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21.
This paper describes a study on the contribution of linguistically-informed features to the task of quality estimation for machine translation at sentence level. A standard regression algorithm is used to build models using a combination of linguistic and non-linguistic features extracted from the input text and its machine translation. Experiments with three English–Spanish translation datasets show that linguistic features on their own are not able to outperform shallower features based on statistics from the input text, its translation and additional corpora. However, further analysis suggests that linguistic information can be useful to produce better results if carefully combined with other features. An in-depth analysis of the results highlights a number of issues related to the use of linguistic features.  相似文献   
22.
The emergence of psychiatric rehabilitation and the recovery movement generate new and expanded roles for psychologists in services for people with serious mental illness (SMI). However, the proportion of psychologists working in SMI services today is substantially less than previous decades. This article reviews the roles of psychologists in various mental health systems and outlines the contributions that psychologists can make in implementing evidence based approaches for people with SMI. A survey of American Psychology Association (APA)-accredited Council of University Directors of Clinical Psychology (CUDCP) Clinical Psychology doctoral programs was conducted. The results of the survey indicate an increase, since the early 1990s, in clinical faculty with SMI interests, and suggest that many graduate programs provide opportunities for SMI-relevant research and practicum training. However, the survey also indicates a lack of coursework on topics relevant to SMI and a lack of coursework relevant to assuming administrative and leadership roles in the mental health system. Despite training opportunities in graduate school, production of new PhDs who choose the SMI field is unlikely to meet the demand. According to the present study, the limiting factor is not availability of training, but student career choice. The opportunities and challenges that psychologists face in SMI recovery-oriented service delivery are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
Hysteretic rate-independent constitutive laws are introduced within the framework of continuum thermodynamics with internal variables and revisited using concepts and arguments related to dynamical system theory. The evolution of internal variables is formulated either by a system of differential equations or by the associated phase flow. The restrictions implied by rate independence and thermodynamics are pointed out. Within this framework, the class of models with Masing hysteretic rules and Bouc endochronic relations are reviewed, and notions such as irreversibility, noninvertibility, and memory effects are discussed having recourse to different choices of internal variables. By introducing plastic strain as the internal variable, thermodynamic admissibility is proved for both models. However, while the processes with Masing rules exhibit a limited memory and are therefore noninvertible, the processes based on Bouc models are shown to have full memory and to be invertible though irreversible.  相似文献   
24.
The present contribution focuses on the modification of a 160/220 bituminous binder with clay and polymer/clay nanocomposites. Bitumen/polymer/clay ternary blends were prepared using styrene–butadiene–styrene, ethylene vinyl acetate and ethylene methylacrylate copolymers mixed with an organomodified montmorillonite. Dynamic mechanical analyses were performed in the extended domain of stress, temperature and frequency to analyse the thermorheological behaviour of the blends. The time–temperature superposition principle was applied to shift the experimental data recorded at different temperatures and generate master curves of the linear viscoelastic functions. For all blends, the mechanical response of the system was found to be strongly and intimately influenced by the nanocomposite modification. In some cases, a solid-like behaviour appears and delays the Newtonian transition. Morphological analyses performed with fluorescence microscopy allowed to associate the binder properties with the presence of clay silicates, which alter the colloidal equilibrium of the bitumen and enhances the compatibility between bitumen and polymers. Based on the morphological and rheological results, a structural model of the prepared blends is proposed.  相似文献   
25.
