Preparação de resinas de poliuretana à base de óleo de mamona e dietanolamina

The aim of this work was the preparation of polyols from reactions between castor oil and dietanolamine to increase the hydroxyl content and the network degree in the products to application in electronic devices. The polyols and the mixtures obtained were characterized by nuclear magnetic ressonance. Castor oil (CO) is a natural triglyceride - based polyol possessing hydroxyl groups, which allow several reactions that produce many different products. Among them are the polyurethanes (PU), which have been considered an ideal product for the covering of electricelectronic circuits, due to their excellent electrical, shock-absorbing, solvents resistance and hydrolytic stability properties. About 90% of the fatty acids present in the castor oil are ricinoleic acid (12-hydroxyoleic acid), while the remaining 10% correspond to non-hydroxylated fatty acids, mainly linoleic and oleic acids. The chemical analysis of castor oil indicates a hydroxyl number of 2.7. In this work, a polyol was obtained by the reaction of the CO with diethanolamine (DEA), in order to elevate the hydroxyl value from 160 to 230 or to 280 mgKOH/g, and characterized by nuclear magnetic resonance (NMR) 1H and 13C (Mercury 200). The polyadition of the resulting polyol with isophorone diisocianate (IPDI) was carried out at 60°C, and the reaction kinetics was followed by rheological measurements in a Haake RS150 rheometer. The electrical properties were determined in a HP LCR Meter 4262A, at 1.0 Hz and 10.0 KHz. The chemical analysis showed that the polyols obtained presented hydroxyl number from 230 to 280 mgKOH/g. The polyadition reaction with IPDI produced polyurethane resins with the following properties: hardness in the range from 45 shore A to 65 shore D (ASTM D2240); a dielectric constant of 3.0, at 25°C (ASTM D150). Those results indicate that the obtained resins present compatible properties to the similar products of fossil origin, which are used nowadays for covering electric-electronic circuits. Therefore, the PUs from castor oil can be considered as alternative materials of renewable source, free from the highly harmful petroleum - derived solvents

Evidence of reciprocal connections between the dorsal raphe nucleus and the retina in the monkey Cebus apella

Possible connections between the retina and the raphe nuclei were investigated in the monkey Cebus apella by intraocular injection of cholera toxin B subunit (CTb). CTb-positive fibers were seen in the lateral region of the dorsal raphe nucleus (DR) on the side contralateral to the injection, and a few labeled perikarya were observed in the lateral portion of the DR on the ipsilateral side. Our findings suggest that direct and reciprocal connections between the retina and DR may exist in Cebus apella. These connections might be part of an important pathway through which the light/dark cycle influences the Activity and/or functional status of raphe neurons, with potential effects on a broad set of neural and behavioral circuits. (c) 2007 Elsevier B.V. All rights reserved.

Comparison of lung tissue concentrations of nebulized ceftazidime in ventilated piglets: ultrasonic versus vibrating plate nebulizers

Objective: To compare the efficiency of an Aeroneb Pro vibrating plate and an Atomisor MegaHertz ultrasonic nebulizer for providing ceftazidime distal lung deposition.Design: In vitro experiments. One gram of cetazidime was nebulized in respiratory circuits and mass median aerodynamic diameter of particles generated by ultrasonic and vibrating plate nebulizers was compared using a laser velocimeter. In vivo experiments. Lung tissue concentrations and extrapulmonary depositions were measured in ten anesthetized ventilated piglets with healthy lungs that received 1 g of ceftazidime by nebulization with either an ultrasonic (n = 5), or a vibrating plate (n = 5) nebulizer.Setting: A two-bed Experimental Intensive Care Unit of a University School of Medicine.Intervention: Following sacrifice, 5 subpleural specimens were sampled in dependent and nondependent lung regions for measuring ceftazidime lung tissue concentrations by high-performance liquid chromatography.Measurements and results: Mass median aerodynamic diameters generated by both nebulizers were similar with more than 95% of the particles between 0.5 and 5 mu m. Lung tissue concentrations were 553 +/- 123 [95% confidence interval: 514-638] mu g g(-1) using ultrasonic nebulizer, and 452 +/- 172 [95% confidence interval: 376-528] mu g g(-1) using vibrating plate nebulizers (NS). Extrapulmonary depositions were, respectively, of 38 +/- 5% (ultrasonic) and 34 +/- 4% (vibrating plate) (NS).Conclusions: Vibrating plate nebulizer is comparable to ultrasonic nebulizers for ceftazidime nebulization. It may represent a new attractive technology for inhaled antibiotic therapy.

