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931.
This study aimed to explore the lived experience of assuming the primary caregiver role in a group of spouses of individuals living with a traumatic spinal cord injury (SCI) (injuries ranged from paraplegia to quadriplegia). Individual in-depth interviews were conducted with 11 participants who were both the spouse and primary caregiver of an individual with a SCI; of these, 10 were female and 1 was male. All interviews were transcribed verbatim and were subjected to interpretative phenomenological analysis (IPA). Here we present three inter-related master themes: ‘The emotional impact of SCI’; ‘Post-injury shift in relationship dynamics’ and ‘Impact of caregiving on identity’. Regarding the emotional impact of spinal injury, participants reported an almost instantaneous sense of loss, emptiness and grief during the injured person's rehabilitative period and feelings of anxiety were reported in anticipation of their return to the family home. A distinct change in role from spouse and lover to care provider was reported and this ultimately contributed to relationship change and a loss of former identity. The findings are discussed in relation to extant caregiver literature and recommendations for future caregiver support are highlighted.  相似文献   
932.
Both positive and negative changes are commonly reported by cancer survivors, and both may impact quality of life. Yet few studies have directly compared the associations of positive and negative changes across multiple life domains with multiple aspects of well-being. This study examined positive and negative changes and their conjoint relation to a range of well-being indices. We used correlational and regression analyses of data from 237 young to middle aged (X?=?45.3?years) cancer survivors, several years after treatment. Measures included demographic and medical variables, medical post-cancer positive and negative changes on multiple life domains, and a range of positive and negative adjustment indices. Demographic factors, especially income, related to both positive and negative outcomes. On average, participants reported no change on most life domains, although modest amounts of both positive and negative changes were reported. Negative change, rather than positive change, was closely associated with cancer survivors’ adjustment. Detailed measurement of both positive and negative changes – as well as lack of change – is important to advance understanding of cancer's impact on survivors.  相似文献   
933.
When Klein, W. M. gave participants absolute and comparative risk information (crossed experimentally) they were more disturbed by being above than below average, but not by being at higher rather than lower risk. The current experiment tests whether Klein's findings extend to situations involving lower risk figures more typical of genuine health risks, assesses participants’ understanding of the information, and directly compares responses of US and UK samples. Participants were presented with hypothetical information about comparative and absolute risks of deep vein thrombosis. There was a main effect of absolute risk information on disturbance and precaution intentions in the US sample, but no effects of comparative information on these measures in either sample. Understanding was poor among participants receiving both pieces of risk information. Future studies should include measures of understanding to establish whether people are failing to understand what they are told or failing to respond systematically to what they understand. Practically, the findings caution against providing comparative risk information when communicating low risk figures.  相似文献   
934.
It has been hypothesized that a local processing bias underlies overall visuospatial impairments in Williams syndrome (WS). However, recent studies have challenged this hypothesis by providing evidence against a local processing bias at the perceptual level. The aim of the present study was to further examine drawing and perceptual skills in children with WS using closely matched-hierarchical stimuli. In the drawing task children with WS exhibited a local processing bias. However, no significant preferential bias was found in the perceptual task. This indicates that children with WS do not systematically present a preferential bias for local information. Taken together the findings of the present study suggest that perceptual processing deficits per se are unlikely to explain local processing biases in visuoconstructive tasks often described in people with WS.  相似文献   
935.
936.
The present study examined verbal and spatial learning and memory in children and adolescents who had undergone unilateral temporal lobectomy versus controls. All participants were trained to criterion before a delay to assess learning efficiency. There were no significant differences between the groups in rate of learning the verbal task. The right temporal-lobe group, but not the left, had difficulty learning spatial information. These findings indicate a specific effect of early right temporal-lobe lesions on spatial learning. As material-specificity is more often found in adults for verbal information, the present results highlight the unique role of the temporal-lobe in development.  相似文献   
937.
Over the past three decades, perinatal HIV infection in the United States has evolved from a fatal disease to a manageable chronic illness. As the majority of youth with perinatal HIV infection age into adolescence and adulthood, management of this stigmatizing, transmittable disease in the backdrop of a cadre of environmental stressors presents challenges beyond those of other chronic illnesses. The neurologic and neuropsychological consequences of this neurotropic virus have important implications for the successful navigation of responsibilities related to increasingly independent living of this aging population. This article will review the neurologic and neuropsychological consequences of perinatal HIV infection and concomitant factors in the era of highly active antiretroviral therapy and will provide an overview of the neuropathology, pathogenesis, neuroimaging findings, and treatment of perinatal HIV infection, as well as recommendations for service provision and future research.  相似文献   
938.
The partitioning of the trace element Sn into Cu-rich precipitates in a low-alloy pressure-vessel steel has been characterized using the three-dimensional atom probe (3DAP) technique. This investigation has revealed for the first time that the trace element Sn, present at only 0.007?at.% in the steel, partitions strongly to both small spherical precipitates (<4?nm in diameter) and to large non-spherical precipitates (largest dimension 10–50?nm) during thermal ageing. Sn was also seen to segregate strongly to the precipitate/matrix interface of a large Cu precipitate and particularly in the region where a dislocation appears to intersect the precipitate. The strong attraction of large solute atoms to special sites probably drives the interfacial segregation of Sn. This is consistent with the observation of stronger segregation of Sn to the interface of large precipitates than to the coherent interface of smaller precipitates.  相似文献   
939.
Antiplane shear cracks in a harmonic square lattice have been studied in a molecular dynamics simulation. They can reach velocities larger than the shear wave velocity.  相似文献   
940.

The nature of impurity-dislocation interactions is one of the key questions governing the strength and plasticity of solid-solution materials. To investigate the influence of impurities on the mechanical properties of intermetallic NiAl, the electronic structure and energy of NiAl with a <100>{010} edge dislocation and transition-metal impurities was calculated using the real-space tight-binding linear muffin-tin orbital method. The localized electronic states, appearing in the core of the dislocation, are found to lead to strong impurity-dislocation interactions via two mechanisms: firstly, chemical locking, due to strong hybridization between impurity electronic states and dislocation localized states; secondly, electrostatic locking, due to long-range charge oscillations caused by the electron localization in the dislocation core. The results obtained explain qualitatively why the solid-solution hardening effect in NiAl correlates with the electronic structure of impurities rather than with size misfit, as expected according to traditional views.  相似文献   
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