Investigating the wire fraction of the neuropil in primate cerebral ortex

D. Phil., School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, 2011Whether the neuropil is a static, optimally wired entity, whose components must be balanced in a certain way, is an open question. Are the proportions of the components of the neuropil consistent across different mammalian cortices, especially in primates where the cerebral cortex is complexly organized? This question is interesting because the actual biological underpinnings of complex behaviours and intelligence in big-brained primates remain enigmatic and why they seem qualitatively different from other animals in terms of their cognitive abilities. Understanding changes that may have occurred in the brain, especially at the level of neuropil organization, during the evolution in primates is important to our growing understanding of the intellectual abilities and behaviours exhibited by members of this group. The current series of quantitative studies was aimed at investigating variations in the proportionality of the “wire fraction” in three primate species, the olive baboon (Papio anubis), vervet monkey (Cercopithecus aethiops) and the common chimpanzee (Pan troglodytes), in a range of higher and lower order cortical areas, using a newly developed method that involves standard and immunohistochemical staining techniques to reveal and quantify the various profiles of the fine structures of the cerebral cortex. The results of these studies demonstrate clear layer differences in the wire fraction of the cerebral cortex, and for the most part, consistency in the neuropil wire fraction of the same layer across areas of the cerebral cortex within and between individuals of the same species; however, differences in the wire fraction of the neuropil were associated with changes in brain size. It is apparent that the neuropil is not static, as wiring “optimality” changes with layers and brain size and this has functional implications regarding neuronal processing and behavioural outcomes. The adaptive rationale adopted by evolutionary psychology studies to explain behaviours may be erroneous, as adaptation does not always explain sufficiently the emergence of complex behaviours related to brain size increases, especially in primates

Evaluation of taxation efficiency : a case study of Tanzania large scale mining sector.

ThesisLarge Scale Mining Sector (LSMS) in Tanzania is owned by foreign investors who are operating under Mineral Development Agreements (MDAs) and in the guidance of Environmental Impact Assessments (EIAs). The study entails to assess taxation efficiency in LSMS. The main source of revenue for public expenditure is taxation. Government of Tanzania (GOT) has ventured into allowing foreign direct investments (FDIs) in the mining sector for the purpose of ensuring that they achieve significant collections of revenues as taxes to improve the delivery of services to the public. The main problem is the failure and in some cases blatant refusal of the LSMS to pay statutory taxes to the GOT. The research is guided by three specific objectives, the first one being to determine the amounts and types of minerals mined and the amounts of taxes paid to GOT. Actual figures of taxes collected or paid were obtained from different sources of payments, including Tanzania Mineral Audit Agency (TMAA), Tanzania Revenue Authority (TRA), Ministry of Energy and Minerals (MEM), and Mines Head Offices. All data were secondary. The second specific objective was to determine statutory types and amounts of taxes to be paid by LSMS and the cause of failure or refusal to pay taxes to GOT. This was done by going through Mining Acts and Mineral Policies of the time in question, and listing all types and amounts of taxes the LSMS were statutorily required to pay to GOT. The data was also secondary. Primary data was collected through a questionnaire in five selected mines. The sample size is 100 respondents at a rate of 20 respondents for each mine. The third specific objective was to propose or suggest what should be done to improve tax collection from LSMS. This was done by going through two scenarios, namely: literature review and referring to other countries with a success in mineral tax benefits. The significance of the study is to provide relevant information for LSMS taxpayers and GOT policy makers to merge on the understanding pertaining to tax compliance. Both qualitative and quantitative data analysis (descriptive and inferential) methods were applied in analyzing the data for achieving the specific objectives one and two. From the research it has been found that the outcry is genuine. The LSMS was not paying out many, if not all, deeds they were supposed to pay. There are no genuine excuses for failure or refusal to pay their dues (taxes). Major conclusion from the research includes: LSMS in Tanzania has blatantly refused to pay Corporate/Income Tax, LSMS evaded and avoided paying taxes, Taxation Efficiency is on average (1.2 to 5 %) which is 3.10%. Operating cost was pegged at 70% of the sales value. GOT has no capability and capacity to collect mineral taxes and other mineral dues. It is recommended that Tanzania should control and manage her mineral resources so as to realize economic and social development from tax revenues by: -Publicizing MDA’s: This will enable the public to comment on them especially through the Parliament Abolishing ring fencing in all mines: This will make it easier to control costs of operating the mines. Making accounting currency to be a United States Dollar: To avoid or reduce inflation of the local currency. Implementing Mineral Resource Rent Tax Act (MRRTA): To manage production and sales of final products and hence a better taxation efficiency is achieved The study further enhances the contribution of knowledge on the respective field study whereas it serves as the foundation of knowledge for further studies in the future. There is little control for achieving true figures, be it production, pricing, expenditure and profits before tax. This study may be for a bigger area like East and Central Africa, before looking at the African Continent at large

Coenzyme Q10 Protect Mice Against Inflammatory Responses During Experimental Cerebral Malaria

