109 research outputs found

    Radiation exposure in interventional procedures

    Get PDF
    The aim of this study was to estimate radiation doses patients and staff are exposed to during interventional procedures (IPs), compare them with the international diagnostic reference levels and to develop initial National Diagnostic Reference Levels. The IP survey was undertaken as the initial task of which, retrospective data were collected from the only four Kenyan hospitals carrying out interventional radiology and cardiology procedures at the time of the study. Real-time measurement of radiation dose to patients and staff during these procedures was done. To the patients, kerma-area product (KAP) and fluoroscopy time measurements were done using an in-built KAP meter, while peak skin dose (PSD) was measured using slow Extended Dose Range (EDR2. ®) radiographic films. The staff occupational doses were measured using individual thermoluminescence dosemeters. The maximum and minimum KAP values were found to be 137.1 and 4.2 Gy cm. 2, while the measured PSD values were 740 and 52 mGy, respectively. The fluoroscopic time range was between 3.3 and 70 min. The staff doses per procedure ranged between 0.05 and 1.41 mSv for medical doctors, 0.03 and 1.16 mSv for nurses, 0.04 and 0.78 mSv for radiographers and 0.04 and 0.88 mSv for clinical staff. The measured patient PSDs were within the threshold limit for skin injuries. However, with the current few IP specialists, an annual increase in workload as determined in the study will result in the International Commission on Radiation Protection annual eye lens dose limit being exceeded by 10 %. A concerted effort is required to contain these dose levels through use of protective gear, optimisation of practice and justification

    The State of Agricultural Mechanisation in Uasin Gishu District, Kenya, and its Impact on Agricultural Output

    Get PDF
    Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): The State of Agricultural Mechanisation in Uasin Gishu District, Kenya, and its Impact on Agricultural Output. Invited Overview. Vol. IX. June, 2007

    Diversity and Taxonomic Identity of Rumen Bacterial Community in Cattle Fed Different Diets

    Get PDF
    In this study, the identity of rumen bacterial community and their taxonomic classification in Zebu heifers (n=24) fed 4 different diets (range grasses, Bracharia MulatoII, Azolla and Cassava leaf meal) was surveyed using metagenomics sequencing of the 16SrRNA gene. Rumen liquor samples were collected from the heifers from which a total of 192 DNA samples were amplified and the resulting 16S rRNA sequences compared to the existing sequences at the National Centre for Biotechnology Information (NCBI) BLAST database through the MetagenAssist . Bioinformatics analyses indicated that 17 operational taxonomic units (OTUs) were present at the phylum level. Of these, 43.3% were affiliated to the phylum Firmicutes, 27.2% Bacteroidetes, 22.8% Proteobacteria and 1.7% Euryarchaeota. The remaining were Cyanobacteria (1.4%), Chloroflexi (1%) while Actinobacteria, Verrucomicrobia, Spirochaetes, Tenericutes, Planctomycetes, Elusimicrobia, Lentisphaerae, Armatimonadetes, Fibrobacteres, Synergistetes and Arthropoda were all below 1%. Both Time and Diet had significant effect on the abundance of microbes but did not affect their diversity. Different diets therefore can affect the abundance of rumen microbiome and eventually the performance of animals

    Distribution, characterization and the commercialization of elite Rhizobia strains in Africa

    Get PDF
    Grain legumes play a significant role in smallholder farming systems in Africa because of their contribution to nutrition and income security and their role in fixing nitrogen. Biological Nitrogen Fixation (BNF) serves a critical role in improving soil fertility for legumes. Although much research has been conducted on rhizobia in nitrogen fixation and their contribution to soil fertility, much less is known about the distribution and diversity of the bacteria strains in different areas of the world and which of the strains achieve optimal benefits for the host plants under specific soil and environmental conditions. This paper reviews the distribution, characterization, and commercialization of elite rhizobia strains in Africa

    The development of bone char-based filters for the removal of flouride from drinking water

    Get PDF
    Millions of people rely on drinking water that contains excess fluoride. Only few fluoride removal techniques have been implemented on a wider scale in low and middle income countries. One of these methods, bone char filtration, is highly efficient. However, its lifespan is rather limited. This paper presents first laboratory results and field testing of a new fluoride removal technology, based on a combination of bone char and calcium-phosphate pellets. These chemicals are slowly released to the water for fluoride precipitation. Although this method, commonly referred to as contact precipitation is known, the development of such pellets is new. Fixed-bed laboratory experiments show that this mixture of materials can increase filter uptake capacity by a factor of 3 and more. However, to reduce the phosphate concentration in the treated water, the design of full-scale community filters for field testing has to be slightly modified

