581 research outputs found

    The Melbourne Shuffle: Improving Oblivious Storage in the Cloud

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    We present a simple, efficient, and secure data-oblivious randomized shuffle algorithm. This is the first secure data-oblivious shuffle that is not based on sorting. Our method can be used to improve previous oblivious storage solutions for network-based outsourcing of data

    Influence of Cereal-Legume Rotation on Striga Control and Maize Grain Yield in Farmers’ Fields in the Northern Guinea Savanna of Nigeria

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    On-farm trials were conducted in 2001, 2002, and 2003 in the northern Guinea savanna of Nigeria to evaluate integrated Striga hermonthica control measures under farmermanaged conditions. These included intercropping a Striga-resistant maize variety with cowpea for 3 years and also cropping this maize in rotation with legume trap crops - soybean and cowpea for 1-2 two years. Intercropping Striga-tolerant maize variety, Acr. 97TZL Comp. 1-W, with cowpea (Vigna unguiculata L.) consistently reduced Striga infestation in maize relative to continuously cropped sole maize over the threeyear period. Maize grain yield was lower in the intercrop than in the sole maize plot probably due to competition from cowpea. However, because of the high value of cowpea in the intercrop, crop value for this system was higher than sole cropped maize. Legume-maize rotation reduced Striga infestation by 35% after one year of legumes in the rotation and by 76% after two years of legumes in the rotation. Soybean was more effective in reducing Striga infestation and also gave higher maize grain yield than cowpea. The rotation of these two legumes with maize had clear advantage over continuously cropped maize. Farmers should therefore be encouraged to adopt the introduction of grain legumes into the cereal cropping systems of the Nigerian savanna

    Intensive cereal-legume–livestock systems in West African dry Savannas.

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    The dry savannas of West Africa are undergoing rapid transformation of agricultural practices owing to the rapid human and livestock population growth, increase in agricultural intensification and accelerated climate change which has increased the incidence and severity of diseases, pests and drought. The major constraints to agricultural production in the savanna include poor soil fertility, pests and diseases of crops and livestock, parasitic weeds such as Striga hermonthica, drought, and competition between crops and livestock for resources, Inadequate policies, weak institutional mechanisms, and poor linkages among farmers, and researchers prevent adoption of improved agricultural technologies that can combat these constraints. The risk of continuous cultivation on these poor and fragile soils is huge. Integrating crop and livestock production offers ways to increase production while protecting the environment. Over the years, research and development institutions have generated several agricultural technologies to alleviate the majority of the production constraints in the West African savannas. However, most development organizations use traditional extension methods that result in poor adoption of the improved technologies. The integration of crop and livestock production is particularly desirable in intensively farmed and densely populated areas with access to urban markets. Proper integration of these practices will diversify smallholder income and increase food security. Integrated genetic and natural resource management provides the keys improved eco-efficiency. This includes integrating pesticide use with cultural practices such as modified planting date and disease control; rotating/ intercropping cereals and legumes; use of pest resistant\tolerant cultivars to increase the effectiveness of pest control and reduce the need for pesticides; and improving soil fertility restoration/maintenance. Government and national institutions in West Africa are encouraged to scale-out these technologies to wider areas for increased benefit to farmers through the use of proven extension methods

    Cooperative governance and local economic development in selected small towns : a case study of the Western Cape Province, South Africa

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    CITATION: Kamara, R. D. 2021. Cooperative governance and local economic development in selected small towns : a case study of the Western Cape Province, South Africa. RUDN Journal of Public Administration, 8(4):405-422, doi:10.22363/2312-8313-2021-8-4-405-422.The original publication is available at http://journals.rudn.ruThis article reports on a study based on cooperative governance and Local Economic Development (LED) in selected small towns in the Western Cape Province. The dearth of an integrative institutional framework to promote collaborative participation negatively influences local municipalities’ ability to successfully manage LED cooperatively with relevant stakeholders. Promoting such inclusive representation and participation of all relevant stakeholders provides a viable and complementary alternative to the traditional bureaucratic governance mechanism. The study investigated the specific factors involved in designing and implementing cooperative governance for LED in selected, comparable municipalities in the Western Cape. Specifically, the study aims to determine the push and pull factors for the successful functioning of cooperative governance aimed at promoting LED in those municipalities. Data were collected through three data collection instruments, namely, document review, interviews, and focus group discussions. The document review is complemented by data from interviews and focus groups discussion. The study contributes to the body of knowledge on cooperative governance by identifying the specific cooperative governance factors, enabling the efficacy and governance of LED in small towns, aimed at positively influencing municipalities’ ability to successfully manage LED cooperatively with relevant stakeholders. An in-depth understanding of the relationship and dynamics of these variables helps to offer recommendations as to how to improve the management and responsiveness to socio-economic concerns within the municipalities through improved LED governance.http://journals.rudn.ru/public-administration/article/view/29649Publisher's versio

