110 research outputs found
Advancing Hyperacuity for Vision Screening
Introduction:
The human visual system is extremely sensitive to certain spatial visual tasks. It can detect the subtle misalignment of closer objects to a degree of 2-5 arcseconds, which is smaller than the foveal cone diameter or spacing. This ability is referred to as hyperacuity, and one such visual task is the Vernier task, which involves misalignment detection of Vernier lines or dots. It is also called Vernier acuity and has a significant diagnostic value for screening various eye abnormalities. However, due to methodological and technical limitations, its utility was restricted to laboratory applications due to concerns over test reliability and testing time. I hypothesized that applying advanced psychophysical procedures, techniques, and modern technological interventions might improve the Vernier acuity testing standards for clinical consideration. Therefore, I attempted to address the challenges noticed in the literature by advancing the methodology and technicality to improve the Vernier acuity test efficiency for clinical application.
Aims:
⸰ Experiment 1 (Chapter-2): To develop a software application and assess the Vernier acuity program performance, measurements, and stimuli characteristics.
⸰ Experiment 2 (Chapter-3): To enhance the Vernier acuity program efficiency, assess program performance and reliability for technical validation.
⸰ Experiment 3 (Chapter-4): To modify the Vernier acuity program for the visual field quantification (Hyperacuity perimetry) and assess reliability for technical validation.
⸰ Experiment 4 (Chapter-5): To develop a software application for the visual distortions quantification (Metamorphopsia) using Vernier acuity-based bisectional program and assess reliability for technical validation.
Methods:
This study was performed through two pilot studies: the first pilot study had five adult volunteers with the best corrected visual acuity of 20/20 vision in the right eye (tested right eye only) and included all the experiments from Chapter 2, whereas the second pilot study was carried out on 21 adult emmetrope (unaided 20/20 vision) volunteers (tested both eyes individually) and included all the experiments from Chapters-3, 4, and 5. I used PsychoPy3 to develop each software program. However, I employed two methods to provide the test results efficiently and reliably for clinical testing. I developed three software applications and could only perform technical validation because of the pandemic.
⸰ Experiment 1 (Chapter-2): I programmed a software program and employed a 3-Down, 1-Up adaptive staircase method and three alternative forced choices technique to quantify the Vernier acuity. The Vernier acuity was measured at seven vertical separations (gaps) to assess test performance. The initial testing was focused on determining test performance using stimuli shapes, followed by technical validation of the software application program and assessment of stimuli contrast for standardization.
⸰ Experiment 2 (Chapter-3): I adjusted the measurement parameters to improve test efficiency. I assessed the program performance from response accuracy, reaction time, and testing time, along with repeatability of measurements for technical validation of the Vernier acuity program.
⸰ Experiment 3 (Chapter-4): I modified the Vernier acuity program to quantify the hyperacuity perimetry in superior, inferior, nasal, and temporal visual fields. I assessed the repeatability of measurements for technical validation of this modified Vernier acuity program.
⸰ Experiment 4 (Chapter-5): I programmed a Vernier bisection program to quantify the metamorphopsia using a method of adjustment. The testing involved Vernier stimuli in two different orientations and referred to them as patterns (A and B), Pattern-A had a presentation of two vertical and horizontal line stimuli that are equally away from the center of the screen in either direction, whereas pattern B involved presentations of pattern-A at oblique angles to the screen center. Using both patterns, I measured the metamorphopsia in central 5 degrees and assessed the repeatability of the measurements and testing time for technical validation of the Vernier bisection program.
Results:
⸰ Experiment 1 (Chapter-2): In the initial experiment, the line stimuli achieved comparable measurements to dot stimuli at most gap sizes except at 32 arcminutes of gap size. The test detected the lowest misalignment of 2 arcseconds at 2 arcminutes of gap size. The mean lowest acuity was below 8 arcseconds at 2 arcminutes, and the highest acuity was within an arcminute at 128 arcminutes. The negative contrast line stimuli were comparably precise to positive line stimuli at most gap sizes except at 16 arcminutes.
