867 resultados para key factors
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We have investigated the influence of electrode material and crystallographic structure on electron transfer and biofilm formation of Geobacter sulfurreducens. Single-crystal gold - Au(110), Au(111), Au(210) - and platinum - Pt(100), Pt(110), Pt(111), Pt(210) - electrodes were tested and compared to graphite rods. G. sulfurreducens electrochemically interacts with all these materials with different attachment kinetics and final current production, although redox species involved in the electron transfer to the anode are virtually the same in all cases. Initial bacterial colonization was fastest on graphite up to the monolayer level, whereas gold electrodes led to higher final current densities. Crystal geometry showed to have an important influence, with Au(210) sustaining a current density of up to 1442 (± 101) μA cm- 2 at the steady state, over Au(111) with 961 (± 94) μA cm- 2 and Au(110) with 944 (± 89) μA cm- 2. On the other hand, the platinum electrodes displayed the lowest performances, including Pt(210). Our results indicate that both crystal geometry and electrode material are key parameters for the efficient interaction of bacteria with the substrate and should be considered for the design of novel materials and microbial devices to optimize energy production.
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Translators wishing to work on translating specialised texts are traditionally recommended to spend much time and effort acquiring specialist knowledge of the domain involved, and for some areas of specialised activity, this is clearly essential. For other types of translation-based, domain-specific of communication, however, it is possible to develop a systematic approach to the task which will allow for the production of target texts which are adequate for purpose, in a range of specialised domains, without necessarily having formal qualifications in those areas. For Esselink (2000) translation agencies, and individual clients, would tend to prefer a subject expert who also happens to have competence in one or more languages over a trained translator with a high degree of translation competence, including the ability to deal with specialised translation tasks. The problem, for the would-be translator, is persuading prospective clients that he or she is capable of this. This paper will offer an overview of the principles used to design training intended to teach trainee translators how to use a systematic approach to specialised translation, in order to extend the range of areas in which they can tackle translation, without compromising quality or reliability. This approach will be described within the context of the functionalist approach developed in particular by Reiss and Vermeer (1984), Nord (1991, 1997) inter alia.
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Russian e-commerce has drawn a lot of attention in academic publications as well as in public media lately. The market is growing with a speed of rocket offering companies enormous business opportunities. However, combination of Russian culture, consumer online purchasing and decision-making process forms a subject yet completely unknown. From international online business perspective it is vital for companies to know how a culture affects consumer’s purchase decision and what are the key elements that need to be modified in order to successfully expand online operations to Russian market. Here, the main purpose is to define the key factors affecting Russian consumer’s online purchase intention. In order to answer the main research question, firstly the role of culture in purchase intention context is researched. Secondly, focus is drawn to the factors that affect online purchase intention. Lastly, it is researched how Russian culture is affecting e-commerce attributes modification. The objective is not only to expand the theoretical understanding of the subject but also to provide companies with a clear vision on how the online operations should be conducted in Russian online market. Ranganathan’s and Jha’s conceptual framework was chosen as a ground theory in this study. Here, three main categories Computer Self-Efficacy and Past Online Experience, Website Quality and Costumer Concerns form basis for the study. Various articles and academic literature supplemented this theoretical approach. Qualitative research method was adapted and the study was conducted through five expert interviews. As a conclusion it can be stated that culture forms a ground for entire purchase decision-making process in online context. Results from the interviews were grouped according to main three theoretic categories and placed with Ranganathan’s and Jha’s original framework. This formed a new theoretical framework that defines diverse factors affecting specifically Russian consumer’s online purchase intention. This study suggests that following factors need to be taking into serious consideration in Russian online context: photography style, detailed product and company information, colors, language, product variety, reviews, recommendations, strong social media presence, fast check out and minimalistic order information, counterfeit fear, cash on delivery payment, training and guidance, extensive customer service, consumers’ insecurity, inexperience, high interest for technology and their individualistic personality.
