporal efficiency. [ABSTRACT FROM AUTHOR]

The Navier–Stokes system is considered in a compact Riemannian manifold. Gevrey class regularity is proven under Lions boundary conditions: in 2D for the Rectangle, Cylinder, and Hemisphere, and in 3D for the Rectangle. The cases of the 2D Sphere and 2D and 3D Torus are also revisited. [ABSTRACT FROM AUTHOR]

The minimization of energy-like cost functionals is addressed in the context of optimal control problems. For a general class of dynamical systems, with possibly unstable and nonlinear free dynamics, it is shown that a sequence of solutions of finite time-horizon optimal control problems approximates a solution of the analog infinite time-horizon problem. The latter solution and corresponding optimal cost value function are not assumed to be known a-priori. Numerical simulations are presented validating the theoretical findings for several examples, including systems governed by both ordinary and partial differential equations. [ABSTRACT FROM AUTHOR]

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]

Simvastatin (SV) is a common drug, used for reducing LDL-C levels in blood. One of its drawbacks is poor solubility in water. This forces the use of large therapeutic doses, which enhances side effects. Poly(vinyl alcohol) (PVA) hydrogels have most of the desirable properties required as a matrix for dissolution and delivery of SV. The interaction between SV and PVA, in cryogel matrices, that leads to the enhancement of SV solubility was studied. From thermal analysis, it was found that upon increasing the amount of SV incorporated into PVA matrices, the degradation temperature of PVA decreases. This decrease is accompanied by a decrease in the melting temperature and in the corresponding melting enthalpy, as seen by differential scanning calorimetry (DSC), indicating that in the presence of SV, the PVA structure becomes more amorphous. Molecular dynamics (MD) studies show that the structure of PVA in water suffers changes in the presence of SV, such that the hydroxyl groups tend to move away from SV, allowing for a better interaction of the latter with the hydrocarbon chain, whilst hydroxyl groups interact with water molecules, suggesting an amphiphilic behavior of PVA. The interaction between SV and PVA is also confirmed by release kinetics to water-ethanol (1:1 v/v) and water. In conclusion, this brings new promising opportunities for using this polymer as a prolonged-release cryogel matrix suitable both for the entrapment and release of moderately or highly hydrophobic drugs into water. [ABSTRACT FROM AUTHOR]

Larvae, pupae and adults of Gymnetis rufilateris (Illiger, 1800) (Coleoptera: Cetoniidae: Cetoniinae) were collected in the municipality of Rochedo, Mato Grosso do Sul State. Studies on biology and morphology were conducted at the Laboratory of Entomology of the Universidade Estadual de Mato Grosso do Sul in Aquidauana, Mato Grosso do Sul, Brazil. Females of couples formed in the laboratory oviposited and allowed the biology studies. The eggs lasted for 15.5 days. Larvae of the 1st, 2nd and 3rd instars lasted 13.5, 30.6 and 113.1 days, respectively. The pupal period lasted 12.8 days. The egg-to-adult period lasts 186.8 days. The larvae fed on decomposing feces of poultry. In the laboratory, adults fed on ripe banana (Musa sp.) (Musaceae). Descriptions of the 3rd larval instar and pupa of G. rufilateris are presented. A key to known larvae of Gymnetis is also included. [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]

Controllability properties for the Navier-Stokes system are closely related to observability properties for the adjoint Oseen-Stokes system; boundary observability inequalities are derived, for that adjoint system, that will be appropriate to deal with suitable constrained controls, like finitedimensional controls supported in a given subset of the boundary. As an illustration, new boundary controllability results for the Oseen-Stokes system are derived. Finally, some further plausible consequences of the derived inequalities, concerning the Navier-Stokes system, are discussed. [ABSTRACT FROM AUTHOR]