Malaria is a life threatening infectious diseases transmitted by the bite of infected female Anopheles mosquito and responsible for high morbidity and mortality rates. Cerebral malaria is a complex neurological syndrome, whose pathology is mediated by inflammatory processes triggered by the immune system of the host following infection with Plasmodium falciparum. Coenzyme Q10 is an obligatory cofactor in the electron transport chain. The reduced form of Coenzyme Q10 serves as a potent antioxidant additionally; Coenzyme Q10 has been identified as a modulator of gene expression, inflammation and apoptosis. However, the modulatory effects of Coenzyme Q10 Plasmodium berghei ANKA infection process and risk occurrence of experimental cerebral malaria (ECM) have not been determined. The aim of this study was to elucidate the putative impact of oral administration of Coenzyme-Q10 on the initiation or regulation of inflammatory immune response in ECM of C57BL/6 mice during Plasmodium berghei ANKA (PbA) infection. We observed that oral administration of Coenzyme-Q10 both before and after PbA infection significantly hampered infiltration of inflammatory monocytes into the brain. Furthermore, pro-inflammatory cytokine TNF-α, which is associated with inflammation during ECM, was down-regulated in Coenzyme-Q10 administered mice. Remarkably, Coenzyme-Q10 was very effective in inhibiting dendritic cell differentiation. These data collectively demonstrated the immuno-modulatory function of Coenzyme-Q10 on host inflammatory responses during ECM. Keywords: Plasmodium berghei ANKA, Coenzyme Q10, experimental cerebral malaria DOI: 10.7176/JNSR/9-2-05

Tracing the origins of rescued chimpanzees reveals widespread chimpanzee hunting in Cameroon

<p>Abstract</p> <p>Background</p> <p>While wild chimpanzees are experiencing drastic population declines, their numbers at African rescue and rehabilitation projects are growing rapidly. Chimpanzees follow complex routes to these refuges; and their geographic origins are often unclear. Identifying areas where hunting occurs can help law enforcement authorities focus scarce resources for wildlife protection planning. Efficiently focusing these resources is particularly important in Cameroon because this country is a key transportation waypoint for international wildlife crime syndicates. Furthermore, Cameroon is home to two chimpanzee subspecies, which makes ascertaining the origins of these chimpanzees important for reintroduction planning and for scientific investigations involving these chimpanzees.</p> <p>Results</p> <p>We estimated geographic origins of 46 chimpanzees from the Limbe Wildlife Centre (LWC) in Cameroon. Using Bayesian approximation methods, we determined their origins using mtDNA sequences and microsatellite (STRP) genotypes compared to a spatial map of georeferenced chimpanzee samples from 10 locations spanning Cameroon and Nigeria. The LWC chimpanzees come from multiple regions of Cameroon or forested areas straddling the Cameroon-Nigeria border. The LWC chimpanzees were partitioned further as originating from one of three biogeographically important zones occurring in Cameroon, but we were unable to refine these origin estimates to more specific areas within these three zones.</p> <p>Conclusions</p> <p>Our findings suggest that chimpanzee hunting is widespread across Cameroon. Live animal smuggling appears to occur locally within Cameroon, despite the existence of local wildlife cartels that operate internationally. This pattern varies from the illegal wildlife trade patterns observed in other commercially valuable species, such as elephants, where specific populations are targeted for exploitation. A broader sample of rescued chimpanzees compared against a more comprehensive grid of georeferenced samples may reveal 'hotspots' of chimpanzee hunting and live animal transport routes in Cameroon. These results illustrate also that clarifying the origins of refuge chimpanzees is an important tool for designing reintroduction programs. Finally, chimpanzees at refuges are frequently used in scientific investigations, such as studies investigating the history of zoonotic diseases. Our results provide important new information for interpreting these studies within a precise geographical framework.</p

L'internationalisation dans les écoles supérieures de management françaises

This research on the process of internationalization of French business schools finds its anchor in the strategic management mainstream of research. The aim of the thesis is to understand the underlying phenomena behind the design and implementation of an international strategy. Through observing and studying the practices of actors in public and private business schools, we were able to point out that those schools address strategy through the process of effectuation. As a matter of fact, strategy is a result of practice and managers formalize what they will call strategy based on the means they have at their disposal.The study shows that effectuation manifests itself in private and public business schools differently since each category of school has its own specificities. The ambition of this work is to shed some light on what is actually called internationalization in french business schools and the process through which decision are made in those organizations. Besides, the thesis invites us to go beyond the traditional opposition between universities and business schools in France. It is time to think about consolidating and/or developing cooperation between the two types of higher education institutions.Cette recherche sur l’internationalisation dans les écoles supérieures de management françaises s’inscrit dans le courant du management stratégique, en interrogeant les phénomènes qui sous-tendent la conception et la mise en œuvre de la stratégie.L’approche par l’observation et le décodage des pratiques des acteurs des écoles universitaires et des écoles de management privées, indique que les écoles de milieu de classement en France se développent à l’international suivant un processus émergent, basé sur des phénomènes d’effectuation.L’effectuation qui représente la capacité des acteurs à prendre des décisions en fonction des moyens dont ils disposent, se manifeste différemment selon qu’on est dans une école de management privée ou dans une école de management publique, compte tenu des spécificités de chaque environnement.Cette thèse à la fois descriptive et compréhensive, invite à questionner les idées reçues sur l’opposition entre universités et grandes écoles en France, et met en avant la dichotomie qui peut exister entre discours et pratiques lorsqu’il s’agit d’internationalisation et surtout de conception et de mise en oeuvre de la stratégie