⸰ Experiment 2 (Chapter-3): The right eyes were repeatable at most of the gap sizes except for the 32 and 64 gap sizes, whereas the left eyes were repeatable at all gap sizes except 128. The right and left eye measurements were statistically the same at both visits. Since no difference was observed between the eyes, results from both eyes were compiled to assess the test performance and response accuracy. The Vernier acuity measured at 16, 8, 4, and 2 gap sizes were statistically repeatable, and the correlation was positive but weak. The response accuracy was estimated to be above 90% for mean correct responses, below 3% for mean incorrect responses, and about 5% for mean aligned responses through the gap sizes at both visits. The estimated reaction time was just below a second for mean correct responses, below 0.75 seconds for the mean incorrect responses, and about 2.5 seconds for the mean aligned responses. The test time was below 2 minutes at each gap size at both visits.
⸰ Experiment 3 (Chapter-4): The right eye hyperacuity perimetry results were repeatable in all four quadrants of 15 gap size, and the correlation was positive but weak in all quadrants except the superior visual field, where the correlation was negative and weak. Whereas for gap size 30, the results were repeatable in all quadrants except the inferior visual field, where the results were not repeatable. However, results from all the quadrants had a positive but weak correlation. The left eye hyperacuity perimetry results were repeatable in all quadrants of 15 gap size, except the nasal visual field, where the results were not repeatable. However, results from all the quadrants had a positive but weak correlation. For gap size 30, the results were repeatable in all four quadrants, and all quadrants had a positive but weak correlation. The results from both eyes showed no significant difference for a gap of 15 arcminutes. However, there was a substantial difference between the eyes only at the inferior field for a gap of 30 arcminutes.
⸰ Experiment 4 (Chapter-5): The right eye metamorphopsia results were repeatable in the central 5 degrees using a pattern A with a positive but weak correlation at all degrees except 5 and 1 degrees, where the correlation was negative and weak. Similarly, the results were repeatable in the central 5 degrees using a pattern B except for 5 degrees, and the correlation was positive but weak at all degrees except 3 and 2 degrees, where there was a negative and weak correlation. On the other hand, the left eye results were repeatable in the central 5 degrees using a pattern A with positive and moderate to strong correlations at all degrees. Similarly, the results were repeatable in the central 5 degrees using a pattern B except for 4 degrees, and the correlation was positive and moderate to strong at all degrees. There was no difference between the eyes for individual patterns at both visits.
Conclusions:
⸰ Experiment 1 (Chapter-2): The developed software application program measured the Vernier acuity precisely using 3-down, 1-up, an adaptive staircase method, and the 3AFC technique. In addition, I standardized stimuli for shape and contrast to measure the Vernier acuity. The calculated results are precise and consistent with the previously reported data. Therefore, motivating to advance the test further for Vernier acuity testing. While performing the test, some areas for improvement were identified. By adjusting the necessary parameters, the test's efficiency can be enhanced. I plan to make those adjustments in the following pilot testing and perform technical validation.
⸰ Experiment 2 (Chapter-3): I adjusted the necessary parameters to improve the efficiency of the Vernier acuity testing. The results showed that the program is efficient, robust, and repeatable. The mean Vernier acuity measured at seven different gap sizes was consistent with previously reported data and comparable with pilot study 1 results. This cohort’s Vernier acuity measured at smaller gap sizes was highly dependable. The measurements were significantly repeatable at most gap sizes but were poorly dependable. Therefore, this program may need further modifications to achieve better reliable results for clinical testing.
⸰ Experiment 3 (Chapter-4): I modified the Vernier acuity program to quantify the Vernier acuity in eccentric 5 degrees of the macula (para-foveal area). The right eye results were repeatable for 15 arc minutes of gap size, whereas the left eye results were repeatable for the 30 arc minutes of gap size. However, both eyes had poor reliability at most of the gap sizes except the superior field of gap 30, where the reliability was moderate. This inconsistency between the eyes could be due to distinct reasons and therefore needs further investigations to address the underlying cause.
