941 resultados para Differential calculus in Banach spaces


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The aims were twofold: to examine the gambling habits of emerging adult males in the French-speaking regions of Switzerland and to what extent these habits predict problem gambling within this population. We also evaluated problem gambling rates and provided data concerning variables such as gambling location, level of information about problem gambling and awareness of treatment centers. 606 Swiss male conscripts, aged 18-22 years, completed a self-report questionnaire. This was administered during their army recruitment day in 2012. Problem gambling was assessed through the Problem Gambling Severity Index (PGSI) (Ferris and Wynne 2001). 78.5% of the respondents were lifetime gamblers, 56.1% were past-year gamblers. Four out of ten past-year gamblers played in private spaces and in back rooms. The PGSI indicated that 10.8% of past-year gamblers presented with moderate gambling problems, whilst 1.4% appeared to be problem gamblers. The majority of respondents had never received information about problem gambling. Moreover, they were unaware of the existence of treatment centers for problem gambling in their region. PGSI scores were significantly predicted by the variety of games played. Problem gambling rates among young men appear to be higher than those of the general Swiss population. This confirms that emerging adult males are a particularly vulnerable population with regards to gambling addiction. The implications of this are considered for youth gambling-prevention programs.

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BACKGROUND: Bilateral ptosis is a very interesting clinical challenge for doctors because of the multiple possible localizations of a lesion which can lead to this neurological sign. OBJECTIVES: Through this case report, we aim to determine the difference between an apraxia of lid opening (ALO) with difficulty in initiating the act of lid elevation, in spite of adequate understanding, motor control and cranial nerve pathways, and a bilateral ptosis with a lesion in the oculomotor nucleus or blepharospasm. METHODS: The case report of a 50-year-old patient presenting bilateral ptosis and multiple ischemic lesions in the brainstem and bilateral frontal lobe lesions after the emergency removal of a large frontal tumor. RESULTS: Our patient had an ALO according to the neurological follow-up and showed the ability, after a few weeks, of initiating the act of opening her eyes with her hand. The ophthalmic evaluation confirmed that in her case the ALO was associated with a nuclear lesion of the oculomotor nerve secondary to a midbrain lesion. CONCLUSION: Our case report confirms multiple differential diagnoses in bilateral ptosis and the importance of clinical examination in spite of good neurological imaging.

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This paper analyses the impact of Free Trade Agreements (FTAs) on Middle East and North African Countries (MENA) trade for the period 1994-2010. The analysis distinguishes between industrial and agricultural trade to take into account the different liberalisation schedules. An augmented gravity model is estimated using up-to-date panel data techniques to control for all time-invariant bilateral factors that influence bilateral trade as well as for the so-called multilateral resistance factors. We also control for the endogeneity of the agreements and test for self-selection bias due to the presence of zero trade in our sample. The main findings indicate that North-South-FTAs and South-South- FTAs have a differential impact in terms of increasing trade in MENA countries, with the former being more beneficial in terms of exports for MENA countries, but both showing greater global market integration. We also find that FTAs that include agricultural products, in which MENA countries have a clear comparative advantage, have more favourable effects for these countries than those only including industrial products. JEL code: F10, F15

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The chemical amount values vary in a discrete or continuous form, depending on the approach used to describe the system. In classical sciences, the chemical amount is a property of the macroscopic system and, like any other property of the system, it varies continuously. This is neither inconsistent with the concept of indivisible particles forming the system, nor a mere approximation, but it is a sound concept which enables the use of differential calculus, for instance, in chemical thermodynamics. It is shown that the fundamental laws of chemistry are absolutely compatible to the continuous concept of the chemical amount.

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Due to the increased importance of angular leaf spot of common bean (Phaseolus vulgaris) in Brazil, monitoring the pathogenic variability of its causal agent (Phaeoisariopsis griseola) is the best strategy for a breeding program aimed at developing resistant genotypes. Fifty one isolates of P. griseola collected in five Brazilian States were tested on a set of 12 international differential cultivars in the greenhouse. When inoculated plants showed symptoms but no sporulation was observed, they were transferred to a moist chamber for approximately 20-24 h. After this period of time, if no sporulation was observed, the plants were considered resistant; otherwise, they were considered susceptible. From the fifty-one tested isolates, seven different pathotypes were identified. No Andean pathotypes were identified; consequently, all isolates were classified as Middle American pathotypes. Pathotype 63-31 was the most widespread. Pathotype 63-63 overcame resistance genes present in all differential cultivars and also the resistance gene(s) present in the cultivar AND 277. This fact has important implications for breeding angular leaf spot resistance in beans, and suggests that searching for new resistance genes to angular leaf spot must be pursued.

