7,034 research outputs found
A potent sex attractant of the male tea tussock moth, Euproctis pseudoconspersa (Strand) (Lepidoptera; Lymantridae) in Taiwan: Field and EAG responses.
No full textAnálise do acoplamento pressão-velocidade nas equações de Navier-Stokes utilizando o método dos volumes finitos baseado em elementos e solução acoplada
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia Mecânica.Este trabalho tem como objetivo estudar os métodos FIELDS e Rhie-Chow para tratamento do acoplamento pressão-velocidade na solução das equações de Navier-Stokes e realizar sua implementação computacional. Estes métodos apresentam diferentes maneiras de introduzir a pressão na equação de conservação da massa para a solução acoplada da pressão e velocidade. Ambos se utilizam de técnicas baseadas em funções de interpolação, que são decorrentes das próprias equações de conservação da quantidade de movimento, de forma a estabelecer um forte acoplamento entre as variáveis das equações. A aplicação em malhas não-estruturadas é realizada através do método dos volumes finitos baseado em elementos. Com o simulador desenvolvido, os métodos FIELDS e Rhie-Chow são avaliados através da solução de problemas conhecidos na literatura. Primeiro, são realizadas avaliações individuais dos métodos quanto à sua estabilidade e consistência. Em seguida são traçados comparativos entre as soluções obtidas. São analisadas características como: qualidade das soluções, convergência, influência do passo de tempo, tempos de solução dos sistemas lineares e montagem da matriz de coeficientes. The main goal of this work is the study of the FIELDS and Rhie-Chow methods for treatment of the pressure-velocity coupling in the solution of the Navier-Stokes equations and develop their computational codes. These methods have different ways of introducing the pressure in the mass conservation equation when a coupled solution is sought. Both use techniques based on interpolation functions, which come from the momentum conservation equations, in a way that a strong coupling between the equations is established. The use on unstructured meshes is performed by the element based finite volume method. The FIELDS and Rhie-Chow methods are evaluated by solving well-known testing problems from the literature. First, they are individually evaluated based on their stability and robustness. Then, the solutions are compared and analyzed according to the following criteria: solution quality, convergence, time step influence, CPU time spent to solve linear systems and assembling the global coefficient matrix
Behaviour of buried pipelines subjected to external loading.
No full textThe research presented in this Thesis was carried out at the University of Sheffield under
the supervision of Dr I. C. Pyrah and Dr W. F. Anderson, and Mr G. Leach at British Gas
Engineering Research Station (ERS). The research was financially supported by a British
Gas Research Scholarship and by the Overseas Research Students Awards Scheme.
The Author would like to express his sincere gratitude to his supervisors for their invaluable
help, guidance and encouragement during the development of the research.
The Author is also grateful to Dr S. R. Mi for his interest and assistance throughout the
research. Special thanks also go to Dr S. J. Wheeler for his supervision during the first year
of the research and sound advice in the initial stage of the work.
The Author would like to express his gratitude to all members of the geotechnics group at
the University of Sheffield for the useful discussions and comments. Special thanks and
appreciation are extended to the staff at the ERS, particularly Mr E. Middleton for
providing the data of the field tests and constructive comments.
The laboratory tests were performed at ERS Soils Laboratory for which the Author is
thankful to the laboratory staff. The Author must also thank British Gas for providing the
computer hardware and software for performing the numerical analyses, and the printing
facilities to produce the Thesis. Thanks also go to Mr D. Reay and Mr B. Bellwood at the
Gas Research Centre of British Gas for ensuring continuous financial support throughout
the award period.
Finally, the Author wishes to thank his family and friends for their endless support and
encouragement throughout the period of study in the UK. Without them, this Thesis may
never have been completed
Chow motives associated to certain algebraic Hecke characters
No full textShimura and Taniyama proved that if USD A USD is a potentially CM abelian variety over a number field USD F USD with CM by a field USD K USD linearly disjoint from F, then there is an algebraic Hecke character USD \lambda _A USD of USD FK USD such that USD L(A/F,s)=L(\lambda _A,s) USD. We consider a certain converse to their result. Namely, let USD A USD be a potentially CM abelian variety appearing as a factor of the Jacobian of a curve of the form USD y^e=\gamma x^f+\delta USD. Fix positive integers USD a USD and USD n USD such that USD n/2 < a \leq n USD. Under mild conditions on USD e, f, \gamma , \delta USD, we construct a Chow motive USD M USD, defined over USD F=\mathbb{Q}(\gamma ,\delta )USD, such that USD L(M/F,s) USD and USD L(\lambda _A^a\overline {\lambda }_A^{n-a},s) USD have the same Euler factors outside finitely many primes
AN EXACT SOLUTION OF THE VIBRATIONAL MOTION OF A DISSOCIATIVE STATE.