⸰ Experiment 4 (Chapter-5): I programmed a software application to quantify the metamorphopsia using a method of adjustment. The right eye results were repeatable at most gap sizes for both patterns. However, the measurements were poorly dependable at most gap sizes of both patterns. Similarly, the left eye results were repeatable at most gap sizes for both patterns. However, the measurements were poorly dependable at most gap sizes of both patterns, except at 3 degrees of pattern A and 5 and 2 degrees of pattern B, where the reliability was moderate. Further modifications in the program may provide better reliability for clinical testing
Digitized Engineering Notebook
Digitized Engineering Notebook is a website Application which allows users to execute same functionalities as a paper Notebook in real time such as storing data in digital format so that files, videos, photos, animations can be inserted, and users can share the data from any part of the world through cloud technology with less time. With Digitized Engineering Notebook users can create and edit projects, collaborate through discussion board, and also drag notes, notebooks, or tag for fast access. Further, users can keep detailed notes and can work on ongoing projects. The main page of Digitized Engineering Notebook includes tabs like Menu, Site, Supervise operations, Creation of new projects, Different list of projects, Table of contents, and a search function. Some essential functionalities include user login, log entry forms, converting HTML to pdf files, uploading files, log printings, etc. Data is secure and reliable as it can be stored in different places
Drug utilisation evaluation in patients with osteoarthritis in tertiary care hospital
Background: The principle aim of our study is to assess the prescribing pattern of drugs used in treatment of osteoarthritis patients. Methods: A prospective and empirical study was carried out at department of orthopaedics-Shadan teaching and general hospital, for 6 months.Results: During the study period, a total 120 patients were enrolled, of which 57% were females, 43% were males and common age group was ≥60 years. It was found that 56% of OA patient have history of trauma and 62% of obese individual contribute to occurrence of OA. It was found that subjects developed comorbidities like CV disorders which is 36%. It was found that 63% have OA for a duration of >2 years, 56% had no knowledge about their medications, 59% have co-morbidity, 61% have treatment complexity. NSAID’s, calcium, vitamin D3, glucosamine and chondroitin sulphate were the most frequently prescribed drugs in OA accounting for 50%. It was reported that 55% were adherent to OA medication, adherence to physical activity was 64%, adherence to weight loss was 62%.Conclusions: Our study manifest that majority of the patients had duration of >2 years of OA. The reasons for the uncontrolled pain was due to absence of awareness about osteoarthritis-related difficulties, drugs, low calcium diet, increased stress, obesity, and advanced age. Continuous health education, patient counselling, information about medication adherence and satisfaction at follow-ups is essential to avoid the problems
Role of serum Zinc and Copper levels in patients with acne vulgaris
Background: Acne vulgaris is a disorder in which hair follicles develop obstructing horny plugs (comedones) and the reason is unknown. The aim of the present study was to assess the relationship of zinc and copper to Acne vulgaris. Material and Methods: Young female patients in the age group of 13 to 19 years, with the problem of acne attending the out-patient department of Dermatology of a tertiary teaching general hospital over a period of six months, were included in this study. Female attenders (friends) of the patients of the same age, without acne comprised of the control group. Group 1 consisted of 50 patients with acne and group 2 was a control group having 25 normal individulas. The blood samples of patients and controls were collected on the scheduled date and analysed for serum zinc and copper levels at National Institute of Nutrition, Hyderabad by Atomic absorption spectrometry. Results: Mean Serum zinc levels in patients was 24.4  2.4 whereas the levels in controls was 99.4  4.5. The observation is that the mean value in acne patients is statistically significant and lower than controls (p<0.001). Mean serum copper levels in patients and control was 119±14 and 131.2±4.6 respectively. The observation is that mean value in acne patients is statistically significant (p <0.001). Conclusion: Zinc deficiency is one of the main causes of acne and zinc supplementation has got a marked role in its treatment. Whereas hypercupraemia needs further evaluation
A parametric study on compression molding of reference parts with integrated features using carbon composite production waste
Assessing the effects of World Vision Ghana education project interventions on beneficiaries in the Saboba district of Ghana