Avaliação da execução de aplicações orientadas à dados na arquitetura de redes em chip IPNoSys

The increasing complexity of integrated circuits has boosted the development of communications architectures like Networks-on-Chip (NoCs), as an architecture; alternative for interconnection of Systems-on-Chip (SoC). Networks-on-Chip complain for component reuse, parallelism and scalability, enhancing reusability in projects of dedicated applications. In the literature, lots of proposals have been made, suggesting different configurations for networks-on-chip architectures. Among all networks-on-chip considered, the architecture of IPNoSys is a non conventional one, since it allows the execution of operations, while the communication process is performed. This study aims to evaluate the execution of data-flow based applications on IPNoSys, focusing on their adaptation against the design constraints. Data-flow based applications are characterized by the flowing of continuous stream of data, on which operations are executed. We expect that these type of applications can be improved when running on IPNoSys, because they have a programming model similar to the execution model of this network. By observing the behavior of these applications when running on IPNoSys, were performed changes in the execution model of the network IPNoSys, allowing the implementation of an instruction level parallelism. For these purposes, analysis of the implementations of dataflow applications were performed and compared

Uma nova proposta de antena planar multibanda para comunicações móveis

The great interest observed in wireless communication systems has required the development of new configurations of microstrip antennas, because they are easily built and integrated to other microwave circuit components, which is suitable for the construction and development of planar antenna arrays and microwave integrated circuits. This work presents a new configuration of tapered microstrip antenna, which is obtained by impressing U-slots on the conducting patch combined with a transmission line matching circuit that uses an inset length. It is shown that the use of U-slots in the microstrip antenna conducting patch excites new resonating modes, that gives a multiband characteristic for the slotted microstrip antenna, that is suitable for applications in communication systems that operates several frequencies simultaneously. Up to this date, the works reported in the literature deals with the use of Uslotted microstrip rectangular antennas fed by a coaxial probe. The properties of a linear array of microstrip patch tapered antennas are also investigated. The main parameters of the U slotted tapered microstrip antennas are investigated for different sizes and locations of the slots impressed on the conducting patch. The analysis of the proposed antenna is performed by using the resonant cavity and equivalent transmission line methods, in combination with a parametric study, that is conducted by the use of the Ansoft Designer, a commercial computer aided microwave software well known by its accuracy and efficiency. The mentioned methods are used to evaluate the effect in the antennas parameters, like resonant frequency and return loss, produced by variations of the antenna structural parameters, accomplished separately or simultaneously. An experimental investigation is also developed, that consists of the design, construction and measurement of several U slotted microstrip antenna prototypes. Finally, theoretical and simulated results are presented that are in agreement with the measured ones. These results are related to the resonating modes identification and to the determination of the main characteristics of the investigated antennas, such as resonant frequency, return loss, and radiation pattern

Circuitos espaciais de produção da atividade boneleira: o uso dos territórios de Caicó, Serra Negra do Norte e São José do Seridó