Internationalization in French business schools

Cette recherche sur l’internationalisation dans les écoles supérieures de management françaises s’inscrit dans le courant du management stratégique, en interrogeant les phénomènes qui sous-tendent la conception et la mise en œuvre de la stratégie.L’approche par l’observation et le décodage des pratiques des acteurs des écoles universitaires et des écoles de management privées, indique que les écoles de milieu de classement en France se développent à l’international suivant un processus émergent, basé sur des phénomènes d’effectuation.L’effectuation qui représente la capacité des acteurs à prendre des décisions en fonction des moyens dont ils disposent, se manifeste différemment selon qu’on est dans une école de management privée ou dans une école de management publique, compte tenu des spécificités de chaque environnement.Cette thèse à la fois descriptive et compréhensive, invite à questionner les idées reçues sur l’opposition entre universités et grandes écoles en France, et met en avant la dichotomie qui peut exister entre discours et pratiques lorsqu’il s’agit d’internationalisation et surtout de conception et de mise en oeuvre de la stratégie.This research on the process of internationalization of French business schools finds its anchor in the strategic management mainstream of research. The aim of the thesis is to understand the underlying phenomena behind the design and implementation of an international strategy. Through observing and studying the practices of actors in public and private business schools, we were able to point out that those schools address strategy through the process of effectuation. As a matter of fact, strategy is a result of practice and managers formalize what they will call strategy based on the means they have at their disposal.The study shows that effectuation manifests itself in private and public business schools differently since each category of school has its own specificities. The ambition of this work is to shed some light on what is actually called internationalization in french business schools and the process through which decision are made in those organizations. Besides, the thesis invites us to go beyond the traditional opposition between universities and business schools in France. It is time to think about consolidating and/or developing cooperation between the two types of higher education institutions

L'internationalisation dans les écoles supérieures de management françaises

This research on the process of internationalization of French business schools finds its anchor in the strategic management mainstream of research. The aim of the thesis is to understand the underlying phenomena behind the design and implementation of an international strategy. Through observing and studying the practices of actors in public and private business schools, we were able to point out that those schools address strategy through the process of effectuation. As a matter of fact, strategy is a result of practice and managers formalize what they will call strategy based on the means they have at their disposal.The study shows that effectuation manifests itself in private and public business schools differently since each category of school has its own specificities. The ambition of this work is to shed some light on what is actually called internationalization in french business schools and the process through which decision are made in those organizations. Besides, the thesis invites us to go beyond the traditional opposition between universities and business schools in France. It is time to think about consolidating and/or developing cooperation between the two types of higher education institutions.Cette recherche sur l’internationalisation dans les écoles supérieures de management françaises s’inscrit dans le courant du management stratégique, en interrogeant les phénomènes qui sous-tendent la conception et la mise en œuvre de la stratégie.L’approche par l’observation et le décodage des pratiques des acteurs des écoles universitaires et des écoles de management privées, indique que les écoles de milieu de classement en France se développent à l’international suivant un processus émergent, basé sur des phénomènes d’effectuation.L’effectuation qui représente la capacité des acteurs à prendre des décisions en fonction des moyens dont ils disposent, se manifeste différemment selon qu’on est dans une école de management privée ou dans une école de management publique, compte tenu des spécificités de chaque environnement.Cette thèse à la fois descriptive et compréhensive, invite à questionner les idées reçues sur l’opposition entre universités et grandes écoles en France, et met en avant la dichotomie qui peut exister entre discours et pratiques lorsqu’il s’agit d’internationalisation et surtout de conception et de mise en oeuvre de la stratégie

Linking the Community with Low Interest Rate Micro Credits Providers-The Case of Makongo Kinondoni Municipal

Makongo ward is a peri-urban area located 15km outside of Dar es Salaam city center, which is found in the Kinondoni Municipality. Community needs assessment was conducted to identify problems, needs, and strengths in a community using a questionnaire as the main method which was supplemented with interview, listening, community mapping and focus group discussions. The research findings revealed that there were many problems facing the Makongo community. At the top of the list was the low income earners need to access to low interest rate micro credits. The findings show that there were various micro credit providers but their interest rate are very high making difficult for economic development of a common man. While in despair they did not know what to do. The researcher spoke to the community so as to make the need known. After some advocacy and training the project to link the community with low interest rate micro credits providers came into being. Four Training workshops were organized and 150 participants attended the training. Brochures were distributed and there was a good response, 120 formed three groups of 40 members each, accessed micro credits at low rate and are still accessing

Systèmes différentiels extérieurs et applications aux problèmes inverses

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