O efeito da carga compressiva repetitiva sobre a placa de crescimento : estudo experimental em ratos

Os impactos repetitivos decorrentes do esporte podem interferir no crescimento ósseo. Com o objetivo de tentar elucidar o efeito mecânico dos impactos repetitivos sobre a placa de crescimento ósseo, da tíbia proximal, um estudo experimental em ratos foi realizado. Inicialmente, foi desenvolvida uma máquina para a produção de impactos repetitivos na tíbia dos ratos. Os impactos repetitivos foram produzidos na tíbia direita em uma amostra de 60 ratos wistar, divididos em 6 grupos de 10 cada, sendo a esquerda o controle. A magnitude de impacto foi de aproximadamente 3,5 vezes a massa corporal dos ratos. Após os dias de impacto, os ratos foram sacrificados e as tíbias foram medidas. Em seguida um estudo histológico da placa de crescimento foi realizado. Foram medidas, a espessura total da placa de crescimento, a espessura da zona de repouso, de proliferação e hipertrófica e de calcificação juntas. Os resultados mostraram diferença significativa no comprimento da tíbia nos testes intra-grupos para os grupos 3, 4,e 5 (p≤0,05), e intergrupos para a tíbia direita e esquerda (p≤0,05). A placa de crescimento mostrou uma menor espessura significativa na tíbia direita (p≤0,05). Na esquerda não houve alteração significativa da espessura da placa (p=0,109). As zonas de repouso e proliferativa da placa da tíbia direita, e o número médio de células nas colunas da zona proliferativa apresentaram diferenças significativas intergrupos (p= 0,013, p=0,042 e p=0,017, respectivamente). As zonas hipertrófica e de calcificação apresentaram diferença significativas nas tíbias direita e esquerda (p 0,048 e 0=0,020, respectivamente). As análises múltiplas confirmaram que não existiram evidências de calcificação precoce da placa, com a magnitude de impacto produzida. Não houve mudança significativa nas zonas hipertrófica e de calcificação. A conclusão é de que os impactos repetitivos diminuem a espessura da placa de crescimento proximal da tíbia durante a puberdade, principalmente quando o tempo de impacto ultrapassa a metade do período de puberdade. Com a interrupção de 10 dias na produção dos impactos, permaneceu a diminuição da espessura da placa proximal da tíbia. A cargas de impactos de aproximadamente 3,5 vezes a massa corporal não são suficientes para exibir evidências de calcificação precoce da placa de crescimento.

Multiple equilibria and protectionism

In a nonnative approach, I analyze trade policies when the industrial sector genentes positive extemalities in production, and there are adjustments costs to changing production from one sector to the other. Protectionist trade policy can make workers intemalize the benetits from moving into the industrial sector, but it is a second best policy as it also causes consumption distortions. I show that if the govemment is able to fully commit to its tariff schedule for the future, the welfare maximizing policy is to maintain a positive tariff forever, even after all adjustment has already taken place . However, if the govemment is not able to commit at all, the only time consistent policy is zero tariff at any point in time. The time inconsistency of the full commitment policy is derived from the fact that in the model only production needs interference, and the production distortion is lagged one period with respect to the tariff wbile the consumption distortion is simultaneous to the tariff. In the intermediary case, i.e., when the government can commit for a limited period of time, the time consistent optimal tariff will be positive but lower than the "full commitment" tariff. This result indicates that some institutions that have always been considered pure sources of inefficiency, such as protectionist lobbying, may in fact be welfare improving in some cases!

Multilayer optimization in radio resource allocation for the packet transmission in wireless networks

