No description available.

none

The greater part of land in the area south of Pretoria is underlain by dolomite from the Chuniespoort Group of the Transvaal Supergroup. In South Africa dolomite rock has a notorious reputation for the formation of sinkholes and subsidences. Thousands of people reside and work in the Centurion area, where numerous sinkholes have occurred causing damage and in some instances loss of property. Centurion has rapidly densified over the last 40 years. This study deals with the hazard of sinkhole formation in the Centurion CBD and surrounding area as well as comparing the Method of Scenario of Supposition by Buttrick and van Schalkwyk (1995) based on an ‘abused’ land use situation to this ‘managed’ area in Centurion. Various classification systems have been proposed since the 1970’s in an attempt to evaluate the stability of sites on dolomite in South Africa and a summary of each are provided in the dissertation. The classification system that is currently used in South Africa is the method proposed by Buttrick (1992) which is known as the Method of Scenario Supposition. A total of 119 sinkholes have been recorded in the Centurion CBD area since the early 1970’s. Three lives havebeen lost as a result of a sinkhole in the area and a total of seven houses or units had to be demolished. Draft guidelines for allocation of each hazard class has been developed, which is referred to as the proposed ‘Modified Method of Scenario Supposition’. This is mainly based on the dolomite bedrock depth and the mobilization potential of the overlying horizons. Eight Inherent Hazard Classes are present which classify an area into having a low, medium or high hazard of sinkhole formation. After each borehole was assigned its specific inherent hazard class, the information was recorded in ESRI ArcGIS® software. The Spatial Analyst® extension of ArcMap® was used to create a map showing the areas of low, medium and high hazard of sinkhole formation. The map generally indicates a medium to high susceptibility to sinkhole formation in the Centurion CBD area with pockets of low hazard areas. This hazard map was then used to make recommendations for each of the eight Inherent Hazard Classes on suitable development types as per the draft SANS 1936-1:2012 guidelines. Various methods are used to calculate the hazard of sinkhole formation using data such as the historicaloccurrence of sinkholes, geological information and the hazard map. These results are used to compare this ‘managed land’ to the ‘abused land’ scenario used by Buttrick and van Schalkwyk (1995). Overall, the hazard for sinkhole formation in the Centurion CBD area does not correlate well with the method proposed by Buttrick and van Schalkwyk (1995). According to the anticipated number of events by Buttrick and van Schalkwyk far more sinkholes should have occurred in the high hazard areas. In contrast, the most sinkholes in the Centurion CBD area occurred in the areas classified as having a medium hazard for sinkhole formation. / Dissertation (MSc)--University of Pretoria, 2013. / Geology / unrestricted

Cannabidiol (CBD) has unverified use in the treatment of ADHD but parents are giving CBD to their children to treat hyperactivity and restlessness. CBD has suppressive effects on immune function therapeutically but the effect of pre-exposure to CBD on the response to an immune challenge is unknown. To investigate this, male and female juvenile rats were treated orally with either corn oil or 20 mg/kg or 60 mg/kg CBD daily for 5 days followed 24 hours later by intranasal challenge with a viral mimic, Resiquimod (R848). After 6 hours, lungs were collected for the analysis of gene expression of select cytokines. Pretreatment with CBD did not alter the R848-induced expression of IL-4, TNF-α, IL-1α, IL-18, or TGF-1β. However, pretreatment with CBD suppressed the R848-induced expression of IL-1β, IL-8, MIP-2, IL-10, and IL-6. Our data suggest that prior exposure of juveniles to CBD alters the innate immune response in the lungs.

Yes / Methyl Decanoate (MeDC) is a Fatty Acid Methyl Ester (FAME) and is an important chemical compound with global production of 31 million tons per year. However, synthesis of methyl decanoate (MeDC) via esterification of Decanoic Acid (DeC) with methanol by reactive distillation is operationally challenging due to difficulty of keeping the reactants together in the reaction zone as methanol being the lightest component in the mixture can separate itself easily form the other reactant deteriorating significantly the conversion of DeC using either conventional batch or continuous distillation column. This is probably the main reason for not applying the conventional route for MeDC synthesis. Whether Semi-batch Distillation column (SBD) and the recently developed Integrated Conventional Batch Distillation column (i-CBD) offer the possibility of revisiting such chemical reactions for the synthesis of MeDC is the focus of this paper. The minimum energy consumption (Qtot) as the performance measure is used to evaluate the performances of each of these reactive column configurations for different range of methyl decanoate purity and the amount of product. It is observed that the use of i-CBD column provides much better performance than SBD column in terms of the production time and the maximum energy savings when excess methanol is used in the feed. However, the SBD column is found to perform better than the i-CBD column when both reactants in the feed are in equal amount. Also, the optimization results for a given separation task show that the performance of two-reflux intervals strategy is superior to the single-reflux interval in terms of operating batch time, and energy usage rate in the SBD process at equimolar ratio.