Cette étude a été fondée sur la reconaissance, la description et l'analyse du circuit spatial de la production de l activité des fabriques des casquettes dans la région du Seridó Potiguar. L activité des fabriques des casquettes est située dans les villes de Caicó, Serra Negra do Norte e São José do Seridó, qui forment le pôle de fabriques de casquettes, composé de soixante-quatre (64) unités de fabrication, le deuxième plus grand producteur de casquettes au Brésil. Dans la condition de base géographique, l'opérationnalisation du concept de circuits spatiales de la production a été essentielle à la compréhension de l'utilisation du territoire et de l'indivisibilité de l'espace, du fournisseur de matières premières au consommateur final, comprenant les étapes des matières premières, la main-d'oeuvre, le stockage, les transports, le commerce et la consommation dans la période actuelle, dans laquelle les instances de la production, la circulation, la distribution et de la consommation sont spatialement diffus. Sur la base de l'identification et de la localisation de ces étapes et des principaux acteurs impliqués dans la activité des fabriques de casquettes, une configuration de circuit spatial de la production a été élaborée, en s'interprétant l'utilisation des territoires par les instances productives. L'interprétation des étapes de production a identifié que les entreprises liées à l'Association Seridoense des Fabricants de Casquettes agissent plus efficacement sur le territoire que celles nonassociées, alors que toujours elles investissent dans des nouveaux équipements, en augmentant sa puissance technique pour se renforcer avant un marché si compétitif comme celui des casquettes. En examinant la contribution de la fabrication des casquettes à l'utilisation actuelle des territoires de la coupe, nous avons appris que les activités complémentaires et des matières premiéres nécessaires à sa réalisation se trouvent dans leur environnement géographique. Ainsi, la proximité spatiale entre les étapes de la fabrication des casquettes fait entrevoir la matérialité du territoire, conférée dans la coexistence des techniques passées et présentes, et l'ensemble des actions effectuées par un certain nombre de travailleurs sociaux qui collaborent à la création du circuit spatial de la production de l activité des fabriques des casquettes. Cette étude a confirmé que les fabriques des casquettes sont organisées sous la forme de cellules de production, continues ou discontinues, dont les équipements et les machines à coudre industrielles obéissent à la logique d'une production de plus en plus standardisée. Ce circuit spatial de la production contribue à l'utilisation actuelle des territoires de Caicó, Serra Negra do Norte et de São José do Seridó car il amplifie le mouvement du commerce et des relations entre les lieux, à travers la dynamique des flux des personnes, des biens et des produits, en constante circulation, guidées par la division du travail entre les étapes productives

Feira livre e circuitos da economia urbana: um estudo da feira da Pedra, em São Bento (PB)

The Feira da Pedra is an extension of the open fair of São Bento in the State of Paraiba. It is a system of trade in textile goods produced by textile industry in manufacturing of hammocks and derivatives of this industry, present in some cities in the state of Paraiba and Rio Grande do Norte, as a survival strategy, inserted in the list of tertiary and retail of the urban economics of this city. It is thereby aimed to discuss about the urban economics, reflecting on the open fair system from the two circuits of urban economy, mainly in the context of the dynamics of the current period of geographic space, the technical-scientific-informational period, as the specific empirical object, the Feira da Pedra of São Bento (PB). For this, this research was carried out in two stages of operation: a) surveys of secondary data and b) primary data collection which were reported an operational triad: I) literature; II) documentary research, and III) research of field. The presence of the Feira da Pedra in São Bento has shown us one of the most important characteristics of this city, in order to present major economic, social and cultural benefits to the local population, and contribute to (re) production of sertanejo space, making lower part of the circuit of its urban economy. This activity has entailed several dynamics for urban space in this city, mainly because of attracting large numbers of people, carrying typical actions of its relationship with the urban space are são-bentense and built environment. Thus, its importance is not only a local and regional phenomenon, but also a cultural reference of a place in the geographical area of many paraibanos and norte-rio-grandenses subjects, as the case of this activity has brought to its weekly routine, this product resulting from the textile working of this area of Sertão Paraibano and Seridó Potiguar

O Circuito inferior da economia urbana em Mossoró: a dinâmica do comércio ambulante