    Bringing the social into vaccination research: Community-led ethnography and trust-building in immunization programs in Sierra Leone

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    Background Vaccine hesitancy is a complex, contested social phenomenon and existing research highlights the multifaceted role of trust in strengthening vaccine confidence. However, understanding public engagement with vaccination through the lens of (mis)trust requires more contextual evidence on trust's qualitative determinants. This includes expanding the geographic focus beyond current studies' focus on High Income Countries. Furthermore, obstacles remain in effectively integrating social science findings in the design of vaccine deployment strategies, and in ensuring that those who implement interventions and are affected by them are directly involved in producing knowledge about vaccination challenges. Methods We piloted a community-led ethnographic approach, training Community Health Workers (CHWs) in Kambia District, Sierra Leone, in qualitative social science methods. Methods included participant observation, participatory power mapping and rumour tracking, focus group discussions and key stakeholder interviews. CHWs, with the support of public health officials and professional social scientists, conducted research on vaccination challenges, analysed data, tested new community engagement strategies based on their findings and elicited local perspectives on these approaches. Results Our findings on vaccine confidence in five border communities highlighted three key themes: the impact of prior experiences with the health system on (mis)trust; relevance of livelihood strategies and power dynamics for vaccine uptake and access; and the contextual nature of knowledge around vaccines. Across these themes, we show how expressions of trust centered on social proximity, reliability and respect and the role of structural issues affecting both vaccine access and confidence. The pilot also highlighted the value and practical challenges to meaningfully co-designed research. Conclusion There is scope for broader application of a community-led ethnographic approach will help redesign programming that is responsive to local knowledge and experience. Involving communities and low-cadre service providers in generating knowledge and solutions can strengthen relationships and sustain dialogue to bolster vaccine confidence

    Performance of semideterminate and indeterminate cowpeas relaycropped into maize in Northeast Nigeria

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    Field trials were conducted in 2005 and 2006 in Tilla (northern Guinea savanna) and Sabon-Gari (Sudan savanna) in northeast Nigeria to determine the performance of two improved cowpea varieties when relay-intercropped with early and late maize, 6 and 8 weeks after planting the maize. Grain yield, number of branches and number of pods per plant were higher for the variety IT89KD-288 than for IT97K-499-35, whether planted sole or relay-intercropped with maize. Grain yield was lower for IT97K-499-35 than for IT89KD-288 when relay-intercropped with maize irrespective of the maturity period of the companion maize crop. This may be due to the indeterminate growth habit and shade tolerance of IT89KD-288 which allowed a higher pod load than IT97K-499-35. However, relay-intercropping with early maize gave higher yield than relay-intercropping into late maize. Also relay-intercropping at 6 weeks after planting maize (WAP) gave a higher yield than relay-intercropping at 8 WAP. This therefore, suggests that introducing cowpea into short statured early maize may mean less competition for light and soil resources compared to taller late maize. Also introducing the cowpea earlier may allow the crop to make full use of soil moisture during the cropping season

    Studi In Vitro Potensi Kurkuminoid (Curcuma Domestica Vahl) dan Senyawa-senyawanya terhadap Superoksidadismutase dan pada Proses Peroksidasi Lipid Sel Monosit.

