Surgical Management of Gastroesophageal Reflux in Children: Risk Stratification and Prediction of Outcomes

Introduction: Since the 1980s fundoplication, an operation developed for adults with hiatus hernia and reflux symptoms, has been performed in children with gastroesophageal reflux disease (GORD). When compared to adult outcomes, paediatric fundoplication has resulted in higher failure and revision rates. In the first chapter we explore differences in paradigm, patient population and outcomes. Firstly, symptoms are poorly defined and are measured by instruments of varying quality. Secondly, neurological impairment (NI), prematurity and congenital anomalies (oesophageal atresia, congenital diaphragmatic hernia) are prevalent in children. / Purpose: To develop methods for stratifying paediatric fundoplication risk and predicting outcomes based on symptom profile, demographic factors, congenital and medical history. / Methods: Study objectives are addressed in three opera: a symptom questionnaire development (TARDIS:REFLUX), a randomised controlled trial (RCT) and a retrospective database study (RDS). TARDIS: REFLUX: In the second chapter, digital research methods are used to design and validate a symptom questionnaire for paediatric GORD. The questionnaire is a market-viable smartphone app hosted on a commercial platform and trialed in a clinical pilot study. / RCT: In the third chapter, the REMOS trial is reported. The trial addresses the subset of children with NI and feeding difficulties. Participants are randomized to gastrostomy with or without fundoplication. Notably, pre- and post-operative reflux is quantified using pH-impedance. / RDS: In the fourth chapter, data mining and machine learning strategies are applied to a retrospective paediatric GORD database. Predictive modelling techniques applied include logistic regression, decision trees, random forests and market basket analysis. / Results and conclusion: This work makes two key contributions. Firstly, an effective methodology for development of digital research tools is presented here. Secondly, a synthesis is made of literature, the randomised controlled trial and retrospective database modelling. The resulting product is an evidence-based algorithm for the surgical management of children with GORD

Digital Rights Management: Improving Online Digital Images Copy Rights Management through an Enhanced Least Significant Bit Steganographic Algorithm

Digital media no doubt presents numerous advantages compared to the traditional analog media. Of the most importance is the fact that digital content (images, graphics, audio and video) can be easily copied, transmitted, retrieved and distributed over private and open access networks. The global availability of the internet- certainly the most impactful information exchange tool today- plus the numerous file sharing tools freely available have made the distribution of copyrighted digital media files simple and straightforward. Duplication of exact copies of original images, for example can be easily done and circulated without authentication. As much as this is an advantage in trying to enhance sharing of information, it certainly creates problems of ownership and authenticity and digital rights protection. There already exists copyright laws that provide for protection of all online content but the task of continuously guarding the web and correctly identifying those that infringe against these laws is increasingly becoming enormous. There is therefore need to continuously invest in development of new technologies and algorithms that will make it more and more difficult to illegally copy or use someone else content. To improve security of copyrighted online digital images, this paper proposes the use of an enhanced LSB steganographic algorithm that employs a selective and randomized approach in picking specific number of target image bits to swap with the owners signature authentication bits using a pseudo random number generator (PRNG). The carefully selected password seed is used to determine the set of selected numbers used for targeting specific image bits for the signature hiding. An experimental design is setup to determine the effectiveness of the method by comparing and analyzing the stego images’ statistical characteristics and the ability of steganalysis methods to detect the hidden signature. The experimental results indicate improved levels of imperceptibility and hence improved security against illegal copying. Keywords: Digital Media, Steganography, Copyright, Steganalysis, Stego image, imperceptibilit

A comparative study on the nutritional status of children (6-59 months) in a world vision project area and a non-project area in Kathonzweni division, Makueni District, Kenya