For more than a century, empathy has been a central topic in the study of human emotion. It plays a crucial role in our everyday social life, having implications for the survival of the species. In the case of agents that inhabit virtual worlds and interact socially among each other and with humans, empathy has also been considered to be an important mechanism to promote engaging and believable interactions. However, creating empathic agents, until recently, has been accomplished mostly through the implementation of specific empathic behaviors or by using domain-dependent empirical models. In this article, we propose a generic computational model of empathy that is grounded on recent psychological theories about empathy. The proposed model treats empathy as a process in which the intensity of the empathic response is modulated by a set of factors that involve the relationship between the agents of the empathic interaction, namely, the similarity and affective link, as well as some characteristics of the empathizer agent, such as mood and personality. This model was implemented into an affective agent architecture, which was then used in an evaluation that had 77 participants. The results indicate that our empathy model, when used to simulate a social scenario with a small group of agents, significantly changed the way that the users perceived and described the interactions between those agents. [ABSTRACT FROM AUTHOR]

Martin Vaz Island is one of the oceanic islands of the homonym archipelago linked to the Vitoria-Trindade volcanic seamount ridge, an important South Atlantic physiographic feature. It is located at 20°28′28″S latitude and 28°51′05″W longitude, approximately 1200 km away from the Brazilian coast. Its geology is an important preserved indicator of Pleistocene alkaline volcanic activities. This work presents lithologic mapping and microscopic observations of Martin Vaz Island rocks. The geological map was developed and prepared at the 1:5000 scale using Esri ArcGIS. Some geological features and structures can be highlighted: two necks, several phonolite dykes and sub-horizontal layers formed by phonolitic pyroclastic rocks and basanites. [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: 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]

The beetle, Anomala testaceipennis Blanchard (Coleoptera: Scarabaeidae), occurs in central-western Brazil where larvae feed on the roots of plants causing damage. This research aimed to study sexual dimorphism and mating behavior of A. testaceipennis. Adults of A. testaceipennis were collected with light traps in the experimental area of the State University of Mato Grosso do Sul, in Aquidauana. Laboratory experiments were performed to describe copulation behavior and adult morphology of males and females. In males the last abdominal segment has a pronounced constriction, which is absent in females, and the male’s last segment of the first pair of legs has a ventral projection, which is poorly developed in females. The mating activities of adults begin soon after sunset, when adults leave the soil and fly. When the male encounters a female, he touches her with antennae and tarsi. If accepted, the male climbs on the female and remains on her back, and soon after the copulation begins. When the female does not accept the male for mating, she moves rapidly and can roll on the ground, and by so removing the male. In the field, adults feed and mate on bloomed trees of Oiti, Licania tomentosa Benth (Malpighiales: Chrysobalanaceae) and Louro, Cordia glabrata Martius (Boraginaceae). In trees without inflorescences no adults of this species were found. [ABSTRACT FROM AUTHOR]

In this paper, we consider feedback stabilization for parabolic variational inequalities of obstacle type with time and space depending reaction and convection coefficients and show exponential stabilization to nonstationary trajectories. Based on a Moreau–Yosida approximation, a feedback operator is established using a finite (and uniform in the approximation index) number of actuators leading to exponential decay of given rate of the state variable. Several numerical examples are presented addressing smooth and nonsmooth obstacle functions. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the acute effects of colony-stimulating factor (G-CSF) on ventricular arrhythmias after coronary occlusion in rats. Materials and Methods: Male Wistar rats (10 weeks) received G-CSF (100 μg.kg-1) or vehicle. Thirty minutes later, animals were infarcted by coronary occlusion under artificial respiration. Electrocardiogram was monitored for 30 min to evaluate ventricular arrhythmias. Results: G-CSF treatment reduced the number of premature ventricular beats and the number and duration of ventricular tachycardia. The incidence of ventricular fibrillation was significantly reduced by G-CSF (MI-Cont: 11.2 ± 2.4 vs. MI-GCSF: 5.4 ± 1 events; P < 0.05). However, total duration of ventricular fibrillation was not altered (MI-Cont: 84 ± 16 vs. MI-GCSF: 76 ± 13 sec). Conclusions: Acute administration of G-CSF before coronary ligature in rats reduces the incidence of ventricular premature beats and ventricular tachycardia, suggesting a possible direct electrophysiological effect of this cytokine independently of its genomic effects. However, the data suggest that G-CSF treatment may affect the spontaneous recovery from ventricular fibrillation. Acute G-CSF administration acts directly on cardiac electrophysiology, different from chronic treatment. [ABSTRACT FROM AUTHOR]

