16 research outputs found
A facile chemical conversion synthesis of Sb2S3 nanotubes and the visible light-driven photocatalytic activities
We report a simple chemical conversion and cation exchange technique to realize the synthesis of Sb2S3 nanotubes at a low temperature of 90°C. The successful chemical conversion from ZnS nanotubes to Sb2S3 ones benefits from the large difference in solubility between ZnS and Sb2S3. The as-grown Sb2S3 nanotubes have been transformed from a weak crystallization to a polycrystalline structure via successive annealing. In addition to the detailed structural, morphological, and optical investigation of the yielded Sb2S3 nanotubes before and after annealing, we have shown high photocatalytic activities of Sb2S3 nanotubes for methyl orange degradation under visible light irradiation. This approach offers an effective control of the composition and structure of Sb2S3 nanomaterials, facilitates the production at a relatively low reaction temperature without the need of organics, templates, or crystal seeds, and can be extended to the synthesis of hollow structures with various compositions and shapes for unique properties
Clinical Manifestations Associated with Neurocysticercosis: A Systematic Review
Neurocysticercosis is an infection of the brain with the flatworm Taenia solium which is normally transmitted between humans and pigs. Sometimes, humans can infect other humans and the larva of the parasite can go the brain, causing the disease neurocysticercosis. There has never been a systematic review of what clinical signs are found among people with neurocysticercosis. We conducted a thorough review of the literature to answer this question. We reviewed 1569 and 21 were of a sufficient quality to be included in the final analysis. Among neurocysticercosis patients who are seeking care in neurology clinics, about 79% have seizures/epilepsy, 38% severe headaches, 16% focal deficits and 12% signs of increased intracranial pressure. Several other symptoms were also reported in less than 10% of patients. People with neurocysticercosis who seek care in neurology clinics show a whole range of manifestations. Clinicians should be encouraged to consider neurocysticercosis in their differential diagnosis when a patient presented with one of the symptoms described in this review. This would ultimately improve the estimates of the frequency of symptoms associated with neurocysticercosis
Cross-Location Analysis of the Impact of Household Socioeconomic Status on Participation in Urban and Peri-Urban Agriculture in West Africa
This study explores the relation between household socioeconomic status (SES) and participation in urban and periurban agriculture (UPA) in three West African cities. We used a structured questionnaire to survey 700 randomly selected households: 250 in Kano, Nigeria, 250 in Bobo Dioulasso, Burkina Faso, and 200 in Sikasso, Mali. Multiple correspondence analysis was applied on household asset variables to create an index of assets which was used as a proxy for household SES. The results showed no significant differences in households’ rate of participation in UPA across socioeconomic groups. Participation in UPA was rather significantly (P < 0.001) and positively related to household size. Interestingly, the analysis revealed that field crop cultivation and gardening were more common among households in the low and medium SES groups while those in the high SES group were more likely to keep livestock
Contribution of draft cattle to rural livelihoods in a district of southeastern Uganda endemic for bovine parasitic diseases: an economic evaluation
BACKGROUND: A study was conducted in Tororo District in eastern Uganda to assess the socio-economic contribution of draft cattle to rural livelihoods. The aim of the study was to empirically quantify the economic value of draft cattle thus contributing to understanding the impact of endemic parasitic diseases of cattle on livestock productivity and subsequently household income, labor and food security. METHOD: A total of 205 draft cattle keeping households (n = 205) were randomly selected and structured household questionnaires were administered, focusing on work oxen use, productivity, inputs and outputs. The data obtained was analyzed using standard statistical methods and used to calculate the gross margin from the draft cattle enterprise. Secondary data were obtained from focus group discussions and key informant interviews and these were analyzed using Bayesian methods. RESULTS: The study showed that, apart from being labor saving, the use of animal traction is highly profitable with the gross margin per year from the use of draft cattle amounting to 245 United States dollars per work oxen owning household. The cash obtained from hiring out draft animals was equivalent to nearly a quarter of the average local household’s monetary receipts. It also revealed that endemic bovine parasitic diseases such as trypanosomiasis and tick-borne diseases reduced draft cattle output by 20.9 % and potential household income from the use of draft oxen by 32.2 %. CONCLUSION: The presence of endemic cattle diseases in rural Uganda is adversely affecting the productivity of draft cattle, which in turn affects household income, labor and ultimately food security. This study highlights the contribution of draft cattle to rural livelihoods, thus increasing the expected impact of cost-effective control strategies of endemic production limiting livestock diseases in Uganda
