Individual's recollections of their experiences in eye clinics and understanding of their eye condition:results from a survey of visually impaired people in Britain

Background/aims: Network 1000 is a UK-based panel survey of a representative sample of adults with registered visual impairment, with the aim of gathering information about people’s opinions and circumstances. Method: Participants were interviewed (Survey 1, n = 1007: 2005; Survey 2, n = 922: 2006/07) on a range of topics including the nature of their eye condition, details of other health issues, use of low vision aids (LVAs) and their experiences in eye clinics. Results: Eleven percent of individuals did not know the name of their eye condition. Seventy percent of participants reported having long-term health problems or disabilities in addition to visual impairment and 43% reported having hearing difficulties. Seventy one percent reported using LVAs for reading tasks. Participants who had become registered as visually impaired in the previous 8 years (n = 395) were asked questions about non-medical information received in the eye clinic around that time. Reported information received included advice about ‘registration’ (48%), low vision aids (45%) and social care routes (43%); 17% reported receiving no information. While 70% of people were satisfied with the information received, this was lower for those of working age (56%) compared with retirement age (72%). Those who recalled receiving additional non-medical information and advice at the time of registration also recalled their experiences more positively. Conclusions: Whilst caution should be applied to the accuracy of recall of past events, the data provide a valuable insight into the types of information and support that visually impaired people feel they would benefit from in the eye clinic.

Corrosion inhibitors for the rehabilitation of reinforced concrete

Four corrosion inhibitors namely sodium nitrite, sodium monofluorophosphate, ethanolamine and an alkanolamine-based mixture were studied by immersing mild steel bars for 42 days in model electrolytes of varied pH and chloride concentration which were intended to simulate the pore solution phase present within carbonated and/or chloride-contaminated concrete. Site trials were carried out on sodium monofluorophosphate and the alkanolamine-based inhibitor to study their depth of penetration into concrete. The influence of various carbonating atmospheres on the pore solution chemistry and microstructure of hydrated cement paste was investigated. Physical realkalisation of carbonated cement paste and a calcium nitrite-based corrosion rehabilitation system for chloride-contaminated cement paste were investigated by monitoring ionic transport within the pore solution phase of laboratory specimens. The main findings were as follows: 1,Sodium nitrite, sodium monofluorophosphate, ethanolamine and the alkanolamine-based mixture all behaved as passivating anodic inhibitors of steel corrosion in air-saturated aqueous solutions of varied pH and chloride concentration. 2,Sodium monofluorophosphate failed to penetrate significantly into partially carbonated site concrete when applied as recommended by the supplier. Phosphate and fluoride penetrated 5mm into partially carbonated site concrete treated with sodium monofluorophosphate. 3,The ethanolamine component of the alkanolamine-based inhibitor was found to have penetrated significant depths into partially carbonated site concrete. 4,Carbonating hydrated cement paste over saturated solutions of sodium nitrite resulted in significant concentrations of nitrite in the pore solution of the carbonated paste. Saturated solutions of sodium chloride, ammonium nitrate, magnesium nitrate and sodium dichromate were investigated and identified as alternatives for controlling the relative humidity of the carbonating environment. 5,Hardened carbonated cement paste can by physically realkalised to a limited extent due to the diffusion of hydroxyl ions under saturated conditions. A substantial proportion of the hydroxyl ions that diffused into the carbonated cement paste however, became bound into the cement matrix. Hydroxyl ion concentrations remained below 5mmol/l within the pore solution of the realkalised cement paste. 6, Nitrite ions penetrated significant distances by diffusion within the pore solution of saturated uncarbonated hydrated cement paste.