We consider the Navier-Stokes system in a bounded domain with a smooth boundary. Given a sufficiently regular time-dependent global solution, we construct a finite-dimensional feedback control that is supported by a given open set and stabilizes the linearized equation. The proof of this fact is based on a truncated observability inequality, the regularizing property for the linearized equation, and some standard techniques of the optimal control theory. We then show that the control coustructed for the linear problem stabilizes locally also the full Navier-Stokes system. [ABSTRACT FROM AUTHOR]

Dynastinae beetles (Coleoptera: Scarabaeidae) are important due to their role in recycling plant material and promoting nutrient turnover. However, some species are phytophagous and can attack crop plants, thus becoming pests. Here, we provide information on the biology and behavior of the rhinoceros beetle Enema pan (F.) (Oryctini), an abundant species in the area of Cerrado-Pantanal ecotone, Aquidauana, Mato Grosso do Sul, Brazil. Adults were collected with a light trap deployed daily from January 2006 to December 2007 in the experimental farm of the Universidade Estadual de Mato Grosso do Sul (Aquidauana campus). Adults were maintained in plastic containers and observations were made daily. Temporal distribution of adults of E. pan occurred in September and October (2006) and from October to December (2007). Flight started at 1930 hours and ended at 2330 hours. Twenty-four eggs (3.28 mm in length by 2.32 mm in width) with a whitish color were ovipositioned directly in to the soil. Adult longevity averaged 22.0 d in the laboratory conditions. Cephalic horn length, body length, and width of E. pan males are greater than those of females. The weight of adults of both sexes was similar. Cephalic horn length of the males of E. pan was positively correlated with his body size. Mating occurred between 0800 and 1030 hours and lasted on average 18.1 min in the laboratory. Several fights among males and other behaviors involving males and females were observed and are reported. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the learning process of a highly complex ballet skill following demonstrations of point-light and video models. 16 participants divided into point-light and video groups (ns = 8) performed 160 trials of a pirouette, equally distributed in blocks of 20 trials, alternating periods of demonstration and practice, with a retention test a day later. Measures of head and trunk oscillation, coordination disparity from the model, and movement time difference showed similarities between video and point-light groups; ballet experts' evaluations indicated superiority of performance in the video over the point-light group. Results are discussed in terms of the task requirements of dissociation between head and trunk rotations, focusing on the hypothesis of sufficiency and higher relevance of information contained in biological motion models applied to learning of complex motor skills. [ABSTRACT FROM AUTHOR]

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]

Optimal control problems of tracking type for a class of linear systems with uncertain parameters in the dynamics are investigated. An affine tracking feedback control input is obtained by considering the minimization of an energy-like functional depending on a finite ensemble of training/sample parameters. It is computed from the solution of an associated differential Riccati equation. Simulations are presented showing the tracking performance of the computed input for trained as well as untrained parameters. • Optimal control problems of tracking type with uncertain parameters in the dynamics. • Affine feedback control input based on an a priori chosen ensemble of parameters. • Robust tracking performance against parameter variations observed in simulations. [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]

This study examined changes in postural control and gaze performance of faller and non-faller older adults under conditions of visual tasks and optical flow manipulations. Fifteen older non-fallers (69.8 years, ± 3.2) and fifteen older fallers (71.1 years, ± 6.4) stood on a force platform inside a moving room wearing an eye tracker. Four tasks were performed: gaze fixation; predictable saccades; unpredictable saccades; and free-viewing. The stimuli appeared at a frequency of 1.1 Hz during conditions of predictable and unpredictable saccades. Sixteen trials were divided into two blocks. In the first block, the room remained stationary. In the second block, the room oscillated, without the participant's awareness, with a 0.6 cm amplitude and 0.2 Hz frequency. Results showed postural sway attenuation in older fallers during the saccadic tasks compared to gaze fixation and free-viewing tasks, in both stationary and moving room conditions. Both groups showed increased center of pressure (CoP) magnitude during the moving room condition and CoP displacements strongly coupled to the room's movement. The influence of the moving room on the postural sway was reduced during the saccadic tasks for both older groups. Older fallers exhibited higher variability compared to older non-fallers. Gaze behavior differences between groups were dependent on the goals of the visual tasks. Therefore, CoP displacements of older adults are reduced during saccadic tasks regardless of their falling history. However, postural and gaze performance of older fallers suggests increased deterioration of postural and oculomotor control which may be used as a predictor of fall risk. [ABSTRACT FROM AUTHOR]

