70 research outputs found
desafios e avanços para os paÃses
Dissertação com vista à obtenção do grau de Mestre em Direito e GestãoO cenário contemporâneo oferece a oportunidade de pensar a relação da tecnologia e as
constantes mudanças que afetam a sociedade. Assim, no que diz respeito especificamente à s
tratativas entre o contribuinte e o Fisco, vê-se que as inovações tecnológicas estão
promovendo um profundo impacto na administração dos sistemas fiscais, e tem
revolucionado a forma como as administrações fiscais coletam as informações necessárias
para protegerem sua base tributária, a fim de reduzirem os encargos administrativos e
gerenciarem de forma profÃcua a conformidade de seus contribuintes. Assim, este trabalho, a
partir da leitura crÃtica da Série Administração Fiscal de 2019 da Organização para a
Cooperação e Desenvolvimento Econômico – OCDE, teve como finalidade compreender
como algumas das administrações fiscais dos paÃses da Série mencionada tem se utilizado de
tecnologias digitais para aumentarem seus nÃveis de cumprimento fiscal e quais os seus
desafios e limites do uso desses meios tecnológicos em relação a essa matéria. Argumenta-se,
portanto, que em que pese a importância do uso de tecnologias digitais como forma de
alavancar o Compliance Fiscal, com base no referida Série da OCDE – o que seria positivo
tanto para as administrações fazendárias, bem como para os paÃses – vê-se que ainda pairam
desafios sobre o uso de tecnologias digitais como forma de alavancar o Compliance, uma vez
que os paÃses têm capacidades tecnológicas diferentes, reguladores e partes interessadas que
se comportam de maneiras distintas e por vezes ocorre um descompasso entre a rapidez das
mudanças tecnológicas e a inflexibilidade do direito fiscal perante essas mudanças.The contemporary scenario offers the opportunity to think about the relationship between
technology and the constant changes that affect society. Thus, specifically with regard to the
treaties between the taxpayer and the tax authorities, it can be seen that technological
innovations are having a profound impact on the tax administration systems, and have
revolutionized the way that tax administrations collect the necessary information to protect
their tax base, in order to reduce administrative burdens and manage the compliance of their
taxpayers in a profitable way. Thus, this work, based on a critical reading of the 2019 Tax
Administration Series of the Organization for Economic Cooperation and Development -
OECD, aimed to understand how some of tax administrations in the aforementioned Serie
have used digital technologies to increase their levels of tax compliance and what are their
challenges and limits to the use of these technological means in relation to this matter. It is
argued, therefore, that in spite of the importance to the use of digital technologies as a way of
leveraging fiscal compliance, based on the OECD Serie - which would be positive for both
the tax administrations and the countries - there are still challenges on the use of digital
technologies as a way of leveraging compliance, since countries have different technological
capacities, regulators and stakeholders that behave in different ways and sometimes there is a
mismatch between the speed of technological change and the inflexibility of tax law in face
of these changes
Nonsmooth pitchfork bifurcation in a dc-dc converter: coexisting attractors and intermittency
In this paper we deal with the analysis of nonlinear dynamical behavior of a single inductor two inputs two outputs (SITITO) power electronics DC-DC converter. The
system can be used to regulate generally two outputs (one positive and one negative). Under certain operating conditions, the switching model can be approximated by a
one dimensional piecewise constant vector field and, as a consequence, the corresponding map is piecewise linear
(PWL). This model is derived and then it is used to study a nonsmooth pitchfork bifurcation in the system. Coexistence
of attractors are detected by using the same model. Intermittent chaotic behavior is also addressed. Analytical results are confirmed by one dimensional and twodimensional
bifurcation diagrams.Peer ReviewedPostprint (published version
Dynamical analysis of an interleaved single inductor TITO switching regulator
We study the dynamical behavior of a single inductor two inputs two outputs (SITITO) power electronics DC-DC converter under a current mode control in a PWM interleaved scheme. This system is able to regulate two, generally one positive and one negative, voltages (outputs). The regulation of the outputs is carried out by the modulation of two time intervals within a switching cycle. The value of the regulated voltages is related to both duty cycles (inputs). The stability of the whole nonlinear system is therefore studied without any decoupling. Under certain operating conditions, the dynamical behavior of the system can be modeled by a piecewise linear (PWL)map, which is used to investigate the stability in the parameter space and to detect possible
subharmonic oscillations and chaotic behavior. These results are confirmed by numerical one dimensional and two-dimensional bifurcation diagrams and some experimental measurements from a laboratory prototype.Peer ReviewedPostprint (published version
Previous spatial learning is required for the development of place preference in rats following chronic administration of and withdrawal from morphine
