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Phylogenetic relationships and call structure in four African bufonid species
M.I. Cherry,W.S. Grant
African Zoology , 2012,
Abstract: ENGLISH ABSTRACT: Four species of toads of the genus Bufo. comprising three species endemic to southern Africa and one closely-related species, were examined electrophoretically to infer their phylogenetic relationships. The evolution of advertisement call structure in these species is discussed in relation to this phylogeny. Bufo rangeri and B. gutturalis, two species with very different call structures, are sister taxa. Two pairs of species with very similar call structures, B. pardalis and B. gutturalis, and B. rangeri and B. angusticeps, were only distantly related. Our results suggest that call parameters are poor characters to use in inferring phylogenies among congeneric species, probably because of selection for optimal audibility in different habitats, and because of the role that they play in premating isolation. The phylogeny derived from allozyme data agrees with evidence on albumin immunological distance, karyotype and morphology. *********** AFRIKAANSE OPSOMMING: Vier spesies skurwepaddas van die genus Buto, bestaande uit drie wat endemies is in Suid-Afrika en een nou-verwante spesie, is elektroforeties ondersoek om hulle filogenetiese verwantskap af te lei. Die evolusie van die struktuur van die bekendstellingsroep by hierdie spesie word met betrekking tot hierdie filogenie bespreek. Buto rangeri en B. gutturalis, twee spesies met baie verskillende roepstrukture, is suster taksa. Twee pare van spesies met baie ooreenstemmende roepstrukture, B. pardalis en B. gutturalis, en B. rangeri en B. angusticeps, was slegs ver langs verwant. Ons resultate dui daarop dat roep-parameters swak kenmerke is om te gebruik by die aflei van filogenie by verwante spesies, waarskynlik as gevolg van seleksie wat plaasvind vir optimale hoorbaarheid in verskillende habitatte, sowel as die rol wat hulle speel by die pre-paringsisolasie. Die filogenie wat van allosiemdata afgelei is, stem ooreen met getuienis oor albumien immunologiese afstand, kariotipe en morfologie .
Anuran distribution, diversity and conservation in South Africa, Lesotho and Swaziland
D.R. Drinkrow,M.I. Cherry
African Zoology , 2011,
Abstract: The distributions of 96 anuran species in South Africa were mapped using published locality records, and the collections of the South African and Port Elizabeth museums. Centres of richness, endemism and Red Data Book (ROB) richness were identified, and compared with currently protected areas, using a geographical information system (GIS). Maputaland and the Kwazulu/Natal coast were identified as centres of species richness. Endemic 'hotspots' occur in the vicinity of Pietermaritzburg, Durban and the fynbos region of the Western Cape. The Western Cape was also identified as a centre of ROB species richness. A large portion (95,8%) of South African anuran species are found in protected areas. The effective long-term viability of populations of many of these species within these areas, must be assessed. Currently four South African frog species are not found within protected areas. The Karoo biomes were identified as being under-represented, both in the species database and in the proportion of conserved areas. While a large proportion of the fynbos biome is contained in reserve areas, the low-lying fynbos habitats have almost disappeared as a result of urbanization and agriculture. Remnants of the sandy coastal fynbos and renosterveld veld types require urgent conservation. Several areas in the Western and Eastern Cape were identified as requiring additional research and conservation measures. A GIS proves a useful tool in the analysis of species distributions and the prioritization of areas and species for conservation. The importance of accurate collection data, for incorporation into species databases, and the regular publication of reserve species lists is emphasized.
Territoriality and breeding success in Gurney’s sugarbird, Promerops gurneyi
K.M. Calf,C.T. Downs,M.I. Cherry
African Zoology , 2011,
Abstract: Territory size and quality were determined for Gurney’s sugarbirds in Qwaqwa National Park,northeastern Free State, South Africa. Changes in territory size of Gurney’s sugarbirds during the six-month season reflect increases in numbers of territorial birds and inflorescences at mid breeding season, and declines in both at the end of the breeding season. Only 25 %of pairs laid eggs, and mating appears to have been constrained by low nectar and arthropod energy availability, and the costs associated with the defence of large territories. Reproductive success was directly related to arthropod availability on territories, with pairs not even appearing to attempt breeding if this is low. Males with longer tails and wider sixth primary feather bulges defended larger territories, indicating that ornament size and displays of Gurney’s sugarbirds may be important in territory maintenance.