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The Tully Sugar Mill has collected information about sugarcane supplied for crushing from every block in the mill district from 1970 to 1999. Data from 1988 to 1999 were analysed to understand the extent of the variation in cane yield per hectare and commercial cane sugar in the Tully mill area. The key factors influencing the variation in cane yield and commercial cane sugar in this commercial environment were identified and the variance components computed using a restricted maximum likelihood methodology. Cane yield was predominantly influenced by the year in which it was harvested, the month when the crop was ratooned (month of harvest in the previous year) and the farm of origin. These variables were relatively more important than variety, age of crop or crop class (plant crop, first ratoon through to fourth or older ratoons) and fallowing practice (fallow or ploughout-replant). The month-of-ratooning effect was relatively stable from year-to-year. Commercial cane sugar was influenced by the year of harvest, the month of harvest and their interaction, in that the influence of the month of harvest varied from year to year. Variety and farm differences were also significant but accounted for a much lower portion of the variation in commercial cane sugar. An empirical model was constructed from the key factors that influenced commercial cane sugar and cane yield to quantify their combined influence on sugar yield (t/ha). This may be used to assist mill personnel to predict their activities more accurately, for example to calculate the impact of a late finish to the current harvest season on the following year's crop.
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Enhanced biological phosphorus removal (EBPR) is the most economic and sustainable option used in wastewater treatment plants (WWTPs) for phosphorus removal. In this process it is important to control the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), since EBPR deterioration or failure can be related with the proliferation of GAOs over PAOs. This thesis is focused on the effect of operational conditions (volatile fatty acid (VFA) composition, dissolved oxygen (DO) concentration and organic carbon loading) on PAO and GAO metabolism. The knowledge about the effect of these operational conditions on EBPR metabolism is very important, since they represent key factors that impact WWTPs performance and sustainability. Substrate competition between the anaerobic uptake of acetate and propionate (the main VFAs present in WWTPs) was shown in this work to be a relevant factor affecting PAO metabolism, and a metabolic model was developed that successfully describes this effect. Interestingly, the aerobic metabolism of PAOs was not affected by different VFA compositions, since the aerobic kinetic parameters for phosphorus uptake, polyhydroxyalkanoates (PHAs) degradation and glycogen production were relatively independent of acetate or propionate concentration. This is very relevant for WWTPs, since it will simplify the calibration procedure for metabolic models, facilitating their use for full-scale systems. The DO concentration and aerobic hydraulic retention time (HRT) affected the PAO-GAO competition, where low DO levels or lower aerobic HRT was more favourable for PAOs than GAOs. Indeed, the oxygen affinity coefficient was significantly higher for GAOs than PAOs, showing that PAOs were far superior at scavenging for the often limited oxygen levels in WWTPs. The operation of WWTPs with low aeration is of high importance for full-scale systems, since it decreases the energetic costs and can potentially improve WWTP sustainability. Extended periods of low organic carbon load, which are the most common conditions that exist in full-scale WWTPs, also had an impact on PAO and GAO activity. GAOs exhibited a substantially higher biomass decay rate as compared to PAOs under these conditions, which revealed a higher survival capacity for PAOs, representing an advantage for PAOs in EBPR processes. This superior survival capacity of PAOs under conditions more closely resembling a full-scale environment was linked with their ability to maintain a residual level of PHA reserves for longer than GAOs, providing them with an effective energy source for aerobic maintenance processes. Overall, this work shows that each of these key operational conditions play an important role in the PAO-GAO competition and should be considered in WWTP models in order to improve EBPR processes.