The positive reinforcing properties of addictive drugs have a primary role in the development of drug dependence. In the field of opiates, great attention has been given to this phenomenon, as well as to the negative properties eliciting craving and inducing relapse during withdrawal. This study was designed to evaluate whether elevated plus-maze (EPM) experienced rats withdrawn from low doses of subcutaneous (s.c.) morphine (10 mg/kg), in which a high anxiety level is the most prominent withdrawal symptom, acquire place preference when submitted to a conflict paradigm in which drug effects are paired with an aversive context: the distal part of the open arms of an EPM. Both the anxiety test and place preference conditioning were measured in the same apparatus, a biased version of the plus-maze. In order to verify the influence of previous EPM spatial learning on the performance of morphine-withdrawn rats, half the animals in this study experienced the EPM prior to treatment. Additional groups were also tested under the influence of morphine effects. The effects of the treatments were quantified through the analysis of three types of measures: anxiety was inferred from the use of the conventional measures (percentage of entries and time spent in the open-arms) and risk-assessment behaviours (frequency of stretched-attending postures - SAP, and time spent at the centre of the maze). Place preference conditioning was evaluated through analysis of the number of entries, total time spent and distance run in the open-arm extremities, which is where the animals were conditioned. The number of closed-arm entries was taken as an index of locomotor activity. Our results showed that (i) EPM naïve rats pre-treated with morphine did not develop place preference, behaving like control rats; (ii) rats that had previous experience in the EPM showed no changes in open-arm avoidance on the second exposure, when compared with rats naïve for this condition; (iii) previous spatial learning of the EPM contextual cues was, in fact, a requirement for anxiety-inducing place preference for the open-arms in morphine-withdrawn rats and, (iiii) conditioned place preference was achieved both in rats under the effects of morphine and in withdrawal, probably through the influence of the positive or negative reinforcing effects promoted by the presence or absence of the drug in the central nervous system.FAPES
Dynamics and stability issues of a single-inductor dual-switching DC-DC converter
A single-inductor two-input two-output power electronic dc–dc converter can be used to regulate two generally nonsymmetric
positive and negative outputs by means of a pulsewidth modulation with a double voltage feedback. This paper studies the dynamic behavior of this system. First, the operation modes and the steady-state properties of the converter are addressed, and, then, a stability analysis that includes both the power stage and
control parameters is carried out. Different bifurcations are determined from the averaged model and from the discrete-time model.
The Routh–Hurwitz criterion is used to obtain the stability regions of the averaged (slow-scale) dynamics in the design parameter
space, and a discrete-time approach is used to obtain more accurate results and to detect possible (fast-scale) subharmonic oscillations.
Experimental measurements were taken from a system prototype to confirm the analytical results and numerical simulations.
Some possible nonsmooth bifurcations due to the change in the switching patterns are also illustrated.Postprint (published version
La prevalencia del dolor crónico en estudiantes de EnfermerÃa
A dor crônica é uma das principais causas de incapacidade entre os indivÃduos. O objetivo do estudo foi estimar a prevalência deste tipo de dor em estudantes universitários de Enfermagem e caracterizá-la segundo a ocorrência, localização, duração, intensidade e qualidade. Estudo transversal, desenvolvido em uma Faculdade de Enfermagem de Goiás, entre maio e junho de 2008, com 211 estudantes. A prevalência de dor crônica autorrelatada foi de 59,7%, frequentemente localizada na cabeça (38,1%), região lombar (11,9%) e ombros/ membros superiores (11,9%). Em 46% dos casos, o convÃvio com a dor variou de um a cinco anos; a intensidade foi caracterizada como forte (Mediana do escore de dor=7,0) e descrita como latejante, pontada, cansativa, enjoada, que incomoda e aperto. A alta prevalência de dor entre jovens universitários de enfermagem aponta o futuro da saúde dessa população, a necessidade de intervenções para redução de agravos e adequado alÃvio dessa experiência.Chronic pain is one of the major causes of disability among individuals. This study aims to estimate the prevalence of this type of self-reported pain by undergraduate Nursing students and characterize it concerning its occurrence, location, duration, intensity, and quality. This cross-sectional study was developed at a Nursing College in Goiás, Brazil, between May and June of 2008 with 211 students. The prevalence of self-reported chronic pain was 59.7%, frequently located in the head (38.1%), lower back (11.9%) and shoulder/upper members (11.9%). In 46% of the cases, living with the pain ranged from one to five years with a strong intensity (Median pain scores=7) and was described as throbbing, stabbing, tiring, sickening, that bothers, and tight. The prevalence of pain is higher than that estimated in similar studies, pointing to the future health of this generation and the need for disease prevention and health promotion programs for adequate relief among this population.El dolor crónico es una de las principales causas de discapacidad entre las personas. Los objetivos de este estudio: estimar la prevalencia este tipo de dolor en los estudiantes universitarios de EnfermerÃa, caracterizar el dolor según la aparición, localización, duración, intensidad y calidad. Se trata de un estudio transversal desarrollado en un Facultad de EnfermerÃa de Goiás, de mayo a junio de 2008, con 211 estudiantes. La prevalencia del dolor crónico informado fue del 59,7%, localizado a menudo en la cabeza (38,1%), en la región lumbar (11,9%) y en el hombro/extremidades superiores (11,9%). En el 46% de los casos, la convivencia con el dolor varió de uno a cinco años, la intensidad se caracterizó por ser muy fuerte (puntación de dolor media=7,0) y se describe como palpitante, agudo, agotador, repugnante, y que incomoda y aprieta. La alta prevalencia de dolor entre los estudiantes de enfermerÃa indica la salud futura de esta población, la necesidad de intervenciones para reducir las lesiones y el alivio adecuado de esta experiencia
