189 research outputs found
Agroindustrialization through institutional innovation
Some small-holders are able to generate reliable and substantial income flows through small-scale dairy production for the local market; for others, a set of unique transactions costs hinders participation. Cooperative selling institutions are potential catalysts for mitigating these costs, stimulating entry into the market, and precipitating growth in rural communities. Trends in cooperative organization in East-African dairy are evaluated. Empirical work focuses on alternative techniques for effecting participation among a representative sample of peri-urban milk producers in the Ethiopian highlands. The techniques considered are a modern production practice (cross-bred cow use), a traditional production practice (indigenous-cow use), three intellectual-capital-forming variables (experience, education, extension), and the provision of infrastructure (as measured by time to transport milk to market). A Tobit analysis of marketable surplus generates precise estimates of non-participants' ‘distances' to market and their reservation levels of the covariates—measures of the inputs necessary to sustain and enhance the market. Policy implications focus on the availability of cross-bred stock and the level of market infrastructure, both of which have marked effects on participation, the velocity of transactions in the local community and, inevitably, the social returns to agroindustrialization.Dairy farming Ethiopia. ,Collective farms Ethiopia. ,
Detection of quantitative trait loci for locomotion and osteochondrosis-related traits in Large White x Meishan pigs.
The ultrasonic machining of silicon carbide / alumina composites.
Silicon carbide fibre reinforced alumina is a ceramic composite which was developed in conjunction with the Rolls-Royce Aerospace Group. The material is intended for use in the latest generation of jet engines, specifically for high temperature applications such as flame holders, combustor barrel segments and turbine blade tip seals. The material in question has properties which have been engineered by optimizing fibre volume fractions, weaves and fibre interface materials to meet the following main requirements : high thermal resistance, high thermal shock resistance and low density.Components intended for manufacture using this material will use the "direct metal oxidation" (DIMOX) method. This process involves manufacturing a near net shape component from the woven fibre matting, and infiltrating the matting with the alumina matrix material. Some of the components outlined require high tolerance features to be included in their design. The combustor barrel segments for example require slots to be formed within them for sealing purposes, the dimensions of these features preclude their formation using DIMOX, and therefore require a secondary process to be performed. Conventional machining techniques such as drilling, turning and milling cannot be used because of the brittle nature of the material. Electrodischarge machining (E.D.M.) cannot be used since the material is an insulator. Electrochemical machining (E.C.M.) cannot be used since the material is chemically inert. One machining method which could be used is ultrasonic machining (U.S.M.).The research programme investigated the feasibility of using ultrasonic machining as a manufacturing method for this new fibre reinforced composite. Two variations of ultrasonic machining were used : ultrasonic drilling and ultrasonic milling. Factors such as dimensional accuracy, surface roughness and delamination effects were examined. Previously performed ultrasonic machining experimental programmes were reviewed, as well as process models which have been developed. The process models were found to contain empirical constants which usually require specific material data for their calculation.Since a limited amount of the composite was available, and ultrasonic machining has many process variables, a Taguchi factorial experiment was conducted in order to ascertain the most relevant factors in machining. A full factorial experiment was then performed using the relevant factors. Techniques used in the research included both optical and scanning electron microscopy, surface roughness analysis, x-ray analysis and finite element stress analysis. A full set of machining data was obtained including relationships between the factors examined and both material removal rates, and surface roughness values. An attempt was made to explain these findings by examining established brittle fracture mechanisms. These established mechanisms did not seem to apply entirely to this material, an alternative method of material removal is therefore proposed. It is hoped that the data obtained from this research programme may contribute to the development of a more realistic mathematical model
The ultrasonic machining of silicon carbide / alumina composites.
