用ePCI-X使设计现代化

从PCI/ISA到双总线ePCI-X, 一种设计重用方法 　　在当今的PCI/ISA背板中,显然PC芯片组ISA插槽的数量在减少,PCI插槽的数量在增多.……     

Hereditary exostoses--presentation of a family case

In this article we present a Norwegian family with hereditary multiple exostoses and a review of relevant literature. 21 family members were examined; ten males and six females had multiple exostoses, the youngest from six months of age. The exostoses had led to compression of nerves, disturbance of bone growth with shortening and bowing of the forearm bones, and valgus deformity of the knee and ankle. Physical function and quality of life was generally well preserved. Contrary to most reports, nearly half of the patients had allegedly noticed growth or debut of exostoses in adulthood. Almost half of the patients had had the exostoses removed surgically twice, (median value). Malignant transformation of exostoses has not been observed in the family.     

Liver failure associated with mitochondrial DNA depletion

BACKGROUND/AIMS: Liver failure in infancy can result from several disorders of the mitochondrial respiratory chain. In some patients, levels of mitochondrial DNA are markedly reduced, a phenomenon referred to as mitochondrial DNA depletion. To facilitate diagnosis of this condition, we have reviewed the clinical and pathological features in five patients with mitochondrial DNA depletion. METHODS: Cases were identified by preparing Southern blots of DNA from muscle and liver, hybridising with appropriate probes and quantifying mitochondrial DNA relative to nuclear DNA. RESULTS: All our patients with mitochondrial DNA depletion died of liver failure. Other problems included hypotonia, hypoglycaemia, neurological abnormalities (including Leigh syndrome) and cataracts. Liver histology showed geographic areas of fatty change, bile duct proliferation, collapse of liver architecture and fibrosis; some cells showed decreased cytochrome oxidase activity. Muscle from three patients showed mitochondrial proliferation, with loss of cytochrome oxidase activity in some fibres but not in others; in these cases, muscle mitochondrial DNA levels were less than 5% of the median control value. The remaining two patients (from a single pedigree) had normal muscle histology and histochemistry associated with less severe depletion of mitochondrial DNA in muscle. CONCLUSIONS: Liver failure is common in patients with mitochondrial DNA depletion. Associated clinical features often include neuromuscular disease. Liver and muscle histology can be helpful in making the diagnosis. Mitochondrial DNA levels should be measured whenever liver failure is thought to have resulted from respiratory chain disease.     

An investigation of handheld device use by older adults with age-related macular degeneration

This study investigates factors affecting handheld human - computer interaction (HCI) for older adults with Age-related Macular Degeneration (AMD). This is largely an uncharted territory, as empirical investigations of HCI concerning users with visual dysfunction and/or older adults have focused primarily on desktop computers. For this study, participants with AMD and visually healthy controls used a handheld computer to search, select and manipulate familiar playing card icons under varied icon set sizes, inter-icon spacing and auditory feedback conditions. While all participants demonstrated a high rate of task completion, linear regression revealed several relationships between task efficiency and the interface, user characteristics and ocular factors. Two ocular measures, severity of AMD and contrast sensitivity, were found to be highly predictive of efficiency. The outcomes of this work reveal that users with visual impairments can effectively interact with graphical user interfaces on small displays in the presence of low-cost, easily implemented design interventions. Furthermore, results demonstrate that the detrimental influence of AMD and contrast sensitivity on handheld technology interaction can be offset by such interventions. This study presents a rich data set and is intended to inspire future work characterizing and modeling the interactions of individuals with visual impairments with non-traditional information technology platforms and contexts.     

Social problem solving and community integration in postacute rehabilitation outpatients with traumatic brain injury.

