175 research outputs found
Neighborhood Deprivation and Eye Diseases.
This is the accepted manuscript. The final version is available from http://www.tandfonline.com/doi/abs/10.3109/09286586.2015.1066017?journalCode=iope20
Forest Sign Maker
Executive Summary:
The Inyo National Forest is arguably one of the most beautiful locations in California, containing natural masterpieces such as Mount Whitney and the Ancient Bristlecone Pine Forest. Despite its magnificence, the Inyo National Forest can be a treacherous region. The Friends of the Inyo take pride in being able to facilitate the viewing experience for all outdoorsmen by maintaining the mountain trails, which includes providing adequate trail signage.
Unfortunately, there is a fundamental issue with the recent state of trail signage in the Inyo National Forest: the rate at which signs are being vandalized or naturally destroyed is greater than the rate at which signs can be produced. More specifically, the problem is that the current sign production process is completely manual; the process of routing the necessary letters and symbols consumes the majority of the production time, since it takes approximately two days to complete. Without adequate signage on the mountain trails, hikers and explorers are at a heightened risk for injury.
We, the Cal Poly Forest Friends, have been commissioned by the Friends of the Inyo to resolve the issue of manufacturing trail signs. We plan on designing, building, and testing a prototype CNC machine for Paul McFarland, an employee of the Friends of the Inyo whom is responsible for replacing signs. This CNC machine can automatically produce a trail sign from a wooden blank so as to expedite the sign replacement process. By comparing different industry methods of etching letters into a wood substrate, researching all applicable signage guidelines for compliance, and optimizing the prototype design for the intended use cases, we have developed a low cost, high capacity CNC router that can be installed directly in Paul McFarland’s workshop.
There has been much work done in the field of CNC machinery, so we believe it is feasible to design a functioning prototype that has been optimized for this purpose. The positional accuracy range of the machine will be broadened from the industry standard of ±0.0005 in to our requirement of ±0.063 inches. This optimized accuracy will allow for emphasis on increased workpiece capacity at a lower total cost. Additionally, by building the prototype CNC router as part of the Cal Poly Multidisciplinary Senior Project class, we will be able to adhere to the revised $3,500 budget. With a successful prototype in hand by June 2015, the sign production rate for the Friends of the Inyo will potentially increase tenfold, and provide the Friends of the Inyo with the ability to replace illegible trail signs within the Inyo National Forest
Precipitation of PEG/Carboxyl-modified gold nanoparticles with magnesium pyrophosphate : a new platform for real-time monitoring of loop-mediated isothermal amplification
2016-2017 > Academic research: refereed > Publication in refereed journal201804_a bcmaVersion of RecordRGCOthersRGC: 501413Others: PGMS Project IDs: P0009500 and P0009150Publishe
Population need for primary eye care in Rwanda: A national survey.
BACKGROUND: Universal access to Primary Eye Care (PEC) is a key global initiative to reduce and prevent avoidable causes of visual impairment (VI). PEC can address minor eye conditions, simple forms of uncorrected refractive error (URE) and create a referral pathway for specialist eye care, thus offering a potential solution to a lack of eye health specialists in low-income countries. However, there is little information on the population need for PEC, including prevalence of URE in all ages in Sub-Saharan Africa. METHODS: A national survey was conducted of people aged 7 and over in Rwanda in September-December 2016. Participants were selected through two-stage probability proportional to size sampling and compact segment sampling. VI (visual acuity<6/12) was assessed using Portable Eye Examination Kit (PEEK); URE was detected using a pinhole and presbyopia using local near vision test. We also used validated questionnaires to collect socio-demographic and minor eye symptoms information. Prevalence estimates for VI, URE and need for PEC (URE, presbyopia with good distance vision, need for referrals and minor eye conditions) were age and sex standardized to the Rwandan population. Associations between age, sex, socio-economic status and the key outcomes were examined using logistic regression. RESULTS: 4618 participants were examined and interviewed out of 5361 enumerated (86% response rate). The adjusted population prevalence of VI was 3.7% (95%CI = 3.0-4.5%), URE was 2.2% (95%CI = 1.7-2.8%) and overall need for PEC was 34.0% (95%CI = 31.8-36.4%). Women and older people were more likely to need PEC and require a referral. CONCLUSIONS: Nearly a third of the population in Rwanda has the potential to benefit from PEC, with greater need identified in older people and women. Universal access to PEC can address unmet eye health needs and public health planning needs to ensure equitable access to older people and women
Montreal Cognitive Assessment for the diagnosis of Alzheimer's disease and other dementias.
