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There is increasing narrowing of the genetic base of exotic species introduced in many parts of the world. This is causing a restricted genetic diversity and consequential loss of biotic and abiotic tolerance of these species. Hence, there is need to establish the genetic stability of such species for future genetic broadening. One such plant is Moringa oleifera Lam. which belongs to the family moringaceae; a monogeneric family of shrubs and trees consisting of 13 species and is native to India. M. oleifera is the most economically useful species in the genus and is widely cultivated and naturalized in tropical and subtropical areas and in over 60 countries worldwide. In Kenya, M. oleifera is widely cultivated in coast and some parts of Eastern Kenya. A provenance trial was set up at South Eastern Kenya University (SEKU), located at Kwa Vonza location, lower Yatta Sub-County, Kitui County. The aim of the provenance trial was i) to determine whether the collected Moringa exhibited different growth and fruiting habits and ii) if so, select the best performing provenances for large-scale propagation of the species in Kenya. The trial involved fifteen provenances selected from a wide geographical region in Eastern and Coastal regions of Kenya. Each provenance consisted of 200 seedlings at a spacing of 2m by 2m and was replicated three times. The experiment was laid in a randomized complete block design (RCBD). Growth data (diameter and height), fruiting and fruit maturation were measured for a period of 12 months. Monthly growth data were used to generate horizontal and vertical growth curves. Duncan Multiple Range Test (DMRT) and test of homogeneity of variances were used to detect existence of statistically significant differences in the fifteen provenances. The results indicated statistically significant differences (p

Overuse injuries account for a substantial part of sport injury incidence among athletes of various sports and levels. Despite the gradual onset of symptoms, athletes often persevere in training and competing. The present exploratory study aimed to identify a psychological risk profile for overuse injury. One hundred and forty-nine athletes competing in various sports responded to a range of questionnaires measuring the following psychological variables: negative life stress, perfectionistic concerns, perfectionistic strivings, athletic identity, and the coach-athlete relationship. Participants subsequently answered the OSTRC Overuse Injury Questionnaire on a weekly basis during a 10-week period. Using a latent profile analysis, athletes were classified into three latent profiles regarding their psychological characteristics. Athletes in the second profile, characterized by a combination of high athletic identity, perfectionistic concerns and negative life stress and poor coach-athlete relationship, were found to be significantly more often affected by overuse injuries (74% of the time) than individuals in the two other profiles (52% and 48% of the time, respectively). In conclusion, psychological factors may contribute to the risk of overuse injuries through complex interactions (i.e. accounting for interdependencies within a specific configuration of variables) rather than through their independent influences.

Background The purpose of the study was to investigate if participation in a three-month electronic tracking outdoor physical activity and a motivational interviewing (MI) intervention led to positive behavioural, psychological, and physiological outcomes. Method Based on a two-group pre-post experimental design, 12 women and 6 men were randomly assign to an experimental (mean age = 51.9 years) and an control group (mean age = 48.9 years) based on the inclusion criteria: (a) having a primarily sedentary job, (b) limited exercise activity in the past year and (c) employed within the Halmstad Municipal Council. Physical activity data were collected continuously by wrist-worn activity sensors, and pre-post data were collected on the GHQ-12, the BREQ-2, body mass, body fat mass and total body muscle. Measures of cardiovascular fitness (time to exhaustion) were also taken pre to post. The experimental group was supported through individual MI coaching sessions and individual resistance-training programs specifically designed for use in an outdoor gym. Magnitude based inferences (MBI) were calculated based on the disposition of the confidence limits for the mean differences to the smallest worthwhile changes. Results MBI analysis of baseline measures showed differences in body fat between the groups. The experimental group had a small and beneficial increase in in physical activity behaviour (steps). Moreover, the control group had a medium decrease in identified regulation, but the experimental group maintained the same level at the post-measure. Conclusion Participation in the outdoor physical activity and MI intervention resulted in a small increase in in physical activity behaviour (steps) as well as a maintained level of identified regulation in the experimental group. The latter result may be related to a possible combined effect of MI and continuous feedback from the activity tracker. Although there are many questions that remain unanswered, the public health implications of using fitness technology to promote behaviour change seem worthwhile to study. Potential implications for future studies are provided.

This chapter presents the results of a study on the influence of streamflow variability on salt fluxes in a semi-arid Tiva River Basin located in Eastern Kenya. Measurements of salinity, total dissolved solids (TDS), conductivity, and river discharges were undertaken in sampling stations located within the main branch of the river as well as in the tributaries, namely Kauwi, Kalundu, Nzeeu, and Mwitasyano Rivers in the Upper Region of the Tiva River Basin. The mean and maximum river discharges for the sub-basins of the river ranged from 11 to 33 m3s-1 and from 118 to 210 m3s-1, respectively. The peak river discharge at the main Tiva branch was 270 m3s-1. The study shows that there is a significant relationship between the variability of streamflow and the variability of salt fluxes in the river as exemplified by variation of salinity, conductivity, and TDS in the river.