Silicon carbide fibre reinforced alumina is a ceramic composite which was developed in conjunction with the Rolls-Royce Aerospace Group. The material is intended for use in the latest generation of jet engines, specifically for high temperature applications such as flame holders, combustor barrel segments and turbine blade tip seals. The material in question has properties which have been engineered by optimizing fibre volume fractions, weaves and fibre interface materials to meet the following main requirements : high thermal resistance, high thermal shock resistance and low density.Components intended for manufacture using this material will use the "direct metal oxidation" (DIMOX) method. This process involves manufacturing a near net shape component from the woven fibre matting, and infiltrating the matting with the alumina matrix material. Some of the components outlined require high tolerance features to be included in their design. The combustor barrel segments for example require slots to be formed within them for sealing purposes, the dimensions of these features preclude their formation using DIMOX, and therefore require a secondary process to be performed. Conventional machining techniques such as drilling, turning and milling cannot be used because of the brittle nature of the material. Electrodischarge machining (E.D.M.) cannot be used since the material is an insulator. Electrochemical machining (E.C.M.) cannot be used since the material is chemically inert. One machining method which could be used is ultrasonic machining (U.S.M.).The research programme investigated the feasibility of using ultrasonic machining as a manufacturing method for this new fibre reinforced composite. Two variations of ultrasonic machining were used : ultrasonic drilling and ultrasonic milling. Factors such as dimensional accuracy, surface roughness and delamination effects were examined. Previously performed ultrasonic machining experimental programmes were reviewed, as well as process models which have been developed. The process models were found to contain empirical constants which usually require specific material data for their calculation.Since a limited amount of the composite was available, and ultrasonic machining has many process variables, a Taguchi factorial experiment was conducted in order to ascertain the most relevant factors in machining. A full factorial experiment was then performed using the relevant factors. Techniques used in the research included both optical and scanning electron microscopy, surface roughness analysis, x-ray analysis and finite element stress analysis. A full set of machining data was obtained including relationships between the factors examined and both material removal rates, and surface roughness values. An attempt was made to explain these findings by examining established brittle fracture mechanisms. These established mechanisms did not seem to apply entirely to this material, an alternative method of material removal is therefore proposed. It is hoped that the data obtained from this research programme may contribute to the development of a more realistic mathematical model
Agroindustrialization Through Institutional Innovation: Transactions Costs, Cooperatives and Milk-Market Development in the Ethopian Highlands
Some small-holders are able to generate reliable and substantial income flows through small-scale dairy production for the local market; for others, a set of unique transactions costs hinders participation. Cooperative selling institutions are potential catalysts for mitigating these costs, stimulating entry into the market, and precipitating growth in rural communities. Trends in cooperative organization in East-African dairy are evaluated. Empirical work focuses on alternative techniques for effecting participation among a representative sample of periurban milk producers in the Ethiopian highlands. The techniques considered are a modern production practice (cross-bred cow use), a traditional production practice (indigenous-cow use), three intellectual-capital-forming variables (experience, education, extension), and the provision of infrastructure (as measured by time to transport milk to market). A Tobit analysis of marketable surplus generates precise estimates of non-participants’ ‘distances’ to market and their reservation levels of the covariates—measures of the inputs necessary to sustain and enhance the market. Policy implications focus on the availability of cross-bred stock and the level of market infrastructure, both of which have marked effects on participation, the velocity of transactions in the local community and, inevitably, the social returns to agroindustrialization
A systematic comparison of all mutations in hereditary sensory neuropathy type I (HSAN I) reveals that the G387A mutation is not disease associated
Hereditary sensory neuropathy type 1 (HSAN I) is an autosomal dominant inherited neurodegenerative disorder of the peripheral nervous system associated with mutations in the SPTLC1 subunit of the serine palmitoyltransferase (SPT). Four missense mutations (C133W, C133Y, V144D and G387A) in SPTLC1 were reported to cause HSAN I. SPT catalyses the condensation of Serine and Palmitoyl-CoA, which is the first and rate-limiting step in the de novo synthesis of ceramides. Earlier studies showed that C133W and C133Y mutants have a reduced activity, whereas the impact of the V144D and G387A mutations on the human enzyme was not tested yet. In this paper, we show that none of the HSAN I mutations interferes with SPT complex formation. We demonstrate that also V144D has a reduced SPT activity, however to a lower extent than C133W and C133Y. In contrast, the G387A mutation showed no influence on SPT activity. Furthermore, the growth phenotype of LY-B cells—a SPTLC1 deficient CHO cell line—could be reversed by expressing either the wild-type SPTLC1 or the G387A mutant, but not the C133W mutant. This indicates that the G387A mutation is most likely not directly associated with HSAN I. These findings were genetically confirmed by the identification of a nuclear HSAN family which showed segregation of the G387A variant as a non-synonymous SN
Способы перевода аббревиатур и сокращений в области компьютерных технологий (на примере русского и немецкого языков)
Выпускная квалификационная работа 75 с., 2 главы, 42 источника.
Предмет исследования: способы перевода аббревиатур и сокращений в области компьютерных технологий с немецкого языка на русский язык.
Объектом исследования: аббревиатуры и сокращения, относящиеся к области компьютерных технологий.
Цель работы: выявить эффективные способы перевода аббревиатур и сокращений в области компьютерных технологий с немецкого языка на русский.
