Standard map in magnetized relativistic systems: fixed points and regular acceleration

We investigate the concept of a standard map for the interaction of relativistic particles and electrostatic waves of arbitrary amplitudes, under the action of external magnetic fields. The map is adequate for physical settings where waves and particles interact impulsively, and allows for a series of analytical result to be exactly obtained. Unlike the traditional form of the standard map, the present map is nonlinear in the wave amplitude and displays a series of peculiar properties. Among these properties we discuss the relation involving fixed points of the maps and accelerator regimes.Comment: Work to appear in Phys. Rev. E. 2 figure

Interfaces in entrepreneurship development: between tradition and innovation

The linkage between tradition and innovation involves specificities and different degrees of complexity, depending on the entrepreneurial activity and economic sector. The paper adopts an institutionalist approach to study the relation between tradition and innovation through the discussion of a specific case: the introduction of innovations in cork production and transformation in a Portuguese territory: Coruche.info:eu-repo/semantics/publishedVersio

Respiratory Complications Before and After Liver Transplant

Respiratory complications before and after liver transplant are common, diverse, and potentially have a negative impact on patient outcomes. In this review, we discuss the most frequent respiratory conditions that patients may develop in the perioperative period. Their prevention and/or treatment may help to maximize the benefit these patients may derive from liver transplant. This review examines diagnostic and therapeutic approaches to these complications for hepatologists, surgeons, and critical care physicians.info:eu-repo/semantics/publishedVersio

Pomares mistos de frutas: alternativa para segurança alimentar e geração de renda no semi-árido Piauiense.

O objetivo do trabalho é contribuir para a melhoria da qualidade de vida das famílias, a partir da melhoria do hábito alimentar e da geração de renda obtida pelo incremento das atividades produtivas desenvolvidas em áreas dos quintais das casas com fruticultura, baseados em práticas e princípios agroecológicos. A experiência está sendo desenvolvida em cinco municípios do Semi-árido piauiense: Oeiras, Colônia do Piauí, Santa Rosa do Piauí, Cajazeiras e São Miguel da Varjota. Os pomares estão sendo instalados em áreas urbanas e periurbanas e em áreas rurais de assentamentos da reforma agrária. A definição das espécies foi feita com base nas características de adaptação ao clima e solo da região e com foco na agroindustrialização, variando em torno de 30 a 60 plantas por quintal que produzirão durante o ano inteiro, com os objetivos de ter frutas para a diversificação e enriquecimento do cardápio, e também como alternativa de renda. As espécies utilizadas são: umbu verdadeiro, umbu-cajá, cajá, caju, manga, goiaba, acerola, goiaba, graviola, maracujá, banana e fruta-pão. O trabalho contribui para a segurança alimentar e geração de renda em áreas rurais e urbanas, em especial da população carente da periferia dos municípios contemplados e de assentados da reforma agrária.Edição dos Resumos do 5º Congresso Brasileiro de Agroecologia. Guarapari, ES, 2007

KINEMATIC ANALYSIS OF STROKE CYCLE TO AN INTERNATIONAL ATHLETE ON CANOEING -K1

INTRODUCTION -The purpose of this study is the cinematic analysis of the strake cycle done on a simulator, by an athlete of the modality with an international curriculum. This analysis has allowed to describe in detail the technique of stroke and its expression on quantitative terms for parameters like: time, velocity, articulated and absolute angles, the trajectory of the whole body centre gravity and of the corporal segments. Bearing the lack of biomechanical studies on this area and the increase of the number of practitioners in Portugal, this knowledge could contribute to a better understanding of the training process. MATERIAL AND METHOD5 -We have analysed one of the most representative athletes of the National Canoe Federation, a 32 year-old men, 90 Kg of weight and 187 cm of height. We used the video camera to "catch" the strake cycle during a training session. After this we have analysed the cinematic parameters, using a bidimensional computer programme "Peak Performance 5 -Motion measurement system" from Peak Performance Technologies, Inc.. RE5ULT5 -We verified small oscillations of the centre of gravity (c. g.) on the sagital plane (x =4 cm and y =3,5 cm) during the strake cycle. The horizontal velocity (vx) of the left hand was analysed, having its maximum values at the vertical position of the paddle: Vx (aerial, phase) = 2,1 m/s; Vx (aquatic phase) = 1,1 m/s. The zero values of Vx were found in the horizontal position of the paddle. On the other hand, vertical velocity (vy) reaches its maximum at the horizontal position of the paddle and was zero when the paddle is vertical. Analysing the angle of the segment trunk (defined by the shoulder and hip) in relation to the vertical axis, we observed a variation of 25,8° The angle corresponding to the shoulder forward inclination was 14,7° and the angle corresponding to the backward inclination was 11,1 ° The knee angle showed for the maximal extension and flexion of the leg was 163,3° and 129,7°, respectively The maximal and minimal ankle angles were 89,7° and 134,6° CONCLU510NS -The c.g. movement in sagital plane can cause smooth rotations of the kayak in real conditions. There is a relation between the knee and ankle angles, which is, the extension of the knee is related to the ankle plantar flexion and the flexion of the knee is related to the ankle dorsal flexion. As it is in the aquatic phase that one founds the maximum values for horizontal velocity (the paddle is vertical) it seems that the simulator offers a great relation between the horizontal velocity and the propulsion of the kayak. This investigation should contribute to an improvement of the training process specially in technique, because it allows a comparison between the simulate situation and real situation

Aromatic, medicinal, and local herbs: The critical role of networks

The purpose of the communication is to present some research results on the sector of aromatic and medicinal herbs located in different regions of the Portuguese territory. The focus of the presentation is the role of local development associations and networks in the development of the sector. Aromatic and medicinal plants are very important in the Mediterranean diet. Their presence in gourmet food and the recipes of well-known chefs gave an important impulse in the prestige and, therefore, demand of the product. The cultivation of aromatic and medicinal herbs has economic, social, and environmental impacts on the territory. Besides the creation of employment and the possibility of an, principal or complementary, income source, this production provides the improvement of biodiversity and the occupation of rural areas. They are mostly cultivated in small and very small farms, both in developing and developed countries (Kwankhao & Indaratna, 2020; Matthews & Jack, 201; Schunko, et al, 2019; Unati et al, 2016; Yamoah et al, 2014). This characteristic presents many challenges in different dimensions of business development through the value chain, namely commercialization. That is why the connection and the establishment of partnerships with other actors, such as local development associations, and other producers, have an important role, since they provide the scale and critical resources towards the success of this initiatives. The case study selected, EPAM, provides the empirical setting to explore this sector regarding the role of networks. With these goals in mind, the presentation is structured in through the following topics: after the revision of literature, and the design of a conceptual framework, the communication presents the methodological options, and the results. The presentation finishes with the identification of limitations of the research and concluding remarks.info:eu-repo/semantics/publishedVersio