BACKGROUND/AIMS: In surgery for achalasia, the length of the myotomy and the opportunity of associating an antireflux procedure are still debated. Prospective and comparative studies on different techniques are few. The aims of this work is to compare the long term results of three different techniques successively adopted by the same surgical group. MATERIALS AND METHODS: Between January 1955 and December 1991, 185 achalasic patients were submitted to myotomy by using in temporal sequence three different techniques. The first technique utilized (1955-1972) was a long esophagogastric abdominal myotomy (83 patients), secondly (1973-1978) a limited transthoracic myotomy (30 patients) and at last (1979-1991) a long esophagogastric abdominal myotomy associated to the Dor gastroplasty (72 patients). Since 1972, patients were prospectively followed up according to a protocol which included a clinical interview, x-rays, manometry and endoscopy at given dates. Post-operative esophagogastric transit and gastro-esophageal reflux were assessed to verify the therapeutical outcome. Results obtained with the three different techniques were analyzed and compared by using the actuarial Kaplan-Meier curves. RESULTS: The mean follow up was 193.3 months for the patient group that underwent abdominal myotomy (62/83 patients), 137.3 months for the thoracic myotomy group (30/30 patients) and 86.9 months for the abdominal myotomy plus Dor gastroplasty group (69/72 patients). Long-term results in the abdominal myotomy and in the thoracic myotomy groups were respectively poor in 51.6% and in 46.6% of patients. Major causes of failure were insufficient myotomy (6.5%), periesophageal scarring (9.6%) and reflux esophagitis (22.6%) for the abdominal myotomy group; insufficient myotomy (20%) and reflux esophagitis (23%) for the thoracic myotomy group. In the abdominal myotomy plus Dor gastroplasty group long-term results were excellent or good in 87% of patients and poor in 13%. Reflux esophagitis (10% of cases) was the principal cause of failure. CONCLUSIONS: The comparison of the actuarial curves shows a significantly better long term outcome for the abdominal myotomy plus Dor antireflux procedure than for the abdominal myotomy (p = 0.01) and for the thoracic myotomy (p = 0.002) techniques.  相似文献   
26.
27.
Velocity-voidage experiments conducted on beds of truly monosized and spherical plastic particles fluidised by solutions of glycerol, enable the change of behaviour at high expansion conditions to be correlated with the unhindered particle Reynolds number.  相似文献   
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29.
Interactions between the intestinal microbiota, immune system and nervous system are essential for homeostasis in the gut. Inflammasomes contribute to innate immunity and brain–gut interactions, but their role in microbiota–neuro–immune interactions is not clear. Therefore, we investigated the effect of the inflammasome on visceral pain and local and systemic neuroimmune responses after antibiotic-induced changes to the microbiota. Wild-type (WT) and caspase-1/11 deficient (Casp1 KO) mice were orally treated for 2 weeks with an antibiotic cocktail (Abx, Bacitracin A and Neomycin), followed by quantification of representative fecal commensals (by qPCR), cecal short chain fatty acids (by HPLC), pathways implicated in the gut–neuro-immune axis (by RT-qPCR, immunofluorescence staining, and flow cytometry) in addition to capsaicin-induced visceral pain responses. Abx-treatment in WT-mice resulted in an increase in colonic macrophages, central neuro-immune interactions, colonic inflammasome and nociceptive receptor gene expression and a reduction in capsaicin-induced visceral pain. In contrast, these responses were attenuated in Abx-treated Casp1 KO mice. Collectively, the data indicate an important role for the inflammasome pathway in functional and inflammatory gastrointestinal conditions where pain and alterations in microbiota composition are prominent.  相似文献   
30.
This paper describes the development of pH-sensitive poly(methyl methacrylate-acrylic acid) copolymers for the enteric coating of pharmaceutical products for oral administration. To obtain the dissolution at the desired pH level, different pH-sensitive polymers are available on the market. Usually, for each desired dissolution pH, an ad hoc polymer is designed. Thus, different dissolution pH values could ask for completely different polymers. Instead, the materials proposed in this work are copolymers of the same two monomers, and the different dissolution pH was obtained by changing the volume fraction of the hydrophobic methyl methacrylate monomer to the hydrophilic acrylic acid monomer. Increasing the volumetric percentage of methyl methacrylate causes the polymer to dissolve at increasing pH, until the dissolution does not take place at all, and it is replaced by a slow swelling phenomenon. The copolymers obtained were characterized by differential scanning calorimetry, in order to evaluate their glass transition temperature, and these latter were related to %MMA. The molecular weights of the pure polymers (PAA, PMMA) were measured by intrinsic viscosity, to further validate the glass transition temperatures observed. The dissolution of the copolymers was carefully tested in buffer solutions for a dense set of pH values. A linear relationship between dissolution pH and volumetric percentage of methyl methacrylate was obtained from these measurements. As a result, for any physiological compartment, the copolymer which dissolves at the pH of interest can be easily synthesized.  相似文献   
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