A comparison of GaAs HJBT and silicon bipolar technologies forhigh-speed analog-to-digital converters

The potential using the emerging GaAlAs/GaAs heterojunction bipolar transistor (HJBT) technology is all-parallel analog-to-digital (A/D) converters is studied. To put into perspective the HJBT predictions made, a comparison of the ultimate performance levels achievable with contemporary silicon bipolar processes is given. Optimized latched compensators were developed for each technology and simulations on SPICE were carried out to determine the maximum sample rate and large-signal analog bandwidths that would be achieved. As both technologies are produced in-house, models were available for processors in the latter stages of development, namely the standard 1-μm silicon bipolar process, and the 4-μm HJBT process, as well as processes at an earlier stage of development, the enhanced 1-μm silicon bipolar processes and the 2.5-μm HJBT process. This enabled the trend of performance improvements with time to be compared     

Open heart operation in patients suffering from hereditary spherocytosis

Hereditary spherocytosis is a clinically heterogeneous, genetically determined red blood cell membrane disorder resulting in hemolytic anemia. Structural or functional disorders of the cytoskeletal proteins result in the formation of spherocytes, which lack the strength, durability, and flexibility to withstand the stresses of the circulation. This problem can be accentuated by the deleterious effects of the heart-lung machine. Three patients with hereditary spherocytosis underwent open heart operation with no deaths and no serious complications resulting from the hematologic defect. Splenectomy is recommended, although not essential, before a cardiac operation, and mechanical valves should perhaps be avoided.     

Psychosocial characteristics of inner-city children with asthma: a description of the NCICAS psychosocial protocol. National Cooperative Inner-City Asthma Study

Previous research has demonstrated a significant reciprocal relationship between psychosocial factors and asthma morbidity in children. The National Cooperative Inner-City Asthma Study investigated both asthma-specific and non-specific psychosocial variables, including asthma knowledge beliefs and management behavior, caregiver and child adjustment, life stress, and social support. This article presents these psychosocial characteristics in 1,528 4-9-year-old asthmatic urban children and their caretakers. Caretakers demonstrated considerable asthma knowledge, averaging 84% correct responses on the Asthma Information Quiz. However, respondents provided less than one helpful response for each hypothetical problem situation involving asthma care, and most respondents had more than one undesirable response, indicating a potentially dangerous or maladaptive action. Both adults and children reported multiple caretakers responsible for asthma management (adult report: average 3.4, including the child); in addition, children rated their responsibility for self-care significantly higher than did adults. Scores on the Child Behavior Checklist indicated increased problems compared to normative samples (57.3 vs. 50, respectively), and 35% of children met the criteria for problems of clinical severity. On the Brief Symptom Inventory, adults reported elevated levels of psychological distress (56.02 vs norm of 50); 50% of caretakers had symptoms of clinical severity. Caretakers also experienced an average of 8.13 undesirable life events in the 12 months preceding the baseline interview. These findings suggest that limited asthma problem-solving skills, multiple asthma managers, child and adult adjustment problems, and high levels of life stress are significant concerns for this group and may place the inner-city children in this study population at increased risk for problems related to adherence to asthma management regimens and for asthma morbidity.     

Congenital superficial angiomyxoma

Superficial angiomyxomas are rare, benign, dermal and subcutaneous tumours. We describe a 12-year-old girl who presented with a nodular swelling in the midline of her scalp that had been present since birth. Histological examination revealed an ill-defined myxoid lesion within the dermis, comprising spindle cells, blood vessels and occasional multi-nucleate giant cells. Immunohistochemical staining was negative for S-100, cytokeratin and smooth muscle actin, but focally positive for CD34. Our patient is unusual in that the angiomyxoma was present at birth, which has not previously been described. The importance of screening patients with cutaneous myxomas for cardiac lesions is discussed.     

Child diagnostic assessment: Current training practices in clinical psychology internships.