The parades of the samba schools in Rio de Janeiro, since their appearance in the 1930s, have undergone transformations as a way of surviving changes in society over time. With COVID-19 new challenges were imposed, demanding the reinvention of the carnival ritual and its form of internal communication and with society. With the growth of the spectacle associated with television, the associations intensified the interaction with the public in the virtual environment, especially with lives on YouTube. Based on this perception, the estudo de caso (YIN, 2011) and análise de conteúdo (BARDIN, 2016) are adopted to investigate live broadcasts of the semifinals and final to choose the samba of the Mocidade Independente school for 2022. they observe efforts to maintain traditions, reinforce identity, survival strategies, adapt to cyberspace and professionalization online as a form of resistance. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of ankle and hip muscle fatigue on motor adjustments (experiment 1) and symmetry (experiment 2) of postural control during a quiet standing task. Twenty-three young adults performed a bipedal postural task on separate force platforms, before and after a bilateral ankle and hip muscle fatigue protocol (randomized). Ankle and hip muscles were fatigued separately using a standing calf raise protocol (ankle fatigue) on a step and flexion and extension of the hip (hip fatigue) sitting on a chair, at a controlled movement frequency (0.5Hz), respectively. In both experiments, force, center of pressure, and electromyography parameters were measured. The symmetry index was used in experiment 2 to analyze the postural asymmetry in the parameters. Our main findings showed that muscle fatigue impaired postural stability, regardless of the fatigued muscle region (i.e., ankle or hip). In addition, young adults used an ankle motor strategy (experiment 1) before and after both the ankle and hip muscle fatigue protocols. Moreover, we found increased asymmetry between the lower limbs (experiment 2) during the quiet standing task after muscle fatigue. Thus, we can conclude that the postural motor strategy is not muscle fatigue joint-dependent and a fatigue task increases postural asymmetry, regardless of the fatigued region (hip or ankle). These findings could be applied in sports training and rehabilitation programs with the objective of reducing the fatigue effects on asymmetry and improving balance. [ABSTRACT FROM AUTHOR]

Both internal and boundary feedback exponential stabilization to trajectories for semilinear parabolic equations in a given bounded domain are addressed. The values of the controls are linear combinations of a finite number of actuators which are supported in a small region. A condition on the family of actuators is given which guarantees the local stabilizability of the control system. It is shown that a linearization-based Riccati feedback stabilizing controller can be constructed. The results of numerical simulations are presented and discussed. [ABSTRACT FROM AUTHOR]

Given a nonstationary trajectory of the Navier–Stokes system, a finite-dimensional feedback boundary control stabilizing locally the system to the given trajectory is derived. Moreover the control is supported in a given open subset of the boundary of the domain containing the fluid. In a first step a controller (feedback operator) is derived which stabilizes the linear Oseen–Stokes system “around the given trajectory” to zero; for that a corollary of a suitable truncated boundary observability inequality, the regularizing property for the system, and some standard techniques of the optimal control theory are used. Then it is shown that the same controller also stabilizes, locally, the Navier–Stokes system to the given trajectory. [ABSTRACT FROM AUTHOR]

The color of an obstacle may enable a more detailed view of the environment to facilitate obstacle avoidance. However, people with Parkinson’s disease (PD) present visual contrast and color detection dysfunction, which could affect obstacle avoidance according to obstacle color. Thus, the aim of this study was to investigate the influence of obstacle color on locomotor and gaze behavior during obstacle avoidance in people with PD and neurologically healthy older individuals. Thirteen people with PD and eleven matched-control group individuals, with normal visual acuity (20/20 on the Snellen chart), performed 20 trials (5 trials for each obstacle color condition) of the obstacle avoidance task with the following obstacle colors: white, black, red, and blue. Participants were positioned at the beginning of a walkway with their eyes closed and, after the start command, opened their eyes, started walking at their preferred velocity, and crossed the obstacle. Spatial-temporal parameters and fixations on the obstacle (gaze behavior) were measured using a three-dimensional camera system and mobile eye-tracker, respectively. Our main findings were the absence of significant color interaction on locomotor and gaze behaviors, the absence of significant main effect of color on gaze behavior, and an effect of obstacle color on locomotor behavior, specifically in the placement of the heel from the obstacle after crossing and toe-clearance for both trailing and leading limbs, which indicates that obstacle color can play a role in obstacle avoidance during walking. However, there was no consistent obstacle color that influenced the locomotor behavior. Therefore, the conclusion of this study is that obstacle color seems to affect locomotor behavior, but not gaze behavior, during walking with obstacle avoidance in people with PD and neurologically healthy individuals. However, no particular obstacle color causes a consistent effect on locomotor behavior. [ABSTRACT FROM AUTHOR]

