Data pre-processing to identify environmental risk factors associated with diabetes

Genetics, diet, obesity, and lack of exercise play a major role in the development of type II diabetes. Additionally, environmental conditions are also linked to type II diabetes. The aim of this research is to identify the environmental conditions associated with diabetes. To achieve this, the research study utilises hospital-admitted patient data in NSW integrated with weather, pollution, and demographic data. The environmental variables (air pollution and weather) change over time and space, necessitating spatiotemporal data analysis to identify associations. Moreover, the environmental variables are measured using sensors, and they often contain large gaps of missing values due to sensor failures. Therefore, enhanced methodologies in data cleaning and imputation are needed to facilitate research using this data. Hence, the objectives of this study are twofold: first, to develop a data cleaning and imputation framework with improved methodologies to clean and pre-process the environmental data, and second, to identify environmental conditions associated with diabetes. This study develops a novel data-cleaning framework that streamlines the practice of data analysis and visualisation, specifically for studying environmental factors such as climate change monitoring and the effects of weather and pollution. The framework is designed to efficiently handle data collected by remote sensors, enabling more accurate and comprehensive analyses of environmental phenomena that would otherwise not be possible. The study initially focuses on the Sydney Region, identifies missing data patterns, and utilises established imputation methods. It assesses the performance of existing techniques and finds that Kalman smoothing on structural time series models outperforms other methods. However, when dealing with larger gaps in missing data, none of the existing methods yield satisfactory results. To address this, the study proposes enhanced methodologies for filling substantial gaps in environmental datasets. The first proposed algorithm employs regularized regression models to fill large gaps in air quality data using a univariate approach. It is then extended to incorporate seasonal patterns and expand its applicability to weather data with similar patterns. Furthermore, the algorithm is enhanced by incorporating other correlated variables to accurately fill substantial gaps in environmental variables. Consistently, the algorithm presented in this thesis outperforms other methods in imputing large gaps. This algorithm is applicable for filling large gaps in air pollution and weather data, facilitating downstream analysis

Effects of Impurities on Calcium Oxalate Crystallization as Measured by Atomic Force Microscopy

Calcium oxalate crystals are found in kidney stones as either calcium oxalate monohydrate (COM) or calcium oxalate dihydrate (COD). COM crystals are the most abundant form as they are thermodynamically more stable than COD crystals under physiological conditions. Certain aspartic acid-rich molecules such as osteopontin (OPN) are known to affect stone formation by inhibiting COM and COD growth. We have studied COM {010} and COD {100} faces in the presence of OPN, poly-aspartic acid (poly-ASP) and synthetic peptides derived from OPN to investigate the inhibitor mechanism. We observed that poly-ASP preferentially inhibits one particular direction of {010} faces on COM crystals, creating “finger-like” features, while growth continues in other directions. We find that these features appear at a threshold concentration of poly-ASP that varies with the length of the polymer. Attempts to model the threshold concentration suggest that this is due to a competition between adsorption of polymer to already-pinned steps and removal of poly-ASP by desorption and possibly coverage by advancing steps between strongly pinned steps. Growth of {100} faces of COD crystals in the presence of synthetic peptides derived from OPN with different iso-electric points displayed varying levels of inhibition. The two principal directions of the elongated elliptical hillocks on {100} faces were inhibited to different degrees by the peptides. This preferential inhibition is most likely the result of different Ca2+ ion densities and structures of the two different step directions. The effects of imaging on the growth itself were studied for the case of COM growth in the presence of OPN. In the presence of OPN molecules, a continuously-scanned area showed faster growth relative to a larger area scanned less frequently. This enhanced vertical growth in the continuously-scanned area was found to vary with the OPN concentration and calcium oxalate supersaturation. We modeled this effect using a modified version of the Cabrera-Vermilyea model (1958), in which steps are pinned by adsorbed impurities, resulting in a decreased propagation speed due to the resulting curvature. In our case, we assume adsorption directly to steps, rather than to terraces as in the Cabrera-Vermilyea model

