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991.
Although the effect of acoustic cues on speech segmentation has been extensively investigated, the role of higher order information (e.g., syntax) has received less attention. Here, the authors examined whether syntactic expectations based on subject-verb agreement have an effect on segmentation and whether they do so despite conflicting acoustic cues. Although participants detected target words faster in phrases containing adequate acoustic cues ("spins" in take spins and "pins" in takes pins), this acoustic effect was suppressed when the phrases were appended to a plural context (those women take spins/*takes pins [with the asterisk indicating a syntactically unacceptable parse]). The syntactically congruent target ("spins") was detected faster regardless of the acoustics. However, a singular context (that woman *take spins/takes pins) had no effect on segmentation, and the results resembled those of the neutral phrases. Subsequent experiments showed that the discrepancy was due to the relative time course of syntactic expectations and acoustics cues. Taken together, the data suggest that syntactic knowledge can facilitate segmentation but that its effect is substantially attenuated if conflicting acoustic cues are encountered before full realization of the syntactic constraint. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
The authors use a developmental perspective to examine questions about the criminal culpability of juveniles and the juvenile death penalty. Under principles of criminal law, culpability is mitigated when the actor's decision-making capacity is diminished, when the criminal act was coerced, or when the act was out of character. The authors argue that juveniles should not be held to the same standards of criminal responsibility as adults, because adolescents' decision-making capacity is diminished, they are less able to resist coercive influence, and their character is still undergoing change. The uniqueness of immaturity as a mitigating condition argues for a commitment to a legal environment under which most youths are dealt with in a separate justice system and none are eligible for capital punishment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
The self-perceptions of children with attention-deficit/hyperactivity disorder (ADHD; n=487) were compared with those of children in a local normative comparison group (n=287), relative to teacher- and parent-rated perceptions of their competence. Children were participants in the ongoing follow-up portion of the Multimodal Treatment Study of Children with ADHD. Children with ADHD were much more likely than comparison children to overestimate their competence relative to adult report, regardless of who was used as the criterion rater (teacher, mother, or father). Examination by comorbidity subgroups revealed that children with ADHD inflated their self-perceptions the most in domains of greatest deficit. Gender effects also are reported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
Reviews the clinical features of the major classes of civilian PTSD that psychotherapists are most likely to encounter including medical procedures, pain, crime and the social environment, traffic accidents, traumatic brain injury, and the toxic stress syndrome. Psychotherapeutic strategies that clinicians can productively employ to treat civilian PTSD are discussed including supportive therapy, behavioral approaches, and psychodynamic psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
The draft European Commission directive on packaging and packaging waste sets ambitious targets for recovery and states that recycle must contribute an important part of recovery. To meet these targets, there will inevitably be pressure to recycle plastics back into food contact uses. This legislative driving force is coupled with considerable consumer pressure. However, it must be accepted that there will be many, perhaps even a majority, of food applications where recycle or re-use of plastics is not desirable and these plastics must be put to alternative uses. Protection of the environment must not be at the expense of public health. This paper outlines the issues involved and describes a multi-centre European project that aims to define criteria to ensure the quality and safety-in-use of recovered plastics for food contact.  相似文献   
996.
The purpose of the study was to investigate molecular changes associated with glioma tissues using FT-IR microspectroscopic imaging (FT-IRM). A multivariate statistical analysis allowed one to successfully discriminate between normal, tumoral, peri-tumoral, and necrotic tissue structures. Structural changes were mainly related to qualitative and quantitative changes in lipid content, proteins, and nucleic acids that can be used as spectroscopic markers for this pathology. We have developed a spectroscopic model of glioma to quantify these chemical changes. The model constructed includes individual FT-IR spectra of normal and glioma brain constituents such as lipids, DNA, and proteins (measured on delipidized tissue). Modeling of FT-IR spectra yielded fit coefficients reflecting the chemical changes associated with a tumor. Our results demonstrate the ability of FT-IRM to assess the importance and distribution of each individual constituent and its variation in normal brain structures as well as in the different pathological states of glioma. We demonstrated that (i) cholesterol and phosphatidylethanolamine contributions are highest in corpus callosum and anterior commissure but decrease gradually towards the cortex surface as well as in the tumor, (ii) phosphatidylcholine contribution is highest in the cortex and decreases in the tumor, (iii) galactocerebroside is localized only in white, but not in gray matter, and decreases in the vital tumor region while the necrosis area shows a higher concentration of this cerebroside, (iv) DNA and oleic acid increase in the tumor as compared to gray matter. This approach could, in the future, contribute to enhance diagnostic accuracy, improve the grading, prognosis, and play a vital role in therapeutic strategy and monitoring.  相似文献   
997.