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L’estudi realitzat ha abordat quines són les competències i els factors clau que estudiants universitaris d’origen immigrant consideren que han estat claus per arribar a la universitat, assolint així l’èxit educatiu. S’han escollit estudiants que haguessin fet l’escolaritat obligatòria total o parcialment a Catalunya.Per dur a terme la recerca s’ha treballat amb relats de vida (un total de 13 escrits) i narracions audiovisuals (amb un total de 4 produccions), essent finalment 17 les evidències vàlides. Finalment, s’ha elaborat, administrat i processat un qüestionari d’opinió que s’ha remès a 2472 estudiants de la Universitat de Barcelona, dels quals hem aconseguit 128 respostes considerades vàlides. Els relats s’han analitzat amb un procediment inductiu, procedint a una lectura exhaustiva de les paraules dels participants i anant identificant quines són les competències i els factors clau que ells consideraven que els havien ajudat a arribar a la universitat o que, tot i no ser ells conscients, nosaltres identificàvem com a tals. Pel que fa a les narracions audiovisuals, es va dur a terme una anàlisi tant del contingut, tenint com a referència els resultats obtinguts als relats escrits, com d’aspectes més tècnics, centrats en la imatge i el so. Per acabar, els qüestionaris s’han analitzat a partir de processos bàsics d’estadística descriptiva. Pel que fa als resultats obtinguts, respecte a l’eix de competències, la més destacada és la d’autonomia i iniciativa personals, lligada a la responsabilitat i autoexigència. Respecte a l’eix d’èxit educatiu, destaca el paper del professorat, tant pel suport que els ofereixen com per les expectatives que dipositen en ells. I, per acabar, respecte a l’eix d’inclusió social, els aspectes que l’afavoreixen es centren sobretot en el recolzament de la família, en l’entorn més immediat i en el fet d’entendre la possibilitat de viure amb altres cultures com un enriquiment.
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Comparative national management accounting is the least developed aspect in the field of international accounting. Only during the second half of the 1990's some comparisons of national managementaccounting practice have appeared published but only at theregional level. In this paper a range of factors that give rise to variations in national management accounting practice are postulated. We support this list with examples from a range of analyses of national management accounting practices, drawing particularly on the work of Lizcano (1996) and Bhimani (1996).Finally, twelve key factors are identified as influencing an individual country's approach to management accounting.
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1. Species distribution models are increasingly used to address conservation questions, so their predictive capacity requires careful evaluation. Previous studies have shown how individual factors used in model construction can affect prediction. Although some factors probably have negligible effects compared to others, their relative effects are largely unknown. 2. We introduce a general "virtual ecologist" framework to study the relative importance of factors involved in the construction of species distribution models. 3. We illustrate the framework by examining the relative importance of five key factors-a missing covariate, spatial autocorrelation due to a dispersal process in presences/absences, sample size, sampling design and modeling technique-in a real study framework based on plants in a mountain landscape at regional scale, and show that, for the parameter values considered here, most of the variation in prediction accuracy is due to sample size and modeling technique. Contrary to repeatedly reported concerns, spatial autocorrelation has only comparatively small effects. 4. This study shows the importance of using a nested statistical framework to evaluate the relative effects of factors that may affect species distribution models.
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In the assessment of social impact caused by meteorological events, factors of different natures need to be considered. Not only does hazard itself determine the impact that a severe weather event has on society, but also other features related to vulnerability and exposure. The requests of data related to insurance claims received in meteorological services proved to be a good indicator of the social impact that a weather event causes, according to studies carried out by the Social Impact Research Group, created within the framework of the MEDEX project. Taking these requests as proxy data, diverse aspects connected to the impact of heavy rain events have been studied. The rainfall intensity, in conjunction with the population density, has established itself as one of the key factors in social impact studies. One of the conclusions we obtained is that various thresholds of rainfall should be applied for areas of varying populations. In this study, the role of rainfall intensity has been analysed for a highly populated urban area like Barcelona. A period without significant population changes has been selected for the study to minimise the effects linked to vulnerability and exposure modifications. First, correlations between rainfall recorded in different time intervals and requests were carried out. Afterwards, a method to include the intensity factor in the social impact index was suggested based on return periods given by intensity duration frequency (IDF) curves.