In the last decade mobile wireless communications have witnessed an explosive growth in the user’s penetration rate and their widespread deployment around the globe. It is expected that this tendency will continue to increase with the convergence of fixed Internet wired networks with mobile ones and with the evolution to the full IP architecture paradigm. Therefore mobile wireless communications will be of paramount importance on the development of the information society of the near future. In particular a research topic of particular relevance in telecommunications nowadays is related to the design and implementation of mobile communication systems of 4th generation. 4G networks will be characterized by the support of multiple radio access technologies in a core network fully compliant with the Internet Protocol (all IP paradigm). Such networks will sustain the stringent quality of service (QoS) requirements and the expected high data rates from the type of multimedia applications to be available in the near future. The approach followed in the design and implementation of the mobile wireless networks of current generation (2G and 3G) has been the stratification of the architecture into a communication protocol model composed by a set of layers, in which each one encompasses some set of functionalities. In such protocol layered model, communications is only allowed between adjacent layers and through specific interface service points. This modular concept eases the implementation of new functionalities as the behaviour of each layer in the protocol stack is not affected by the others. However, the fact that lower layers in the protocol stack model do not utilize information available from upper layers, and vice versa, downgrades the performance achieved. This is particularly relevant if multiple antenna systems, in a MIMO (Multiple Input Multiple Output) configuration, are implemented. MIMO schemes introduce another degree of freedom for radio resource allocation: the space domain. Contrary to the time and frequency domains, radio resources mapped into the spatial domain cannot be assumed as completely orthogonal, due to the amount of interference resulting from users transmitting in the same frequency sub-channel and/or time slots but in different spatial beams. Therefore, the availability of information regarding the state of radio resources, from lower to upper layers, is of fundamental importance in the prosecution of the levels of QoS expected from those multimedia applications. In order to match applications requirements and the constraints of the mobile radio channel, in the last few years researches have proposed a new paradigm for the layered architecture for communications: the cross-layer design framework. In a general way, the cross-layer design paradigm refers to a protocol design in which the dependence between protocol layers is actively exploited, by breaking out the stringent rules which restrict the communication only between adjacent layers in the original reference model, and allowing direct interaction among different layers of the stack. An efficient management of the set of available radio resources demand for the implementation of efficient and low complexity packet schedulers which prioritize user’s transmissions according to inputs provided from lower as well as upper layers in the protocol stack, fully compliant with the cross-layer design paradigm. Specifically, efficiently designed packet schedulers for 4G networks should result in the maximization of the capacity available, through the consideration of the limitations imposed by the mobile radio channel and comply with the set of QoS requirements from the application layer. IEEE 802.16e standard, also named as Mobile WiMAX, seems to comply with the specifications of 4G mobile networks. The scalable architecture, low cost implementation and high data throughput, enable efficient data multiplexing and low data latency, which are attributes essential to enable broadband data services. Also, the connection oriented approach of Its medium access layer is fully compliant with the quality of service demands from such applications. Therefore, Mobile WiMAX seems to be a promising 4G mobile wireless networks candidate. In this thesis it is proposed the investigation, design and implementation of packet scheduling algorithms for the efficient management of the set of available radio resources, in time, frequency and spatial domains of the Mobile WiMAX networks. The proposed algorithms combine input metrics from physical layer and QoS requirements from upper layers, according to the crosslayer design paradigm. Proposed schedulers are evaluated by means of system level simulations, conducted in a system level simulation platform implementing the physical and medium access control layers of the IEEE802.16e standard.

Transmission network expansion planning considering multiple generation scenarios

This paper presents a mathematical model and a methodology to solve a transmission network expansion planning problem considering open access. The methodology finds the optimal transmission network expansion plan that allows the power system to operate adequately in an environment with multiples generation scenarios. The model presented is solved using a specialized genetic algorithm. The methodology is tested in a system from the literature. ©2008 IEEE.

Retificador boost entrelaçado com elevado fator de potência e sem ponte de diodos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Consumo alimentar, estado nutricional e resposta precoce dos fatores de risco relacionados à síndrome metabólica de pacientes submetidos ao transplante de células-tronco hematopoéticas

Pós-graduação em Alimentos e Nutrição - FCFAR

Fano interference and a slight fluctuation of the Majorana hallmark

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Perfil materno e dos recém-nascidos nascidos vivos na primeira década do século XXI em município do interior paulista com ênfase na prematuridade