This study was based on the analysis and understanding of the dynamics of the lower circuit of the economy and the size of the street trading in the city of Mossoro (RN). The operationalization of the theory of the two circuits of the urban economy, based on Santos (2008a) was essential to understand the street trading as part of the entire city of Mossoro. It was given emphasis on the study of the lower circuit of the economy and its coverage in the street trading in the commercial center of the city, specifically in street trading in Coronel Gurgel. The dynamics of that street reveals the different ways that the territory is used simultaneously by different social actors as pedestrians, consumers, business owners, and especially by street vendors. These vendors occupy the spaces along the streets of the city commercial center, placing their tents or stalls, especially on sidewalks, excellent strategic locations for the marketing of their products, due to the large influx of people seeking goods and services nearby. As methodological and technical procedures for gathering primary data, we opted for the use of questionnaires and interviews, with many users of the lower circuit, both consumers and vendors. The analysis of these questionnaires, along with the theoretical background, has revealed that there are several social and political conflicts related to the use of public spaces, such as sidewalks and flowerbeds, in the city commercial center, and that these conflicts are increasingly demonstrating that vendors need a space endowed with infrastructure to conduct their activities. The lack of efficiency of the government, as well as the slowness of their actions to organize a space that is able to properly fit salespersons, constitutes one of the main problems faced by these small traders who have limited financial resources and materials to get their activities through in the globalized world. At the same time, this study revealed the importance of these agents, as the last link of the urban economy, in the distribution of various consumer goods, enabling the satisfaction of some needs of the population, especially the poorer people

Os marcos da paisagem da cidade no contexto da trama urbana de Natal/RN: um estudo a partir do Morro do Careca, o Midway Mall, o Pórtico dos Reis Magos e a Ponte Newton Navarro

The present work is a study on the functions performed by landmarks landscape Natal / RN in the urban fabric, in the case of Midway Mall, the Portico dos Reis Magos, the Morro do Careca and Newton Navarro Bridge. For such goals established itself as analyze the functionality of the milestones presented here in the urban fabric; discuss the importance of these landmarks of the city landscape in the process of urbanization of Natal, and identify and spatialize actions related to the use of territories where are located landmarks, discussing their reflections. To achieve these goals we chose to use as a literature search procedures, the problematic concept, working with oral sources, and reading speechless. To support this research the main concepts were worked landscape, city, landmark, public space, circuits, among others. After going over the theory, consistent with the empirical data, it appears that the landmarks studied here have different functions and features, but all carry different forms of fascination for the public and visitors to the city, and every man your way, influence the public space, land speculation and feature importance in the process of urbanization of Natal

A Ceasa-RN e os circuitos da economia urbana: a circulação de hortifrutigranjeiros em Natal-RN

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Setor terciário e informalidade: algumas especificidades da (re)produção do espaço urbano de Bayeux-PB

This work has as study object the tertiary sector and (the re)production of the urban space of Bayeux-PB. For in such a way, one became necessary to the construction of a theoretical boarding that context the national reality, to be able itself to understand the reality local. This way to construct allowed an opening of the field of vision how much to the relevance of if ahead studying the tertiary sector and its weight of the current configuration of the society in a country as Brazil, e especially in a city of a State northeastern, as it is the case of Bayeux. The theoretical boarding had as base the two circuits of the urban economy, the productive reorganization and the transformations in the world of the work, as well as, the space organization and the distinction between the economic and social space of the tertiary activities, from the logic of functioning of the establishments: the regulation. Besides working with referring official data to the tertiary sector, the empirical study it had as reference one hundred and sixty and establishments tertiary, located in four axles of circulation of the city of Bayeux - PB, which are: Av. Liberdade, Av. Engenheiro de Carvalho, Av. Francisco Marques da Fonseca and Av. Marechal Rondon, that they had appeared in such a way stimulated for the processes of urbanization and industrialization lived deeply from years 70 in the "Great João Pessoa" how much, in the countries of the underdeveloped capitalist world, as Brazil. Being thus, the objective of the work was to study the tertiary sector and its relation with (the re)production of the urban space, standing out the functioning logic

