A study of charged particles/radiation damage to VLSI device materials

Future spacecraft systems such as the manned space station will be subjected to low-dose long term radiation particles. Most electronic systems are affected by such particles. There is therefore a great need to understand device physics and failure mechanisms affected by radiation and to design circuits that would be less susceptible to radiation. Using 2 MeV electron radiation and bias temperature aging, it was found that MOS capacitors that were prepositively biased have lower flatband voltage shift and lesser increase in density of surface state charge than those that were not prepositively biased. In addition, it was shown that there is continued recovery of flatband voltage and density of state charge in irradiated capacitors during both room temperature anneal and 137 degree anneal. When nMOS transistors were subjected to 1 MeV proton radiation, charge pumping and current versus voltage measurements indicated that transconductance degradation, threshold voltage shifts and changes in interface states density may be the primary cause of nMOS transistor failure after radiation. Simulation studies using SPICE were performed on CMOS SRAM cells of various transistor sizes. It is shown that transistor sizing affects the noise margins of CMOS SRAM cells, and that as the beta ratio of the transistors of the CMOS SRAM cell decreases, the effective noise margin of the SRAM cell increases. Some suggestions were made in connection with the design of CMOS SRAMS that are hardened against single event upsets

Rebuilding after emergency: Revamping agricultural research in Sierra Leone after civil war

"The civil war in Sierra Leone, caused by a mix of political, social, and economic factors, had a huge impact on the overall economy in general and on the performance of the agricultural sector in particular. The agricultural research system of Sierra Leone was severely affected by the civil war. Research infrastructure was destroyed, laboratories were damaged and abandoned, and well-trained researchers and scientists fled from the country. With the cessation of hostilities in 2002, the government of Sierra Leone concentrated its efforts on the resettlement of displaced persons and on social and economic reconstruction. The efforts of the government include the rehabilitation and reorganization of the former National Agricultural Research Coordinating Council (NARCC), which was coordinating agricultural research in Sierra Leone. The Sierra Leone Agricultural Research Institute (SLARI) Act was passed by the parliament of Sierra Leone in 2007 to replace NARCC. As a new organization, SLARI needed to make strategic decisions to guide its operations in order to make it effective in responding to the demands of stakeholders within the food and agriculture system. To provide a focus for SLARI and link its agenda to national development priorities, a strategic plan and operational plan were developed. The methodology used to design the SLARI strategic plan applied an organizational innovation model through which the plan was nested within the strategic plan of the Forum for Agricultural Research in Africa (FARA) and Conseil Ouest et Center Africain pour la Recherche et le Développement Agricoles (CORAF) / West and Central African Council for Agricultural Research and Development (WECARD), and the operational plan was hinged on Comprehensive African Agricultural Development Program (CAADP) and Framework for African Agricultural Productivity (FAAP) principles. This would ensure synergy with regional and subregional strategies. The strategic plan would promote increased coordination, interaction, interlinkages, partnerships, and networks among the various agents associated with agricultural research for development systems in Sierra Leone. It would also help achieve SLARI's vision of increasing food security and wealth among Sierra Leone's rural population. For SLARI to make a meaningful contribution to agricultural development in Sierra Leone, the operational plan must be implemented in such a way that the results envisaged in the strategic plan can be achieved. This requires funds and commitment from all stakeholders, especially the government of Sierra Leone." from authors' abstractwar, Agriculture, Development, Research, Strategic plan, Operational plan, Science and technology, Agricultural research,

Institutional and public expenditure review of Ghana’s Ministry of Food and Agriculture

