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11.
Reviews the empirical literature available on the phenomenon of depression in Alzheimer's disease (AD). Although not extensively studied, there is accumulating evidence to suggest that depression affects a large number of patients with AD and can have profound effects on both the long-term functioning of these patients and the well-being of their caregivers. Thus far, the field is dominated by studies of prevalence. Considerably rarer are studies investigating etiology, association with other aspects of the disease, impact on patients and caregivers, assessment, and treatment. The conceptual issues, methodological differences, and implications of the studies that exist thus far are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Compared attributions for negative wife behavior offered by 3 groups of husbands: 22 maritally violent and distressed, 17 nonviolent but maritally distressed, and 17 nonviolent and nondistressed. Husbands rated wife behaviors presented in 9 hypothetical problematic marital situation vignettes. On a measure of responsibility attributions, violent husbands were more likely than nondistressed husbands to attribute negative intentions, selfish motivation, and blame to the wife. On a measure of possible negative wife intentions, violent husbands were more likely than either distressed or nondistressed men to attribute negative intentions to the wife. Exploratory analyses suggested that certain types of marital situations (e.g., jealousy and rejection from wife) were particularly likely to elicit attributions of negative intent from violent husbands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Abstract: Researchers frequently approach questions dealing with local fiscal decision‐making using economic models. These models typically base the demand for public services on a set of socioeconomic characteristics that serve as rough proxies for voter preferences. Our study focuses more directly on preference formation and explores the nature of the relationship between citizens’ attitudes about police services and their willingness to pay for them. We pay particular attention to the role of demographic traits, television media, and direct contact with service providers. We present data from a survey of Connecticut adults and use these data to test direct and indirect effects models with regression analysis. We find evidence that attitudes about police predict willingness to pay for police services, holding the demographic attributes of respondents constant. We also find that the effects of some demographic traits on demand for services are mediated by preferences, as are some types of experience and media exposure.  相似文献   
14.
The study used latent growth modeling to investigate longitudinal relationships between individuation, peer alcohol use, and adolescent alcohol use among African American, Mexican American, and non-Hispanic White adolescents (N=6,048) from 7th, 8th, and 9th grades over a 3-year period. Initial levels of peer alcohol use were significantly related to changes in adolescents' alcohol use, whereas initial adolescent alcohol use also significantly related to changes in peers' alcohol use, suggesting a bidirectional relationship. Higher levels of intergenerational individuation were related to smaller increases in adolescent alcohol use and higher levels of separation were related to larger increases in youth drinking. The findings were similar across ethnic groups. Implications for development of prevention and intervention programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
Social and emotional competence were evaluated using self-report and behavioral measures in adults with attention-deficit/hyperactivity disorder (ADHD) and controls. Adults with ADHD viewed themselves as less socially competent but more sensitive toward violations of social norms than controls. Films depicting emotional interactions were used to assess linguistic properties of free recall and perceived emotional intensity. Although adults with ADHD used more words to describe the scenes, they used fewer emotion-related words, despite rating the emotions depicted as more intense than did controls. In contrast, no group differences for words depicting social or cognitive processes were observed. Overall, adults with ADHD appear more aware of their problems in social versus emotional skills. Findings may have implications for improving the psychosocial functioning of these adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
The transport of video images is likely to be a major application of high-speed networks of the future. These applications are capable of utilizing the high bandwidths that will become available with the advent of B-ISDN. In this paper, we propose a new methodology (called TES) for modeling the frame bitrate stream generated by compressed video sources. The main characteristic of this method is that it can model an arbitrary marginal distribution and approximate the autocorrelation structure of the random bitrate process generated by compressed frames. We present a modeling example utilizing this method, based on data from a video coding algorithm employing a layering technique. Using the source model, we develop a simulation model of a multiplexer of video sources. We show that this model can be used to address a number of design issues that arise in this class of problem. In particular, we show that for a layered video coding algorithm, it is possible to have a gain in the number of sources multiplexed at the cost of some loss of low priority packets.  相似文献   
17.
This paper will demonstrate how Sequence Package Analysis, as a new natural language understanding method that is built on a set of parsing structures that consist of context-free grammatical units and related prosodic features for identifying affective/emotional data found in natural speech and blogs, may better accommodate the goals of crisis management and rapid decision making in critical systems. Following an in depth discussion of the genesis and development of this method for the design of voice-user interfaces and audio mining programs, debuted in an earlier issue of IJST, this paper will attempt to show how Sequence Package Analysis can improve human response in monitoring recorded conversations of terror suspects and the recordings of help-line desks. In both instances, effective human intervention may help avert a crisis and resulting liability. The paper’s limited focus on these two respective domains does not, however, limit the applicability of Sequence Package Analysis to other critical systems, inasmuch as the parsing structures explained below are generic enough to be applied to other critical systems, such as ambulance control, aircraft or nuclear power stations, or 911 calls for help. Given that critical systems require effective human response from decision makers, natural language data must be accorded the same kind of scientific scrutiny given to graphic design and other features of human-computer interaction.  相似文献   
18.
Lipid oxidation is a major factor affecting flavor quality and shelf life of vegetable oils. Oxidative stability is therefore an important criterion by which oils are judged for usefulness in various food applications. In this study a method based on headspace analysis was developed to evaluate relative oxidative stability of canola oils. The method does not require the use of chemicals, involves minimal sample preparation, and can be performed on a relatively small sample size in comparison with traditional wet chemical methods. Canola oils freshly extracted in the laboratory from different seed samples were subjected to accelerated oxidation and analyzed for PV by standard methods and headspace volatiles by solid phase microextraction/GC-MS. Forward stepwise regression analysis of the data revealed a relationship between PV and headspace concentration of the volatile lipid oxidation products hexanal and trans,trans-2,4-heptadienal. The PV calculated using this formula correlated (R 2=0.73) with those measured by conventional methods. Presented in part at the 96th Annual Meeting of the AOCS, 1–4 May 2005, Salt Lake City, UT.  相似文献   
19.
Individual FA have diverse biological effects, some of which affect the risk of cardiovascular disease (CVD). In the context of food-based dietary guidance designed to reduce CVD risk, fat and FA recommendations focus on reducing saturated FA (SFA) and trans FA (TFA), and ensuring an adequate intake of unsaturated FA. Because stearic acid shares many physical properties with the other long-chain SFA but has different physiological effects, it is being evaluated as a substitute for TFA in food manufacturing. For stearic acid to become the primary replacement for TFA, it is essential that its physical properties and biological effects be well understood.  相似文献   
20.
The effect of molecular architecture on the evolution of viscoelastic properties during crystallization was investigated using ethylene-hexene copolymers manufactured via metallocene (M-LLDPE) and Ziegler-Natta (ZN-LLDPE) processes. Differences in branching distribution were shown to have a drastic effect on the viscoelastic properties near the gel point. It is shown that the branching distribution rather than branch content is the determining parameter for the evolution of the rheological properties during isothermal and non-isothermal crystallization, and for the width of the solidification interval. We developed a partial melting technique for the preparation of stable critical gels of LLDPE whose viscoelastic properties correspond to the intermediate state between melt and solid. Local molecular conformation and crystallinity in these gels were characterized by Raman spectroscopy, which shows that the transition from melt-like to solid-like rheological behavior (physical gelation) in LLDPE occurs at a very low overall crystallinity of less than 5%.  相似文献   
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