Auditory training and adult rehabilitation:a critical review of the evidence

Auditory Training (AT) describes a regimen of varied listening exercises designed to improve an individual’s ability to perceive speech. The theory of AT is based on brain plasticity (the capacity of neurones in the central auditory system to alter their structure and function) in response to auditory stimulation. The practice of repeatedly listening to the speech sounds included in AT exercises is believed to drive the development of more efficient neuronal pathways, thereby improving auditory processing and speech discrimination. This critical review aims to assess whether auditory training can improve speech discrimination in adults with mild-moderate SNHL. The majority of patients attending Audiology services are adults with presbyacusis and it is therefore important to evaluate evidence of any treatment effect of AT in aural rehabilitation. Ideally this review would seek to appraise evidence of neurophysiological effects of AT so as to verify whether it does induce change in the CAS. However, due to the absence of such studies on this particular patient group, the outcome measure of speech discrimination, as a behavioural indicator of treatment effect is used instead. A review of available research was used to inform an argument for or against using AT in rehabilitative clinical practice. Six studies were identified and although the preliminary evidence indicates an improvement gained from a range of AT paradigms, the treatment effect size was modest and there remains a lack of large-sample RCTs. Future investigation into the efficacy of AT needs to employ neurophysiological studies using auditory evoked potentials in hearing-impaired adults in order to explore effects of AT on the CAS.

'There's a hell of a noise':living with a hearing loss in residential care

Background: hearing loss is common in older age. Research with older people in residential care settings has identified high prevalence of hearing loss and low uptake of hearing aids. Hearing loss in these settings is associated with reduced social engagement. Although hearing aids remain the default treatment for presbyacusic hearing loss, these are not well used. We do not know what other modifiable factors contribute to communication problems for older people with hearing loss living in residential care. Objectives: to explore the factors affecting communicating with a hearing loss in residential care. Methods: an ethnographic study in two residential care homes comprised 19 sessions of observation, and in-depth interviews with 18 residents. Observations explored communication behaviour in everyday interactions, including mealtimes, structured groups and informal group activities. Interviews were informed by the observations and identified reasons for these behaviours and communication preferences. Observational data were recorded in field notes and interviews were audio-recorded and transcribed. Analysis was conducted using constant comparison methods. Results: hearing loss affected whether residents were able to access social opportunities. Two key themes influenced this (i) contextual issues compounded communication difficulties and (ii) environmental noise restricted the residents' communication choices. Problems were observed at every mealtime and during formal and informal group activities. The use of hearing aids and access to hearing services did not improve social engagement. Conclusions: environmental and social factors are key to maximising communication opportunities. Improvements to communication in residential care settings could be based on changes in these with input from residents and staff. Further work is needed to develop effective communication strategies in residential care.

Help-seeking for medically unexplained hearing difficulties:a qualitative study

Aims - Up to 10% of audiology patients report diffi culties hearing speech in noise even though clinical investigation reveals normal hearing thresholds, in other words, no evidence of physical pathology. The diagnostic category applied to these patients is known as King-Kopetzky Syndrome (KKS). This study aimed to gather descriptions of patients' experiences of the clinical encounter involving their KKS diagnosis and analyse the themes of help-seeking, as part of a larger study into the process of coping with medically unexplained hearing diffi culties. Method - A qualitative approach was employed, comprising unstructured interviews in the homes of 25 patients who had attended audiology services (and received a diagnosis of KKS) in Bath and Cardiff. Thematic analysis of transcripts was undertaken, infl uenced by grounded theory techniques. Findings - Informants characterized the clinical encounter as either negative or positive. Negative consultations were those in which patients' illness claims were dismissed and as such not validated. Positive encounters were typifi ed by the provision of meaningful information that reconciled clinical information with the patients' experiences of hearing loss. Conclusion - Successful management of medically unexplained illnesses requires the adoption of a patient-centred approach, rather than focusing on the absence of observable pathology

An exploration of the perspectives of help-seekers prescribed hearing aids

Aim - This pilot study uses qualitative methods to learn about the psycho-social needs of people who seek help with hearing loss. Background - There has been some emphasis in health policy to reduce the number of appointments required between assessment of hearing loss and fitting of hearing aids. This may respond to audiological needs but may not address the psycho-social needs. This study piloted a phenomenological approach to identify the patient's perspective. Methods - A phenomenological approach was taken to provide description of patient perspectives. Findings - Six patients reported that help-seeking was primarily influenced by the need to appease social partners and to improve hearing performance. Hearing aids were not regarded as acceptable treatments. Conclusions - Service providers need to consider the psycho-social consequences of hearing-aid issue alongside audiological needs.