Surveyed clinical psychology internships regarding current practices in training child diagnostic assessment: proportion of interns' time spent in child vs adult experiences, child assessment vs other types of child experiences, and didactic vs direct clinical experience. We compared the responses from general clinical psychology internships with those identifying themselves as child specialty internships. The percentage of child-related experience (39%) was higher for general internships than was the percentage of adult-related experience (14%) for child specialty internships. Although there were more similarities than differences across types of programs, trainees from general internships reported significantly less experience in assessment of younger children, particularly preschool age, and both groups reported only minimal assessment experience with infants. Although moderate training experiences were reported with traditional assessment instruments, both groups reported minimal experience with the more specialized ability assessment of exceptional children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

FORECASTS FROM THE EMPLOYMENT BLOCK OF A MULTI-SECTORAL MODEL OF THE SCOTTISH ECONOMY

ABSTRACT This paper considers the determination of employment in four Scottish industries. The specifications considered are classified as either Keynesian or neoclassical in nature by reference to the relevant economic theory. The statistical assessment of an estimated equation involves the calculation of a number of diagnostic test statistics which assess, amongst other things, the accuracy of the forecasts produced by the equation. To distinguish between alternative estimated equations we employ non-nested (or separate) test procedures. The results obtained suggest Keynesian type specifications are superior for three of the four industries considered.     

On the statistical physics of radial basis function networks

Techniques from statistical physics have been applied successfully in recent years to the analysis of the generalization performance of neural networks. However, most of the analysis to date has been for perceptron-like networks or simple generalizations thereof such as committee machines, and none of the networks studied are used to any significant extent in practice. This letter presents results obtained in applying techniques from statistical physics to a popular class of neural networks that has been used successfully in many practical applications: the Gaussian radial basis function networks. We obtain expressions for the learning curves exhibited by these networks in the high-temperature limit for both realizable and unrealizable target rules.     

How should Fitts' Law be applied to human-computer interaction?

The paper challenges the notion that any Fitts' Law model can be applied generally to human-computer interaction, and proposes instead that applying Fitts' Law requires knowledge of the users' sequence of movements, direction of movement, and typical movement amplitudes as well as target sizes. Two experiments examined a text selection task with sequences of controlled movements (point-click and point-drag). For the point-click sequence, a Fitt's Law model that used the diagonal across the text object in the direction of pointing (rather than the horizontal extent of the text object) as the target size provided the best fit for the pointing time data, whereas for the point-drag sequence, a Fitts' Law model that used the vertical size of the text object as the target size gave the best fit. Dragging times were fitted well by Fitts' Law models that used either the vertical or horizontal size of the terminal character in the text object. Additional results of note were that pointing in the point-click sequence was consistently faster than in the point-drag sequence, and that pointing in either sequence was consistently faster than dragging. The discussion centres around the need to define task characteristics before applying Fitts' Law to an interface design or analysis, analyses of pointing and of dragging, and implications for interface design.     

Optimized partial-coverage functional analysis pipeline (OPFAP): a semi-automated pipeline for skull stripping and co-registration of partial-coverage,ultra-high-field functional images

Objective

Ultra-high-field functional MRI (UHF-fMRI) allows for higher spatiotemporal resolution imaging. However, higher-resolution imaging entails coverage limitations. Processing partial-coverage images using standard pipelines leads to sub-optimal results. We aimed to develop a simple, semi-automated pipeline for processing partial-coverage UHF-fMRI data using widely used image processing algorithms.

Materials and methods

We developed automated pipelines for optimized skull stripping and co-registration of partial-coverage UHF functional images, using built-in functions of the Centre for Functional Magnetic Resonance Imaging of the Brain's (FMRIB’s) Software library (FSL) and advanced normalization tools. We incorporated the pipelines into the FSL’s functional analysis pipeline and provide a semi-automated optimized partial-coverage functional analysis pipeline (OPFAP).

Results

Compared to the standard pipeline, the OPFAP yielded images with 15 and 30% greater volume of non-zero voxels after skull stripping the functional and anatomical images, respectively (all p =?0.0004), which reflected the conservation of cortical voxels lost when the standard pipeline was used. The OPFAP yielded the greatest Dice and Jaccard coefficients (87 and 80%, respectively; all p <?0.0001) between the co-registered participant gyri maps and the template gyri maps, demonstrating the goodness of the co-registration results. Furthermore, the greatest volume of group-level activation in the most number of functionally relevant regions was observed when the OPFAP was used. Importantly, group-level activations were not observed when using the standard pipeline.

Conclusion

These results suggest that the OPFAP should be used for processing partial-coverage UHF-fMRI data for detecting high-resolution macroscopic blood oxygenation level-dependent activations.