Visual function in aging and age-related macular degeneration including subretinal drusenoid deposits

Age-related macular degeneration (AMD) is the leading cause of visual impairment in the developed world among people over 50 years of age. Although AMD is clinically characterised by the presence of drusen, subretinal drusenoid deposits (SDD) have also been recognized as a distinct morphological feature that confers increased risk of developing advanced AMD. To date, there has been a lack of validated biomarkers that can capture early changes in visual function that strongly correlate to the anatomical alterations which also include SDD phenotype. This thesis aimed to explore functional and structural markers to differentiate between healthy eyes (n=11) and intermediate AMD (iAMD) with SDD (n=11) and without SDD (n=17) and non-foveal atrophic AMD (n=11). Firstly, I assessed scotopic thresholds using a novel dark-adapted chromatic (DAC) perimeter, in healthy aging and in varying AMD disease. Individuals with SDD had depressed retinal sensitivity centrally, particularly inferiorly and nasally. Functionally, eyes with SDD were comparable to eyes with non-foveal atrophy, but structurally differed in outer nuclear layer (ONL) and total retinal volumes and thicknesses. Importantly, only rod-mediated tests were able to distinguish iAMD with and without SDD. Another aim of this thesis was to explore the efficacy of 670nm light on aging and AMD. Although an improvement in scotopic thresholds was observed in healthy aged eyes (n=4) compared to younger eyes (n=5), a pilot study conducted in 40 participants over the age 55 years (12 control, 28 with intermediate AMD) refuted any clinical benefit. In conclusion, this thesis supports the need to re-classify the AMD severity scale by incorporating eyes with SDD as a separate group. This phenotype should be sub-analysed in clinical trials evaluating potential prophylactic agents to delay the progression. Scotopic sensitivity offers diagnostic value, but rod intercept time offers both prognostic and diagnostic value as candidate biomarkers

Estradiol alters the gut microbiota response to high-fat diet

Post-menopausal women have an increased risk of developing metabolic disorders, such as obesity and type-two diabetes. Estradiol, a type of estrogen, which is primarily produced by ovaries and declines in postmenopausal women, protects against diet-induced obesity in women and female mice. However, the mechanisms by which estradiol prevents diet-induced obesity are not completely understood. Host diet has been shown to shift the compositional pattern of the gut microbiota­, and both diet and the gut microbiome have been linked to weight gain and obesity. We hypothesized that one mechanism by which estradiol-treated mice resist diet-induced weight gain is through the gut microbiota. For my thesis, I investigated the effects of estradiol on the gut microbiota to a diet change and analyzed the fecal gut microbiota from fourteen adult C57BL6 mice that were ovariectomized and subcutaneously implanted with capsules containing either 17β-estradiol (E2) or oil (vehicle; control; Veh). All mice were fed a standard rodent diet for 10 days and then switched to a high-fat diet (HFD) for 25 days. To identify and compare microbial community composition of samples across treatments, we analyzed the longitudinal 16S rRNA gene data from fecal pellets. I observed that E2 treatment altered the gut microbiota response and structure following the diet change. Specifically, the gut microbiota in E2 mice response to the diet change was attenuated compared to the Veh mice. Moreover, HFD-fed mice were characterized by increased relative abundances of Firmicutes and Proteobacteria, but these HFD-induced shifts were conservative for the E2-treated group. With the diet change and the lack of E2 treatment, fecal endotoxin levels and taxa associated with inflammatory and metabolic diseases increased greatly, such as Helicobacter and Peptostreptococcaceae. Comparatively, the diet change had no effect on endotoxin levels and induced slight increases in abundance of these inflammatory and metabolic disease associated taxa in E2 mice. Microbes characterized as metabolizers of plant-based diets, such as Ruminococcaceae and S24-7, were, however, associated with and in higher abundance in E2 mice than Veh mice during HFD. In summary, HFD disturbs the gut microbiota diversity and composition, but the HFD associated changes are lessened with E2 treatment. The reduced response and alterations in the gut microbiota to dietary change in E2 mice may be a critical component in understanding the complexities by which estradiol protects against obesity

Simulation of Wheelchair Control by Integration of Computers and Electronics Platform in BCI Controlled Systems

Device control using brain signals is a technique which could dramatically change the life of disabled individuals. An attempt has been made to control such devices using brain signals. This work shows the hardware implementation of controlling a wheelchair using brain signals which is developed using electronics open source platforms to simulate real wheelchair control. This system uses Arduino UNO microcontroller board, L293D driver circuit, two DC motors, wheelchair hardware and wires for connections to produce simulation of wheelchair control

Molar Impactions: Etiology, Implications and Treatment Modalities with Presentation of an Unusual Case

Tooth development results from a complicated multistep interaction between the oral epithelium and the underlying mesenchymal tissue. Abnormal tissue interactions during toothdevelopment may potentially result in ectopic tooth development and eruption. We report a case of unerupted second molar and impacted third molar and an attempt is made to review possible causes of noneruption of teeth and their treatment modalities. It is essential to diagnose and treat eruption disturbances as early as possible because treatment at a later stage is usually more complicated due to the tendency of malocclusion to increase with time and decrease the ability of remaining dentition to adjust