A qualitative investigation of decision making during help-seeking for adult hearing loss

Objective: The Any Qualified Provider framework in the National Health Service has changed the way adult audiology services are offered in England. Under the new rules, patients are being offered a choice in geographical location and audiology provider. This study aimed to explore how choices in treatment are presented and to identify what information patients need when they are seeking help with hearing loss. Design: This study adopted qualitative methods of ethnographic observations and focus group interviews to identify information needed prior to, and during, help-seeking. Observational data and focus group data were analysed using the constant comparison method of grounded theory. Study sample: Participants were recruited from a community Health and Social Care Trust in the west of England. This service incorporates both an Audiology and a Hearing Therapy service. Twenty seven participants were involved in focus groups or interviews. Results: Participants receive little information beyond the detail of hearing aids. Participants report little information that was not directly related to uptake of hearing aids. Conclusions: Participant preferences were not explored and limited information resulted in decisions that were clinician-led. The gaps in information reflect previous data on clinician communication and highlight the need for consistent information on a range of interventions to manage hearing loss.

Association of SNPs in LCP1 and CTIF with hearing in 11 year old children:findings from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort and the G-EAR consortium

BACKGROUND: The genetic basis of hearing loss in humans is relatively poorly understood. In recent years, experimental approaches including laboratory studies of early onset hearing loss in inbred mouse strains, or proteomic analyses of hair cells or hair bundles, have suggested new candidate molecules involved in hearing function. However, the relevance of these genes/gene products to hearing function in humans remains unknown. We investigated whether single nucleotide polymorphisms (SNPs) in the human orthologues of genes of interest arising from the above-mentioned studies correlate with hearing function in children. METHODS: 577 SNPs from 13 genes were each analysed by linear regression against averaged high (3, 4 and 8 kHz) or low frequency (0.5, 1 and 2 kHz) audiometry data from 4970 children in the Avon Longitudinal Study of Parents and Children (ALSPAC) birth-cohort at age eleven years. Genes found to contain SNPs with low p-values were then investigated in 3417 adults in the G-EAR study of hearing. RESULTS: Genotypic data were available in ALSPAC for a total of 577 SNPs from 13 genes of interest. Two SNPs approached sample-wide significance (pre-specified at p = 0.00014): rs12959910 in CBP80/20-dependent translation initiation factor (CTIF) for averaged high frequency hearing (p = 0.00079, β = 0.61 dB per minor allele); and rs10492452 in L-plastin (LCP1) for averaged low frequency hearing (p = 0.00056, β = 0.45 dB). For low frequencies, rs9567638 in LCP1 also enhanced hearing in females (p = 0.0011, β = -1.76 dB; males p = 0.23, β = 0.61 dB, likelihood-ratio test p = 0.006). SNPs in LCP1 and CTIF were then examined against low and high frequency hearing data for adults in G-EAR. Although the ALSPAC results were not replicated, a SNP in LCP1, rs17601960, is in strong LD with rs9967638, and was associated with enhanced low frequency hearing in adult females in G-EAR (p = 0.00084). CONCLUSIONS: There was evidence to suggest that multiple SNPs in CTIF may contribute a small detrimental effect to hearing, and that a sex-specific locus in LCP1 is protective of hearing. No individual SNPs reached sample-wide significance in both ALSPAC and G-EAR. This is the first report of a possible association between LCP1 and hearing function.

Diverse functional motifs within the three intracellular loops of the CGRP1 receptor

The CGRP1 receptor exists as a heterodimeric complex between a single-pass transmembrane accessory protein (RAMP1) and a family B G-protein-coupled receptor (GPCR) called the calcitonin receptor-like receptor (CLR). This study investigated the structural motifs found in the intracellular loops (ICLs) of this receptor. Molecular modeling was used to predict active and inactive conformations of each ICL. Conserved residues were altered to alanine by site-directed mutagenesis. cAMP accumulation, cell-surface expression, agonist affinity, and CGRP-stimulated receptor internalization were characterized. Within ICL1, L147 and particularly R151 were important for coupling to Gs. R151 may interact directly with the G-protein, accessing it following conformational changes involving ICL2 and ICL3. At the proximal end of ICL3, I290 and L294, probably lying on the same face of an α helix, formed a G-protein coupling motif. The largest effects on coupling were observed with I290A; additionally, it reduced CGRP affinity and impaired internalization. 1290 may interact with TM6 to stabilize the conformation of ICL3, but it could also interact directly with Gs. R314, at the distal end of ICL3, impaired G-protein coupling and to a lesser extent reduced CGRP affinity; it may stabilize the TM6-ICL3 junction by interacting with the polar headgroups of membrane phospholipids. Y215 and L214 in ICL2 are required for cell-surface expression; they form a microdomain with H216 which has the same function. This study reveals similarities between the activation of CLR and other GPCRs in the role of TM6 and ICL3 but shows that other conserved motifs differ in their function. © 2006 American Chemical Society.