Carcass characteristics and fatty acid profile of Santa Inês lamb fed banana leftovers
The use of new feed resources, particularly local agroindustrial byproducts, such as banana, may be an option for replacing those traditionally used for sheep feed to reduce production costs. Thus, the aim of this study was to evaluate the dietary effects of replacing corn bran with banana leftovers on performance, carcass, non-carcass components, meat traits, and fatty acid profile of Santa Inês lambs. Twenty-four Santa Inês female lambs with an average weight of 23.73 kg were fed diets containing 60 % coast cross hay and 40 % concentrate (30 % corn bran and 10 % soybean meal). Treatments consisted of corn bran replaced by banana leftovers at rates of 0, 25, 50, and 75 % on a dry matter basis. The experiment lasted 120 days. Animals were slaughtered and carcasses and non-carcass components were evaluated. The half-carcasses were weighed and sectioned into commercial cuts. The 12th and 13th ribs were dissected to collect bones, muscle and fat proportions. Cooking loss, color, shear force and sarcomere length were measured. Fatty acid profiles were obtained by gas chromatography. Hot and cold carcass weight, leg, neck, lung, loin eye area, fat thickness, initial sample weight of the 12th and 13th ribs, fat and bone, presented a negative linear effect of banana leftovers replacing corn in the diet. Loin, fat thickness, cooking loss and carcass redness showed a negative quadratic effect, while full and empty abomasum, full omasum, sarcomere length and yellowness presented a positive quadratic effect. Replacement of up to 75 % of corn bran by banana leftovers did not interfere in the intake, performance, meat traits and the fatty acid profile of lambs. The use of banana leftovers may be an alternative for reducing animal production costs
Carcass characteristics and fatty acid profile of Santa Inês lamb fed banana leftovers
The use of new feed resources, particularly local agroindustrial byproducts, such as banana, may be an option for replacing those traditionally used for sheep feed to reduce production costs. Thus, the aim of this study was to evaluate the dietary effects of replacing corn bran with banana leftovers on performance, carcass, non-carcass components, meat traits, and fatty acid profile of Santa Inês lambs. Twenty-four Santa Inês female lambs with an average weight of 23.73 kg were fed diets containing 60 % coast cross hay and 40 % concentrate (30 % corn bran and 10 % soybean meal). Treatments consisted of corn bran replaced by banana leftovers at rates of 0, 25, 50, and 75 % on a dry matter basis. The experiment lasted 120 days. Animals were slaughtered and carcasses and non-carcass components were evaluated. The half-carcasses were weighed and sectioned into commercial cuts. The 12th and 13th ribs were dissected to collect bones, muscle and fat proportions. Cooking loss, color, shear force and sarcomere length were measured. Fatty acid profiles were obtained by gas chromatography. Hot and cold carcass weight, leg, neck, lung, loin eye area, fat thickness, initial sample weight of the 12th and 13th ribs, fat and bone, presented a negative linear effect of banana leftovers replacing corn in the diet. Loin, fat thickness, cooking loss and carcass redness showed a negative quadratic effect, while full and empty abomasum, full omasum, sarcomere length and yellowness presented a positive quadratic effect. Replacement of up to 75 % of corn bran by banana leftovers did not interfere in the intake, performance, meat traits and the fatty acid profile of lambs. The use of banana leftovers may be an alternative for reducing animal production costs
Allergies and Diabetes as Risk Factors for Dengue Hemorrhagic Fever: Results of a Case Control Study
Dengue is an arboviral disease that affects large areas of countries in tropical and subtropical regions of the world. Around 500,000 cases and 22,000 deaths of dengue hemorrhagic fever (DHF)/Dengue Shock Syndrome (DSS), the most severe presentations of this disease, occur annually. It is unclear why some cases of dengue fever (0.5% to 4%) progress to DHF/DSS. There is weak evidence that some diseases could have a role in this process, such as diabetes, hypertension, and allergies. In epidemics most dengue fever cases are sent home as there are too many to be kept in observation, but if it were possible to identify those with a higher risk of progression to DHF, they could be kept for observation, for early detection of signs, symptoms and alterations in laboratory tests suggestive of DHF, to enable timely and effective clinical management and early intervention. We study this issue and we believe that the evidence produced in this study, when confirmed in other studies, suggests that screening criteria might be used to identify adult patients at a greater risk of developing DHF with a recommendation that they remain under observation and monitoring in a hospital
- …