O Circuito espacial de produção do biodiesel: configuração no território brasileiro e uso do território Norte-Rio-Grandense

This research aims to understand the use of the territory from the Rio Grande do Norte to the circuit spatial of production from the Biodiesel understanding it as part of the national context. The introduction of biodiesel into the Brazilian energy matrix begins to take shape in the year 2005 with the implementation of the National Program for Production and Use of Biodiesel (NPPB). This is anchored on three pillars: social inclusion (through family agriculture), environmental sustainability and economic viability. The NPPB consists of a set of standards, which turned into shares and distributed by almost all the national territory. Our reflection assumes that the places accommodating different forms of productive activities and, thus, the performance of the circuit space of biodiesel production depends on several factors, including the configuration of the territory they receive this new nexus economic. Understanding that the places by their technical content determine the realization of productive activities, it was found that the inclusion of this circuit space production in Rio Grande do Norte, reveals the reality expressed in the national territory, where some places are endowed with a privileged technical content and other extremely poor infrastructure. As our research could confirm the circuit space of biodiesel production that is expressed in the way plants are distributed within the country (mostly in South-Central), in more significant participation of small farmers in the South in the supply of raw material for the production of biodiesel and the main raw material used for the production of agrofuels (soybeans, whose production sector is highly consolidated and technified). Already the project materialization of NPPB regarding the settlements and communities of the Rio Grande do Norte State, we observed that the "event" or advent of realization encountered a technical means lacking in infrastructure that need to be molded to the needs of production, or is to cultivate castor beans or sunflower would be needed inputs and implements that farmers don´t have. Given the above, the research concludes that, as proposed previously, the use of the territory of Rio Grande do Norte to this circuit has summarized the performance of experiments, either with regard to the participation of family farmers as suppliers of raw materials, including the development of related research in the stage of production fuel oil by Petrobras. This finding came from research done from the concept of "spatial circuits of production," which allowed the verification of the circuit that steps outlined in Potiguar territory. Regarding the inclusion of family farmers in the productive circuit in RN, research reveals that, in the manner as has been done, it is doomed to failure. Furthermore, we dare say that this persistence in trying to put these family farmers, the way is being made, and the resulting successive failures, indicating that social inclusion advocated by NPPB not take place, and that this production circuit relies on the same logic circuit concentrated and exclusive space for ethanol production

Experience-dependent upregulation of multiple plasticity factors in the hippocampus during early REM sleep

Sleep is beneficial to learning, but the underlying mechanisms remain controversial. The synaptic homeostasis hypothesis (SHY) proposes that the cognitive function of sleep is related to a generalized rescaling of synaptic weights to intermediate levels, due to a passive downregulation of plasticity mechanisms. A competing hypothesis proposes that the active upscaling and downscaling of synaptic weights during sleep embosses memories in circuits respectively activated or deactivated during prior waking experience, leading to memory changes beyond rescaling. Both theories have empirical support but the experimental designs underlying the conflicting studies are not congruent, therefore a consensus is yet to be reached. To advance this issue, we used real-time PCR and electrophysiological recordings to assess gene expression related to synaptic plasticity in the hippocampus and primary somatosensory cortex of rats exposed to novel objects, then kept awake (WK) for 60 min and finally killed after a 30 min period rich in WK, slow-wave sleep (SWS) or rapid-eye-movement sleep (REM). Animals similarly treated but not exposed to novel objects were used as controls. We found that the mRNA levels of Arc, Egr1, Fos, Ppp2ca and Ppp2r2d were significantly increased in the hippocampus of exposed animals allowed to enter REM, in comparison with control animals. Experience-dependent changes during sleep were not significant in the hippocampus for Bdnf, Camk4, Creb1, and Nr4a1, and no differences were detected between exposed and control SWS groups for any of the genes tested. No significant changes in gene expression were detected in the primary somatosensory cortex during sleep, in contrast with previous studies using longer post-stimulation intervals (>180 min). The experience-dependent induction of multiple plasticity-related genes in the hippocampus during early REM adds experimental support to the synaptic embossing theory.