Hearing and vision:the age old problem

Opticians and audiologists tend to see the same people. Many factors that are associated with poorer vision, whether hereditary, pre-natal, or post-natal, are also associated with poorer hearing. The most common factor is simply old age. According to the Royal National Institute for Deaf People (RNID), more than half of all people aged over 60 have some degree of hearing loss and are gradually losing their hearing as part of the ageing process – a process known as presbycusis.

The anatomical and functional correlates of category-specificity

The dramatic effects of brain damage can provide some of the most interesting insights into the nature of normal cognitive performance. In recent years a number of neuropsychological studies have reported a particular form of cognitive impairment where patients have problems recognising objects from one category but remain able to recognise those from others. The most frequent ‘category-specific’ pattern is an impairment identifying living things, compared to nonliving things. The reverse pattern of dissociation, i.e., an impairment recognising and naming nonliving things relative to living things, has been reported albeit much less frequently. The objective of the work carried out in this thesis was to investigate the organising principles and anatomical correlates of stored knowledge for categories of living and nonliving things. Three complementary cognitive neuropsychological research techniques were employed to assess how, and where, this knowledge is represented in the brain: (i) studies of normal (neurologically intact) subjects, (ii) case-studies of neurologically impaired patients with selective deficits in object recognition, and (iii) studies of the anatomical correlates of stored knowledge for living and nonliving things on the brain using magnetoencephalography (MEG). The main empirical findings showed that semantic knowledge about living and nonliving things is principally encoded in terms of sensory and functional features, respectively. In two case-study chapters evidence was found supporting the view that category-specific impairments can arise from damage to a pre-semantic system, rather than the assumption often made that the system involved must be semantic. In the MEG study, rather than finding evidence for the involvement of specific brain areas for different object categories, it appeared that, when subjects named and categorised living and nonliving things, a non-differentiated neural system was involved.

Hearing protectors: a dilemma involving acoustics and personal safety

This thesis is concerned with the optimising of hearing protector selection. A computer model was used to estimate the reduction in noise exposure and risk of occupational deafness provided by the wearing of hearing protectors in industrial noise spectra. The model was used to show that low attenuation hearing protectors con provide greater protection than high attenuation protectors if the high attenuation protectors ore not worn for the total duration of noise exposure; or not used by a small proportion of the population. The model was also used to show that high attenuation protectors will not necessarily provide significantly greater reduction in risk than low attenuation protectors if the population has been exposed to the noise for many years prior to the provision of hearing protectors. The effects of earplugs and earmuffs on the localisation of sounds were studied to determine whether high attenuation earmuffs are likely to have greater potential than the lower attenuation earplugs for affecting personal safety. Laboratory studies and experiments at a foundry with normal-hearing office employees and noise-exposed foundrymen who had some experience of wearing hearing protectors showed that although earplugs reduced the ability of the wearer to determine the direction of warning sounds, earmuffs produced more total angular error and more confusions between left and right. !t is concluded from the research findings that the key to the selection of hearing protectors is to be found in the provision of hearing protectors that can be worn for a very high percentage of the exposure time by a high percentage of the exposed population with the minimum effect on the personal safety of the wearers - the attenuation provided by the protection should be adequate but not a maximum value.

