Diabetic eye disease in the west of Scotland

This thesis reports the results of an investigation into some aspects of diabetic eye disease. The first three chapters give an account of the present state of knowledge of diabetes mellitus and diabetic retinopathy. In chapter 4 the multifactorial aetiology of diabetic retinopathy is discussed. In relation to this a study of the possible role of blood and plasma viscosity in the pathogenesis of diabetic retinopathy is reported. It was found that in diabetes blood and plasma viscosities are increased. Diabetics with proliferative retinopathy were found to have higher blood viscosity, at both high and low shear rates, than diabetics with background or no retinopathy. Diabetics with serious forms of retinopathy had higher fibrinogen levels than controls. Chapter 5 reports results of a study carried out in general practice to determine the prevalence of diagnosed diabetes in the West of Scotland. In Chapter 6 results of an investigation into the most practical means for the screening and detection of diabetic retinopathy are reported. This work was carried out in collaboration with ophthalmologists, opticians, physicians, and technicians from the Tennent Institute of Ophthalmology and Glasgow Royal Infirmary. Ophthalmoscopy was found to be a reliable tool for the purpose of screening for diabetic retinopathy. Ophthalmologists and trained and interested physicians were equally efficient in this respect. Other investigations such as fluorescein angiography, tests of colour vision, contrast sensitivity to grating patterns, and measurement of visual fields were time consuming, costly and needed highly specialised instruments which might not necessarily be available in centres concerned with early detection of serious diabetic retinopathy. Diabetic subjects had lower contrast sensitivity to grating patterns, compared to normal subjects, as measured by the Arden grating test. Contrast sensitivity was inversly proportional to the degree and severity of retinopathy. The severity of diabetic retinopathy also affected colour discrimination. The most seriously affected were those with exudative retinopathy. The study also confirmed that measurements of visual acuity are not a good indication of the severity of retinopathy. On the basis of results of the above study funduscopic examination of 400 consecutive diabetics attending a large hospital diabetic clinic, Glasgow Royal Infirmary, was performed (Chapter 7). This work was carried out to determine the prevalence of diabetic retinopathy in this population of diabetic individuals. A similar study was carried out on diabetics attending general practice (chapter 8). Identified diabetics were asked to attend for a full physical, including an eye examination. 35 per cent of patients were found to have ophthalmoscopically recognisable diabetic retinopathy. The onset of blindness was earlier in diabetic males than females. Diabetics were found to be registered as visually handicapped at an earlier age than the non-diabetic blind individuals (Chapter 9). In Chapter 10 an account is given of the indications, techniques, and advantages of photocoagulation in the treatment of diabetic retinopathy. Visual results of major studies carried out in this respect are summarised. A study of the short-term effects of laser therapy and exposure to high intensity light from ophthalmic instruments was carried out on patients attending the Tennent Institute (Chapter 11). Normal volunteers and diabetic patients were exposed to the tungsten light of a slit-lamp microscope. Also diabetics who received laser treatment for proliferative diabetic retinopathy were studied. Visual acuity on Snellen's Chart, colour vision as determined by the Farnsworth-Munse1l 100-Hue test, and contrast sensitivity measured by Arden grating test were all determined before, 20 minutes, and 24 hours after exposure. These visual functions were not found to be significantly affected by laser therapy or exposure to ophthalmic instruments during photocoagulation or a slit-lamp examination although the majority of normal and diabetic patients showed a temporary drop in visual acuity 20 minutes after light exposure, in all cases returning to within 1 line of Snellen's Chart. In the final chapter (12) various conclusions from the proceeding chapters are discussed and some recommendations are made with regard to the desirability and design of screening programmes for the early detection of diabetic retinopathy

Duty-cycle division multiplexing (DCDM): a novel and economical optical multiplexing and electrical demultiplexing technique for high speed fiber optics networks