No full text D.K. Bhattacharyya and L.-Y. Chow Chiu, J. Chem. Phys. 67, 5727 (1978).Author Institution: Department of Chemistry, Howard UniversityUsing to represent the potential function for a diatomic dissociative state, an exact vibrational wave function is obtained. Parameters and are to be determined from a known potential curve, and N are respectively the electronic and rotational quantum numbers and M is the reduced mass. The solution , is shown to become a rapidly converging power series of 1/kr in the region of large (kr), and a rapidly converging power series of kr in the region of small (kr). the two series overlap in the intermediate region. and are positive real numbers, and E is the energy above the dissociation limit . For , the wave function for the dissociative state of is computed to compare with WKB wave function in The calculation is extended to high N to determine the N-dependence of the life time of the state
A proposal to obtain a long quarterly chilean gdp series
No full textAn important limitation in order to specify and estimate a macroeconomic model that describes the Chilean economy resides in using variables with sufficient number of observations that allow for a reliable econometric estimation. Among these variables, the GDP constitutes a fundamental magnitude. Nevertheless, for this variable there is not quarterly information before 1980. This paper computes quarterly GDP series for the period 1966-1979 using the approach by Casals et al (2000). As result, the new series incorporates the cyclical dynamic in the quarterly series later to 1979 respecting, in addition, all the annual existing information before the above mentioned period
Ingredientes funcionales y efecto protector cardiovascular de aceites de semillas de calabaza
No full textThe objective of the present study was to evaluate the cardiovascular protective effect of Egyptian and European umpkin seed oil (PSO) in hypercholesterolemic rats. Tocopherols, fatty acids (FAs) and unsaponifiable matter (UNSAP) were assessed in both oils. The results showed that α-tocopherol was 108 and 273, γ-tocopherol was 3.95 and 0 and d-tocopherol was 0 and 1.58 mg·100 g-1 oil of the Egyptian and European, respectively. GLC analysis of FAs revealed the presence of linoleic acid as the major fatty acid in both oils. Feeding a hypercholesterolemic diet produced a significant increase in plasma total cholesterol (T-Ch), triglycerides (TGs), low density lipoprotein cholesterol, T-Ch/HDL-Ch, TGs/HDL-Ch and malondialdehyde and a significant reduction in high density lipoprotein cholesterol (HDL-Ch), vitamin E, and adiponectin. Rats fed on hypercholesterolemic diet with either oil showed a significant improvement in all biochemical parametersEl objetivo fue evaluar el efecto protector cardiovascular de aceites de semilla de calabaza (PSO) de variedades egipcia y europea en ratas con hipercolesterolemia. Se evaluó tocoferoles, ácidos grasos (FAs) y materia insaponificable (UNSAP) en ambos aceites. Los resultados mostraron valores de α-tocoferol de 108 y 273, γ-tocoferol 3,95 y 0 y δ-tocoferol de 0 y 1,58 mg·100 g-1 en las variedades egipcia y europea, respectivamente. El análisis por GLC de los ácidos grasos (FAS) mostró al linoleico como mayoritario en ambos aceites. La alimentación con una dieta hipercolesterolémica produjo en plasma un aumento significativo de colesterol total (T-Ch), triglicéridos (TG), colesterol en lipoproteínas de baja densidad, T-Ch/HDL-Ch, TGs/HDL- ch y malondialdehído y una reducción significativa en el colesterol de lipoproteínas de alta densidad (HDL-cH), vitamina E, y adiponectina. Las ratas alimentadas con una dieta hipercolesterolémica y con ambos aceites, mostraron mejoras significativas en todos los parámetros bioquímicos
Diagnostic and therapeutic evaluation of 111In-vinorelbine liposomes in a human colorectal carcinoma HT-29/luc-bearing animal model
No full textVitamin E reduces amyloidosis and improves cognitive function in Tg2576 mice following repetitive concussive brain injury
No full textTraumatic brain injury is a well-recognized environmental risk factor for developing Alzheimer's disease. Repetitive concussive brain injury (RCBI) exacerbates brain lipid peroxidation, accelerates amyloid (Abeta) formation and deposition, as well as cognitive impairments in Tg2576 mice. This study evaluated the effects of vitamin E on these four parameters in Tg2576 mice following RCBI. Eleven-month-old mice were randomized to receive either regular chow or chow-supplemented with vitamin E for 4 weeks, and subjected to RCBI (two injuries, 24 h apart) using a modified controlled cortical impact model of closed head injury. The same dietary regimens were maintained up to 8 weeks post-injury, when the animals were killed for biochemical and immunohistochemical analyses after behavioral evaluation. Vitamin E-treated animals showed a significant increase in brain vitamin E levels and a significant decrease in brain lipid peroxidation levels. After RBCI, compared with the group on regular chow, animals receiving vitamin E did not show the increase in Abeta peptides, and had a significant attenuation of learning deficits. This study suggests that the exacerbation of brain oxidative stress following RCBI plays a mechanistic role in accelerating Abeta accumulation and behavioral impairments in the Tg2576 mice
Making people work longer – What is the impact on the medical workforce?
No full textThe current work examined the sociological impact of increasing the State Pension Age on the medical workforce in the United Kingdom. This project mainly focussed on Trained Hospital Doctors in England due to the extremely large data and time constraint. The government of the United Kingdom had carried forward the increment of the State Pension Age to 67 between year 2026 and 2028, which was earlier planned to be implemented between year 2034 and 2036. System dynamics modelling was chosen to be the most appropriate approach for this project. The project applied the qualitative and quantitative modelling. Qualitative modelling was done by constructing a causal loop diagram. Quantitative modelling consisted of two stages. The first stage was the development of retirement profile tool to calculate the retirement rate at each age group. Secondly, a system dynamics simulation model was developed using Vensim DSS to forecast the supply and demand of the English medical workforce up to year 2040 by generating plausible scenarios. Plausible scenarios were developed based on the retirement behavior of the medical workforce in response to the reformation of the State Pension age. The results showed the size of Trained Hospital Doctor workforce annually and evaluated the proposed reformation of the State Pension age
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