The clinical utility of the middle latency and 40Hz auditory evoked potentials in audiological electrodiagnosis

The two elcctrophysiological tests currently favoured in the clinical measurement of hearing threshold arc the brainstorm evoked potential (BAEP) and the slow vertex response (SVR). However, both tests possess disadvantages. The BAEP is the test of choice in younger patients as it is stable at all levels of arousal, but little information has been obtained to date at a range of frequencies. The SVR is frequency specific but is unreliable in certain adult subjects and is unstable during sleep or in young children. These deficiencies have prompted research into a third group of potentials, the middle latency response (MLR) and the 40HZ responses. This research has compared the SVR and 40HZ response in waking adults and reports that the 40HZ test can provide a viable alternative to the SVR provided that a high degree of subject relaxation is ensured. A second study examined the morphology of the MLR and 40HZ during sleep. This work suggested that these potentials arc markedly different during sleep and that methodological factors have been responsible for masking these changes in previous studies. The clinical possibilities of tone pip BAEPs were then examined as these components were proved to be the only stable responses present in sleep. It was found that threshold estimates to 5OOHz, lOOOHz and 4000Hz stimuli could be made to within 15dBSL in most cases. A final study looked more closely at methods of obtaining frequency specific information in sleeping subjects. Threshold estimates were made using established BAEP parameters and this was compared to a 40HZ procedure which recorded a series of BAEPs over a 100msec. time sweep. Results indicated that the 40mHz procedure was superior to existing techniques in estimating threshold to low frequency stimuli. This research has confirmed a role for the MLR and 40Hz response as alternative measures of hearing capability in waking subjects and proposes that the 40Hz technique is useful in measuring frequency specific thresholds although the responses recorded derive primarily from the brainstem.

Simulating the value of collaboration in multi-actor conservation planning

The loss of habitat and biodiversity worldwide has led to considerable resources being spent for conservation purposes on actions such as the acquisition and management of land, the rehabilitation of degraded habitats, and the purchase of easements from private landowners. Prioritising these actions is challenging due to the complexity of the problem and because there can be multiple actors undertaking conservation actions, often with divergent or partially overlapping objectives. We use a modelling framework to explore this issue with a study involving two agents sequentially purchasing land for conservation. We apply our model to simulated data using distributions taken from real data to simulate the cost of patches and the rarity and co-occurence of species. In our model each agent attempted to implement a conservation network that met its target for the minimum cost using the conservation planning software Marxan. We examine three scenarios where the conservation targets of the agents differ. The first scenario (called NGO-NGO) models the situation where two NGOs are both are targeting different sets of threatened species. The second and third scenarios (called NGO-Gov and Gov-NGO, respectively) represent a case where a government agency attempts to implement a complementary conservation network representing all species, while an NGO is focused on achieving additional protection for the most endangered species. For each of these scenarios we examined three types of interactions between agents: i) acting in isolation where the agents are attempting to achieve their targets solely though their own actions ii) sharing information where each agent is aware of the species representation achieved within the other agent’s conservation network and, iii) pooling resources where agents combine their resources and undertake conservation actions as a single entity. The latter two interactions represent different types of collaborations and in each scenario we determine the cost savings from sharing information or pooling resources. In each case we examined the utility of these interactions from the viewpoint of the combined conservation network resulting from both agents' actions, as well as from each agent’s individual perspective. The costs for each agent to achieve their objectives varied depending on the order in which the agents acted, the type of interaction between agents, and the specific goals of each agent. There were significant cost savings from increased collaboration via sharing information in the NGO-NGO scenario were the agent’s representation goals were mutually exclusive (in terms of specie targeted). In the NGO-Gov and Gov-NGO scenarios, collaboration generated much smaller savings. If the two agents collaborate by pooling resources there are multiple ways the total cost could be shared between both agents. For each scenario we investigate the costs and benefits for all possible cost sharing proportions. We find that there are a range of cost sharing proportions where both agents can benefit in the NGO-NGO scenarios while the NGO-Gov and Gov-NGO scenarios again showed little benefit. Although the model presented here has a range of simplifying assumptions, it demonstrates that the value of collaboration can vary significantly in different situations. In most cases, collaborating would have associated costs and these costs need to be weighed against the potential benefits from collaboration. The model demonstrates a method for determining the range of collaboration costs that would result in collaboration providing an efficient use of scarce conservation resources.