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Open source and open source software development have been interesting phenomena during the past decade. Traditional business models do not apply with open source, where the actual product is free. However, it is possible to make business with open source, even successfully, but the question is: how? The aim of this study is to find the key factors of successfully making business out of commercial open source software development. The task is achieved by finding the factors that influence open source projects, finding the relation between those factors, and find out why some factors explain the success more than others. The literature review concentrates first on background of open innovation, open source and open source software. Then business models, critical success factors and success measures are examined. Based on existing literature a framework was created. The framework contains categorized success factors that influence software projects in general as well as open source software projects. The main categories of success factors in software business are divided into community management, technology management, project management and market management. In order to find out which of the factors based on the existing literature are the most critical, empirical research was done by conducting unstructured personal interviews. The main finding based on the interviews is that the critical success factors in open source software business do not differ from those in traditional software business or in fact from those in any other business. Some factors in the framework came out in the interviews that can be considered as key factors: establishing and communicating hierarchy (community management), localization (technology management), good license know-how and IPR management (project management), and effective market management (market management). The critical success factors according to the interviewees are not listed in the framework: low price, good product and good business model development.
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Cooperative caching in mobile ad hoc networks aims at improving the efficiency of information access by reducing access latency and bandwidth usage. Cache replacement policy plays a vital role in improving the performance of a cache in a mobile node since it has limited memory. In this paper we propose a new key based cache replacement policy called E-LRU for cooperative caching in ad hoc networks. The proposed scheme for replacement considers the time interval between the recent references, size and consistency as key factors for replacement. Simulation study shows that the proposed replacement policy can significantly improve the cache performance in terms of cache hit ratio and query delay
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This paper presents the results of (a) On-farm trials (eight) over a two-year period designed to test the effectiveness of leguminous cover crops in terms of increasing maize yields in Igalaland, Nigeria. (b) A survey designed to monitor the extent of, and reasons behind, adoption of the leguminous cover crop technology in subsequent years by farmers involved, to varying degrees, in the trial programme. particular emphasis was placed on comparing adoption of leguminous cover crops with that of new crop varieties released by a non-governmental organization in the same area since the mid 1980s. While the leguminous cover crop technology boosted maize grain yields by 127 to 136% above an untreated control yield of between 141 and 171 kg ha(-1), the adoption rate (number of farmers adopting) was only 18%. By way of contrast, new crop varieties had a highly variable benefit in terms of yield advantage over local varieties, with the best average increase of around 20%. Adoption rates for new crop varieties, assessed as both the number of farmers growing the varieties and the number of plots planted to the varieties, were 40% on average. The paper discusses some key factors influencing adoption of the leguminous cover crop technology, including seed availability. Implications of these results for a local non-governmental organization, the Diocesan Development Services, concerned with promoting the leguminous cover crop technology are also discussed.
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The aim of this article was to determine which aspects of Huntington's disease (HD) are most important with regard to the health-related quality of life (HrQOL) of patients with this neurodegenerative disease. Seventy patients with HD participated in the study. Assessment comprised the Unified Huntington's Disease Rating Scale (UHDRS) motor, cognitive and functional capacity sections, and the Beck Depression inventory. Mental and physical HrQOL were assessed using summary scores of the SF-36. Multiple regression analyses showed that functional capacity and depressive mood were significantly associated with HrQOL, in that greater impairments in HrQOL were associated with higher levels of depressive mood and lower functional capacity. Motor symptoms and cognitive function were not found to be as closely linked with HrQOL. Therefore, it can be concluded that, depressive mood and greater functional incapacity are key factors in HrQOL for people with HD, and further longitudinal investigation will be useful to determine their utility as specific targets in intervention studies aimed at improving patient HrQOL, or whether other mediating variables. As these two factors had a similar association with the mental and physical summary scores of the SF-36, this generic HrQOL measure did not adequately capture and distinguish the true mental and physical health-related HrQOL in HD.