The need for agricultural ministries to have the capacity to develop appropriate policies and effectively implement them is becoming increasingly important as African countries, following on their commitment to Comprehensive Africa Agriculture Development Program (CAADP), pursue economic growth through agriculture-led development. The ministries need to take the lead in pulling together evidence based strategies and building partnerships that ensures their ownership. As donors begin to align their policies with those of governments, an increasingly large share of external support to agriculture is likely to be delivered in the form of support to budgets rather than specially implemented projects. Capacities of ministries and effectiveness public systems will have significant bearing on effectiveness and impact of investments in agriculture. This public expenditure and institutional review of Ghana’s Ministry of Food and Agriculture offers insights on diagnosing limitations to and identifying strategies for improving the capacity of ministries to make effective use of human and financial resources. The review makes use a conceptual framework in which mission and functions, organizational capacity – a combination of structures, processes and resources –and organizational incentives interact to produce organizational performance. Indicative strategies are recommended that the ministry can use to generate discussions internally and developed a set a reforms that are owned. They key message is that to improve performance both capacity and incentives faced by organizations need to be addressed.agriculture, ministry, capacity, expenditure review, institutions,

Bacterial etiology of sexually transmitted infections at a STI clinic in Ghana; use of multiplex real time PCR

Background: Most sexually transmitted infection (STI) management efforts focus on the syndromic approach to diagnose and treat patients. However, most women with STIs have been shown to be entirely asymptomatic, or if symptoms exist, are often missed when either clinical or conventional bacteriologic diagnostic tools are employed.Methods: We assessed the performance of a multiplex real time PCR assay to describe other potential pathogens that could be missed by conventional bacteriological techniques in 200 women attending a routine STI clinic in Kumasi, Ghana.Results: Although a total 78.00% of the women were asymptomatic, 77.1% of them tested positive for at least one bacterial STI pathogen. Mycoplasma genitalium was the most commonly detectable pathogen present in 67.5% of all women. Of those testing positive, 25.0% had single infections, while 38.0% and 19.5% had double and triple infections respectively. Altogether, 86.54% and 90.91% of the symptomatic and asymptomatic women respectively tested positive for at least one pathogen (p<0.05). There were no significant associations (p<0.05) between the clinical manifestations of the symptomatic women and the pathogens detected in their samples.Conclusions: Our study confirmed the importance of complementing the syndromic approach to STI management with pathogen detection and most importantly recognise that STIs in women are asymptomatic and regular empirical testing even for both symptomatic and asymptomatic patients is critical for complete clinical treatment.Funding: EOD (Ellis Owusu-Dabo Research working group, KCCR)Keywords: Etiology, Syndromic, Sexually Transmitted Infections, Multiplex real time PC

Los altos precios de los alimentos: El ‘qué', ‘quién' y ‘cómo' de las acciones de política propuestas

"La complejidad de las causas de la actual crisis alimentaria y agrícola requiere de una respuesta integral. En vista de que es urgente prestar asistencia a las poblaciones y los países necesitados, la primera serie de acciones de política —un paquete de emergencia— consiste en varios pasos para generar un impacto inmediato: 1. Incrementar las acciones de emergencia y la ayuda humanitaria para incluir a las poblaciones que experimentan inseguridad alimentaria y a las que amenazan la legitimidad gubernamental; 2. Eliminar la prohibición y las restricciones a las exportaciones agrícolas; 3. Emprender programas que permitan rápidamente expandir la oferta alimentaria en áreas clave; y, 4. Modificar las políticas de los biocombustibles. Una segunda serie de acciones de política —un paquete de resiliencia socioeconómica— consiste en los siguientes pasos: 5. Proveer tranquilidad en los mercados mediante una regulación de los movimientos especulativos a través de instrumentos de mercado, reservas públicas y compartidas de granos, un mayor financiamiento para la importación de alimentos, y una ayuda alimentaria confiable; 6. Invertir en protección social; 7. Incrementar paulatinamente las inversiones para un crecimiento agrícola sostenido; y, 8. Concluir las negociaciones de la Ronda de Doha de la Organización Mundial del Comercio (OMC). La inversión en estas acciones requiere de recursos adicionales. Las instancias decisorias deberán considerar la movilización de recursos provenientes de cuatro fuentes: los países que se han beneficiado del auge de los commodities agrícolas; la comunidad de países donantes, tanto tradicionales como nuevos; impuestos proporcionales, directos o indirectos, y la reasignación del gasto público en los propios países afectados; y la movilización de los recursos financieros del sector privado, lo que incluye una ampliación en la cobertura de los servicios financieros para la agricultura. Debido a las diversas situaciones que enfrentan, los mismos países deben dirigir y apropiarse del diseño de los programas. La rendición de cuentas en cuanto a una implementación acertada también deberá recaer en los países. Al mismo tiempo, se necesita una nueva estructura internacional de gobernabilidad para la agricultura, la alimentación y la nutrición, a fin de implementar de forma eficaz las iniciativas descritas, especialmente los componentes relativos a los bienes públicos internacionales. También es necesaria la acción, tanto en el ámbito mundial como nacional, a través de los mecanismos existentes, iniciativas especiales muy bien coordinadas y posiblemente un fondo especial." from TextFood prices, Food supply, Food demand, Social protection, Agricultural research, Agricultural policy, Agricultural subsidies,