    Weight gain and enteric methane production of cattle fed on tropical grasses

    Get PDF
    Context: Planted grasses are becoming an increasingly important feed resource for tropical smallholder ruminant production; yet, limited research has been conducted to quantify productivity or enteric methane (CH4_4) production of animals consuming these grasses. Aim: An experiment was conducted to assess yields and nutritional attributes of the following three tropical grasses: Cenchrus purpureus var. Kakamega 1 (Napier), Chloris gayana var. Boma (Rhodes) and Urochloa brizantha var. Xaeres (Brachiaria), and quantify enteric CH4_4 production of cattle fed on them. Methods: Yearling Boran steers (n:18; initial liveweight 216 ± 5.8 kg (mean ± s.e.m.) were allocated to one of three grasses, in a completely randomised design and fed ad libitum for two feeding periods, each period lasting for 70 days. Intake, liveweight (LW), apparent total-tract digestibility and enteric CH4_4 production were assessed. The grasses used were grown on site and biomass yields were monitored over a 2-year period. Animal growth was also simulated to a final weight of 350 kg, and the amount of feed and size of land required to produce, and days to reach final weight, were estimated. Key results: Mean voluntary dry-matter intake (DMI) and ADG were higher (P 0.05) within period. Methane yield (MY; CH4_4 g/DMI kg) was similar among treatments (26.7–28.5, P = 0.26) but Napier had a higher CH4_4 conversion factor [Ym; CH4_4 (MJ)/gross energy intake (MJ)] than did Rhodes and Brachiaria (0.0987 vs 0.0873 and 0.0903 respectively; P = 0.013). Our modelling indicated that steers consuming Rhodes took at least 30 more days to reach the target LW, required larger land area for feed production and produced more enteric CH4_4 than did the other two diets. Conclusion: Even though animal performance and MY among treatments did not differ, the animals had higher MY and Ym_m than currently estimated by the Intergovernmental Panel on Climate Change. Implication: The three grasses supported similar animal growth rate, implying that growing of higher-yielding grasses such as Napier offers an opportunity to optimise land productivity in the tropics. However, suitable feeding practices such as protein supplementation need to be explored to enhance ruminant production and reduce enteric CH4_4 production

    Flowering and maturation periods of Finger Millet as influenced by phosphorus and variety in different agro-ecologies in Kenya

    Get PDF
    Phosphorus is important for finger millet production in many tropical African soils with low phosphorus fertility. Knowledge of redirection of this limited resource for reproduction is fundamental in realization of potential yields. The effect of four phosphorus levels (0, 12.5, 25.0 and 37.5 kg ha-1 P2O5) and three varieties (U-15, P-224 and a local check) on the days to flowering and maturity of finger millet were evaluated in three agro-ecologies in Kenya during the raining seasons of 2014-2015. Phosphorus application significantly (P<0.05) increased early flowering and physiological maturity in Kakamega and Busia. The varieties elicited significantly different days to 50% flowering and maturation periods in all the study sites. The days to flowering and maturity were found to be lowly but negatively correlated with the grain yield of finger millet in all the sites

    Phosphorus influence on nitrogen uptake, nutrient and yield attributes of finger millet in semi-arid region of Kenya

    Get PDF
    An understanding of P efficiencies of finger millet is very important in soil management and selection of varieties adaptable to P-deficient soils. Therefore, on-station experiments were conducted at the ICRISAT-Kiboko research station to evaluate the effect of differential levels of P on nitrogen uptake, nutrient content and yield. There were four P levels (0, 12.5, 25 and 37.5 kg ha-1 P2O5) and three varieties (U-15, P-224 and Ekalakala). Ekalakala was the local check while 0 kg/ha P2O5 was the control. The trial was laid out in a randomized complete block design in factorial arrangement with three replicates. Soil analytical results showed moderately available P but very low N, organic carbon and zinc. Significant differences (P<.05) were observed between the phosphate levels on the nitrogen contents, where the control had the lowest with 4.95% and 4.90% for the short and long rains respectively; while the 25 kg ha-1 P2O5 rate had the highest, with 5.66% in the short rains and 5.14% in the long rains. The protein content significantly increased with phosphorus application, peaking at 11.00 g/100 g on the 25 kg ha-1 P2O5treatment. The newly released variety (U-15) responded positively to P supplemented at 25 kg ha-1 P2O5 , with a maximum grain yield of 3,410 kg ha-1. It can, thus, efficiently utilize N in soils with low N and is highly recommended. The application of P beyond 25 kg ha-1 P2O5 would not be translated into profitable yields, but losses to the farmer
    • …
    corecore