A new multiplexing and demultiplexing technique based on duty cycle division is proposed, thus the name duty cycle division multiplexing (DCDM). DCDM can be applied in both electrical and optical domains. The new technique allows for more efficient use of time slots as well as the spectrum, taking advantage of both the conventional TDM and FDM. In this paper, three channels operating at the same speed of 10 Gbps are multiplexed in the optical domain and demultiplexed in the electrical domain. The performance comparison is made against 30 Gbps TDM, and the experimental simulation results show that the minimum sensitivity achieved is -26 dBm and -25.5 dBm for the two systems respectively, thus a 0.5 dB improvement

Parents’ Acceptance to Alveolar and Nasoalveolar Molding Appliances during Early Cleft Lip and Palate Care: A Call for High-Quality Research

AIM: Acceptance and compliance of the parents are an essential pillar in the success of pre-surgical infant orthopedic (PSIO) treatment. The aim of this systematic review is to evaluate the burden of care associated with the alveolar molding (AM) and nasoalveolar molding (NAM) appliances as experienced by the parents with unilateral complete cleft lip and palate (UCLP) infants. METHODS: An electronic search was carried on by two reviewers in eight search engines, as well as a manual search till July 2019. Randomized controlled trials (RCTs) comparing AM/NAM appliances to controls in infants with UCLP were selected. Risk of bias was evaluated using Cochrane risk of bias assessment tool for RCTs. RESULTS: One RCT was included in the qualitative analysis. Non-significant differences were found in the amount of mothers’ satisfaction between the intervention and control groups. CONCLUSIONS: Insufficient low-quality evidence is available regarding the effects of AM and NAM on parents’ satisfaction and burden of care. No conclusions can be withdrawn from the existing studies. High-quality research is needed to elucidate the degree of parents’ acceptance to the molding appliances. PROSPERO registration number: CRD42016043174

Experimental and Theoretical Study of Vacuum Cooling System

A vacuum cooling system and the parameters which affect on its performance were studied experimentally and theoretically. For the experimental study the rig was built up to studying the performance of cooling system in three cases. These cases are: Cooling water by vacuum only, cooling water in conventional method, and cooling water by vacuum with condensation. The experimental results show that the addition of a condenser to the vacuum cooling system leads to sweep of largest amount of generated vapor, also the time consumed for the process was decreased. The times required for cooling 45 g from water from temperature 29oC to 10oC for the three test cases were 4375 second, 3535 second and 263 second, respectively. Vacuum cooling with condenser is a fast cooling of three systems test, which is about (13.7 times) faster than the system of natural convection cooling. To work properly, the existence of condenser is very important in vacuum cooling. It normally removes the large amount of water vapor generation (about 94%). For the theoretical study, a computer program was built up by employing the governing equation to simulate the performance of the vacuum cooling system. The theoretical results indicate an acceptable agreement with the experimental results. Also, the results show that the decreasing of condenser temperature causes decreasing of cooling time according to the equation (t = 0.2031Tcd4 - 2.8958 Tcd3 + 16.406 Tcd2 - 21.104 Tcd + 313.39), and increasing the evaporation surface area leads to decreasing of cooling time according to the equation (t=1/ (0.0006*Area+0.0005)), and the increasing of water mass causes in increasing of cooling time according to the equation (t=7.2667*mass+14)

Rates of referable eye disease in the Scottish National Diabetic Retinopathy Screening Programme

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.Peer reviewedPublisher PD

A Novel Poisoned Water Detection Method Using Smartphone Embedded Wi-Fi Technology and Machine Learning Algorithms

Water is a necessary fluid to the human body and automatic checking of its quality and cleanness is an ongoing area of research. One such approach is to present the liquid to various types of signals and make the amount of signal attenuation an indication of the liquid category. In this article, we have utilized the Wi-Fi signal to distinguish clean water from poisoned water via training different machine learning algorithms. The Wi-Fi access points (WAPs) signal is acquired via equivalent smartphone-embedded Wi-Fi chipsets, and then Channel-State-Information CSI measures are extracted and converted into feature vectors to be used as input for machine learning classification algorithms. The measured amplitude and phase of the CSI data are selected as input features into four classifiers k-NN, SVM, LSTM, and Ensemble. The experimental results show that the model is adequate to differentiate poison water from clean water with a classification accuracy of 89% when LSTM is applied, while 92% classification accuracy is achieved when the AdaBoost-Ensemble classifier is applied

