Reconsidering management for otitis media with effusion in children

Otitis media is the most commonly diagnosed illness apart from the common cold and treatment by insertion of tympanoplasty tubes is the most frequent operation in children beyond the neonatal period. Approximately nine in every ten children have had at least one episode by the age of two years and figures for South Africa may even be higher. Recent research findings have led to a more conservative approach to treatment of otitis media with effusion as opposed to previous recommendations for prompt insertion of tympanostomy tubes to avoid suspected developmental delays due to the mild conductive hearing loss. A large scale longitudinal clinical trial has demonstrated that prompt versus delayed insertion of tympanostomy tubes does not affect developmental outcomes and therefore a conservative approach of monitoring the condition and hearing status alongside speech and language development is recommended without the use of medication as routine management. These recommendations may ultimately result in significant healthcare savings for South Africa but must be implemented within a collaborative team approach to ensure developmental outcomes are not compromised due to poor surveillance. South African Family Practice Vol. 49 (7) 2007: pp.

A new approach to evaluate gamma-ray measurements

Misunderstandings about the term random samples its implications may easily arise. Conditions under which the phases, obtained from arrival times, do not form a random sample and the dangers involved are discussed. Watson's U sup 2 test for uniformity is recommended for light curves with duty cycles larger than 10%. Under certain conditions, non-parametric density estimation may be used to determine estimates of the true light curve and its parameters

Computer and internet interventions to optimize listening and learning for people with hearing loss: accessibility, use, and adherence

Purpose: The aim of this research forum article was to examine accessibility, use, and adherence to computerized and online interventions for people with hearing loss. Method: Four intervention studies of people with hearing loss were examined: 2 auditory training studies, 1 working memory training study, and 1 study of multimedia educational support. Results: A small proportion (approximately 15%) of participants had never used a computer, which may be a barrier to the accessibility of computer and Internet based interventions. Computer competence was not a factor in intervention use or adherence. Computer skills and Internet access influenced participant preference for the delivery method of the multimedia educational support program. Conclusions: It is important to be aware of current barriers to computer and Internet-delivered interventions for people with hearing loss. However, there is a clear need to develop and future-proof hearing-related applications for online delivery

On the multiple Borsuk numbers of sets

The Borsuk number of a set S of diameter d >0 in Euclidean n-space is the smallest value of m such that S can be partitioned into m sets of diameters less than d. Our aim is to generalize this notion in the following way: The k-fold Borsuk number of such a set S is the smallest value of m such that there is a k-fold cover of S with m sets of diameters less than d. In this paper we characterize the k-fold Borsuk numbers of sets in the Euclidean plane, give bounds for those of centrally symmetric sets, smooth bodies and convex bodies of constant width, and examine them for finite point sets in the Euclidean 3-space.Comment: 16 pages, 3 figure

Thermally Induced Nano-Structural and Optical Changes of nc-Si:H Deposited by Hot-Wire CVD

We report on the thermally induced changes of the nano-structural and optical properties of hydrogenated nanocrystalline silicon in the temperature range 200–700 °C. The as-deposited sample has a high crystalline volume fraction of 53% with an average crystallite size of ~3.9 nm, where 66% of the total hydrogen is bonded as ≡Si–H monohydrides on the nano-crystallite surface. A growth in the native crystallite size and crystalline volume fraction occurs at annealing temperatures ≥400 °C, where hydrogen is initially removed from the crystallite grain boundaries followed by its removal from the amorphous network. The nucleation of smaller nano-crystallites at higher temperatures accounts for the enhanced porous structure and the increase in the optical band gap and average gap

Systematic review of vestibular disorders related to human immunodeficiency virus and acquired immunodeficiency syndrome

INTRODUCTION: Disorders of the auditory and vestibular system are often associated with human immunodeficiency virus infection and acquired immunodeficiency syndrome. However, the extent and nature of these vestibular manifestations are unclear. OBJECTIVE: To systematically review the current peer-reviewed literature on vestibular manifestations and pathology related to human immunodeficiency virus and acquired immunodeficiency syndrome. METHOD: Systematic review of peer-reviewed articles related to vestibular findings in individuals with human immunodeficiency virus infection and acquired immunodeficiency syndrome. Several electronic databases were searched. RESULTS: We identified 442 records, reduced to 210 after excluding duplicates and reviews. These were reviewed for relevance to the scope of the study. DISCUSSION: We identified only 13 reports investigating vestibular functioning and pathology in individuals affected by human immunodeficiency virus and acquired immunodeficiency syndrome. This condition can affect both the peripheral and central vestibular system, irrespective of age and viral disease stage. Peripheral vestibular involvement may affect up to 50 per cent of patients, and central vestibular involvement may be even more prevalent. Post-mortem studies suggest direct involvement of the entire vestibular system, while opportunistic infections such as oto- and neurosyphilis and encephalitis cause secondary vestibular dysfunction resulting in vertigo, dizziness and imbalance. CONCLUSION: Patients with human immunodeficiency virus and acquired immunodeficiency syndrome should routinely be monitored for vestibular involvement, to minimise functional limitations of quality of life.http://journals.cambridge.org/action/displayJournal?jid=JL

An Attribute-Based Approach to Classifying Community-Based Tourism Networks

This conceptual paper proposes the adoption of a collaborative network approach as a prospective means of improving success in implementing community-based tourism (CBT) initiatives. Drawing upon relevant literature, the researchers identify the key attributes that characterise a network-based approach. By proposing alternatives for each attribute, the research provides CBT practitioners with options for making informed decisions about how to build collaboration connecting individual CBT initiatives in multiple locations. The researchers discuss the implications of different approaches for power relations between stakeholders. The proposed framework provides a means of classifying existing CBT networks and analyses the types of network and the circumstances which lead to better outcomes for community development. Further empirical research is required to test the validity of the key network attributes and to develop a comprehensive classification system of CBT networks.School of Hotel and Tourism Managemen

Long-term evidence for ecological intensification as a pathway to sustainable agriculture

Ecological intensification (EI) could help return agriculture into a ‘safe operating space’ for humanity. Using a novel application of meta-analysis to data from 30 long-term experiments from Europe and Africa (comprising 25,565 yield records), we investigated how field-scale EI practices interact with each other, and with N fertilizer and tillage, in their effects on long-term crop yields. Here we confirmed that EI practices (specifically, increasing crop diversity and adding fertility crops and organic matter) have generally positive effects on the yield of staple crops. However, we show that EI practices have a largely substitutive interaction with N fertilizer, so that EI practices substantially increase yield at low N fertilizer doses but have minimal or no effect on yield at high N fertilizer doses. EI practices had comparable effects across different tillage intensities, and reducing tillage did not strongly affect yields