La gestión del proceso de convocatoria de plazas de formación médica especializada
Alonso,M.I.;
Gaceta Sanitaria , 2003, DOI: 10.1590/S0213-91112003000400006
Abstract: objective: currently there is a large imbalance between supply and demand for medical specialists in the spanish health system. the aim of this study was to demonstrate the possible effects of current policies of allocating vacancies for interns and residents as well as to describe several measures and alternative policies. methods: using the methodology of system dynamics, we designed a simulation model of the allocation process. based on the validated model, possible changes in the system through time in response to diverse allocation policies were simulated. specifically, changes in the accumulated number of graduates who over the years have remained without specialty, the number of unemployed specialists, and the imbalance between supply and demand in the period under consideration were observed. results: the results obtained from the simulation indicate that allocation policies such as the current one tends to reduce the accumulated number of graduates without specialty, due to the philosophy characterizing this policy, but that it considerably increases the number of unemployed specialists and aggravates the supply-demand imbalance. in the simulation, this tendency remained over time even though more restrictive measures in numerus clausus and retirement age were adopted. equally, a policy based on social needs and aware of delays in training would substantially contribute to eliminating unemployment among specialists and supply-demand imbalance over time. if such a policy were combined with the above-mentioned measures the results would be even better, more rapidly eliminating graduates without specialty, unemployed specialists, and supply-demand imbalances. conclusions: if the health administration continues with the current system of allocation of places, the present imbalance in supply and demand will become even worse. therefore, new and far-sighted measures and policies are required, as well as greater coordination between undergraduate and postgraduate
Somatic gene therapy for hypertension
Phillips, M.I.;
Brazilian Journal of Medical and Biological Research , 2000, DOI: 10.1590/S0100-879X2000000600013
Abstract: gene therapy for hypertension is needed for the next generation of antihypertensive drugs. current drugs, although effective, have poor compliance, are expensive and short-lasting (hours or one day). gene therapy offers a way to produce long-lasting antihypertensive effects (weeks, months or years). we are currently using two strategies: a) antisense oligodeoxynucleotides (as-odn) and b) antisense dna delivered in viral vectors to inhibit genes associated with vasoconstrictive properties. it is not necessary to know all the genes involved in hypertension, since many years of experience with drugs show which genes need to be controlled. as-odn are short, single-stranded dna that can be injected in naked form or in liposomes. as-odn, targeted to angiotensin type 1 receptors (at1-r), angiotensinogen (agt), angiotensin converting enzyme, and ?1-adrenergic receptors effectively reduce hypertension in rat models (shr, 2k-1c) and cold-induced hypertension. a single dose is effective up to one month when delivered with liposomes. no side effects or toxic effects have been detected, and repeated injections can be given. for the vector, adeno-associated virus (aav) is used with a construct to include a cmv promoter, antisense dna to agt or at1-r and a reporter gene. results in shr demonstrate reduction and slowing of development of hypertension, with a single dose administration. left ventricular hypertrophy is also reduced by aav-agt-as treatment. double transgenic mice (human renin plus human agt) with high angiotensin ii causing high blood pressure, treated with aav-at1-r-as, show a normalization of blood pressure for over six months with a single injection of vector. we conclude that odns will probably be developed first because they can be treated like drugs for the treatment of hypertension with long-term effects. viral vector delivery needs more engineering to be certain of its safety, but one day may be used for a very prolonged control of blood pressure.
Connections: can the 20th century coronary heart disease epidemic reveal something about the 1918 influenza lethality?
Azambuja, M.I;
Brazilian Journal of Medical and Biological Research , 2008, DOI: 10.1590/S0100-879X2006005000192
Abstract: this essay proposes that the ecologic association shown between the 20th century coronary heart disease epidemic and the 1918 influenza pandemic could shed light on the mechanism associated with the high lethality of the latter. it suggests that an autoimmune interference at the apob-ldl interface could explain both hypercholesterolemia and inflammation (through interference with the cellular metabolism of arachidonic acid). autoimmune inflammation, then, would explain the 1950s-60s acute coronary events (coronary thrombosis upon influenza re-infection) and the respiratory failure seen among young adults in 1918. this hypothesis also argues that the lethality of the 1918 pandemic may have not depended so much on the 1918 virus as on an immune vulnerability to it, possibly resulting from an earlier priming of cohorts born around 1890 by the 1890 influenza pandemic virus.