Enrolment, Performance and Retention are the key elements in providing quality education and building the skills and technical expertise of its human resource. The roll out of quality education is however thwarted by some challenges and therefore there is the need for concerted efforts on the part of Private Sector, Public Sector and Non-Governmental Organizations (NGOs) to collaborate and contribute to achieving this excellence. The study sought to examine the effects of World Vision Intervention education component on the project beneficiaries at the basic school level in the Saboba district of northern Ghana. The investigation sought to give answers to various inquiries like: perception of stakeholders on the effectiveness of the project, effect of the project on academic performance, school enrolment as well as the challenges associated with the implementation of the intervention Program. The approach to the study was eclectic. Results revealed that more than two-thirds of the stakeholders identified Water and Sanitation, and Education as the priority areas of World Vision. It also attributed the appreciation of enrolment to sponsorship packages enjoyed by beneficiaries and the aggressive mount of enrolment campaign drives.  However, increase in enrolment did not translate into performance, as percentage of pupils graduating from the basic school level to higher levels of academic was not impressive. The situation worsened as the performance of the girl child continues to lag compared to their boys counterparts. The study suggests that development actors should incorporate pupil enrolment campaign Programs into their mainstreamed local Programs, with much emphasis on quality instructional delivery as this will enable pupil to climb higher educational ladder. Also, consultation strategy should be incorporated into donors’ agencies Programs to encourage stakeholders to fully participate at each stage (design to implementation) of the Program since that will allow optimal achievement of the intended goals
OPTIMIZATION OF RESOURCE ALLOCATION AND LEVELING USING GENETIC ALGORITHMS
Resource allocation and leveling are of the top challenges in project management, due to the
complexity of projects. This research aims to develop an optimization model for resource
smoothing, so that.
The proposed model is formulated using C++ program for resource smoothing. The project
management software MS-Projects is adopted hereto perform resource leveling to facilitate
achieving the optimal solution.
The proposed model utilizes a system that depends on Genetic Algorithms (GAs) procedure built
in C++ program to find the optimum solution.
This research reach concludes that it is possible to smooth resources using Genetic Algorithms
program and compares then with MS-Project when the GA results are better than MS-Project.
Three case studies have been applied in this research and the application results come identical
with research objectives, to form the conclusion.
Then comes the recommendations regarding adopting and using the research results in
construction planning and project management. Further suggestions related to the research subject
are proposed for future works.
Mathematical Modelling of the Relationship between Two Different Temperament Classifications: During the Covid-19 Pandemic
In medicine, it is well known that healthy individuals have different physical and mental characteristics. Ancient Indian medicine, Ayurveda and the Persian-Arabic traditional Unani medicine has two distinct approaches for the classification of human subjects according to their temperaments. The individual temperament is an important foundation for personalized medicine, which can help in the prevention and treatment of many diseases including COVID-19. This paper attempts to explore the relationship of the utmost important concepts of these systems called individual temperament named as Prakruti in Ayurveda and Mizaj in Unani practice using mathematical modelling. The results of mathematical modelling can be adopted expediently for the development of algorithms that can be applied in medical informatics. For this, a significant literature review has been carried out. Based on the previous researchers' reviews the essential parameters have been identified for making the relationship and hypothesis were framed. The mathematical modelling was adopted to propose the existence of the relationship between the parameters of such an ancient and rich medicine systems. The hypotheses are validated through the mathematic driven model. Doi: 10.28991/esj-2021-01258 Full Text: PD
Laser Assisted Fibre Placement of Thermoplastic Composites:From the theory behind Disney movies to aircraft
Poster presentation at the 26th Engineering Mechanics Symposium, hosted by the Graduate School on Engineering Mechanics. Prize won for best submission in the poster contes
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