Machine learning methods for automatic segmentation of images of field-and glasshouse-based plants for high-throughput phenotyping

Image segmentation is a fundamental but critical step for achieving automated high- throughput phenotyping. While conventional segmentation methods perform well in homogenous environments, the performance decreases when used in more complex environments. This study aimed to develop a fast and robust neural-network-based segmentation tool to phenotype plants in both field and glasshouse environments in a high-throughput manner. Digital images of cowpea (from glasshouse) and wheat (from field) with different nutrient supplies across their full growth cycle were acquired. Image patches from 20 randomly selected images from the acquired dataset were transformed from their original RGB format to multiple color spaces. The pixels in the patches were annotated as foreground and background with a pixel having a feature vector of 24 color properties. A feature selection technique was applied to choose the sensitive features, which were used to train a multilayer perceptron network (MLP) and two other traditional machine learning models: support vector machines (SVMs) and random forest (RF). The performance of these models, together with two standard color-index segmentation techniques (excess green (ExG) and excess green–red (ExGR)), was compared. The proposed method outperformed the other methods in producing quality segmented images with over 98%-pixel classification accuracy. Regression models developed from the different segmentation methods to predict Soil Plant Analysis Development (SPAD) values of cowpea and wheat showed that images from the proposed MLP method produced models with high predictive power and accuracy comparably. This method will be an essential tool for the development of a data analysis pipeline for high-throughput plant phenotyping. The proposed technique is capable of learning from different environmental conditions, with a high level of robustness

Treatment choices for fevers in children under-five years in a rural Ghanaian district

<p>Abstract</p> <p>Background</p> <p>Health care demand studies help to examine the behaviour of individuals and households during illnesses. Few of existing health care demand studies examine the choice of treatment services for childhood illnesses. Besides, in their analyses, many of the existing studies compare alternative treatment options to a single option, usually self-medication. This study aims at examining the factors that influence the choices that caregivers of children under-five years make regarding treatment of fevers due to malaria and pneumonia in a rural setting. The study also examines how the choice of alternative treatment options compare with each other.</p> <p>Methods</p> <p>The study uses data from a 2006 household socio-economic survey and health and demographic surveillance covering caregivers of 529 children under-five years of age in the Dangme West District and applies a multinomial probit technique to model the choice of treatment services for fevers in under-fives in rural Ghana. Four health care options are considered: self-medication, over-the-counter providers, public providers and private providers.</p> <p>Results</p> <p>The findings indicate that longer travel, waiting and treatment times encourage people to use self-medication and over-the-counter providers compared to public and private providers. Caregivers with health insurance coverage also use care from public providers compared to over-the-counter or private providers. Caregivers with higher incomes use public and private providers over self-medication while higher treatment charges and longer times at public facilities encourage caregivers to resort to private providers. Besides, caregivers of female under-fives use self-care while caregivers of male under-fives use public providers instead of self-care, implying gender disparity in the choice of treatment.</p> <p>Conclusions</p> <p>The results of this study imply that efforts at curbing under-five mortality due to malaria and pneumonia need to take into account care-seeking behaviour of caregivers of under-fives as well as implementation of strategies.</p