BACKGROUND: Dementia is a progressive syndrome of global cognitive impairment with significant health and social care costs. Global prevalence is projected to increase, particularly in resource-limited settings. Recent policy changes in Western countries to increase detection mandates a careful examination of the diagnostic accuracy of neuropsychological tests for dementia. OBJECTIVES: To determine the diagnostic accuracy of the Montreal Cognitive Assessment (MoCA) at various thresholds for dementia and its subtypes. SEARCH METHODS: We searched MEDLINE, EMBASE, BIOSIS Previews, Science Citation Index, PsycINFO and LILACS databases to August 2012. In addition, we searched specialised sources containing diagnostic studies and reviews, including MEDION (Meta-analyses van Diagnostisch Onderzoek), DARE (Database of Abstracts of Reviews of Effects), HTA (Health Technology Assessment Database), ARIF (Aggressive Research Intelligence Facility) and C-EBLM (International Federation of Clinical Chemistry and Laboratory Medicine Committee for Evidence-based Laboratory Medicine) databases. We also searched ALOIS (Cochrane Dementia and Cognitive Improvement Group specialized register of diagnostic and intervention studies). We identified further relevant studies from the PubMed 'related articles' feature and by tracking key studies in Science Citation Index and Scopus. We also searched for relevant grey literature from the Web of Science Core Collection, including Science Citation Index and Conference Proceedings Citation Index (Thomson Reuters Web of Science), PhD theses and contacted researchers with potential relevant data. SELECTION CRITERIA: Cross-sectional designs where all participants were recruited from the same sample were sought; case-control studies were excluded due to high chance of bias. We searched for studies from memory clinics, hospital clinics, primary care and community populations. We excluded studies of early onset dementia, dementia from a secondary cause, or studies where participants were selected on the basis of a specific disease type such as Parkinson's disease or specific settings such as nursing homes. DATA COLLECTION AND ANALYSIS: We extracted dementia study prevalence and dichotomised test positive/test negative results with thresholds used to diagnose dementia. This allowed calculation of sensitivity and specificity if not already reported in the study. Study authors were contacted where there was insufficient information to complete the 2x2 tables. We performed quality assessment according to the QUADAS-2 criteria.Methodological variation in selected studies precluded quantitative meta-analysis, therefore results from individual studies were presented with a narrative synthesis. MAIN RESULTS: Seven studies were selected: three in memory clinics, two in hospital clinics, none in primary care and two in population-derived samples. There were 9422 participants in total, but most of studies recruited only small samples, with only one having more than 350 participants. The prevalence of dementia was 22% to 54% in the clinic-based studies, and 5% to 10% in population samples. In the four studies that used the recommended threshold score of 26 or over indicating normal cognition, the MoCA had high sensitivity of 0.94 or more but low specificity of 0.60 or less. AUTHORS' CONCLUSIONS: The overall quality and quantity of information is insufficient to make recommendations on the clinical utility of MoCA for detecting dementia in different settings. Further studies that do not recruit participants based on diagnoses already present (case-control design) but apply diagnostic tests and reference standards prospectively are required. Methodological clarity could be improved in subsequent DTA studies of MoCA by reporting findings using recommended guidelines (e.g. STARDdem). Thresholds lower than 26 are likely to be more useful for optimal diagnostic accuracy of MoCA in dementia, but this requires confirmation in further studies.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/14651858.CD010775.pub
Process of adaptation, development and assessment of acceptability of a health educational intervention to improve referral uptake by people with diabetes in Sri Lanka.
BACKGROUND: One major barrier to uptake of diabetic retinopathy (DR) services is lack of knowledge and awareness of DR among the people with diabetes (PwDM). Targeted health education (HE) can be a key element in improving the uptake of eye care services. Such interventions are lacking in Sri Lanka. METHODS: A local context specific HE intervention (HEI) was developed by adopting available resources and incorporating views from PwDM and key stakeholders. Four sessions of participatory workshops with PwDM (20 Sinhala and 13 Tamil speaking) and two stage 12 stakeholder interviews were conducted to both develop and pre-test the material. The products were a video and a leaflet, delivered at a medical clinic to a sample of 45 PwDM identified as having DR. Semi-structured interviews were conducted after 4 weeks, to evaluate the acceptability and comprehension of the HEI. Additionally, nine interviews were conducted with clinical providers to explore process issues related to delivery of the HEI. Data analysis was conducted using thematic analysis. RESULTS: The lack of knowledge and awareness on DR, and of the importance of regular DR screening and follow up, combined with poor information on referral pathways were key elements identified from the workshops with PwDM. The stakeholders prioritised the importance of using simple language, and the need for emphasis on improving understanding about the asymptomatic phase of DR. The overall acceptability of the HEI material was satisfactory, although there was some difficulty with interpretation of medical images. Overall, although PwDM liked the ideas of the video, the leaflet was seen as a more practical option, given the busy clinic environment. The key issue was both formats required interaction with the provider, in order to support understanding of the messages. CONCLUSIONS: The process of adapting HE material is not simply translation into the appropriate language. Instead, a tailored approach in a country, context and particular health services setting is needed. This study illustrates the value of using a participatory approach and involving PwDM and stakeholders in the adaptation and pilot testing of a HEI to improve uptake of screening for DR in the context of Sri Lanka