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The most outstanding conceptual challenge of modern crisis management is the principle of consent. It is not a problem only at the operational level - it challenges the entire decision-making structures of crisis management operations. In post-cold war times and especially in the 21st century, there has been a transition from peacekeeping with limited size and scope towards large and complex peace operations. This shift has presented peace operations with a dilemma. How to balance between maintaining consent for peace operations, whilst being able to use military force to coerce those attempting to wreck peace processes? To address such a dilemma, this research aims to promote understanding, on what can be achieved by military crisis management operations (peace support operations) in the next decade. The research concentrates on the focal research question: Should military components induce consent or rely on the compliance of conflicting parties in crisis management operations of the next decade (2020 – 2030)? The focus is on military – political strategic level considerations, and especially on the time before political decisions to commit to a crisis management operation. This study does not focus on which actor or organisation should intervene. The framework of this thesis derives from the so called ‘peacebuilding space’, the scope of peace operations and spoiler theory. Feasibility of both peace enforcement and peacekeeping in countering future risk conditions are analysed in this framework. This future-orientated qualitative research uses the Delphi-method with a panel of national and international experts. Citation analysis supports identification of relevant reference material, which consists of contemporary literature, the Delphi-questionnaires and interviews. The research process followed three main stages. In the first stage, plausible future scenarios and risk conditions were identified with the Delphi-panel. In the second stage, operating environments for peace support operations were described and consequent hypotheses formulated. In the third stage, these hypotheses were tested on the Delphi-panel. The Delphi-panel is sufficiently wide and diverse to produce plausible yet different insights. The research design utilised specifically military crisis management and peace operations theories. This produced various and relevant normative considerations. Therefore, one may argue that this research; which is based on accepted contemporary theory, hypotheses derived thereof and utilising an expert panel, contributes to the realm of peace support operations. This research finds that some degree of peace enforcement will be feasible and necessary in at least the following risk conditions: failed governance; potential spillover of ethnic, religious, ideological conflict; vulnerability of strategic chokepoints and infrastructures in ungoverned spaces; as well as in territorial and extra-territorial border disputes. In addition, some form of peace enforcement is probably necessary in risk conditions pertaining to: extremism of marginalised groups; potential disputes over previously uninhabited and resource-rich territories; and interstate rivalry. Furthermore, this research finds that peacekeeping measures will be feasible and necessary in at least risk conditions pertaining to: potential spillover of ethnic, religious, ideological conflict; uncontrolled migration; consequences from environmental catastrophes or changes; territorial and extra-territorial border disputes; and potential disputes over previously uninhabited and resource-rich territories. These findings are all subject to both generic and case specific preconditions that must exist for a peace support operation. Some deductions could be derived from the research findings. Although some risk conditions may appear illogical, understanding the underlying logic of a conflict is fundamental to understanding transition in crisis management. Practitioners of crisis management should possess cognizance of such transition. They must understand how transition should occur from threat to safety, from conflict to stability – and so forth. Understanding transition is imperative for managing the dynamic evolution of preconditions, which begins at the outset of a peace support operation. Furthermore, it is pertinent that spoilers are defined from a peace process point of view. If spoilers are defined otherwise, it changes the nature of an operation towards war, where the logic is breaking the will of an enemy - and surrender. In peace support operations, the logic is different: actions towards spoilers are intended to cause transition towards consent - not defeat. Notwithstanding future developments, history continues to provide strategic education. However, the distinction is that the risk conditions occur in novel futures. Hence, lessons learned from the past should be fitted to the case at hand. This research shows compelling evidence that swaying between intervention optimism and pessimism is not substantiated. Both peace enforcement and peacekeeping are sine qua non for successful military crisis management in the next decade.

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The objective of this thesis work is to develop and study the Differential Evolution Algorithm for multi-objective optimization with constraints. Differential Evolution is an evolutionary algorithm that has gained in popularity because of its simplicity and good observed performance. Multi-objective evolutionary algorithms have become popular since they are able to produce a set of compromise solutions during the search process to approximate the Pareto-optimal front. The starting point for this thesis was an idea how Differential Evolution, with simple changes, could be extended for optimization with multiple constraints and objectives. This approach is implemented, experimentally studied, and further developed in the work. Development and study concentrates on the multi-objective optimization aspect. The main outcomes of the work are versions of a method called Generalized Differential Evolution. The versions aim to improve the performance of the method in multi-objective optimization. A diversity preservation technique that is effective and efficient compared to previous diversity preservation techniques is developed. The thesis also studies the influence of control parameters of Differential Evolution in multi-objective optimization. Proposals for initial control parameter value selection are given. Overall, the work contributes to the diversity preservation of solutions in multi-objective optimization.

