1,034 research outputs found

    Software Process Improvement and Human Judgement Heuristics

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    This paper exemplifies how better knowledge about human judgement strategies known as heuristics can be used to improve software processes, especially estimation and prediction processes. Human judgement heuristics work well when they exploit a fit between their structure and the structure of the environment in which they are used. This use of environmental fit may lead to amazingly good judgements based on little information and simple computations compared with more formal approaches. Sometimes, however, the heuristics may lead to poor judgements. Knowing more about the strengths and weaknesses of human judgement heuristics we may be able to (1) know when to use formal process improvement approaches and when to use less expensive expert judgements, (2) support the experts in situations where the experts’ judgements strategies are known to perform poorly, (3) improve the formal processes with elements from the experts’ strategies, and (4) train the experts in the use of more optimal judgement strategies. A small-scale experiment was carried out to evaluate the use of the representativeness heuristic in a software development effort estimation context. The results indicate that the actual use of the representativeness heuristic differed very much among the estimators and was not always based on an awareness of fit between the structure of the heuristic and the structure of the environment. Estimation strategies only appropriate in low uncertainty development environments were used in high uncertainty environments. A possible consequence of this finding is that expert estimators should be trained in assessing how well previous software projects predict new software projects, i.e., the uncertainty of the environment, and how this uncertainty should impact the estimation strategy

    Left atrial function and remodelling in aortic stenosis.

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    AIMS: The present study sought to determine the relationship between left atrial (LA) volume (structural changes) and LA function as assessed by strain rate imaging in patients with aortic stenosis (AS). METHODS AND RESULTS: The study consisted of a total of 64 consecutive patients with severe AS (<1 cm²) and 20 healthy control subjects. The phasic LA volumes and function (tissue Doppler-derived strain) were assessed in all patients. As compared with healthy controls, all strain-derived parameters of LA function were reduced in patients with AS. Conversely, only indexed LA passive volume (increased) (7.6 ± 3.8 vs. 10.5 ± 5.1 ml/m², P= 0.02) and LA active fraction (decreased) (43 ± 6.7 vs. 31 ± 13.3%, P< 0.001) (volume-based parameters) were significantly different between AS and controls. In AS, LA volume-derived function parameters were poorly correlated with LA strain parameters. In fact, by multivariable analysis, no LA phasic strain parameters emerged as independently associated with LA phasic volume parameters. CONCLUSIONS: In AS, changes in LA function did not parallel changes in LA size. Furthermore, the increase in LA volume does not necessarily reflect the presence of intrinsic LA dysfunctio

    Roles of domain-general auditory processing in spoken second-language vocabulary attainment in adulthood

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    Recently, scholars have begun to explore the hypothesis that individual differences in domain-general auditory perception, which has been identified as an anchor of L1 acquisition, could explain some variance in postpubertal L2 learners’ segmental and suprasegmental learning in immersive settings. The current study set out to examine the generalizability of the topic to the acquisition of higher-level linguistic production skills—that is the appropriate use of diverse, rich, and abstract vocabulary. The speech of 100 Polish-English bilinguals was elicited using an interview task, submitted to corpus-/rater-based linguistic analyses, and linked to their ability to discriminate sounds based on individual acoustic dimensions (pitch, duration, and amplitude). According to the results, those who attained more advanced L2 lexical proficiency demonstrated not only more relevant experience (extensive immersion and earlier age of arrival), but also more precise auditory perception ability

    Photodegradable Antimicrobial Agents: Synthesis and Mechanism of Degradation

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    As a strategy to inactivate antimicrobial agents after use, we designed a range of ethanolamine derivatives where four of them possessed interesting activity. The ethanolamine moiety facilitates photodecomposition, which in a potential drug will take place after use. Herein, the synthetic preparation of these compounds and the mechanism of photoinactivation are described.publishedVersio

    Evaluation of photodegradable chitin synthetase inhibitors for the treatment of salmon lice (Lepeophtheirus salmonis)

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    Some photolabile ethanolamine analogues of the chitin synthetase inhibitors diflubenzuron, teflubenzuron, and lufenuron were tested for activity as anti-lice compounds towards salmon lice (Lepeophtheirus salmonis). Two teflubenzuron analogues (2 and 3) exhibited interesting biological activity whereas their corresponding photodecomposition products were inactive. One of the analogues (3) decomposes completely when irradiated at pH 8, a relevant pH for seawater. In comparison, diflubenzuron showed a 66% photodecomposition under identical conditions. Thus, ethanolamine 3 is an interesting lead compound in the search for a powerful, environmentally friendly chemical to use in salmon-lice treatment.publishedVersio

    Developing, Analyzing and Sharing Multivariate Datasets: Individual Differences in L2 Learning Revisited

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    Following the trends established in psychology and emerging in L2 research, we explain our support for an Open Science approach in this paper (i.e., developing, analyzing and sharing datasets) as a way to answer controversial and complex questions in applied linguistics. We illustrate this with a focus on a frequently debated question, what underlies individual differences in the dynamic system of post-pubertal L2 speech learning? We provide a detailed description of our dataset which consists of spontaneous speech samples, elicited from 110 late L2 speakers in the UK with diverse linguistic, experiential and sociopsychological backgrounds, rated by ten L1 English listeners for comprehensibility and nativelikeness. We explain how we examined the source of individual differences by linking different levels of L2 speech performance to a range of learner-extrinsic and intrinsic variables related to first language backgrounds, age, experience, motivation, awareness, and attitudes using a series of factor and Bayesian mixed-effects ordinal regression analyses. We conclude with a range of suggestions for the fields of applied linguistics and SLA, including the use of Bayesian methods in analyzing multivariate, multifactorial data of this kind, and advocating for publicly available datasets. In keeping with recommendations for increasing openness of the field, we invite readers to rethink and redo our analyses and interpretations from multiple angles by making our dataset and coding publicly available as part of our 40th anniversary ARAL article

    Effekt av botanisk sammensetning i surfôr på omsetning av fettløselige vitaminer i vom og overføring til melk

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    Det var en tilsynelatende netto økning av α-tokoferol i vomma mens omtrent halvparten av β-karoten ble brutt ned. Surfôr fra Kortvarig økologisk eng som inneholdt rødkløver ga melk med lavere innhold av fettløselige vitaminer enn de andre surfôrslagen
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