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131.
Although a number of studies suggests a link between working memory (WM) storage capacity of short-term memory and calculation abilities, the nature of verbal WM deficits in children with developmental dyscalculia (DD) remains poorly understood. We explored verbal WM capacity in DD by focusing on the distinction between memory for item information (the items to be retained) and memory for order information (the order of the items within a list). We hypothesized that WM for order could be specifically related to impaired numerical abilities given that recent studies suggest close interactions between the representation of order information in WM and ordinal numerical processing. We investigated item and order WM abilities as well as basic numerical processing abilities in 16 children with DD (age: 8–11 years) and 16 typically developing children matched on age, IQ, and reading abilities. The DD group performed significantly poorer than controls in the order WM condition but not in the item WM condition. In addition, the DD group performed significantly slower than the control group on a numerical order judgment task. The present results show significantly reduced serial order WM abilities in DD coupled with less efficient numerical ordinal processing abilities, reflecting more general difficulties in explicit processing of ordinal information.  相似文献   
132.
Purpose: Pediatric brain tumors are the second most common cancer diagnosis in individuals under age 20 and research has documented significant neurocognitive, psychosocial, and emotional late effects. Associations among these deficits have not been adequately considered and the role of survivors’ coping with stress in relation to deficits is unknown. Further, research has yet to examine neurobiological processes related to neurocognitive, psychosocial, and emotional difficulties in survivors through the use of functional neuroimaging. Method: Questionnaire measures and functional neuroimaging were used to examine the neurocognitive, psychosocial, and emotional functioning and coping responses of survivors of pediatric brain tumors (= 17; age 8–16) and healthy children (= 15). Results: Survivors experienced elevated levels of psychosocial and behavioral/emotional difficulties relative to healthy controls and normative data. Increases in brain activation in prefrontal and other anterior regions in response to a working memory task were associated with better psychosocial functioning, use of engagement coping strategies, and less use of disengagement coping strategies. Regression analyses suggest coping accounts for a significant portion of the association between brain activation and behavioral/emotional functioning. Conclusions: This study extends late-effects research by examining neurobiological processes associated with psychosocial and emotional difficulties. These findings contribute to our understanding of difficulties in survivors and provide a foundation for research exploring these associations and mediators of deficits in future longitudinal studies.  相似文献   
133.
Electropulsing usually promotes a metastable phase to evolve towards its equilibrium state. This work reports an alternative case, where electropulsing promotes the decomposition of the stable δ-phase in duplex stainless steel at high temperature. This decomposition enables both the γ-phase and the σ-phase in the steel to survive and hence to strengthen it at high temperature. The hardness of the quenched sample with electropulsing treatment is 49.4% higher than that without electropulsing treatment. A fundamental understanding of the observation is developed.  相似文献   
134.
High-pressure X-ray diffraction studies on gadolinium sesquioxide (Gd2O3) have been carried out up to a pressure of ~25 GPa in a diamond-anvil cell at room temperature. Gadolinium oxide, which has a cubic or bixbyite structure under ambient conditions, undergoes an irreversible structural phase at around 12 GPa. The high-pressure phase has been identified as a hexagonal La2O3-type structure. The bulk modulus and its pressure derivative of this phase have been calculated.  相似文献   
135.
It is interesting to investigate the formation of He bubbles in amorphous alloys because point defects do not exist in amorphous materials. In the present study, the microstructural evolution of amorphous Fe79B16Si5 alloy, either irradiated with 5?keV He+ ions or implanted with 150?eV He+ ions without causing displacement damage, and then annealed at a high temperature, was investigated using transmission electron microscopy (TEM). Vacancy-type defects were formed in the amorphous alloy after irradiation with 5?keV He+ ions, and He bubbles formed during annealing the irradiated samples at high temperature. On the other hand, for samples implanted with 150?eV He+ ions, although He atoms are also trapped in the free volume, no He bubbles were observed during annealing the samples even up to 873?K. In conclusion, the formation of He bubbles is related to the formation and migration of vacancy-type defects even in amorphous alloys.  相似文献   
136.
This paper examines three central concerns for the short-term therapist at a time when therapy is widely available free of charge in the community, in a model that has been called ‘ serial life-span therapy’. Issues of referral-on, topping-up or extending contracts are experienced as dilemmas or as temptations, depending on what therapists believe their clients need and what their clients may demand of them. Short-term therapy has become accepted in many contexts, with therapy no longer used as a once-and-for all solution to clinical problems, but as a serial method over time which includes topping up and re-contracting. After an initial agreement of brevity, depending on the client's disturbance levels at assessment and on availability, there may be the need for referral-on at the end of a brief contract, when clients may be offered a different, long-term service, or they may be recommended to return later in life for more, if and when this becomes necessary. Flexible contracts rather than rigid rules about the termination of therapy are being practiced in many contexts, depending on ‘what works’ and how methods can be adjusted to new evidence. There is danger of collusion or control, and this can lead to therapeutic dilemmas, which involve taking acceptable risks, or to therapeutic temptations, which are due to the desire for narcissistic gratification, benefiting the therapist rather than the client in terms of power or Eros. Being able to let go of clients and manage issues of loss, grief and greed requires a measure of maturity in the therapist that aims for good-enough results rather than striving for perfect endings.  相似文献   
137.
Abstract

The few published psychoanalytic writings that exist regarding transsexual men and women tend to focus on the etiology of their gender identities and almost invariably define these patients as inherently pathological. Such myopic viewpoints leave no room for analysis and discussion of the transsexual patient's normal developmental process. In this paper, I use a Kleinian framework to depathologize the coping strategies employed by transsexual patients and to illustrate the importance of mourning in the development of a positive transsexual identity. A clinician who is able to sit comfortably with contradiction may facilitate the transsexual patient's mourning process—saying goodbye to the persecutory object of the past and letting go of the idealized image of the future.  相似文献   
138.
139.
It is essential that outcome research permit clear conclusions to be drawn about the efficacy of interventions. The common practice of nesting therapists within conditions can pose important methodological challenges that affect interpretation, particularly if the study is not powered to account for the nested design. An obstacle to the optimal design of these studies is the lack of data about the intraclass correlation coefficient (ICC), which measures the statistical dependencies introduced by nesting. To begin the development of a public database of ICC estimates, the authors investigated ICCs for a variety outcomes reported in 20 psychotherapy outcome studies. The magnitude of the 495 ICC estimates varied widely across measures and studies. The authors provide recommendations regarding how to select and aggregate ICC estimates for power calculations and show how researchers can use ICC estimates to choose the number of patients and therapists that will optimize power. Attention to these recommendations will strengthen the validity of inferences drawn from psychotherapy studies that nest therapists within conditions.  相似文献   
140.
The present study suggests a modelling methodology for examining measurement invariance of ordered categorical item indicators of latent constructs such as anxiety, coping, motives etc., in research settings with few subgroups and a large sample of individuals. The Hungarian version of the Anxiety Trait scale of the State-Trait Anxiety Inventory for Children (STAIC-H) was administered to 605 boys and 975 girls of age 10–15 in 12 schools. A MIMIC model was suggested for examining measurement invariance across subgroups of schools and ages, while a multi-group analysis was recommended for investigating invariance across gender. High degree of invariance across groups was obtained for the Anxiety Trait scale in terms of item factor loadings, item thresholds and item homogeneity with respect to group contrast variables. Based on the diagnostic information obtained by the present methodology, the few item indicators showing non-invariance were discussed with reference to methodological and conceptual considerations.  相似文献   
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