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The determination of the intersection curve between Bézier Surfaces may be seen as the composition of two separated problems: determining initial points and tracing the intersection curve from these points. The Bézier Surface is represented by a parametric function (polynomial with two variables) that maps a point in the tridimensional space from the bidimensional parametric space. In this article, it is proposed an algorithm to determine the initial points of the intersection curve of Bézier Surfaces, based on the solution of polynomial systems with the Projected Polyhedral Method, followed by a method for tracing the intersection curves (Marching Method with differential equations). In order to allow the use of the Projected Polyhedral Method, the equations of the system must be represented in terms of the Bernstein basis, and towards this goal it is proposed a robust and reliable algorithm to exactly transform a multivariable polynomial in terms of power basis to a polynomial written in terms of Bernstein basis .

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We examined the chromosome set of the aphid species Sitobion avenae, Schizaphis graminum and Methopolophium dirhodum by means of conventional staining and C, NOR, AluI and HaeIII banding methods. These species are considered important pests to several plants of economic interest in Brazil. No variation was observed in the number of chromosomes of S. avenae, whereas there was intraspecific variation in the other two species. Interspecific differences in the response to the banding treatments were observed. Whereas these techniques allowed the identification of several S. graminum chromosome pairs, only the AluI treatment was capable of inducing differential staining in the M. dirhodum chromosomes and no clear patterns emerged when the S. avenae preparations were treated

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We determined if the increased vascular responsiveness to endothelin-1 (ET-1) observed in male, but not in female, DOCA-salt rats is associated with differential vascular mRNA expression of ET-1 and/or ET A/ET B receptors or with functional differences in Ca2+ handling mechanisms by vascular myocytes. Uninephrectomized male and female Wistar rats received DOCA and drinking water containing NaCl/KCl. Control rats received vehicle and tap water. Blood pressure and contractile responses of endothelium-denuded aortic rings to agents which induce Ca2+ influx and/or its release from internal stores were measured using standard procedures. Expression of mRNA for ET-1 and ET A/ET B receptors was evaluated by RT-PCR after isolation of total cell RNA from both aorta and mesenteric arteries. Systolic blood pressure was higher in male than in female DOCA rats. Contractions induced by Bay K8644 (which activates Ca2+ influx through voltage-operated L-type channels), and by caffeine, serotonin or ET-1 in Ca2+-free buffer (which reflect Ca2+ release from internal stores) were significantly increased in aortas from male and female DOCA-salt compared to control aortas. DOCA-salt treatment of male, but not female, rats statistically increased vascular mRNA expression of ET-1 and ET B receptors, but decreased the expression of ET A receptors. Molecular up-regulation of vascular ET B receptors, rather than differential changes in smooth muscle Ca2+ handling mechanisms, seems to account for the increased vascular reactivity to ET-1/ET B receptor agonists and higher blood pressure levels observed in male DOCA-salt rats.

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Pharmacological evidence indicates that the basolateral nucleus of the amygdala (BLA) is involved in the mediation of inhibitory avoidance but not of escape behavior in the elevated T-maze test. These defensive responses have been associated with generalized anxiety disorder (GAD) and panic disorder, respectively. In the present study, we determined whether the BLA plays a differential role in the control of inhibitory avoidance and escape responses in the elevated T-maze. Male Wistar rats (250-280 g, N = 9-10 in each treatment group) were pre-exposed to one of the open arms of the maze for 30 min and 24 h later tested in the model after inactivation of the BLA by a local injection of the GABA A receptor agonist muscimol (8 nmol in 0.2 µL). It has been shown that a prior forced exposure to one of the open arms of the maze, by shortening latencies to withdrawal from the open arm during the test, improves the escape task as a behavioral index of panic. The effects of muscimol in the elevated T-maze were compared to those caused by this GABA agonist in the avoidance reaction generated in the light/dark transition test. This defensive behavior has also been associated with GAD. In the elevated T-maze, intra-BLA injection of muscimol impaired inhibitory avoidance (control: 187.70 ± 14.90 s, muscimol: 37.10 ± 2.63 s), indicating an anxiolytic effect, without interfering with escape performance. The drug also showed an anxiolytic effect in the light/dark transition test as indicated by the increase in the time spent in the lighted compartment (control: 23.50 ± 2.45 s, muscimol: 47.30 ± 4.48 s). The present findings point to involvement of the BLA in the modulation of defensive responses that have been associated with GAD.