Attention Deficit Hyperactivity Disorder Intervention: Strategies & Counselling Tips for Primary School Teachers.
M.I Abikwi
Edo Journal of Counselling , 2009,
Abstract: This paper addresses attention deficit hyperactivity disorder intervention strategies for primary school teachers. Wrong labelling of children with attention deficit hyperactivity disorder has given rise to this paper. Hitherto not much attention has been given to the pupils who manifest symptoms of this chronic behavioural disorder even when they are going through difficulties in the learning process. The need for teachers’ intervention strategies has been extensively discussed in this paper with a view of developing an intervention programme in other to promote care and support for the pupils who manifest symptoms of ADHD. It is recommended among other things that teachers’ knowledge should be enhanced to equip them to enable them give care and support to ADHD pupils in the learning process and make referral when necessary. There is an urgent need to include in the curriculum of Guidance and Counselling in Nigeria institutions Attention Deficit Hyperactivity Disorder its symptoms and management strategies. Also Counselling units should be established in primary schools in line with the provisions in the National policy on Education this will reduce most of the problems ADHD pupils face during learning process.
The Main Methods of Information Memorizing
M.I. Us
Economics of Development , 2011,
Abstract: The theoretical and practical recommendationsto improve the mechanism for storing information through the application of basic techniques and methods of capturing information in memory are reviewed and analyzed.
La gestión del proceso de convocatoria de plazas de formación médica especializada
Alonso M.I.
Gaceta Sanitaria , 2003,
Abstract: Objetivo: Dado el actual desajuste existente entre oferta y demanda de médicos especialistas en el sistema sanitario espa ol, el objetivo de este trabajo es mostrar el impacto que puede tener sobre el sistema las actuales políticas de convocatoria de plazas de formación médica especializada -plazas MIR-, así como diversas medidas y políticas alternativas de control. Métodos: Con esta finalidad se procedió a elaborar un modelo de simulación del proceso de convocatoria de plazas empleando como metodología la dinámica de sistemas. A partir del modelo elaborado y validado, se procede a simular la posible evolución del sistema a lo largo del tiempo ante diversas políticas de convocatoria. En concreto, se observa la evolución de la bolsa histórica de licenciados sin especialidad, la bolsa de médicos especialistas y el gap, o desajuste, entre oferta y demanda, existente en el período de simulación considerado. Resultados: De los resultados obtenidos de la simulación se observa que una política de convocatoria como la actual tiende a reducir la bolsa histórica de licenciados sin especialidad, debido a la propia filosofía que caracteriza a la actual convocatoria, pero incrementa considerablemente la bolsa de médicos especialistas y agudiza el desequilibrio existente. Esta tendencia se mantiene a pesar de que se adopten en la simulación medidas más restrictivas en numerus clausus y edad de jubilación forzosa. Se observa igualmente cómo una política consciente de las necesidades sociales y de los retrasos formativos existentes en el proceso mejora de modo sustancial la evolución, eliminando con el tiempo la bolsa de médicos especialistas y el desequilibrio. Si a su vez se combina dicha política con las medidas anteriormente citadas, los resultados obtenidos son aún superiores, eliminando ambas bolsas y el desajuste existente con mayor rapidez. Conclusiones: Si la Administración Sanitaria continúa convocando plazas de especialización como hasta el presente se agudizarán los problemas de desequilibrio existentes. Por lo tanto, es preciso adoptar medidas y políticas más previsoras con visión a largo plazo, así como una mayor coordinación entre la formación pre y posgraduada.
Applying Quaternion Fourier Transforms for Enhancing Color Images
M.I. Khalil
International Journal of Image, Graphics and Signal Processing , 2012,
Abstract: The Fourier transforms play a critical role in a broad range of image processing applications, including enhancement, analysis, restoration, and compression. Until recently, it was common to use the conventional methods to deal with colored images. These methods are based on RGB decomposition of the colored image by separating it into three separate scalar images and computing the Fourier transforms of these images separately. The computing of the Hypercomplex 2D Fourier transform of a color image as a whole unit has only recently been realized. This paper is concerned with frequency domain noise reduction of color images using quaternion Fourier transforms. The approach is based on obtaining quaternion Fourier transform of the color image and applying the Gaussian filter to it in the frequency domain. The filtered image is then obtained by calculating the inverse quaternion Fourier transforms.
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