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Influence of Temperature on the Interaction for Resource Utilization Between Fall Armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), and a Community of Lepidopteran Maize Stemborers Larvae
Full text linkIntra- and interspecific interactions within communities of species that utilize the same resources are characterized by competition or facilitation. The noctuid stemborers, Busseola fusca and Sesamia calamistis, and the crambid stemborer, Chilo partellus were the most important pests of maize in sub-Saharan Africa before the recent "invasion" of fall armyworm (FAW), Spodoptera frugiperda, which currently seriously limits maize yields in Africa. This new pest is interacting with the stemborer community at the larval stage in the use of maize resources. From a work done by Ntiri et al. [13] on the influence of temperature on the larval intra- and interspecific resources utilization within the community of Lepidoptera stemborers involving B. fusca, S. calamistis, and C. partellus, there is a need to update this study by adding the new pest, S. frugiperda, in order to understand the effect of temperature on the larval interactions of all these four species under the context of climate change. The influence of temperature on intra- and interspecific larval interactions was studied in the same protocol of Ntiri et al. [13] using artificial stems kept at different constant temperatures (15 °C, 20 °C, 25 °C, and 30 °C) in an incubator and assessing survival and relative growth rates of each species in single and multi-species experiments. After the inclusion of FAW into the experiments, with regard to relative growth rates, both intra- and interspecific competition was observed among all four species. With regard to survival rates, cannibalism can also explain the intra- and interspecific interactions observed among all four species. Interspecific competition was stronger between the stemborers than between the FAW and the stemborers. Similar to lepidopteran stemborers, temperature affected both survival and relative growth rates of the FAW as well. Regardless of the temperature, C. partellus was superior in interspecific interactions shown by higher relative growth and survival rates. The results suggest that the FAW will co-exist with stemborer species along entire temperature gradient, though competition and/or cannibalism with them is weak. In addition, temperature increases caused by climate change is likely to confer an advantage to C. partellus over the fall armyworm and the other noctuids
A Comparison of Two DNA Metagenomic Bioinformatic Pipelines While Evaluating the Microbial Diversity in Feces of Tanzanian Small Holder Dairy Cattle
No full textAnalysis of shotgun metagenomic data generated from next generation sequencing platforms can be done through a variety of bioinformatic pipelines. These pipelines employ different sets of sophisticated bioinformatics algorithms which may affect the results of this analysis. In this study, we compared two commonly used pipelines for shotgun metagenomic analysis: MG-RAST and Kraken 2, in terms of taxonomic classification, diversity analysis, and usability using their primarily default parameters. Overall, the two pipelines detected similar abundance distributions in the three most abundant taxa Proteobacteria, Firmicutes, and Bacteroidetes. Within bacterial domain, 497 genera were identified by both pipelines, while an additional 694 and 98 genera were solely identified by Kraken 2 and MG-RAST, respectively. 933 species were detected by the two algorithms. Kraken 2 solely detected 3550 species, while MG-RAST identified 557 species uniquely. For archaea, Kraken 2 generated 105 and 236 genera and species, respectively, while MG-RAST detected 60 genera and 88 species. 54 genera and 72 species were commonly detected by the two methods. Kraken 2 had a quicker analysis time (~4 hours) while MG-RAST took approximately 2 days per sample. This study revealed that Kraken 2 and MG-RAST generate comparable results and that a reliable high-level overview of sample is generated irrespective of the pipeline selected. However, Kraken 2 generated a more accurate taxonomic identification given the higher number of “Unclassified” reads in MG-RAST. The observed variations at the genus level show that a main restriction is using different databases for classification of the metagenomic data. The results of this research indicate that a more inclusive and representative classification of microbiomes may be achieved through creation of the combined pipelines
Strategy typology, organizational factors and performance of freight forwarding companies in Kenya
No full textThe aim of this study was to determine whether organizational factors had
an intervening effect on the relationship between strategy typology and
organizational performance. Organizational factors which comprise of
shared values, skills and systems enable companies to adapt the correct
strategy and direct the conduct of their business to achieve superior
performance. The research was based on Resource based theory which
postulates that firm resources consist of assets, capabilities, competences and
definitive techniques among other organizational factors. The firm resources
enable the firm to formulate and implement strategies that are aimed at
enhancing organizational performance. Positivism research philosophy and
descriptive cross-sectional survey were used in this study. Stratified random
sampling was applied to obtain a study sample of 120 freight forwarding
firms. Primary data was collected using semi-structured questionnaires. Data
was analyzed using regression analysis. The results of the study showed that
there was a significant influence of strategy typology on organizational
performance. However, the study found that organizational factors have no
significant intervening influence on the relationship between strategy
typology and organizational performance. This indicates that the
management should consider enhancing skills of their human resources and
instill the virtues of shared values across various organizational functions.
Also, develop systems that are endowed with technology that would ensure
seamless flow of communication that enhances firm performance
Management of Maxillofacial Osteosarcomas in Kenya
No full textBackground: Though not common, maxillofacial osteosarcomas present a unique challenge in management due to a multitude of factors, such as difficulty in diagnosis and local complex anatomy, making surgical excision difficult as well as debate necessary on the usefulness of adjunct treatment modalities, such as chemotherapy and radiotherapy. Nonetheless, osteosarcomas are a significant health burden because of their high morbidity and mortality.