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There is accumulating evidence that physical inactivity, associated with the modern sedentary lifestyle, is a major determinant of hypertension. It represents the most important modifiable risk factor for cardiovascular diseases, which are the leading cause of morbidity and mortality for both men and women. In addition to involving sympathetic overactivity that alters hemodynamic parameters, hypertension is accompanied by several abnormalities in the skeletal muscle circulation including vessel rarefaction and increased arteriole wall-to-lumen ratio, which contribute to increased total peripheral resistance. Low-intensity aerobic training is a promising tool for the prevention, treatment and control of high blood pressure, but its efficacy may differ between men and women and between male and female animals. This review focuses on peripheral training-induced adaptations that contribute to a blood pressure-lowering effect, with special attention to differential responses in male and female spontaneously hypertensive rats (SHR). Heart, diaphragm and skeletal muscle arterioles (but not kidney arterioles) undergo eutrophic outward remodeling in trained male SHR, which contributed to a reduction of peripheral resistance and to a pressure fall. In contrast, trained female SHR showed no change in arteriole wall-to-lumen ratio and no pressure fall. On the other hand, training-induced adaptive changes in capillaries and venules (increased density) were similar in male and female SHR, supporting a similar hyperemic response to exercise.

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Vascular calcification decreases compliance and increases morbidity. Mechanisms of this process are unclear. The role of oxidative stress and effects of antioxidants have been poorly explored. We investigated effects of the antioxidants lipoic acid (LA) and tempol in a model of atherosclerosis associated with elastocalcinosis. Male New Zealand white rabbits (2.5-3.0 kg) were fed regular chow (controls) or a 0.5% cholesterol (chol) diet+104 IU/day vitamin D2 (vitD) for 12 weeks, and assigned to treatment with water (vehicle, n=20), 0.12 mmol·kg-1·day-1 LA (n=11) or 0.1 mmol·kg-1·day-1 tempol (n=15). Chol+vitD-fed rabbits developed atherosclerotic plaques associated with expansive remodeling, elastic fiber disruption, medial calcification, and increased aortic stiffness. Histologically, LA prevented medial calcification by ∼60% and aortic stiffening by ∼60%. LA also preserved responsiveness to constrictor agents, while intima-media thickening was increased. In contrast to LA, tempol was associated with increased plaque collagen content, medial calcification and aortic stiffness, and produced differential changes in vasoactive responses in the chol+vitD group. Both LA and tempol prevented superoxide signals with chol+vitD. However, only LA prevented hydrogen peroxide-related signals with chol+vitD, while tempol enhanced them. These data suggest that LA, opposite to tempol, can minimize calcification and compliance loss in elastocalcionosis by inhibition of hydrogen peroxide generation.

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Biliary atresia (BA) is classically described at the neonatal age. However, rare cases of BA in older infants have also been reported. We report four cases of late-onset BA in infants older than 4 weeks (3 males, 1 female), and describe the diagnostic and management difficulties. One of the cases had a late-onset (29 weeks) presentation with a successful surgical procedure. We highlight the importance of this unusual differential diagnosis in infants with cholestatic syndrome, who may benefit from Kasai surgery, regardless of age.

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The Jackfruit tree is one of the most significant trees in tropical home gardens and perhaps the most widespread and useful tree in the important genus Artocarpus. The fruit is susceptible to mechanical and biological damage in the mature state, and some people find the aroma of the fruit objectionable, particularly in confined spaces. The dehydration process could be an alternative for the exploitation of this product, and the relationship between moisture content and water activity provides useful information for its processing and storage. The aim of this study was to determine the thermodynamic properties of the water sorption of jackfruit (Artocarpus heterophyllus Lam.) as a function of moisture content. Desorption isotherms of the different parts of the jackfruit (pulp, peduncle, mesocarp, peel, and seed) were determined at four different temperatures (313.15, 323.15, 333.15, and 343.15 K) in a water activity range of 0.02-0.753 using the static gravimetric method. Theoretical and empirical models were used to model the desorption isotherms. An analytical solution of the Clausius-Clapeyron equation was proposed to calculate the isosteric heat of sorption, the differential entropy, and Gibbs' free energy using the Guggenhein-Anderson-de Boer and Oswin models considering the effect of temperature on the hygroscopic equilibrium.