Managing neurocysticercosis: challenges and solutions
Yannick Fogoum Fogang, Abdoul Aziz Savadogo, Massaman Camara, Dènahin Hinnoutondji Toffa, Anna Basse, Adjaratou Djeynabou Sow, Mouhamadou Mansour Ndiaye Neurology Department, Fann Teaching Hospital, Cheikh Anta Diop University, Dakar, Senegal Abstract: Taenia solium neurocysticercosis (NCC) is a major cause of neurological morbidity in the world. Variability in the neuropathology and clinical presentation of NCC often make it difficult to diagnose and manage. Diagnosis of NCC can be challenging especially in endemic and resource-limited countries where laboratory and imaging techniques are often lacking. NCC management can also be challenging as current treatment options are limited and involve symptomatic agents, antiparasitic agents, or surgery. Although antiparasitic treatment probably reduces the number of active lesions and long-term seizure frequency, its efficacy is limited and strategies to improve treatment regimens are warranted. Treatment decisions should be individualized in relation to the type of NCC. Initial measures should focus on symptomatic management, with antiparasitic therapy only to be considered later on, when appropriate. Symptomatic treatment remains the cornerstone in NCC management which should not only focuses on epilepsy, but also on other manifestations that cause considerable burden (recurrent headaches, cognitive decline). Accurate patients' categorization, better antiparasitic regimens, and definition of new clinical outcomes for trials on NCC could improve management quality and prognosis of NCC. Prevention strategies targeting tapeworm carriers and infected pigs are yielding good results in local models. If local elimination of transmission is confirmed and replicated, this will open the door to cysticercosis eradication efforts worldwide. Keywords: neurocysticercosis, Taenia solium, epilepsy, headache, albendazole, praziquante
Adoption of eco-friendly soil-management practices by smallholder farmers in Shandong Province of China
Antimony sulphide, an absorber layer for solar cell application
Replacement of the toxic, expensive and scarce materials with nontoxic, cheap and earth-abundant one, in solar cell absorber layer, is immensely needed to realize the vision of green and sustainable energy. Two-micrometre-thin antimony sulphide film is considered to be adequate as an absorbing layer in solar cell applications. In this paper, we synthesize antimony sulphide thin films on glass substrate by physical vapour deposition technique, and the obtained films were then annealed at different temperatures (150–250 °C). The as-deposited and annealed samples were investigated for structural and optoelectronic properties using different characterization techniques. The X-ray diffraction analysis showed that the annealed samples were polycrystalline with Sb2S3 phase, while the as-deposited sample was amorphous in nature. The optical properties are measured via optical ellipsometric techniques. The measured absorbance of the film is adequately high, and every photon is found to be absorbed in visible and NIR range. The conductivity type of the films measured by hot-point probe technique is determined to be p-type. The optical band gap of the resulted samples was in the range (2.4–1.3 eV) for the as-deposited and annealed films
Influences of Electrode Potential on Mechanism of Oxygen Reduction Reaction on Pd-Skin/Pd3Fe(111) Electrocatalyst: Insights from DFT-Based Calculations
Palladium-Based Electrocatalysts for Oxygen Reduction Reaction
Fuel cells are clean energy devices that are expected to help address the energy and environmental problems in our society. Platinum-based nanomaterials are usually used as the electrocatalysts for both the anode (hydrogen oxidation) and cathode (oxygen reduction) reactions. The high cost and limited resources of this precious metal hinder the commercialization of fuel cells. Recent efforts have focused on the discovery of palladium-based electrocatalysts with little or no platinum for oxygen reduction reaction (ORR). This chapter overviews the recent progress of electrocatalysis of palladium-based materials including both extended surfaces and nanostructured ones for ORR. © Springer-Verlag London 2013.[Shao, M.] UTC Power, 195 Governor's Highway, South Windsor, CT, 06074, United State