The Availability, Adequacy and Improvisation and the Use of Instructional Resources for Teaching Mathematics in Secondary Schools in West Pokot District, Kenya

This study examined the factors that influence the use of instructional resources/materials in the teaching of mathematics in secondary schools. Among the instructional materials that were investigated in their use are: Textbooks and mathematical tables. The study focused on their use in terms of their availability, adequacy and improvisation. The research design that was used in the study is descriptive survey. The research instruments included questionnaire, interview schedules and document analysis. The sampling techniques that were used in this research are stratified, simple random and purposive sampling. The respondents comprised 24 mathematics teachers and 372 form two students. Four teachers were interviewed. Data analysis was done by use of descriptive statistics. The study revealed that the selected instructional materials are not adequate. The main recommendations are that school administrators, teachers, students and parents should be sensitized on the importance of provision of instructional materials adequately. Keywords: Availability, Adequacy, Improvisation, Use and Instructional Resources (textbooks and mathematical tables)

Bridging Gender Disparities in Mathematics Achievement through Computer Based Learning

The purpose of this paper was to establish the influence of computer based learning (CBL) in Mathematics on learners’ achievement level in relation to gender. Specifically, the study sought to find out if there is any significant difference in achievement between boys and girls when exposed to CBL among secondary school students in Bungoma North District, Western Province, Kenya. This study was based on the theory of situated learning which states that learning as it normally occurs is a function of the activity, context and culture in which it occurs (Lave, 1988). The study adopted an experimental design where pre-test and post-test control group was used. The target population of the study was 1,173 form three secondary school students from Bungoma North District, Kenya. Purposive sampling was used to select schools with and without computers after which simple random sampling was used to select nine schools for the study. The study used a sample size of 240 respondents. Purposive sampling was used to select students who were computer literate then simple random sampling was applied to choose the respondents of the study. Mathematics achievement tests were used to collect data from the respondents. In data analysis both descriptive and inferential statistics were used. Descriptive statistics involved means, while inferential statistics utilized independent samples t-test. It was found out that there was no significant difference between boys and girls in Mathematics achievement when exposed to CBL. The paper therefore made the following recommendations: gender digital divide to be addressed, develop and use interactive Mathematics programmes, rural electrification to be continued, teachers to be equipped with the skills and knowledge they need to use the CBL technology, computer studies to be made compulsory in secondary schools. All this recommendations aim at bringing CBL into classroom to give every student, especially girls, a competitive edge in mathematics achievement. Keywords: Achievement, Bridging, Computer Based Learning, Gender Disparit

Processes to condition gas permeable membranes

Glassy-type gas separating membranes are conditioned to a state of enhanced permeability through controlled sorption of a selected conditioning gas such as CO.sub.2. Membranes are swelled to a state of plasticity without being rubberized and maintained in this state to allow their permeabilities to settle to a new, higher steady-state value. Upon depressurization, conditioned membranes exhibit enhanced permeability over untreated membranes, without serious loss of permselectivity. Membranes so conditioned must be maintained with a minimum sorption level of a conditioning or maintaining gas pending use to retain their improved characteristics.Board of Regents, University of Texas Syste

Pedagogical Factors Affecting Integration of Computers in Mathematics Instruction in Secondary Schools in Kenya

The paper reports findings of a study which sought to examine the pedagogical factors that affect the integration of computers in mathematics instruction as perceived by teachers in secondary schools in Kenya. This study was based on the Technology Acceptance Model (TAM). A descriptive survey design was used for this study. Stratified and simple random sampling techniques were used to select a sample of 200 teachers that was drawn independently and randomly from the stratum of secondary schools. Questionnaires, interview and observation schedules were used to collect data from respondents. Data was analyzed using descriptive statistics frequencies and percentages and inferential statistics including one way analysis of variance and regression analysis. The results indicate that mathematics teachers’ use of computer technology is significantly related to pedagogical factors such as knowledge and skills in computer, perceived usefulness, access to hardware and software and technical support and pedagogical routine practice. The study provides a basis upon which recommendations on appropriate remedies can be formulated to enhance the integration of computers in mathematics instruction by teachers. This also provides a guideline for the selection of sound instructional approaches in mathematics instruction in secondary schools. Keywords: ICT pedagogy, instructional software, mathematics classroom

RADIOAUTOGRAPHIC STUDIES OF PLAQUE-FORMING CELLS : I. ANTIGEN-STIMULATED PROLIFERATION OF PLAQUE-FORMING CELLS

A method has been described for obtaining radioautographs of plaque-forming cells. The method permits radioautographic analyses of small numbers of plaque-forming cells amidst large populations of non-plaque-forming cells. Spleen cells that were pulse-labeled with tritiated thymidine could be categorized readily as labeled or not labeled. Using this method it was found that (a) at least 55% of plaque-forming cells which appear 3 days after a maximal stimulus of 4 x 108 sheep red cells are still capable of DNA synthesis, and must have arisen by cell proliferation; (b) the rate of proliferation of plaque-forming cells is proportional to the log of the dose of antigen; (c) the S period of plaque-forming cells is at least 2 hr, appears to be constant, and is not influenced by antigen dose. The results suggest that antigen stimulates proliferation of plaque-forming cells by hastening their transit through the G1 phase of the generative cycle

Permeation of Several Gases through Elastomers, with Emphasis on the Deuterium/hydrogen Pair

