269 research outputs found
Role of configurational entropy in the thermodynamics of clusters of point defects in crystalline solids
The internal configurational entropy of point defect clusters in crystalline silicon is studied in detail by analyzing their potential energy landscapes. Both on-lattice and off-lattice calculation approaches are employed to demonstrate the importance of off-lattice configurational states that arise due to a large number of inherent structures (local minima) in the energy landscape generated by the interatomic potential function. The resulting cluster configurational entropy of formation is shown to exhibit behavior that is qualitatively similar to that observed in supercooled liquids and amorphous solids and substantially alters the thermodynamic properties of point defect clusters in crystals at high temperature. This behavior is shown to be independent of interatomic potential and cluster type, and suggests that defects in crystals at high temperature should be generally described by a quasicontinuous collection of nondegenerate states rather than as a single ground state structure. The modified thermodynamic properties of vacancy clusters at high temperature are found to explain a longstanding discrepancy between simulation predictions and experimental measurements of vacancy aggregation dynamics in silicon
Endophytic Fungi of Tomato and Their Potential Applications for Crop Improvement
In this work, considerations are made to the effects and methods of introduction and detection of Endophytic Fungi on tomato plants, consolidating in a review the main findings that regard pest and pathogen control, and improvement of plant performance. Moreover, a survey was undertaken of the naturally occurring constitutive endophytes present in this horticultural crop, with the aim to evaluate the potential role in the selection of new beneficial Endophytic Fungi useful for tomato crop improvement
On-lattice kinetic Monte Carlo simulations of point defect aggregation in entropically influenced crystalline systems
An on-lattice kinetic Monte Carlo model of vacancy aggregation in crystalline silicon is parametrized using direct regression to evolution data from nonequilibrium molecular dynamics simulations. The approach bypasses the need to manually compute an energy barrier for each possible transition and leads to an excellent, robust representation of the molecular dynamics data. We show that the resulting lattice kinetic Monte Carlo model correctly captures the behavior of the real, continuous space system by properly accounting for continuous space entropic effects, which are often neglected in lattice-based models of atomistic processes. These contributions are particularly important at the high temperatures relevant to many steps in semiconductor materials processing
How people talk about each other: Modeling Generalized Intergroup Bias and Emotion
Current studies of bias in NLP rely mainly on identifying (unwanted or
negative) bias towards a specific demographic group. While this has led to
progress recognizing and mitigating negative bias, and having a clear notion of
the targeted group is necessary, it is not always practical. In this work we
extrapolate to a broader notion of bias, rooted in social science and
psychology literature. We move towards predicting interpersonal group
relationship (IGR) - modeling the relationship between the speaker and the
target in an utterance - using fine-grained interpersonal emotions as an
anchor. We build and release a dataset of English tweets by US Congress members
annotated for interpersonal emotion -- the first of its kind, and 'found
supervision' for IGR labels; our analyses show that subtle emotional signals
are indicative of different biases. While humans can perform better than chance
at identifying IGR given an utterance, we show that neural models perform much
better; furthermore, a shared encoding between IGR and interpersonal perceived
emotion enabled performance gains in both tasks. Data and code for this paper
are available at https://github.com/venkatasg/interpersonal-biasComment: To be presented at EACL 202
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The Utility of Outcome Studies in Plastic Surgery
Summary: Outcome studies help provide the evidence-based science rationalizing treatment end results that factor the experience of patients and the impact on society. They improve the recognition of the shortcoming in clinical practice and provide the foundation for the development of gold standard care. With such evidence, health care practitioners can develop evidence-based justification for treatments and offer patients with superior informed consent for their treatment options. Furthermore, health care and insurance agencies can recognize improved cost-benefit options in the purpose of disease prevention and alleviation of its impact on the patient and society. Health care outcomes are ultimately measured by the treatment of disease, the reduction of symptoms, the normalization of laboratory results and physical measures, saving a life, and patient satisfaction. In this review, we outline the tools available to measure outcomes in plastic surgery and subsequently allow the objective measurements of plastic surgical conditions. Six major outcome categories are discussed: (1) functional measures; (2) preference-based measures and utility outcome scores; (3) patient satisfaction; (4) health outcomes and time; (5) other tools: patient-reported outcome measurement information system, BREAST-Q, and Tracking Operations and Outcomes for Plastic Surgeons; and (6) cost-effectiveness analysis. We use breast hypertrophy requiring breast reduction as an example throughout this review as a representative plastic surgical condition with multiple treatments available
Poisoning by non-edible squash: retrospective series of 353 patients from French Poison Control Centers
CONTEXT: Among the numerous varieties of squash that exist, some are edible while other bitter-tasting ones are not fit for human consumption. Cases of confusion seem to be multiplying and are characterized by digestive problems (diarrhea, vomiting, and abdominal pain).
METHODS: This is a descriptive retrospective study of cases of exposure reported to French Poison Control Centers between 1 January 2012 and 12 December 2016.
RESULTS: 353 patients were included, with 71.7% belonging to collective cases of poisoning. The male to female sex ratio was 0.75 for an average age of 38.2 ± 23.6 years. The circumstances of exposure were dietary for 337 patients (95.5%). The majority of the squash consumed was purchased at a store (55.8%) but some also came from the garden (25.5%). 204 patients (57.8%) mostly presented with diarrhea, vomiting, abdominal pain, sometimes with the consequent dehydration, hypotension, tachycardia, headaches, or vertigo. There were no deaths or severe (Poisoning Severity Score (PSS) 3) cases, but there were 14 patients (4.0%) of moderate severity, 190 patients (53.8%) of minor severity (PSS 1), and 149 patients (42.2%) without severity (PSS 0) but among which we include the bitter taste of the squash. The average age of PSS 2 patients was significantly (p = .003) older than that of the PSS <2 patients.
CONCLUSION: As the first consequential series in Europe, our study shows that exposure to non-edible squash is frequent. Usually benign, poisoning could be the consequence of the irritating effect of certain cucurbits, the molecules responsible for the taste and toxicity of the fruits. In terms of prevention therefore, we recommend disposing of any squash with a bitter taste
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