Brain serotonin blockade and paradoxical salt intake in rats

Serotonin antagonism in the lateral parabrachial nucleus (LPBN) enhances sodium appetite induced by hypovolaemia and angiotensin-mineralocorticoid activation, but produces no sodium intake in euhydrated animals. In the present work, male adult rats (n=21) that received bilateral injections of the serotonergic antagonist methysergide (4 mug/ 0.2 mul) into the LPBN combined to intragastric load of 2 M NaCl (2 ml/rat), ingested hypertonic NaCl (ingestion of 4.3+/-1.6 ml/2 h of 0.3 M NaCl versus vehicle into LPBN: 0.2+/-0.2 ml/2 h, P<0.05). Methysergide- and vehicle-treated animals also ingested water (9.5+/-0.7 and 7.2+/-0.5 ml/2 h, respectively, P>0.05) as expected from the state of cell dehydration produced by the load. Ingestion of water (11.0+/-1.2 ml/2 h), and of 0.3 M NaCl (1.1+/-0.7 ml/2 h) were not altered by methysergide in NaCl loaded rats with misplaced LPBN injections (n=15). The ingestion of hypertonic NaCl by rats with serotonergic blockade in the LPBN suggests that the circuits subserving sodium appetite are activated, but at the same time strongly inhibited through the LPBN, during cell dehydration. (C) 2003 IBRO. Published by Elsevier Ltd. All rights reserved.

Alpha(2)-adrenergic activation in the lateral parabrachial nucleus induces NaCi intake under conditions of systemic hyperosmolarity

The inhibition of sodium intake by increased plasma osmolarity may depend on inhibitory mechanisms present in the lateral parabrachial nucleus. Activation of alpha(2)-adrenergic receptors in the lateral parabrachial nucleus is suggested to deactivate inhibitory mechanisms present in this area increasing fluid depletion-induced 0.3 M NaCl intake. Considering the possibility that lateral parabrachial nucleus inhibitory mechanisms are activated and restrain sodium intake in animals with increased plasma osmolarity, in the present study we investigated the effects on water and 0.3 M NaCl intake produced by the activation of alpha(2)-adrenergic receptors in the lateral parabrachial nucleus in rats with increased plasma osmolarity. Male Holtzman rats with stainless steel cannulas implanted bilaterally into the lateral parabrachial nucleus were used. One hour after intragastric 2 M NaCl load (2 ml), bilateral injections of moxonidine (alpha(2)-adrenergic/imidazoline receptor agonist, 0.5 nmol/0.2 mu l, n=10) into the lateral parabrachial nucleus induced a strong ingestion of 0.3 M NaCl intake (19.1 +/- 5.5 ml/2 h vs. vehicle: 1.8 +/- 0.6 ml/2 h), without changing water intake (15.8 +/- 3.0 ml/2 h vs. vehicle: 9.3 +/- 2.0 ml/2 h). However, moxonidine into the lateral parabrachial nucleus in satiated rats not treated with 2 M NaCl produced no change on 0.3 M NaCl intake. The pre-treatment with RX 821002 (alpha(2)-adrenergic receptor antagonist, 20 nmol/0.2 mu l) into the lateral parabrachial nucleus almost abolished the effects of moxonidine on 0.3 M NaCl intake (4.7 +/- 3.4 ml/2 h). The present results suggest that alpha(2)-adrenergic receptor activation in the lateral parabrachial nucleus blocks inhibitory mechanisms, thereby allowing ingestion of hypertonic NaCl under conditions of extracellular hyperosmolarity. We suggest that during cell dehydration, circuits subserving sodium appetite are activated, but at the same time strongly inhibited through the lateral parabrachial nucleus. (c) 2006 IBRO. Published by Elsevier Ltd. All rights reserved.