The Diffusion and Permeation Coefficients for He, H2, D2, O2, and N2 in a Variety of Elastomers Were Measured by Simple Manometric Methods. the Elastomers Studied Were Butyl Rubber; Hypalon® 40 and 45; Viton® E60 and GF; Hydrin® 100 and Filled Hydrin® 100; Kraton® G, FG, and KG VTEOS; EPDM; Epoxidized Natural Rubber; and Neoprene. Consistent with Earlier Studies, Elastomers with Higher Glass Transition Temperatures Exhibited Lower Diffusion Coefficients. the Ratio of Diffusion Coefficients of the Hydrogen Isotope Pair Differed from the Purely Molecular‐weight‐based Prediction. Deuterium\u27s Slightly Smaller Size Relative to Hydrogen is Consistent with Observed Deviations from the Molecular‐weight‐based Diffusion Coefficient Ratio. © 1993 John Wiley & Sons, Inc. Copyright © 1993 John Wiley & Sons, Inc

Mentoring future Kenyan oncology researchers

This is a summary of the 1st Academic Model Providing Access to Healthcare (AMPATH) Oncology Institute research grant writing workshop organized in collaboration with the Kenya Medical Research Institute (KEMRI) and held in Kisumu, Kenya from January 16th to 18th, 2013. The goal of this meeting was to mentor future Kenyan scientists and prioritize research topics that would lead to improved cancer care and survival for the citizens of Kenya

Synthesis and characterization of hybrid organic-inorganic materials based on sulphonated polyamideimide and silica

The preparation of hybrid organic–inorganic membrane materials based on a sulphonated polyamideimide resin and silica filler has been studied. The method allows the sol–gel process to proceed in the presence of a high molecular weight polyamideimide, resulting in well dispersed silica nanoparticles (<50 nm) within the polymer matrix with chemical bonding between the organic and inorganic phases. Tetraethoxysilane (TEOS) was used as the silica precursor and the organosilicate networks were bonded to the polymer matrix via a coupling agent aminopropyltriethoxysilane (APTrEOS). The structure and properties of these hybrid materials were characterized via a range of techniques including FTIR, TGA, DSC, SEM and contact angle analysis. It was found that the compatibility between organic and inorganic phases has been greatly enhanced by the incorporation of APTrEOS. The thermal stability and hydrophilic properties of hybrid materials have also been significantly improved

Malaria in Kakuma refugee camp, Turkana, Kenya: facilitation of Anopheles arabiensis vector populations by installed water distribution and catchment systems

<p>Abstract</p> <p>Background</p> <p>Malaria is a major health concern for displaced persons occupying refugee camps in sub-Saharan Africa, yet there is little information on the incidence of infection and nature of transmission in these settings. Kakuma Refugee Camp, located in a dry area of north-western Kenya, has hosted ca. 60,000 to 90,000 refugees since 1992, primarily from Sudan and Somalia. The purpose of this study was to investigate malaria prevalence and attack rate and sources of <it>Anopheles </it>vectors in Kakuma refugee camp, in 2005-2006, after a malaria epidemic was observed by staff at camp clinics.</p> <p>Methods</p> <p>Malaria prevalence and attack rate was estimated from cases of fever presenting to camp clinics and the hospital in August 2005, using rapid diagnostic tests and microscopy of blood smears. Larval habitats of vectors were sampled and mapped. Houses were sampled for adult vectors using the pyrethrum knockdown spray method, and mapped. Vectors were identified to species level and their infection with <it>Plasmodium falciparum </it>determined.</p> <p>Results</p> <p>Prevalence of febrile illness with <it>P. falciparum </it>was highest among the 5 to 17 year olds (62.4%) while malaria attack rate was highest among the two to 4 year olds (5.2/1,000/day). Infected individuals were spatially concentrated in three of the 11 residential zones of the camp. The indoor densities of <it>Anopheles arabiensis</it>, the sole malaria vector, were similar during the wet and dry seasons, but were distributed in an aggregated fashion and predominantly in the same zones where malaria attack rates were high. Larval habitats and larval populations were also concentrated in these zones. Larval habitats were man-made pits of water associated with tap-stands installed as the water delivery system to residents with year round availability in the camp. Three percent of <it>A. arabiensis </it>adult females were infected with <it>P. falciparum </it>sporozoites in the rainy season.</p> <p>Conclusions</p> <p>Malaria in Kakuma refugee camp was due mainly to infection with <it>P. falciparum </it>and showed a hyperendemic age-prevalence profile, in an area with otherwise low risk of malaria given prevailing climate. Transmission was sustained by <it>A. arabiensis</it>, whose populations were facilitated by installation of man-made water distribution and catchment systems.</p

Polyimide hollow fiber membranes for CO2 separation from wet gas mixtures

Matrimid®5218 hollow fiber membranes were prepared using the dry-wet spinning process. The transport properties were measured with pure gases (H2, CO2, N2, CH4 and O2) and with a mixture (30% CO2 and 70% N2) in dry and wet conditions at 25 ºC, 50 ºC, 60 ºC and 75 ºC and up to 600 kPa. Interesting values of single gas selectivity up to 60 ºC (between 31 and 28 for CO2/N2 and between 33 and 30 for CO2/CH4) in dry condition were obtained. The separation factor measured for the mixture was 20% lower compared to the single gas selectivity, in the whole temperature range analyzed. In saturation conditions the data showed that water influences the performance of the membranes, inducing a reduction of the permeance of all gases. Moreover, the presence of water caused a decrease of single gas selectivity and separation factor, although not so significant, highlighting the very high water resistance of hollow fiber membrane modules