A cross-sectional survey was conducted in Kathonzweni division, Makueni district to assess and compare the nutritional status of children (6-59 months) drawn from households participating in a World Vision project vis-à-vis non-project area. The purpose of the study was to provide region specific data on the nutrition situation in the World Vision Project area and establish whether there is any significant  difference from the non-operational area. A total of 320 households, of which 160 were from the World Vision project area each with at least a child aged between 6-59 months were randomly selected. In households with more than one child at this age category, only one child was selected. Structured questionnaires were administered to mothers or to alternative caretakers while anthropometric  measurements were taken for all the children in the study households. Statistical package for Social Scientists (SPSS/PC+) computer package was used for data entry and analysis. Indices of nutritional status that is weight-for-age, height-for-age and weight-for-height were computed using the Epi-Info programme. The prevalence of stunting in the project area (46.5%) was slightly higher than among the non-project area (42.1%). A significant relationship was found between the children's age and their nutritional status based on the prevalence of wasting and ofunderweight (p<0.01) while nutritional status, based on stunting, was significantlyassociated with birth order. Overall, there was no significant difference in  prevalence of stunting, wasting and underweight between the world vision project area and nonproject area. However, the prevalence of stunting and underweight was higher than the national levels. It is, therefore, concluded that chronic malnutrition is a problem in the study area and age is an important determining factor. Even though World Vision Kenya has been involved in development projects in the area, there is still need for more targeted nutrition interventions by the organization.Key Words: Under-fives, Nutritional status, Wasting, Stunting, UnderweightUne étude transversale a été menée dans la Division de Kathonzweni, District de  Makueni, au Kenya, en vue d’évaluer et comparer l’état alimentaire d'enfants (qui ont entre 6 et 59 mois) pris de ménages participant à un projet de World Vision par rapport à une région en dehors de ce projet. Le but de l'étude était de fournir des données spécifiques à des régions sur la situation de la nutrition dans la région couverte par le projet de World Vision et établir s'il y a une différence significative par rapport à la zone non couverte par ce projet. Un total de 320 ménages, dont 160 étaient de la région couverte par le projet de World Vision, ayant chacun au moins un enfant âgé de 6-59 mois, ont été sélectionnés au hasard. Dans des ménages ayant plus d’un enfant se trouvant dans cette catégorie d'âge, un enfant seulement a été retenu pendant la sélection. Des questionnaires structurés ontété administrés aux mères ou à d’autres responsables d’enfants tandis que des mesures anthropométriques ont été prises pour tous les enfants dans les ménages faisant l’objet de l’étude. Le logiciel informatique Statistical package for Social Scientists (SPSS/PC+) a été utilisé pour le stockage et l'analyse des données. Les indices de l’état alimentaire qui est mesuré par le poids par rapport à l’âge, la  taille/hauteur par rapport à l’âge et le poids par rapport à la taille/hauteur étaient calculés en utilisant le programme Epi-Info. La fréquence du retard de croissance dans la région couverte par le projet (46.5%) était légèrement plus élevée que dans la région non couverte par le projet (42.1%). Un rapport significatif a été trouvé entre l'âge des enfants et leur état alimentaire en se basant sur la fréquence de la perte de poids et de la maigreur (p<0.01) tandis que l’état alimentaire, basé sur le retard de croissance, était considérablement associé avec l'ordre de naissance.Dans l‘ensemble, il n’y avait aucune différence significative dans la fréquence de retard de croissance, la perte de poids et la maigreur entre la région couverte par le projet de World Vision et la région non couverte par le projet. Cependant, la  fréquence du retard de croissance et de la maigreur était plus élevée que les niveaux nationaux. Il est donc conclu que la malnutrition chronique est un problème dans la région étudiée et que l’âge est un facteur déterminant important. Bien que World Vision Kenya ait été impliqué dans des projets de développement dans cette région, il faut que cette organisation oriente ses interventions davantage sur la nutrition.Mots-clés: Les enfants de moins de cinq ans, l’état de l’alimentation, la perte de poids, le retard de croissance, la maigreur.

An Econometric analysis of the relationship between oil price change and inflation dynamics in Kenya

The purpose of this study was to analyse the relat ionship between global oil price and inflation in Kenya. The specifi c objective of the study was to investigate the . impact of fluctuations of global oil price on Kenyan inflation. This study employed the use of monthly data for all the variables for the period 2005 to 2015, which was split into two: Pre-Energy Regulatory Commission (ERC) and Post-ERC. The study conducted Stationarity tests before using a Vector Autoregressive (VAR) model to estimate the data. The analysis showed that during the first sample period of 2005 to ,2010 (Pre-ERq, changes to the Brent price had no impact on inflation in Kenya. However, during the second sample period of 2011 to 2015 (Post-ERC), the Brent price was seen to impact inflation positively. This meant that any changes to the global price would result in an increase in local inflation, owing to the fact that the ERC derives local oil prices from the intemational oil prices . To mitigate this effect , the paper recommended that the ERC should take up more effective price controls