The organic compounds present in phosphate rocks decreases the performance of industrial phosphoric acid plant such as stable foam in the reactor and reduction in filtration rates and P2O5 recoveries. The organic matter content in the Khouribga phosphate from Morocco ranges from 1,500 to 3,000 ppm and the reduction of organic carbon content in the Bayóvar phosphate rock was done by thermal treatment at 450°C in batch fluid bed kiln, where Calcined Bayóvar phosphate rock was produced. Three samples of phosphate rock were evaluated in continuous tests in pilot plant, being Non-Calcined Bayóvar, Calcined Bayóvar and Marrocos. The results indicated that Calcined Bayóvar presented the best performance, Marrocos the intermediate values and the Non-Calcined Bayóvar the worst ones. The P2O5 recoveries were 93.9%, 98.1% and 96.2%, while the filtration rates were 5.9, 10.4, 7.5 t P2O5/dia/m² respectively with Non-Calcined Bayóvar, Calcined Bayóvar and Marrocos. It was necessary to use anti-foam and flocculant additives with Non-Calcined Bayóvar, just anti-foam with Marrocos and no additives at all with the Calcined Bayóvar. The results show that is possible to improve the performance of Bayóvar in the production of phosphoric acid by a thermal treatment at 450°C in order to reduce the amount of organic carbon to the range of 1,500 to 3,000 ppm. [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]

The most of phosphate rocks produced by beneficiation of phosphate ores are largely used in production of phosphoric acid (H3PO4) and phosphate fertilizers, like, Triple SuperPhosphate (TSP) and Single SuperPhosphate (SSP). The Bayóvar phosphate rock contains a high content of total organic carbon, between 6,000 to 12,000ppm, from small particles of apatite (Ca10(PO4)6.X2, X=Cl-,F- ou OH-) pellets, which ones are liberated, in the phosphoric acid production, to acid pulp (mainly H3PO4 and CaSO4.2H2O) after reaction between apatite and sulphuric acid. This increases the viscosity of pulp, decreases the filtration rates, generate stable foam in the reactor and consequently reduce the production rate of Industrial Plant.The objective of this study was to present the results and discuss the effects of a low temperature thermal treatment on the behaviour of a sedimentary phosphate. The thermal treatment was effected in a batch fluidized bed kiln in order to reduce the total organic carbon level to the order of 1,500 to 3,500 ppm, commonly checked in the commercial phosphate rocks from Morocco and Florida. The behaviour of the Bayóvar phosphate in the production of phosphoric acid was evaluated in comparative continuous pilot->plant tests with results from the non-treated and the thermally treated Bayóvar phosphate. [ABSTRACT FROM AUTHOR]

Stabilization to a trajectory for the monodomain equations, a coupled nonlinear PDE-ODE system, is investigated. The results rely on stabilization of linear first-order in time nonautonomous evolution equations combined with stabilizability results for the linearized monodomain equations and a fixed point argument to treat local stabilizability of the nonlinear system. Numerical experiments for feedback stabilization of reentry phenomena are included. [ABSTRACT FROM AUTHOR]

The article describes the use of an Internet toolkit in teaching the fundamental concepts of quantum mechanics. The Internet toolkit, formed by the discrete-variable representation (DVR) Fortran program and the graphical front end, allows chemistry undergraduate students to obtain numerical solutions to the one-dimensional Schrödinger equation as applied to bound-state problems involving realistic potentials. It uses a "black box" Fortran code and a graphical user interface developed in Hypertext Preprocessor and JavaScript programming languages.