Blue light is used in dental practise to cure resin-based materials, but the path of the light often includes oral tissues such as gingival tissues. While adverse effects of blue light exposure on cells – such as retina cells – are well known, few studies have investigated the impact of blue light exposure on oral cells. The aim of the present in vitro study was to assess the biological effects of blue light emitted by two dental curing devices (a plasma-arc and a light-emitting diode curing unit) on human gingival fibroblasts. Light intensities and light-induced temperature rise were respectively measured with a radiometer and a thermocouple. Cellular response to blue light exposure was assessed by the observation of cell morphology (scanning electron microscopy) and the estimation of cell mitochondrial activity (MTT assay). Light intensities measured at the clinical distance were 488 ± 42 mW/cm2 for the plasma-arc unit and ranged from 61 ± 5 to 140 ± 16 mW/cm2 for the light-emitting diodes unit, according to the curing program used. The highest temperature rise was 0.5 and 3.5 °C for exposure to the plasma-arc light and to the light-emitting diodes light, respectively. Results showed no differences between exposed- and non-exposed cells in regards to cell morphology. However, cells exposed to blue light presented an increased mitochondrial activity compared to control cells (non-exposed), and mostly those exposed to plasma-arc light.  相似文献   
998.
The aim of this study was a better understanding of the regulation mechanisms of in vitro osteoblast activity on biomaterials. Rat osteoblast behaviour on different surfaces was studied. Surfaces with different roughness (and a similar surface chemistry) or with different surface chemistry (and a similar roughness) were compared. Cellular morphology was observed by scanning electron microscopy and cell adhesion was quantified using an image analysis system. Osteoblast proliferation was quantified by a MTT test and total protein content and alkaline phosphatase (ALP) activity were evaluated by spectrophotometry. Data were compared by statistical analysis.

Results showed that NiTi surface roughness did not influence osteoblasts morphology, adhesion, total protein content and ALP activity whereas it modulated cell proliferation. Roughness was shown to stimulate cell proliferation. For smooth surfaces exhibiting two different chemical compositions, adhesion rate was found to be higher on Thermanox® than on NiTi whereas proliferation was shown to be smaller. ALP activity was also modulated by surface chemistry. Thus, cell adhesion and ALP activity were found to be more governed by surface chemistry than by roughness whereas cell proliferation was shown to be modulated by roughness (this effect increasing during cell culture) and by chemistry (this effect remaining stable in time) together. Total protein content and cell morphology were found to be independent of both parameters (roughness and chemistry). Effects of surface chemistry were discussed in terms of wettability and electron acceptor/donor properties of the surfaces of interest. Immunofluorescence images of adhesion proteins could not demonstrate differences between the three surfaces.  相似文献   

999.
Due to their bad effects on human health and comfort, removing particles and volatile organic compounds from indoor air has become an issue of major interest. In this study, the potential use of five media for particle removal was investigated: a felt, a cloth, and a knitted fabric made entirely of activated carbon fibers, and two prototype nonwovens made of different proportions of activated carbon and glass fibers. Dynamic filtration measurements were performed in experimental conditions as representative as possible of indoor air, with alumina particles (modal diameter: 0.37?μm), at an inlet concentration of 2,500?particles?cm?3 and for two different frontal velocities of air: 0.37 and 0.50?m?s?1. Although this medium was not designed for filtration, felt exhibited a high initial filtration efficiency (74%) for a low pressure drop (less than 210?Pa). Similarly, associating several layers of woven/knitted media in series led to high performances, as it reduced preferential paths for the airflow. Finally, prototype nonwovens appeared more efficient than activated carbon felt, but exhibited higher pressure drops.  相似文献   
1000.
The development of secondary mortgage market activities such as portfolio sales and mortgage securitisation attests to the increasingly sophisticated character of housing finance in developed economies. In the US, where mortgage securitisation is well established, the mortgage‐backed securities (MBS) market is currently valued in excess of US$1000 billion. Elsewhere, mortgage securitisation is emerging within the context of a variety of regulatory frameworks and institutional settings. This paper reviews international trends in mortgage securitisation and then examines, via a case study of New Zealand, the consequences of a problem securitisation for institutions, the state and individual mortgagors. It is argued that as MBS markets evolve the needs of investors and credit agencies are likely to impact upon home owners housing experiences. Consequently, there is a need for housing policy to take cognisance of secondary mortgage market developments. A glossary of terms is provided in an Appendix.  相似文献   
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