During recent years the possible medical application of cannabis has been discussed more and more. It turns out, that the active substances (cannabinoids cannabidiol and tetrahydrocannabinol) have a significant potential in medicine and do not have to be only misused as a recreational drug. The Department of Crop Production (Faculty of Agrobiology, Food and Natural Resources) is the first institution with granted permission to legally cultivate cannabis, with higher THC content than 0,3 %, for research purposes. The first part of literate review recapitulates the basic knowledge about the cannabis, its biologically active substances and current legislation. The second part describes the endocannabinoid system and utilization of cannabis in the field of medicine. This thesis aims to evaluate the THC and CBD content in seven different cannabis cultivar strains (Nurse Jackie, Conspiracy Kush, Jillybean, Jack Cleaner 2, Jack Skellington, Nordle and National Health Service). The cannabis plants were cultivated in three cultivation cycles. The content of active substances in dried and homogenised inflorescence was analysed by gas chromatography with flame ionization detection (GC-FID) according to UN methodology. Based on the analysis, the appropriate genotypes were chosen, which are in accordance of Regulation 236/2015 Sb. and needs of the patients. According to results it was found, that all seven analysed cultivars are suitable for medical utilization regarding the content of THC and CBD. The highest average content of THC was measured by cultivar Jack Cleaner 2. On the other hand, the lowest THC content was established by cultivar Nordle. It was demonstrated, that the differences in THC content are connected rather to genotype variation than cultivation factors. The main goal of the thesis was to discover which of the seven cultivars will be stable regarding not only THC and CBD content, but also the crop yield. In those regards the research shows the cultivar Jack Cleaner 2 and Nurse Jackie as the most suitable. Preliminary results indicate that these two cultivar strains would be the most suitable for the therapeutic purposes.

Yes / Medical cannabis is one of the most commonly reported therapeutic treatments sought for chronic pain. The wide acceptance and research in alternative medicine has put medical cannabis in the limelight, where researchers are widely examining the therapeutic benefits of medical cannabis and its association to treat chronic pain. Objective: The purpose of this scoping review is to provide an overview of the perspectives on CBD as an alternative treatment for chronic pain among health professionals and legal cannabis users.

The buffer layer in Cu(In,Ga)Se2 solar cells can improve cell performance. In this work we make CdS buffer layer by chemical bath deposition (CBD) without ammonia. CBD without ammonia were sought out since ammonia is a volatile compound. Different recipes for making CdS were tested; only one of the tested recipes actually produced something that is worth further investigating. This recipe used sodium citrate, an innocuous compound instead of ammonia. The best performance was 0.15 % off from the reference.This is almost as good as the used baseline process. However the worst almost completely killed the solar cells. Cell performance dropped by more than absolute 10 %. This demonstrates that chemical bath deposition can have profound effects on the solar cell performance. When trying to improve the best cells only detrimental effects showed up. This might show that, a part in the recipe used, NaOH has detrimental effects on solar cells. Ammonia free chemical bath deposition is possible, however so far it has not produced as good results as the reference. The difference is however very small, which makes it worth further investigating with moreand better solar cell material.

1.1 Background: Despite Cannabis being the most widely used recreational drug in the western world (Earlywine, 2002) little is known about its potential association with anxiety and panic pathology. 1.2 Literature Review: A systematic literature review was conducted with twenty-nine studies critically reviewed. Papers suggested contradictory and equivocal results across all research designs and anxiety disorders. Whilst a significant number of studies have observed an association between cannabis and anxiety/anxiety disorders, the nature and direction of that association is still a point of contention. 1.3 Research Report: No known British empirical research has focused on exploring relationships between cannabis and panic attacks. Also no known research has investigated the differential effects of consuming different types of cannabis on panic pathology. Inspired somewhat on established research (e.g. Zolvensky et al., 2006a) a cross-sectional study was undertaken to explore the potential relationship between cannabis and anxiety. A self-selecting opportunity sample of 306 students drawn from both of Leicester’s universities completed a battery of questionnaires concerning cannabis use, tobacco use, panic attack history, alcohol use, poly-substance use and various psychometrics. Significant levels of both cannabis use and panic attack history were reported among the sample. Survival analysis revealed cannabis users were of significant increased risk (OR 2.01) of experiencing a panic attack compared to non-users. Mann-Whitney analysis found cannabis users who use mainly high potency ‘sensimillia’ experienced significantly more lifetime panic attacks than those who used other types. Limitations are explored. 1.4 Implications: The research report concludes that cannabis use is a risk factor in experiencing panic attacks and experiencing more lifetime attacks. High potency cannabis further increases this risk. Education for substance misuse and mental health professionals is recommended along with cannabis use forming part of assessment for panic attacks/disorder. 1.5 Critical Appraisal: Reflective appraisal of the research process is presented alongside key learning points.

Presented diploma thesis is focused on production of secondary metabolites under influence of external factors.in cannabis (Cannabis sativa L.). Theoretival part contains phylogenetical, morphological and botanical characterization of the given species. The part is further expanded by description of major cannabis constituents and their biosynthetic pathways. In the end of the chapter, methods for elicitation are described. Main goal of the experimental part was to compare influence of vaious fertilizers and product containing coloid silver on morphological characteristics and selected secondary metabolites content. Highest yield was observed within plants fertilized by Powder Feeding. Highest THC content was observed in plants fertilized by Jungle in da Box. Variation of height, yield and secondary metabolites within experimental population was observed, however was not statistically conclusive. Influence of Altron Silver was not statistically proven.