Measurement of a wide-range of X-ray doses using specialty doped silica fibres

Using six types of tailor-made doped optical fibres, we carry out thermoluminescent (TL) studies of X-rays, investigating the TL yield for doses from 20 mGy through to 50 Gy. Dosimetric parameters were investigated for nominal 8 wt% Ge doped fibres that in two cases were co-doped, using B in one case and Br in the other. A comparative measurement of surface analysis has also been made for non-annealed and annealed capillary fibres, use being made of X-ray Photoelectron Spectroscopy (XPS) analysis. Comparison was made with the conventional TL phosphor LiF in the form of the proprietary product TLD-100, including dose response and glow curves investigated for X-rays generated at 60 kVp over a dose range from 2 cGy to 50 Gy. The energy response of the fibres was also performed for X-rays generated at peak accelerating potentials of 80 kVp, 140 kVp, 250 kVp and 6 MV photons for an absorbed dose of 2 Gy. Present results show the samples to be suitable for use as TL dosimeters, with good linearity of response and a simple glow curve (simple trap) distribution. It has been established that the TL performance of an irradiated fibre is not only influenced by radiation parameters such as energy, dose-rate and total dose but also the type of fibre

Characterization of amorphous thermoluminescence dosimeters for patient dose measurement in X-ray diagnostic procedures

We investigate the use of novel Ge-doped amorphous silica flat fibers as thermoluminescence dosimeters (TLDs) in verifying patient entrance surface-dose (ESD) in diagnostic examinations. Selected fibers with established dosimetric characteristics (including energy dependence, linearity, reproducibility, and fading) were loaded into plastic capsules in groups of six. The fibers have been calibrated against a parallel plate ionization chamber, use being made of x-rays generated at 70 kVp, accessing a Secondary Standards Dosimetry Laboratory (SSDL) facility. The fiber characterization measurements were made using a Toshiba X-ray machine operating within the nominal energies range 40 kVp to 150 kVp, for doses in the range 0.02 mGy up to 3 mGy. For doses from 2 mGy up to 150 mGy, the flat fibers exhibit linearity between TL yield and dose, reproducible to better than 3% standard deviation following repeat measurements (n¼3). A marked energy-dependent response is observed for photons generated at potentials from 40 kVp to 150 kVp. From present results, it is concluded that Ge-doped fibers represent a viable system for use in diagnostic dosimetry, corrections being made for the various factors influencing TL yield

Hyperspectral discrimination of tree species with different classifications using single- and multiple-endmember.

Discrimination of tree species with different ages is performed in three classifications using hyperspectral data. The first classification is between Broadleaves and pines; the second classification is between Broadleaves, Corsican Pines, and Scots Pines, and the third classification is between six tree species including different ages of Corsican and Scots Pines. These three classifications are performed by having single- and multiple-endmember and considering five different spectral measure techniques (SMTs) in combination with reflectance spectra (ReflS), first and second derivative spectra. The result shows that using single-endmember, derivative spectra are not useful for a more challenging classification. This is further emphasized in multiple-endmember classification, where all SMTs perform better in ReflS rather than derivative in all classifications. Furthermore, using derivative spectra, discrimination accuracy become more dependent on the type of SMTs, especially in single-endmember. By employing multiple-endmember, the within-species variation is significantly reduced, thereby, the remaining challenge in discriminating tree species with different ages is only due to the between-species similarity. Overall, discrimination accuracies around 92.4, 76.8, and 71.5% are obtained using original reflectance and multiple-endmember for the first, second, and third classification, which is around 14.3, 17, and 8.3% higher than what were obtained in single-endmember classifications, respectively. Also, amongst the five SMTs, Euclidean distance (in both single- and multiple-endmember) and Jeffreys–Matusita distance (in single-endmember and derivative spectra) provided the highest discrimination accuracies in different classifications. Furthermore, when discrimination become more challenging from the first to second and third classification, the performance difference between different SMTs is increased from 1.4 to 3.8 and 7.3%, respectively. The study shows high potential of multiple-endmember to be employed in remote sensing applications in the future for improving tree species discrimination accuracy