The concern with infant mortality has been a priority in public policies, especially for Brazil to achieve the Millennium Development Goal number four: reducing child mortality by 75% by the year 2015. It is known that prematurity has an intimate relationship with mortality of children under one year and therefore it is necessary an effective intervention in risk factors linked to premature births. To evaluate the profile of mothers and newborn babies living in Botucatu-SP, in the period 2001 to 2009, focusing on prematurity. A quantitative study, retrospective, descriptive, epidemiological, from the Information System Newborn Alive. The prevalence of preterm births was 15.1%, and low birth weight 14.7%. Among infants, the Apgar score below 7 at 1 and at 5 minutes was 13.1% and 2.4% respectively. Considering the total of pregnant women studied, 20.3% were adolescents and 10.3% were aged 35 years or more and most (63.2%) had eight or more years of school approval. The profile of mothers of premature infants shows that 23.6% were teenagers, 14.1% had at least 35 years and 60.4% had at least primary education. With regard to premature deliveries, caesarean sections and 58.4% were between the total newborns, this type of delivery was achieved in 46.6% of cases. Prematurity was associated with an Apgar score below seven in the first and fifth minutes of life, presence of malformation and multiple pregnancy. Among maternal variables, prematurity was associated with extremes of maternal age, maternal education, history of stillbirth, primiparas, white and presence of the mother's partner. With regard to delivery was associated with cesarean section and outside the hospital. This study assessed maternal characteristics associated with prematurity and point out how relevant the pregnancies at the extremes of age and those that occur in women with low education level, indicating the interference... (Complete abstract click electronic access below)

Pan-Assay interference compounds (PAINS): warning signs in biochemical-pharmacological evaluations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Caring Teacher: A Multiple Case Study That Looks at What Teachers Do and Believe about Their Work With At-Risk Students

Caring teachers have been identified as a critical component of successful interventions with at-risk students, however just what constitutes a caring teacher is less well understood. Specifically, what are the behaviors, characteristics, and beliefs of caring teachers, and how are they impacted by the contexts within which they work? The purpose of this multiple case study was to understand more about caring teachers who work with at-risk students in secondary schools located in a Midwestern city and thereby to add complexity to the literature. Two middle school teachers and two high school teachers were recruited to participate. They were observed on multiple occasions and interviewed twice. The data from these observations and interviews were initially analyzed case by case; the cross case analysis based on the results from the individual case resulted in 6 themes that were present across the four cases. The following themes were identified: the role of relationships, perspective on at-risk students, providing opportunities for students to develop a positive sense of themselves, the value of a positive classroom experience for both students and teacher, negotiating power, and flexibility. Implications of this research for psychologists, educators, and policy makers, as well as future research are also discussed.

A comparative transcriptome analysis reveals expression profiles conserved across three Eimeria spp. of domestic fowl and associated with multiple developmental stages

Coccidiosis of the domestic fowl is a worldwide disease caused by seven species of protozoan parasites of the genus Eimeria. The genome of the model species, Eimeria tenella, presents a complexity of 55-60 MB distributed in 14 chromosomes. Relatively few studies have been undertaken to unravel the complexity of the transcriptome of Eimeria parasites. We report here the generation of more than 45,000 open reading frame expressed sequence tag (ORESTES) cDNA reads of E. tenella, Eimeria maxima and Eimeria acervulina, covering several developmental stages: unsporulated oocysts, sporoblastic oocysts, sporulated oocysts, sporozoites and second generation merozoites. All reads were assembled to constitute gene indices and submitted to a comprehensive functional annotation pipeline. In the case of E. tenella, we also incorporated publicly available ESTs to generate an integrated body of information. Orthology analyses have identified genes conserved across different apicomplexan parasites, as well as genes restricted to the genus Eimeria. Digital expression profiles obtained from ORESTES/EST countings, submitted to clustering analyses, revealed a high conservation pattern across the three Eimeria spp. Distance trees showed that unsporulated and sporoblastic oocysts constitute a distinct clade in all species, with sporulated oocysts forming a more external branch. This latter stage also shows a close relationship with sporozoites, whereas first and second generation merozoites are more closely related to each other than to sporozoites. The profiles were unambiguously associated with the distinct developmental stages and strongly correlated with the order of the stages in the parasite life cycle. Finally, we present The Eimeria Transcript Database (http://www.coccidia.icb.usp.br/eimeriatdb), a website that provides open access to all sequencing data, annotation and comparative analysis. We expect this repository to represent a useful resource to the Eimeria scientific community, helping to define potential candidates for the development of new strategies to control coccidiosis of the domestic fowl. (C) 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.