Platinum nanoparticles on reduced graphene oxide as peroxidase mimetics for the colorimetric detection of specific DNA sequence
2015-2016 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Clinical and molecular epidemiology of human bocavirus in respiratory and fecal samples from children in Hong Kong
Background. Human bocavirus (HBoV) is a recently discovered parvovirus associated with respiratory tract infections in children. We conducted the first systematic prospective clinical and molecular study using nasopharyngeal aspirates (NPAs) and fecal samples. Methods. NPAs negative for influenza virus, parainfluenza virus, respiratory syncytial virus, adenovirus, and coronavirus and fecal samples from patients with acute gastroenteritis were included. On the basis of results from a pilot study using 400 NPAs from all age groups, a prospective 12-month study was conducted to detect HBoV in 1200 NPAs and 1435 fecal samples from patients <18 years old by polymerase chain reaction. The complete genome sequences of HBoVs from 12 NPAs and 12 fecal samples were determined. Results. Of the 400 NPAs collected in the pilot study, 20 (5.0%) were found to contain HBoV, all from children <5 years old. In the subsequent prospective study of pediatric patients, HBoV was detected in 83 (6.9%) of 1200 NPAs. Upper and lower respiratory tract infections were equally common. HBoV was detected in 30 (2.1%) of 1435 fecal samples. Fever and watery diarrhea were the most common symptoms. The seasonality of HBoV in NPAs and fecal samples was similar. Codetection with other pathogens occurred in 33% and 56% of NPAs and fecal samples, respectively, from patients with HBoV infection. Genomes of HBoVs from NPAs and fecal samples displayed minimal sequence variations. Conclusions. HBoV was detected in fecal specimens in children with acute gastroenteritis. A single lineage of HBoV was associated with both respiratory tract and enteric infections. © 2007 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio
The Royal College of Ophthalmologists' National Ophthalmology Database study of cataract surgery: Report 7, immediate sequential bilateral cataract surgery in the UK: Current practice and patient selection.
BACKGROUND: Cataract extraction is the most frequently performed surgical intervention in the world and demand is rising due to an ageing demography. One option to address this challenge is to offer selected patients immediate sequential bilateral cataract surgery (ISBCS). This study aims to investigate patient and operative characteristics for ISBCS and delayed bilateral cataract surgery (DSCS) in the UK. METHODS: Data were analysed from the Royal College of Ophthalmologists' National Ophthalmology Database Audit (NOD) of cataract surgery. Eligible patients were those undergoing bilateral cataract extraction from centres with a record of at least one ISBCS operation between 01/04/2010 and 31/08/2018. Variable frequency comparison was undertaken with chi-square tests. RESULTS: During the study period, 1073 patients had ISBCS and 248,341 DSCS from 73 centres. A higher proportion of ISBCS patients were unable to lie flat (11.3% vs. 1.8%; p < 0.001), unable to cooperate (9.7% vs. 2.7%; p < 0.001); underwent general anaesthesia (58.7% vs. 6.6% (p < 0.001)); had brunescent/white/mature cataracts (odds ratio (OR) 5.118); no fundal view/vitreous opacities (OR 8.381); had worse pre-operative acuity 0.60 LogMAR ISBCS vs. 0.50 (first) and 0.40 (second eye) DSCS and were younger (mean ages, 71.5 vs. 75.6 years; p < 0.001). Posterior capsular rupture (PCR) rates adjusted for case complexity were comparable (0.98% ISBCS and 0.78% DSCS). CONCLUSIONS: ISBCS was performed on younger patients, with difficulty cooperating and lying flat, worse pre-operative vision, higher rates of known PCR risk factors and more frequent use of general anaesthesia than DSCS in centres recorded on NOD
Validation of handheld fundus camera with mydriasis for retinal imaging of diabetic retinopathy screening in China: a prospective comparison study.
OBJECTIVES: To investigate the clinical validity of using a handheld fundus camera to detect diabetic retinopathy (DR) in China. DESIGN AND SETTINGS: Prospective comparison study of the handheld fundus camera with a standard validated instrument in detection of DR in hospital and a community screening clinic in Guangdong Province, China. PARTICIPANTS: Participants aged 18 years and over with diabetes who were able to provide informed consent and agreed to attend the dilated eye examination with handheld tests and a standard desktop camera. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was the proportion of those with referable DR (R2 and above) identified by the handheld fundus camera (the index test) compared with the standard camera. Secondary outcome was the comparison of proportion of gradable images obtained from each test. RESULTS: In this study, we examined 304 people (608 eyes) with each of the two cameras under mydriasis. The handheld camera detected 119 eyes (19.5%) with some level of DR, 81 (13.3%) of them were referable, while the standard camera detected 132 eyes (21.7%) with some level of DR and 83 (13.7%) were referable. It seems that the standard camera found more eyes with referable DR, although McNemar's test detected no significant difference between the two cameras.Of the 608 eyes with images obtained by desktop camera, 598 (98.4%) images were of sufficient quality for grading, 12 (1.9%) images were not gradable. By the handheld camera, 590 (97.0%) were gradable and 20 (3.2%) images were not gradable.The two cameras reached high agreement on diagnosis of retinopathy and maculopathy at all the levels of retinopathy. CONCLUSION: Although it could not take the place of standard desktop camera on clinic fundus examination, the handheld fundus camera showed promising role on preliminary DR screening at primary level in China. To ensure quality images, mydriasis is required
- …