Analysis of Data Aggregation Techniques of IOT

The internet of things is the self configuring network in which sensor nodes can join or leave the network when they want. The security, data aggregation are the two major issues of IOT. In the previous years various techniques are designed to improve data aggregation rate of IOT. The clustering is the technique which can increase data aggregation rate and reduce lifetime of the network. In this paper, various techniques are reviewed to improve lifetime of the network and increase data aggregation rate

May-Thurner syndrome : an uncommon and incidental finding in a postpartum female

May-Thurner syndrome or Cockett syndrome is a pathological condition that arises due to extrinsic compression on iliocaval venous territory, leading to venous outflow obstruction. Here, author presents an incidental finding of left common iliac vein extrinsic compression by right common iliac artery with collateral vessels in the pelvis in a postpartum female

Posterior reversible encephalopathy syndrome in dengue: a rare manifestation

Dengue is an important arthropod born disease with its cases spiking every 2-3 years and spectrum of disease ranging from mild febrile illness to severe illness with multiple systemic complications including rare neurological manifestation. We hereby presented a case report of rare presentation of posterior reversible encephalopathy syndrome (PRES) in an eight year old child suffering from dengue

Exploring the potential of sensing nutrient dynamics using soil-based microbial fuel cells

Degree Not ListedDepartment of AgronomyGanga M HettiarachchiA soil-based microbial fuel cell (MFC) is a bio-electric device that uses soil microorganisms to convert an organic substrate into electricity. The energy generation potential of MFCs may be exploited to ‘sense’ the nutrient status of agricultural soils, which would be faster than traditional soil sampling methods and analysis in laboratories. It could provide real-time data on available soil nutrients. Our studies focused on developing a soil-based MFC that tracks changes in nutrient availability and explores relationships between soil nutrient availability, microbial activity, and MFC performance. We hypothesized that 1) a change in the level of nutrients would produce a different microbial response; hence, a different electrical signal and 2) introducing a biofilm coating on the anode would enhance electrogenic microbial activity and its ability to capture changes in nitrogen dynamics and voltage. A total of five different studies with two soils were conducted sequentially to test these hypotheses. Soil-based MFCs were set up with natural, partially sterilized (a treatment in study 1), and sterilized (a treatment in study 2) soil at field capacity with nitrogen fertilizer (studies 1, 3, 4, and 5), organic carbon treatments (study 2), and Geobacter enriched inoculum (study 4) and pre-developed Geobacter anodic coating (study 5). Soil 1 was used for studies 1-3, while soil 2 was used for studies 4 and 5. The voltage generated was measured by a data logger and recorded every 15 minutes. Soil solution was analyzed to estimate NO3-, NO2- and NH4+, dissolved organic carbon, pH, and electrical conductivity. Soil gas samples (CO2) were collected periodically as a proxy for soil microbial activity and soil organic carbon mineralization. The first study found that MFC performance was better in the control treatment than in higher nitrogen treatments. Voltage in higher nitrogen treatments was significantly low owing to possible nitrate reduction reactions using up the electrons, which could be used for voltage production, or the negative effect of N addition on organic matter decomposition. The voltage of the sterilized treatment decreased significantly with increasing dissolved nitrogen levels. The second study showed that different organic carbon treatments did not differ significantly in voltage, most likely due to non-significant changes in dissolved organic carbon caused by the organic carbon treatments. However, the voltage of sterilized treatment was significantly low, suggesting that the voltages produced in the other treatments were a result of various biotic processes. Biofilm on anode with different nitrogen levels performed better than the control soil. Voltage generation (or MFC performance) was higher with higher nitrogen levels than the control in the second soil. Differences in voltage signals with nitrogen levels were observed, but they varied by soil type, nutrient content, and presence of biofilm. Future studies plan to use a hydrogel-based anode coating to protect the anodic biofilm from exogenous soil microorganisms and selective inoculum of microorganisms for the nutrient in question. Although results are encouraging, more work is needed to deconvolute other signals from the voltage signal corresponding to available soil N levels. If we can successfully model these relationships, this research could help improve crop production rates and ensure the Nation’s food security through 2050 demands

Navigating family planning: unveiling rural-urban disparities among women in India: insights from Indian demographic health survey-5

Background: Over the past few years, there has been an increase in the usage of family planning methods. Female sterilization remains the most commonly used method of contraception. However, there are still disparities in the use of family planning methods between urban and rural areas in India, which can be attributed to differences in education levels, cultural factors, and socio-economic factors. The study aimed to evaluate contraceptive prevalence and urban-rural disparities among married women in India. Methods: The study was based on the data collected under the National family health survey 2019-21. The NFHS-5 covered 5,12,408 currently married women (women in the age group 15-49). Descriptive and analytical analyses were used. The chi-square test and Bivariate logistic regression model were used to find the association between background characteristics and contraception use. Results: The study showed that 65.7% of the participants were using contraception, with female contraception being the most common method of contraception. The use of contraception in urban and rural settings was 67.9% and 65% respectively. Conclusions: The use of contraception has increased, with woman’s age, religion, caste, educational level, wealth index, place of residence and other factors such as total children living, total children ever born, exposure to mass media, son preference and ideal number of children being significant determinants