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    Tujuan penelitian adalah untuk mengetahui apakah masing-masing sampel ( kurkuminoid,kurkumin, desmetoksikurkumin dan bisdesmetoksikurkumin ) dengan dosis sama (3,68 ug/50ul)yang diisolasi dan dimurnikan dari rimpang kunyit (Curcuma domestica Vahl) memiliki efekterhadap aktivitas superoksidadismutase dan terhadap proses peroksidasi lipid secara in vitro.Subjek penelitian menggunakan sel monosit yang diisolasi dari darah pria dewasa normaldengan metode Boyum.Masing-masing sampel dibagi ke dalam dua grup, grup (a) dilarutkan dalam dimetilsulfoksida(DMSO), dan grup (b) dilarutkan dalam air suling. Kedua grup sampel tersebut diuji terhadapaktivitas superoksidadismutase, dilakukan dengan metode Murakami, dan juga diuji terhadapproses peroksidasi lipid sel monosit dilakukan dengan metode TBARS.Hasil penelitian dari kedua grup sampel, memiliki efek meningkatkan aktivitassuperoksidadismutase secara bermakna (p< 0,05), demikian pula dapat menghambat terhadapproses peroksidasi lipid, yang ditunjukan dengan penurunan kadar malondialdehid secarabermakna (p< 0,05).Sampel grup (a) memiliki kekuatan lebih besar terhadap peningkatan aktivitas superoksidadismutasejika dibandingkan dengan sampel grup (b), khususnya terlihat pada kurkuminoidaktivitasnya hampir menyamai α-tokoferol.Kurkumin baik dari grup (a) maupun dari grup (b) memiliki aktivitas yang lebih besar terhadappenghambatan proses peroksidasi lipid dibandingkan dengan kurkuminoid, desmetoksikurkumindan bisdesmetoksi-kurkumin. Bahkan lebih kuat dari α-tokoferol

    The Relation of Mitochondrial DNA Mutation with Mitochondrial Diseaseas in Coding Region

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    AbstractMitochondrial disorders are recognized in several metabolic and degenerative diseases, aging and cancer. Mitochondrial functional deficiency maybe caused by a decrease in the function of complex respiratory enzymes that can inhibit the oxidative phosphorylation chain (OXPHOS) for synthesis of ATP. Based on data MITOMAP in 2013, there are 211 of 466 mutations that have been reported in coding region. The largest number of mutation located on MT-COI region that have 34mutations. In particular, mutations in a subunit of COX have been described associate with various clinical phenotypes. Deficiency of COX is one of disorder that often leads to mitochondrial disease. Based on the database, the dominant disease on subunit of COI is dominated by prostate cancer. Moreover, the highest probability of mutation to the size of gene located on MT-NDI with 2.83%. OXPHOS deficiency which is caused by DNA mitochondrial mutation, mostly appears on subunit ND1. The dominant phenotype on subunit of NDI is Leber's hereditary optic neuropathy (LHON) diseases. This study has revealed that mutations in mitochondrial DNA were not only associated with predisposition to neuromuscular diseases but also to cancer and optical interference

    Structured Encryption and Leakage Suppression

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    Structured encryption (STE) schemes encrypt data structures in such a way that they can be privately queried. One aspect of STE that is still poorly understood is its leakage. In this work, we describe a general framework to design STE schemes that do not leak the query/search pattern (i.e., if and when a query was previously made). Our framework consists of two compilers. The first can be used to make any dynamic STE scheme rebuildable in the sense that the encrypted structures it produces can be rebuilt efficiently using only O(1) client storage. The second transforms any rebuildable scheme that leaks the query/search pattern into a new scheme that does not. Our second compiler is a generalization of Goldreich and Ostrovsky\u27s square root oblivious RAM (ORAM) solution but does not make use of black-box ORAM simulation. We show that our framework produces STE schemes with query complexity that is asymptotically better than ORAM simulation in certain (natural) settings and comparable to special-purpose oblivious data structures. We use our framework to design a new STE scheme that is ``almost zero-leakage in the sense that it reveals an, intuitively-speaking, small amount of information. We also show how the scheme can be used to achieve zero-leakage queries when one can tolerate a probabilistic guarantee of correctness. This construction results from applying our compilers to a new STE scheme we design called the piggyback scheme. This scheme is a general-purpose STE construction (in the sense that it can encrypt any data structure) that leaks the search/query pattern but hides the response length on non-repeating queries
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