Assessment of relationship between management policies and transfer of skills: A case of public secondary school heads in Nyeri County, Kenya

Despite heavy investments in training and development, low-quality education standards and challenges in management practices have been a sticky problem in the Kenyan education sector. Organization Theory guided the main aim of this study in establishing the relationship between management policies and transfer of skills for public secondary school headteachers in schools management. The study adopted a descriptive research design. Questionnaires were used to collect quantitative and qualitative data. Data were analyzed through descriptive and inferential statistics. The study population comprised 226 headteachers.  A mixture of stratified random sampling and census study was adopted in sampling 69 respondents. The results established that management policies explained a 23.4% variation in the transfer of skills for school heads. ?1 = 0.536 and p-value = 0.000 (p<0.05) indicated that management policies had positive and significant effects on transfer of skills. The study established that unsupportive policies like the Students Council, two centers of power, strict policies, and lack of inclusivity in policy formulation adversely affected school heads in implementing learned skills. The study recommends fair representation of all categories of education stakeholders in policies review and formulation to alleviate challenges associated with management policies to enhance the transfer of skills. The Government should address the issue of two centers of power in the public basic education sector. The paper sought to call the attention of the professional development trainers to exercise follow-ups to assess post-training behavioral outcomes in the context of organizational climate

INFLUENCE OF TEACHER TRAINING ON USE OF MUSIC AS A MEDIUM OF TEACHING MATHEMATICS IN PRE PRIMARY SCHOOLS IN NAIROBI CITY COUNTY, KENYA

Music is a significant teaching strategy in early childhood education it improves development of young children’s self-confidence, self-esteem and their expression orally and mentally. Despite the fact that, use of music is a strategy that motivates and sustains children’s interest in the learning of mathematics, research studies in this area are scanty. The purpose of this study therefore was to find out influence of preschool teacher training on the use of music as a mode of teaching mathematics within Kasarani, Nairobi County. The study sought to determine the link between preschool teacher training and use of music in teaching mathematics. The descriptive survey research design was used to structure and guide the study. The study’s dependent variable was use of music as a medium of teaching mathematics while the independent variable was preschool teacher training in use of music in teaching mathematics. Random sampling was used to select 15 preschools out of the 30 targeted and purposive sampling used to select 15 head teachers out of 30 and 45 out of 90 preschool teachers. An observation guide and questionnaires were used to collect data for preschool teachers and head teachers. The study findings established a significant association between teacher training and use of music during mathematic instructions. The study concluded that preschool teachers in Kasarani Sub-County were using music to teach mathematics and that trained teachers used music to teach mathematics than their untrained counterparts. The study recommended the Kenya institute of curriculum development should come up with modules on step by step guidelines on how to teachers should integrate music during maths lessons.  Article visualizations

Combining school-catchment area models with geostatistical models for analysing school survey data from low-resource settings: Inferential benefits and limitations

School-based sampling has been used to inform targeted responses for malaria and neglected tropical diseases. Standard geostatistical methods for mapping disease prevalence use the school location to model spatial correlation, which is questionable since exposure to the disease is more likely to occur in the residential location. In this paper, we propose to overcome the limitations of standard geostatistical methods by introducing a modelling framework that accounts for the uncertainty in the location of the residence of the students. By using cost distance and cost allocation models to define spatial accessibility and in absence of any information on the travel mode of students to school, we consider three school catchment area models that assume walking only, walking and bicycling and, walking and motorized transport. We illustrate the use of this approach using two case studies of malaria in Kenya and compare it with the standard approach that uses the school locations to build geostatistical models. We argue that the proposed modelling framework presents several inferential benefits, such as the ability to combine data from multiple surveys some of which may also record the residence location, and to deal with ecological bias when estimating the effects of malaria risk factors. However, our results show that invalid assumptions on the modes of travel to school can worsen the predictive performance of geostatistical models. Future research in this area should focus on collecting information on the modes of transportation to school which can then be used to better parametrize the catchment area models

Confirmed Sighting of a Spawning Aggregation of the Brown-marbled Grouper, Epinephelus fuscoguttatus, in Kenya

