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141.
Investigated burden experienced by 60 spouses and 71 parents who served as primary caregivers to individuals with traumatic brain injury (BI). Burden levels, as assessed by the Questionnaire on Resources and Stress (QRS-SF), were compared for spouses and parents. Both parents and spouses exhibited high levels of burden. Relative to spouses, parents reported significantly greater burden related to lifespan care. Spouses reported significantly less personal reward than did parents. The presence of social aggression and cognitive disability in the individual with BI was found to have a greater association with subjective burden of caregivers than was the presence of physical disability or injury severity. Results of previous studies with QRS-SF scores show that the responsibility assumed by spouses and parents of persons with BI was as great as that experienced by families of people with severe chronic physical disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
142.
Reports the death of L. E. Tyler, who served as the 81st president of the American Psychological Association. Her view was that the purpose of counseling was to encourage natural, life-long developmental processes as distinguished from psychotherapy, which she felt was more appropriate to clinicians' dealings with disturbances of personality. It is noted that Tyler's concern for clarifying the human puzzle of personal change moved, over time, from individual differences to individuality and from a psychometric perspective to a systems–ecological view of real-world choices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
143.
In contrast to D. C. Zuroff, M. Mongrain, and D. A. Santor (2004), the current authors find the promissory note of dependency-sociotropy (DEP-SOC) and self-criticism-autonomy (SC-AUT) as a model of risk for depression to be in default. The authors propose reorganizing what has been cast as unitary effort into 3 distinct endeavors: a psychoanalytic clinical theory, development of a refined empirical model of risk for clinical depression, and research examining the effects of DEP-SOC and SC-AUT on interpersonal relationships in nonclinical samples. The authors identify some issues that need to be accommodated regardless of whether the assessment of Zuroff et al. (2004) or their own is accepted. DEP-SOC and SC-AUT are best construed as correlated, continuous dimensions. Future work also needs to accommodate depression as chronic recurrent condition, advances in developmental psychopathology, and more stringent criteria for positing a risk factor for clinical disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
144.
In this paper we consider two results motivated by Livsic's well-known theorem that, for a hyperbolic system, a Hölder continuous function is determined, up to a coboundary, by its values around closed orbits. The first result relates to negative values around orbits and the second result to values for finitely many orbits. We also present some new results on maximizing measures and the boundary of the unit ball in the stable norm for a surface.  相似文献   
145.
Unconrolled agglomeration of particles and adhesion of the particulate mass to wall surfaces are common severe problems in many drying operations. This paper reviews the mechanisms of interparticle and particle-surface attraction as well as the theory and the existing tests for characterising powders in terms of internal strength, wall friction and adhesion. The usefulness of the information obtained from these tests in dryer design and operation is critically reviewed. The importance of powder stickiness in various types of dryers is discussed and established methods of combating the problem are presented Recommendations an made for further research in the area of powder cohesion and adhesion.  相似文献   
146.
Dielectric relaxation measurements are reported over a frequency range from 10−1 to 109 Hz as a function of exposure time for an epoxy resin-carbon fibre composite, ageing at 60 °C in water. Investigation of the nature of the dipole relaxation of the water molecules, indicates the nature of their interaction with the polymer matrix. Analysis of the dielectric relaxation spectra allow identification of processes that can be attributed to ‘free’ and ‘bonded’ water, water in micro-cracking, located in carbon fibre disbonds and plasticizing the polymer matrix. Identification of the various types of location in which water exists was aided by use of the Ng factor from the Kirkwood-Frölich equation, which describes the constraints on free dipole ration nature imposed by the environment in which it is located. These data indicate the power of the dielectric technique for quantitative analysis of water ingress into epoxy composites.  相似文献   
147.