Part I Total Synthesis Of (+,-)-hirsutene Part Ii Photochemical And Photophysical Properties Of N-benzoylindoles

Part One. The synthesis of polycyclic compounds usually requires various synthetic approaches to construct the required carbon skeletons. This thesis describes a sequence which leads to the preparation of the tricylo (6.3.0.{dollar}0\sp{lcub}2,6{rcub}{dollar}) undecane skeleton found in a number of physiological fungal metabolites. The key steps in this sequence are photochemical cycloaddition of the enol of 5,5-dimethylcyclohexane-1,3-dione to a cyclopentene, followed by intramolecular reductive coupling of the dione with a low valence titanium compound. A formal synthesis of the fungal metabolite hirsutene is described using this procedure. The route involves the photochemical (2+2) cycloaddition of 5,5-dimethylcyclohexane-1,3-dione to 2-methyl-2-cyclopentenol, followed by the treatment of the silylated photoadducts with a low valence titanium reagent resulting in intramolecular reductive coupling to give the hirsutene carbon skeleton with the desired regiochemistry. Desilylation with fluoride ion, followed by sequential catalytic hydrogenation and Jones\u27 oxidation completed the formal synthesis by yielding the norketone, obtained by ozonolysis of hirsutene.;Part Two. This part of the thesis describes the studies performed to determine the nature, and the reactive species in the photoannelation reaction of N-benzoylindole with cyclopentene which was found to proceed via a triplet state. The existence of a solvent polarity dependent charge-transfer triplet excited state, in addition to a solvent polarity independent triplet state, was proposed to rationalize the rate constant values obtained for N-benzoylindole from a combination of dilution, quenching and triplet counting experiments.;The fluorescence properties of various N-carbonyl substituted indoles 142a and 156 - 162 were examined. The N-benzoylindole derivatives 142a and 158 - 160 were shown to fluoresce weakly at anomalously long wavelengths and were dependent on the polarity of the solvent used. It was concluded that the initially formed singlet excited state is non-emissive and can relax to an intramolecular charge-transfer state which is weakly fluorescent. The solvent induced shifts in the wavelength of the fluorescence emission correlate well with Lippert equation. A poor correlation with the empirical {dollar}{lcub}\rm E\sb{lcub}T{rcub}{rcub}(30){dollar} solvent polarity parameter was observed

Systematic process of waste management for sustainable operations of hotel industry

Hotel industry contributes to Gross Domestic Product of Sri Lanka by 12.5% (2018) which is a considerable value. Hotel industry contributes for a considerable amount of daily wastes since there are number of hotel networks which are spread throughout the country. Determining the sustainability adaptation of the Sri Lankan hotel industry is crucial since there is not a strict legal background that specifically governs the hotel industry waste, except for a few regulations related to tourism. Addressing gaps in between such requirements and waste management systems in hotels from the perspective of the Circular Economy concept, this research identifies match making opportunities for hotel industry waste. This ensures that waste is not thrown away and is used in the production process of other goods or providing services. Although many studies on the concept of CE have been carried out globally, it is a novel topic in the Sri Lankan context. Further, research that adapted the CE concept for managing hotel industry waste is scarce. This research therefore investigates on applying the CE concept for managing hotel sector waste by analyzing, the 6R principles associated with the CE concept, the waste match making process and its cost implications. A case study strategy with semi structured interviews as the data collection tool was used in the study. Case studies were preceded by a brief pilot study to set the context for the main study. Manual content analysis method was used for analyzing the collected data. Through the research findings, it was revealed that the possibility of adapting waste exchanging program for hotel industry mainly depends on the category and the location of the hotel. Even though the barriers exist, those can be mitigated through proper vendor selection and waste match making. This research identified possible waste matches, pros and cons of such matches and the enablers, barriers and favorable outcomes of such match making exercises. Keywords: Sustainability, Circular Economy (CE), Waste exchanging, Match making, Hotel industr

In situ conservation of crop wild relatives

Poster presented at 13. Meeting of the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA) held in FAO, Rome (Italy), 18-22 Feb 200