Результаты исследования: были сформулированы особенности перевода аббревиатур и сокращений в области компьютерных технологий
Степень внедрения/апробация работы: Было опубликовано две статьи
Область применения: лингвистика, языкознание, переводоведение.Graduation thesis: 75 pg., 2 chapters, 42 resources.
Subject of research: translation methods of acronyms and reductions in the field of computer technology from German into Russian.
Object of research: Acronyms and reductions in the field of computer technology.
Purpose of research: : to identify the translation methods of acronyms and reductions in the field of computer technology from German into Russian.
Results of research: The features of the translation of acronyms and reductions in the area of computer technology has been revealed.
Degree of implementation /work approbation: two articles were published.
Field of application: Linguistic, theory of translatio
The Gly2019Ser mutation in LRRK2 is not fully penetrant in familial Parkinson\u27s disease: The GenePD study
Missense mutations in the copper transporter gene ATP7A cause X-Linked distal hereditary motor neuropathy
Distal hereditary motor neuropathies comprise a clinically and genetically heterogeneous group of disorders. We recently mapped an X-linked form of this condition to chromosome Xq13.1-q21 in two large unrelated families. The region of genetic linkage included ATP7A, which encodes a copper-transporting P-type ATPase mutated in patients with Menkes disease, a severe infantile-onset neurodegenerative condition. We identified two unique ATP7A missense mutations (p.P1386S and p.T994I) in males with distal motor neuropathy in two families. These molecular alterations impact highly conserved amino acids in the carboxyl half of ATP7A and do not directly involve the copper transporter's known critical functional domains. Studies of p.P1386S revealed normal ATP7A mRNA and protein levels, a defect in ATP7A trafficking, and partial rescue of a S. cerevisiae copper transport knockout. Although ATP7A mutations are typically associated with severe Menkes disease or its milder allelic variant, occipital horn syndrome, we demonstrate here that certain missense mutations at this locus can cause a syndrome restricted to progressive distal motor neuropathy without overt signs of systemic copper deficiency. This previously unrecognized genotype-phenotype correlation suggests an important role of the ATP7A copper transporter in motor-neuron maintenance and function
The Gly2019Ser mutation in LRRK2 is not fully penetrant in familial Parkinson's disease: the GenePD study
<p>Abstract</p> <p>Background</p> <p>We report age-dependent penetrance estimates for leucine-rich repeat kinase 2 (<it>LRRK2</it>)-related Parkinson's disease (PD) in a large sample of familial PD. The most frequently seen <it>LRRK2 </it>mutation, Gly2019Ser (G2019S), is associated with approximately 5 to 6% of familial PD cases and 1 to 2% of idiopathic cases, making it the most common known genetic cause of PD. Studies of the penetrance of <it>LRRK2 </it>mutations have produced a wide range of estimates, possibly due to differences in study design and recruitment, including in particular differences between samples of familial PD versus sporadic PD.</p> <p>Methods</p> <p>A sample, including 903 affected and 58 unaffected members from 509 families ascertained for having two or more PD-affected members, 126 randomly ascertained PD patients and 197 controls, was screened for five different <it>LRRK2 </it>mutations. Penetrance was estimated in families of <it>LRRK2 </it>carriers with consideration of the inherent bias towards increased penetrance in a familial sample.</p> <p>Results</p> <p>Thirty-one out of 509 families with multiple cases of PD (6.1%) were found to have 58 <it>LRRK2 </it>mutation carriers (6.4%). Twenty-nine of the 31 families had G2019S mutations while two had R1441C mutations. No mutations were identified among controls or unaffected relatives of PD cases. Nine PD-affected relatives of G2019S carriers did not carry the <it>LRRK2 </it>mutation themselves. At the maximum observed age range of 90 to 94 years, the unbiased estimated penetrance was 67% for G2019S families, compared with a baseline PD risk of 17% seen in the non-<it>LRRK2</it>-related PD families.</p> <p>Conclusion</p> <p>Lifetime penetrance of <it>LRRK2 </it>estimated in the unascertained relatives of multiplex PD families is greater than that reported in studies of sporadically ascertained <it>LRRK2 </it>cases, suggesting that inherited susceptibility factors may modify the penetrance of <it>LRRK2 </it>mutations. In addition, the presence of nine PD phenocopies in the <it>LRRK2 </it>families suggests that these susceptibility factors may also increase the risk of non-<it>LRRK2</it>-related PD. No differences in penetrance were found between men and women, suggesting that the factors that influence penetrance for <it>LRRK2 </it>carriers are independent of the factors which increase PD prevalence in men.</p
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