We conducted two experiments to examine the relations among characteristics of how Type A individuals strive for achievement, including goal achievement, self-evaluation, and psychological distress. We evaluated these relations as subjects performed two sequential general information tests. Experiment 1 indicated that achievement striving associated with the Type A behavior pattern is characterized by a tendency to set personal goals in excess of performance and is associated with a low probability of achieving goals. The results of Experiment 2 indicated that the achievement strategy Type A individuals adopted was associated with low self-evaluation of their actual performance. Furthermore, a pre- and postexperiment self-report questionnaire of psychological state suggested that failure to achieve personal goals was related to increased psychological distress. The results of our study suggest that unrealistically high performance standards and failure to achieve personal goals may be a mechanism that triggers the negative psychological states and performance dissatisfaction associated with the Type A behavior pattern. Our study also supports theoretical conceptualizations that excessive achievement striving can act as a potential motivational mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
148.
Glenn  Richard R.  Suresh   《Computers & Security》2006,25(8):600-615
Network Denial-of-Service (DoS) attacks that disable network services by flooding them with spurious packets are on the rise. Criminals with large networks (botnets) of compromised nodes (zombies) use the threat of DoS attacks to extort legitimate companies. To fight these threats and ensure network reliability, early detection of these attacks is critical. Many methods have been developed with limited success to date. This paper presents an approach that identifies change points in the time series of network packet arrival rates. The proposed process has two stages: (i) statistical analysis that finds the rate of increase of network traffic, and (ii) wavelet analysis of the network statistics that quickly detects the sudden increases in packet arrival rates characteristic of botnet attacks.Most intrusion detections are tested using data sets from special security testing configurations, which leads to unacceptable false positive rates being found when they are used in the real world. We test our approach using data from both network simulations and a large operational network. The true and false positive detection rates are determined for both data sets, and receiver operating curves use these rates to find optimal parameters for our approach. Evaluation using operational data proves the effectiveness of our approach.  相似文献   
149.
Previous research has shown that a combination of feed restriction and dietary 1,3-butanediol starting at 14 d post-partum resulted in fatty liver and ketosis. Sixteen multiparous Holstein cows were used to determine effects of feed restriction or 1,3-butanediol as separate treatments. Treatments during d 14 to 42 postpartum were 1) control (ad libitum intake), 2) 20% feed restriction, or 3) control plus dietary 1,3-butanediol (5.5% of DM). From d 43 to 56, cows assigned to treatments 2 and 3 received a combination of feed restriction and butanediol. One cow on treatment 2 developed ketosis, but not fatty liver, after only 4 d of feed restriction. No other cows developed fatty liver or ketosis. Both treatments decreased milk production compared with controls. Feed restriction increased the extent of negative energy balance and caused transient increases in concentrations of NEFA, acetate, and beta-hydroxybutyrate in plasma. Concentrations of beta-hydroxybutyrate and insulin in plasma were increased by butanediol, which is a potent ketone body precursor. Concentration of glycogen in liver was less in feed-restricted cows, whereas glycogen and total lipid were greater in cows given butanediol separately. Gluconeogenic capacity of liver slices was not different among groups. Addition of 1,3-butanediol to in vitro incubation media decreased oxidation of propionate to CO2. Neither feed restriction nor dietary 1,3-butanediol as separate treatments induced the fatty liver and ketosis observed in earlier experiments in which the two treatments were given together.  相似文献   
150.
The microstructure, average grain size, and density of Mg-PSZ sintered with SrO and SiO2 additions are found to depend on the partial pressure of oxygen in the sintering atmosphere. Over the range of 10−1 to 10° atm, both the average grain size and the density increase with oxygen partial pressure, for a constant SrO/SiO2 ratio. The partial pressure of oxygen also affects the microstructural distribution of the remnant liquid phase. At high partial pressures the liquid phase is uniformly distributed, whereas at lower oxygen pressures it is preferentially located near the surface. It is proposed that the microstructure produced by sintering is the result of a competition between liquid-phase-enhanced densification and the migration of the liquid phase to the free surface. The migration is attributed to vaporization of MgO from the liquid phase which increases with decreasing partial pressure of oxygen.  相似文献   
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