The occurrence of spawning aggregations at fixed sites and times is well documented for several species of reef fish. These aggregations are known to attract fishers and such species may therefore be vulnerable to overfishing. This is particularly true in the case of groupers which have intrinsically vulnerable life history traits. The brown-marbled grouper, Epinephelus fuscoguttatus, distributed throughout the Indo-Pacific region and classified by IUCN as Near Threatened, is reported to form spawning aggregations but little is known about its spawning behaviour; in the Western Indian Ocean this has only been reported for the Seychelles. This study confirmed spawning aggregation behaviour in E. fuscoguttatus in Kenya based on underwater observations and fishers’ knowledge of the phenomenon. We showed that E. fuscoguttatus forms short aggregations for ~5 days linked to the new moon for a 3-4 month period during the northeast monsoon (austral summer).  The numbers of aggregating fish appear to be low, however, and the species is currently not managed in Kenya. Considering the fact that only small areas of the Kenyan coastline are under total protection (8.6% of the country’s coral reefs), these factors suggest that there is an urgent need for additional management of E. fuscoguttatus if it is to survive in Kenya

Influence of Organizational Demographics on the Relationship between Green Marketing Practices and Customer Satisfaction in the Soft Drink Industry in Nairobi Kenya

The objective of this study was to establish the influence of organizational demographics and Customer perception on the relationship between green marketing practices and Customer Satisfaction in the soft drink industry in Kenya. The specific objective was to establish the relationship between green marketing practices and Customer satisfaction in the Soft Drink industry in Nairobi Kenya. This study was anchored on consumer behavior theory and was guided by positivistic philosophy. The study adopted a descriptive cross-sectional research design to establish the influence of organizational demographics and customer perception on the relationship between green marketing practices and customer Satisfaction in the soft drink industry in Kenya. The study targeted a sample of 180 trade customers and 162 soft drink firms but, the researcher managed to successfully collect data from 130 of the trade customers and 102 soft drink firms. Since Cronbach’s Alpha is the most commonly used measure of co-efficient of internal consistency, the study adopted the same. Descriptive statistics (mean scores and measures of dispersion) and inferential statistics (correlation, analysis of variance and regression analysis) was conducted to determine the expected relationships between green marketing practices and customer satisfaction. The change in R2 due to the interaction term was 0.014 (0.396 - 0.382) and the interaction term was statistically significant (p < 0.05) and therefore the study accept hypothesis H2 that organizational demographics had a statistically significant moderating effect on the relationship between green marketing practices and customer satisfaction. Based on the overall study results obtained from the tests of the study hypotheses, it is concluded that organizational demographics had a statistically significant moderating effect on the relationship between green marketing practices and customer satisfaction

Spatial models for the rational allocation of routinely distributed bed nets to public health facilities in Western Kenya

BACKGROUND: In high to moderate malaria transmission areas of Kenya, long-lasting insecticidal nets (LLINs) are provided free of charge to pregnant women and infants during routine antenatal care (ANC) and immunization respectively. Quantities of LLINs distributed to clinics are quantified based on a combination of monthly consumption data and population size of target counties. However, this approach has been shown to lead to stock-outs in targeted clinics. In this study, a novel LLINs need quantification approach for clinics in the routine distribution system was developed. The estimated need was then compared to the actual allocation to identify potential areas of LLIN over- or under-allocation in the high malaria transmission areas of Western Kenya. METHODS: A geocoded database of public health facilities was developed and linked to monthly LLIN allocation. A network analysis approach was implemented using the location of all public clinics and topographic layers to model travel time. Estimated travel time, socio-economic and ANC attendance data were used to model clinic catchment areas and the probability of ANC service use within these catchments. These were used to define the number of catchment population who were likely to use these clinics for the year 2015 equivalent to LLIN need. Actual LLIN allocation was compared with the estimated need. Clinics were then classified based on whether allocation matched with the need, and if not, whether they were over or under-allocated. RESULTS: 888 (70%) public health facilities were allocated 591,880 LLINs in 2015. Approximately 682,377 (93%) pregnant women and infants were likely to have attended an LLIN clinic. 36% of the clinics had more LLIN than was needed (over-allocated) while 43% had received less (under-allocated). Increasing efficiency of allocation by diverting over supply of LLIN to clinics with less stock and fully covering 43 clinics that did not receive nets in 2015 would allow for complete matching of need with distribution. CONCLUSION: The proposed spatial modelling framework presents a rationale for equitable allocation of routine LLINs and could be used for quantification of other maternal and child health commodities applicable in different settings. Western Kenya region received adequate LLINs for routine distribution in line with government of Kenya targets, however, the model shows important inefficiencies in the allocation of the LLINs at clinic level