Mind the large gap : novel algorithm using seasonal decomposition and elastic net regression to impute large intervals of missing data in air quality data

Air quality data sets are widely used in numerous analyses. Missing values are ubiquitous in air quality data sets as the data are collected through sensors. Recovery of missing data is a challenging task in the data preprocessing stage. This task becomes more challenging in time series data as time is an implicit variable that cannot be ignored. Even though existing methods to deal with missing data in time series perform well in situations where the percentage of missing values is relatively low and the gap size is small, their performances are reasonably lower when it comes to large gaps. This paper presents a novel algorithm based on seasonal decomposition and elastic net regression to impute large gaps of time series data when there exist correlated variables. This method outperforms several other existing univariate approaches namely Kalman smoothing on ARIMA models, Kalman smoothing on structural time series models, linear interpolation, and mean imputation in imputing large gaps. However, this is applicable only when there exists one or more correlated variables with the time series with large gaps

Evidence based Scientific Narrative Review on the Anticoagulant Mechanisms of Allium sativum (Garlic)

Introduction: Garlic (Allium sativum, Family: Amaryllidaceae) is a seasoning plant cultivated all over the world. Garlic contains a lot of bioactive compounds including organosulfur compounds, saponins, phenolic compounds, and polysaccharides. Anticoagulant activity is one of the pharmacological properties of Garlic. The aim of this study was to review the mechanism of the anticoagulant activity of garlic and summarise the potential evidence about the anticoagulant activity of garlic from past studies. Method: Literature searches were conducted on PubMed and Google Scholar databases. 44 full articles were reviewed in detail in this study. The findings were reviewed and potential evidence for the anticoagulant mechanisms of garlic was summarised. Results: Organosulfur compounds in garlic play a major role in the anticoagulant property of garlic. Garlic exhibits anticoagulant activity mainly through three mechanisms. Those are inhibiting platelet aggregation, retarding thrombin formation, and promoting fibrinolysis. The anticoagulant activity of garlic is proven by several human, animal and in-vitro studies. Garlic significantly inhibits adenosine diphosphate and epinephrine induced platelet aggregation in healthy subjects. Garlic administration inhibit the thrombus formation in rats. Aqueous and methanolic extracts of garlic prolong prothrombin time. Extension in clotting time is reported with increasing concentrations of garlic extract. Conclusions: Garlic has been reported as a medicinal plant showing anticoagulant activity by resisting platelet aggregation, inhibiting thrombin formation and enhancing fibrinolysis and this study suggests that garlic reduces the risk of thrombosis therefore cardiovascular complications.   Keywords: Anticoagulant Activity, Garlic, Thrombosi

Mineral Content of Selected Seaweed Varieties in Southern and North Western Sea of Sri Lanka

Seaweeds are a rich source of health beneficial bioactive nutraceuticals and currently, they are under-utilised in Sri Lanka. Thus, this study is to get an idea about the possibility of utilising seaweed in Sri Lankan food industry. In the present study, elemental composition analysis of Ulva fasciata obtained from 3 locations Mirissa (5°56/40.5// N: 80°27/20.2// E), Point Dondra (5°55/45.7//N: 80°35/02.5// E) and Galle (6°02/01.1// N: 80°12/52.2// E) and red algae varieties Gracilaria edulis and Gracilaria sp. obtained from Kalpitiya (8°15/40.8// N: 79°46/33.9// E and 8°13/35.0// N: 79°43/34.8// E) respectively. The elemental analysis was carried using X-ray fluorescence (XRF) analyzer. The results revealed that the predominant mineral of U. fasciata obtained from the 3 locations and Gracilaria sp. as calcium. While the predominant mineral in G. edulis was potassium. All the 5 varieties have various concentrations of elements such as K, Ca, Mn, Fe, Cu and Zn. Significantly high lead content was observed in U. fasciataobtained from Point Dondra. The elemental compositions showed variations among the same species obtained from different locations. The results also revealed that seaweed is a good source of certain essential and trace minerals.Keywords: Ulva fasciata, Gracilaria edulis, Gracilaria sp., minerals, seaweed