Changes in lung architecture during a course of radiotherapy can alter the planned dose distribution to the extent that it becomes clinically unacceptable. This study aims to validate a quantitative method of determining whether a replan is required during the course of conformal radiotherapy. The proposed method uses deformable image registration (DIR) to flexibly map planning CT (pCT) data to the anatomy of online CBCT images. The resulting deformed CT (dCT) images are used as a basis for assessing the effect of anatomical change on dose distributions. The study used retrospective data from a sample of seven replanned lung patients. The settings of an in-house, open-source DIR algorithm were first optimised for CT-to-CBCT registrations of the anatomy of the thorax. Using these optimised parameters, each patient’s pCT was deformed to the CBCT acquired immediately before the replan. Registration accuracy was rigorously validated both geometrically and dosimetrically to confirm that the dCTs could reliably be used to inform replan decisions. A retrospective evaluation of the changes in dose delivered over time was then carried out for a single patient to demonstrate the clinical application of the proposed method. The geometric analysis showed good agreement between deformed structures and those same structures manually outlined on the CBCT images. Results were consistently better than those achieved with rigid-only registration. In the dosimetric analysis, dose distributions derived from the dCTs were found to match closely to the ‘gold standard’ replan CT (rCT) distributions across dose volume histogram and absolute dose difference measures. The retrospective analysis of serial CBCTs of a single patient produced reliable quantitative assessment of the dose delivery. Had the proposed method been available at the time of treatment, it would have enabled a more objective replan decision. DIR is a valuable clinical tool for dose recalculation in adaptive radiotherapy protocols for lung cancer patients.

This study was undertaken in Kitui South in Kitui County in the south eastern parts of Kenya. The main objective of the study was to develop a spatial model that can be used for selection of suitable sites for sand dam in Kitui South. The study also assessed the spatial variation of sand grain sizes and how these determine the suitability of sites for the sand dams. Data analysis was done using three approaches. The first approach involved the use of the Remote Sensing (RS) technique where data was preprocessed and analyzed using Erdas Imagine software and Geographical Information Systems (GIS) for spatial modelling. The distribution of sand particle-sizes was based on sieve analysis on the sand samples collected from seasonal rivers in the study area. The seasonal rivers that were investigated in this study included Mwila, Kakya, Wiitu, Nguni, Ngunyumu, Muvuko, Kanzilu, Masaa, Katiliku, Ngulungu, Nzeeu, Koma and Katitika. Statistical analysis was done to establish the relationships between the various spatial components affecting sand particle distribution. The results from the spatial model which integrated all factors shows that 16% of the studied sites along the seasonal rivers in Kitui South were fairly suitable for construction of sand dams while 79% were classified as suitable and 5% are categorized as very suitable. Several sites in the central and the entire eastern parts of Mutha Ward were found not suitable for sand dam construction due to poor conditions such as the lack of suitable sand particles, lack of bedrock exposure on the riverbeds, flat terrain, very shallow stream banks, and weak soils on the riverbanks. Suitable sites for sand dams were found on the western and central areas of Kitui South where production and high accumulation of coarse sands was observed along the seasonal rivers. The areas near Mutomo hills and the rocky areas in Ikanga wards were found to be characterized by few excellent sites for sand dams. The optimum accumulation of different grades of sand in the seasonal rivers was found on streams with slope of between 1.5 and 6% that were dominated with 0 to 40% coarse sands, 0 to 30% fine gravels, 0 to 20% fine sands, and 20 to 80% medium sands. The accumulation of fine gravels was found to be closely related to the distribution of D30, D60 and D90 sand particle-sizes (0.4-4 mm) while accumulation of coarse sands showed good relationship with the distribution of the medium size sand (0.2-0.4 mm). The accumulation of medium sands was equally high when the occurrence of coarse sands was minimal. Different grades of sand were found to be strongly influenced by the changes in the elevation of the stream especially with regard to the accumulation of the medium sands (r=0.76) and coarse sands(r=0.75). Out of 80 investigated sites, 59% of them were dominated with uniform sands (Cu 5). The study also found that 86% of the sites along the seasonal streams were dominated with medium sands while 10% were dominated with fine sands and the rest (4%) dominated by coarse and gravelly sands. From the results this study concludes that 59% of the 80 sites that were investigated in this study have a high potential for providing suitable sites for sand dams in Kitui South.

This chapter presents the results of a study on the influence of streamflow variability on salinity, total dissolved solids (TDS) and conductivity in a semi-arid Tiva River Basin in Kenya. Measurements of salinity, TDS, conductivity and river discharges were undertaken in sampling stations by applying standard hydrologic methods. The study shows that there is a significant relationship between the variability of streamflow and the variability of salinity, conductivity and TDS in the river. The high salt concentrations were a result of high evapotranspiration and seepage of subterranean water from bank storage and groundwater aquifers. Inter-sub-basin variations in the levels of salinity were attributed to differences in land uses, lengths and sizes of the sub-basins. Sustainable irrigation and land use practices in the semi arid Tiva River Basin requires construction of water reservoirs for control of salinity levels in the river.