Assisting the autistic To reduce anxiety caused by their environment

Many people with Autistic Spectrum Disorder (ASD) find certain sounds so unpleasant that their lifestyle can be severely impaired by the need to avoid these noises. This paper considers several common sources of such anxietyinducing noise in the normal home and working environments, and considers whether this problem could be addressed with mechatronic concepts. People with ASD were tested for their reactions to a range of noises, and to the same noises filtered through noise reduction devices. Analysis of the probable characteristics of the anxiety- causing noise features was made. The noises were varying in time and pitch. In addition to anecdotal and survey evidence some carefully structured tests were carried out on some participants using the devices. Based on this investigation, specific mechatronic devices are proposed, using active noise control to selectively soften the sounds, which may be suitably used by those suffering ASD. A smart home or office could deploy multiple devices, in the optimal locations to reduce any offensive noise, whilst preserving a pleasant environment that allows the user the ability to communicate. Furthermore the environment could be tuned to the needs of specific individuals, and switched when they are present

Testing medical drills for noise emissions

Copyright @ 2007 TUT PressA comparative study of drills from a range of manufacturers was carried out in the laboratory. These tests were made under a variety of loading conditions to assess the characteristics of the noise likely in the dentist’s surgery. Details of the test setup are given, and some of the issues in analysing the results considered. Simultaneous Recordings were made of the noise on a minidisk recorder, a hand held sound meter, and a sound analyser. The results from these are considered. These are significant for dentist’s hearing, and the patient’s perception of visiting the dentists. The performance of different designs of pneumatic drill varies much with type and load

Active noise control for high frequencies

There are many applications that can benefit from Active Noise Control (ANC) such as in aircraft cabins and air conditioning ducts, i.e. in situations where technology interferes with human hearing in a harmful way or disrupts communication. Headsets with analogue ANC circuits have been used in the armed forces for attenuating frequencies below 1 kHz, which when combined with passive filtering offers protection across the whole frequency range of human hearing. A dental surgery is also a noisy environment; in which dental drill noise is commonly off-putting for many patients and is believed to harm the dentist’s hearing over a long period of time. However, dealing with dental drill noise is a different proposition from the applications mentioned above as the frequency range of the peak amplitudes goes from approximately 1.5 kHz to 12 kHz, whereas conventional ANC applications consider a maximum of 1.5 kHz. This paper will review the application of ANC at low frequencies and justify an approach for dealing with dental noise using digital technologies at higher frequencies. The limits of current ANC technologies will be highlighted and the means of improving performance for this dental application will be explored. In particular, technicalities of implementing filtering algorithms on a Digital Signal Processor will be addressed

Real-time adaptive filtering of dental drill noise using a digital signal processor

The application of noise reduction methods requires the integration of acoustics engineering and digital signal processing, which is well served by a mechatronic approach as described in this paper. The Normalised Least Mean Square (NLMS) algorithm is implemented on the Texas Instruments TMS320C6713 DSK Digital Signal Processor (DSP) as an adaptive digital filter for dental drill noise. Blocks within the Matlab/Simulink Signal Processing Blockset and the Embedded Target for TI C6000 DSP family are used. A working model of the algorithm is then transferred to the Code Composer Studio (CCS), where the desired code can be linked and transferred to the target DSP. The experimental rig comprises a noise reference microphone, a microphone for the desired signal, the DSK and loudspeakers. Different load situations of the dental drill are considered as the noise characteristics change when the drill load changes. The result is that annoying drill noise peaks, which occur in a frequency range from 1.5 kHz to 10 kHz, are filtered out adaptively by the DSP. Additionally a schematic design for its implementation in a dentist’s surgery will also be presented

The impact of health system governance and policy processes on health services in Iraqi Kurdistan

BACKGROUND: Relative to the amount of global attention and media coverage since the first and second Gulf Wars, very little has been published in the health services research literature regarding the state of health services in Iraq, and particularly on the semi-autonomous region of Kurdistan. Building on findings from a field visit, this paper describes the state of health services in Kurdistan, analyzes their underlying governance structures and policy processes, and their overall impact on the quality, accessibility and cost of the health system, while stressing the importance of reinvesting in public health and community-based primary care. DISCUSSION: Very little validated, research-based data exists relating to the state of population health and health services in Kurdistan. What little evidence exists, points to a region experiencing an epidemiological polarization, with different segments of the population experiencing rapidly-diverging rates of morbidity and mortality related to different etiological patterns of communicable, non-communicable, acute and chronic illness and disease. Simply put, the rural poor suffer from malnutrition and cholera, while the urban middle and upper classes deal with issues of obesity and Type 2 diabetes. The inequity is exacerbated by a poorly governed, fragmented, unregulated, specialized and heavily privatized system, that not only leads to poor quality of care and catastrophic health expenditures, but also threatens the economic and political stability of the region. There is an urgent need to revisit and clearly define the core values and goals of a future health system, and to develop an inclusive governance and policy framework for change, towards a more equitable and effective primary care-based health system, with attention to broader social determinants of health and salutogenesis. SUMMARY: This paper not only frames the situation in Kurdistan in terms of a human rights or special political issue of a minority population, but provides important generalizable lessons for other constituencies, highlighting the need for political action before effective public health policies can be implemented - as embodied by Rudolf Virchow, the father of European public health and pathology, in his famous quote "politics is nothing but medicine at a larger scale"

Comparative evaluation of methods for estimating retinal ganglion cell loss in retinal sections and wholemounts

To investigate the reliability of different methods of quantifying retinal ganglion cells (RGCs) in rat retinal sections and wholemounts from eyes with either intact optic nerves or those axotomised after optic nerve crush (ONC). Adult rats received a unilateral ONC and after 21 days the numbers of Brn3a+ , bIII-tubulin+ and Islet-1+ RGCs were quantified in either retinal radial sections or wholemounts in which FluoroGold (FG) was injected 48 h before harvesting. Phenotypic antibody markers were used to distinguish RGCs from astrocytes, macrophages/microglia and amacrine cells. In wholemounted retinae, counts of FG+ and Brn3a+ RGCs were of similar magnitude in eyes with intact optic nerves and were similarly reduced after ONC. Larger differences in RGC number were detected between intact and ONC groups when images were taken closer to the optic nerve head. In radial sections, Brn3a did not stain astrocytes, macrophages/microglia or amacrine cells, whereas βIII-tubulin and Islet-1 did localize to amacrine cells as well as RGCs. The numbers of βIII-tubulin+ RGCs was greater than Brn3a+ RGCs, both in retinae from eyes with intact optic nerves and eyes 21 days after ONC. Islet-1 staining also overestimated the number of RGCs compared to Brn3a, but only after ONC. Estimates of RGC loss were similar in Brn3astained radial retinal sections compared to both Brn3a-stained wholemounts and retinal wholemounts in which RGCs were backfilled with FG, with sections having the added advantage of reducing experimental animal usage