Method: Retrospective cross-sectional study of records archived in the School of Dental Sciences, University of Nairobi. Results: 25 cases of maxillofacial sarcomas were seen over 26 years. Mean age of occurrence was 35.68 years with a preponderance for females (17 cases). The mandible was the most affected site, accounting for 18 cases.
Discussion: The management of maxillofacial sarcomas in our setting presents significant challenges arising from multiple factors such as lack of standardised treatment protocol, late presentation of patients, diagnostic challenges and loss to follow-up
Valve distribution of the popliteal vein: A structural basis for deep venous thrombosis?
No full textObjective: To describe the relationship between number and distribution of valves. Methods: Sixty-six popliteal vein specimens were used for the study after routine dissection at the Department of Human Anatomy, University of Nairobi. The extents of the popliteal vein were identified at the adductor hiatus and soleal arch, cut at these points and then longitudinally sliced open. The number and distribution of valves were then recorded. Data were presented using photomacrographs and tables. Results: The median number of valves was 1 (mean 0.8; range 0–2), with the lower part of the popliteal vein as the most consistent valve position. Most striking was the valve absence noted in 27 (41%) of the veins. Conclusion: These findings suggest that a significant proportion of popliteal veins do not have valves thus providing a credible structural link that may predispose the popliteal vein to deep venous thrombosis in the study populatio
A review of Kenya’s cancer policies to improve access to cancer testing and treatment in the country
Full text linkBACKGROUND:
Cancer is the third-leading cause of mortality in Kenya, resulting in unique challenges to the country's health system. An increase in the number of cancer cases in Kenya over the past decade resulted in legislative actions and policies to guide delivery of cancer services. Kenya's new national cancer control strategy and past policy efforts provide an opportunity to synergise information and enhance understanding to improve cancer diagnosis and treatment in the country. The objectives of this study are to (1) document policy-modifiable factors based on a review of policy documents and results of a key informant survey and (2) develop recommendations to improve policies affecting cancer testing and treatment services in Kenya. This study builds upon our previous study Improving Access to Cancer Testing and Treatment in Kenya (Makau Barasa et al. J Global Oncol 2(216), 2017).
METHODS:
The study applied an in-depth systematic review of Kenya's cancer policies and guidelines, a qualitative analysis of results from a section of a semi-structured key informant survey focused on the opinions of clinicians delivering cancer services as well as cancer support groups and advocacy leaders, and a stakeholder analysis identifying key policy-makers and implementers. Details of the complete key informant survey were published in our previous study.
RESULTS:
Kenya's cancer policies have guided progress made in providing the legal and implementation frameworks for the development and delivery of cancer services at the national and county levels. Some policy implementation gaps are noted. These include inadequate financing for cancer services, limited research and data to support policy formulation, and the concentration of cancer services in urban areas. The key informant survey identified policy-modifiable actions that can address some of the gaps and improve the delivery of and access to cancer testing and treatment services in the country. Some of these include addressing the financial barriers affecting cancer testing and treatment services; increasing stakeholder engagement in training health personnel to deliver cancer testing and treatment services; decentralising cancer services and improving cancer surveillance and research; and increasing education and awareness about cancer symptoms, screening procedures and treatment options. A set of priority policy actions were selected from the study findings and used to develop recommendations for Kenya's policy-makers and stakeholders.
CONCLUSIONS:
Revisions to Kenya's cancer policies are seeking to address gaps noted in past policies and to improve access to cancer testing and treatment in Kenya. However, based on study findings, additional actions can be taken to strengthen policy implementation. Considering the policy formulation and implementation process and costs, this study recommends focusing on three priority policy actions that can have significant impact on improving access to cancer testing and treatment services. These include addressing financing, insurance and human resources gaps; increasing stakeholder engagement; and decentralising health services for better surveillance and data to inform policie
Prospects and constraints in smallholder farmers' adoption of multiple soil carbon enhancing practices in Western Kenya
No full textMost smallholder farmers in sub-Saharan Africa (SSA) are adversely affected by low soil fertility, land degradation and climate change-related shocks such as drought. These problems lead to low productivity and low household income. In addition, the adoption of soil carbon enhancing practices remains low in Western Kenya. This study analyses the factors that influence the probability and extent of adoption of soil carbon enhancing practices in Western Kenya utilizing plot-level information, socioeconomic characteristics and external supporting factors. Multivariate probit model and generalized ordered logit were utilized to assess the adoption of multiple soil carbon enhancing practices and the extent of adoption respectively. Results indicate that the adoption of soil carbon enhancing practices is correlated, suggesting interrelation in farmers' adoption decisions. Both the multivariate probit model and generalized ordered probit results indicate that the probability and extent of adoption of soil carbon enhancing practices are influenced by plot-level characteristics, literacy level, access to agricultural credit, agricultural group membership, participation in the market, and gender of the household