Objective: To enhance understanding of the role that social problem solving (SPS) plays in community integration following traumatic brain injury (TBI). Study Design: Regression analysis. Participants: Forty-five adults with TBI participating in higher level outpatient cognitive rehabilitation and 15 uninjured adults. Main Outcome Measures: Measures of community integration, problem-solving ability, and SPS self-appraisal and performance. Results: Individuals with TBI demonstrated poorer problem-solving as measured by both neuropsychological and SPS methods; however, the largest effect' size was observed for SPS self-appraisal. Only SPS self-appraisal predicted a significant proportion of the variance in community integration. Conclusions: It is important to assess brain-injured persons' confidence in their ability to cope with problems. A focus on objective test scores alone may lead to underdetection of disabling problem-solving deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A temperature-dependent model for the complex dielectric function of GaAs

In this work, we discuss a temperature-dependent model for the complex dielectric function for GaAs valid for the temperature range 31°C ≤ T ≤ 634°C. We describe our model, which is an extension of the critical point parabolic band method. This is a phenomenological method which is based on the physical processes occurring in the semiconductor, and has been previously demonstrated for composition-dependent models of the dielectric function for lattice-matched materials systems. We demonstrate the quality of the model in fitting optical data for individual temperatures, and compare our results to other established models. The data used for each fitting ranges from 1.25 to 4.5 eV. Using results obtained from the individual fits, we generate a temperature-dependent model that is valid for the range of temperatures given above. Also, we show how this model can be used to accurately determine the temperature (±2.3°C) of a material whose dielectric response has been obtained but was not included when generating the model.     

Effects of ratee task performance and interpersonal factors on supervisor and peer performance ratings.

The study examines the effects of a wide array of rater–ratee relationship and ratee-characteristic variables on supervisor and peer job-performance ratings. Interpersonal ratings, job performance ratings, and ratee scores on ability, job knowledge, and technical proficiency were available for 493 to 631 first-tour US Army soldiers. Results of supervisor and peer ratings-path models showed ratee ability, knowledge, and proficiency accounted for 13% of the variance in supervisor performance ratings and 7% for the peer ratings. Among the interpersonal variables, ratee dependability had the strongest effect for both models. Ratee friendliness and likability had little effect on the performance ratings. Inclusion of the interpersonal factors increased the variance accounted for in the ratings to 28% and 19%, respectively. Discussion focuses on the relative contribution of ratee technical and contextual performance to raters' judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The cognitive, subjective, and physical effects of a ginkgo biloba/panax ginseng combination in healthy volunteers with neurasthenic complaints

We evaluated the effects of a Ginkgo biloba/ginseng combination on cognitive function in this 90-day, double-blind, placebo-controlled, parallel-group study. Sixty-four healthy volunteers (aged 40 to 65 years), selected on the basis of fulfilling the ICD-10 F48.0 criteria for neurasthenia, were assigned randomly to four equal dosing groups, receiving 80, 160, or 320 mg of the combination b.i.d. or placebo. Assessments were performed on the day before dosing, and again at Days 1, 30, and 90 at 1 hour after the morning dose and 1 hour after the afternoon dose. The assessments included the Cognitive Drug Research (CDR) computerized assessment system, the Vienna Determination Unit, cycle ergometry, and various questionnaires. The treatments were well tolerated by all volunteers. On Day 90 at 1 hour post morning dosing, dose-related improvements were seen on the CDR tests, the 320 mg dose being significantly superior to placebo. These effects, however, were reversed 1 hour after the afternoon dose, possibly suggesting that a longer inter-dosing interval would be preferable. The 80-mg dose produced a significant benefit on the ergometry assessment of heart rate at maximum load. There were also several supporting changes from other assessments, including an advantage of 320 mg over placebo on the global score from the Symptom Checklist-90-revised (SCL-90-R) at Day 90.     

Low temperature growth of AIGaP and GaP on si substrates by atomic layer epitaxy

AIGaP and GaP films were deposited on the (100) Si substrates by atomic layer epitaxy (ALE) in the temperature range between 450 and 600°C. Under optimum growth conditions, the growth of GaP and AIGaP was observed to proceed in a two-dimensional (2-D) fashion in the initial growth stages. These ALE-grown films have better surface morphology when compared with the corresponding MOCVD-grown films. With an AIGaP buffer layer grown on Si, the subsequent growth of GaAs on the AlGaP-coated Si substrates tends to proceed as 2-D growth. This avoids island growth and the two-step growth process currently used.