Reduced exercise tolerance in CHF may be related to factors other than impaired skeletal muscle oxidative capacity

Background : We sought to determine whether skeletal muscle oxidative capacity, fiber type proportions, and fiber size, capillary density or muscle mass might explain the impaired exercise tolerance in chronic heart failure (CHF). Previous studies are equivocal regarding the maladaptations that occur in the skeletal muscle of patients with CHF and their role in the observed exercise intolerance.

Methods and results : Total body O₂ uptake (VO_2peak) was determined in 14 CHF patients and 8 healthy sedentary similar-age controls. Muscle samples were analyzed for mitochondrial adenosine triphosphate (ATP) production rate (MAPR), oxidative and glycolytic enzyme activity, fiber size and type, and capillary density. CHF patients demonstrated a lower VO_2peak (15.1±1.1 versus 28.1±2.3 mL·kg⁻¹·min⁻¹, P<.001) and capillary to fiber ratio (1.09±0.05 versus 1.40±0.04; P<.001) when compared with controls. However, there was no difference in capillary density (capillaries per square millimeter) across any of the fiber types. Measurements of MAPR and oxidative enzyme activity suggested no difference in muscle oxidative capacity between the groups.

Conclusions : Neither reductions in muscle oxidative capacity nor capillary density appear to be the cause of exercise limitation in this cohort of patients. Therefore, we hypothesize that the low VO_2peak observed in CHF patients may be the result of fiber atrophy and possibly impaired activation of oxidative phosphorylation.

The mathematical and science skills of students who are deaf or hard of hearing educated in inclusive settings

This study examined the science and mathematics achievements of 16 Year 9 students with hearing loss in an inclusive high-school setting in Western Australia. Results from the Monitoring Standards in Education (MSE) compulsory state tests were compared with state and class averages for students with normal hearing. Data were collected from three cohorts of Year 9 students across a 3-year period (2005‐2007). Results from mathematics MSE9 and the MSE9 science assessments showed that the majority of students with hearing loss performed below the state average (88%). Findings in this study suggest that students with hearing loss demonstrated more mathematical strength in the areas of space and measurement, which use visuo-spatial skills. Results for students with hearing loss in the five sections of the science assessment suggest more consistency across the different areas tested in the MSE. Comparisons with the MSE9 English paper for the 2005 cohort of students with hearing loss suggest a strong relationship between reading and writing skills and performance on mathematics and science assessment. In particular, questions with high language content created difficulty. On the science assessment, questions requiring a written explanation appeared to be particularly challenging. These findings have implications for teaching and learning in these crucial areas for students with hearing loss in inclusive secondary school settings. Greater attention to the interpretation of the language of mathematics and to writing about science concepts may help to improve outcomes for students with hearing loss on statewide assessments

Methodological challenges to research among Chinese : using mixed methods to investigate older persons with depression in Macau

The article offers an example of using a mixed methods design that was implemented when investigating depression among Chinese older persons in Macau. A challenge in designing the study was that in light of literature on Chinese culture and somatization theory, the acceptability of the methodology was uncertain. Participants (n = 31) were purposively selected and quantitative data were collected using multiple standardized measures. Questions raised by the quantitative approach were then reflected through in-depth interviews. Four dominant categories emerged: (a) negative thinking, (b) physical limitations and complaints, (c) present living conditions and social support, and (d) the lives participants have lived. There was a high level of congruence between quantitative scores and narratives. The research approach was acceptable to the participants, and the findings contributed to an understanding of depression and therapeutic interventions for that population within Chinese culture.

A Smartphone-based obstacle sensor for the visually impaired

In this paper, we present a real-time obstacle detection system for the mobility improvement for the visually impaired using a handheld Smartphone. Though there are many existing assistants for the visually impaired, there is not a single one that is low cost, ultra-portable, non-intrusive and able to detect the low-height objects on the floor. This paper proposes a system to detect any objects attached to the floor regardless of their height. Unlike some existing systems where only histogram or edge information is used, the proposed system combines both cues and overcomes some limitations of existing systems. The obstacles on the floor in front of the user can be reliably detected in real time using the proposed system implemented on a Smartphone. The proposed system has been tested in different types of floor conditions and a field trial on five blind participants has been conducted. The experimental results demonstrate its reliability in comparison to existing systems.

Portable form filling assistant for the visually impaired

The filling of printed forms has always been an issue for the visually impaired. Though optical character recognition technology has helped many blind people to ‘read’ the world, there is not a single device that allows them to fill out a paper-based form without a human assistant. The task of filling forms is however an essential part of their daily lives, for example, for access to social security or benefits. This paper describes a solution that allows a blind person to complete paper-based forms, pervasively and independently, using only off-the-shelf equipment including a Smartphone, a clipboard with sliding ruler, and a ballpoint pen. A dynamic color fiduciary (point of reference) marker is designed so that it can be moved by the user to any part of the form such that all regions can be “visited”. This dynamic color fiduciary marker is robust to camera focus and partial occlusion, allowing flexibility in handling the Smartphone with embedded camera. Feedback is given to the blind user via both voice and tone to facilitate efficient guidance in filling out the form. Experimental results have shown that this prototype can help visually impaired people to fill out a form independently.

The cost-effectiveness of universal newborn screening for bilateral permanent congenital hearing impairment : systematic review

Objective - Universal newborn hearing screening for bilateral permanent congenital hearing impairment is standard practice in many developed economies, but until there is clear evidence of cost-effectiveness, it remains a controversial use of limited health care resources. We conducted a formal systematic review of studies of newborn hearing screening that considered both costs and outcomes to produce a summary of the available evidence and to determine whether there was a need for further research.

Methods - A search was conducted of medical and nursing databases and gray literature websites by the use of multiple keywords. The titles and abstracts of studies were examined for preliminary inclusion if reference was made to newborn hearing screening, and to both costs and outcomes. Studies of potential relevance were independently assessed by 2 health economists for final inclusion in the review. Studies that met inclusion criteria were appraised by the use of existing guidelines for observational studies, economic evaluations and decision analytic models, and reported in a narrative literature review.

Results - There were 22 distinct observational or modeled evaluations of which only 2 clearly compared universal newborn hearing screening to risk factor screening for bilateral permanent congenital hearing impairment. Of these, the single evaluation that examined long-term costs and outcomes found that universal newborn hearing screening could be cost-saving if early intervention led to a substantial reduction in future treatment costs and productivity losses.

Conclusions - There are only a small number of economic evaluations that have examined the long-term cost-effectiveness of universal newborn hearing screening. This is partly attributable to ongoing uncertainty about the benefits gained from the early detection and treatment of bilateral permanent congenital hearing impairment. There is a clear need for further research on long-term costs and outcomes to establish the cost-effectiveness of universal newborn hearing screening in relation to other approaches to screening, and to establish whether it is a good long term investment.