1,616 research outputs found
Use of Electrically Heated Metal Catalytic Converter in Cold Starting To Reduce Automotive Emissions
The environmental degradation all over the world has led the researchers to work towards the development of Low Emission Vehicle (LEV) and Ultra Low Emission Vehicle (ULEV). Automobile vehicles emit substantial quantities of hydrocarbons (HC), carbon monoxide (CO) and particulate matter. These pollutants have significant adverse health effects and deteriorate environmental quality. To address the serious pollution problems posed by vehicles, growing number of countries worldwide? Catalytic converters have implemented that in motor vehicle pollution control programs aimed substantially reducing harmful emissions from spark ignited vehicles. Catalytic exhaust controls have been developed as a result of these regulations and are generally recognized to be the most costâeffective way to meet stringent emission standards. The catalytic converter does a great job at reducing the pollution, but it can still be improved substantially. One of its biggest shortcomings is that it only works at a fairly high temperature. When car start at cold, the catalytic converter does almost nothing to reduce the pollution from exhaust. Preheating the catalytic converter is a good way to reduce emissions. The easiest way to preheat the converter is to use electric resistance heaters. The electrical systems on most cars provide enough energy or power to heat the catalytic converter fast enough. So, in this research the main converter remains its usual position, whereas the heated catalyst is placed close to the exhaust manifold. The EHMC quickly reaches high temperature levels due to the heat supply from external source, sensible heat of the exhaust and the heat generated by the exothermic oxidation. This in turn helps the faster light off of the main converter
Illiteracy is Insecurity: Education, Technology and Disability in South Africa
Abstract: This treatise argues that illiteracy is insecurity and, in South Africa, education has eluded the majority of disabled people. A technology divide is intensifying the abledisabled divide that has always existed in South Africa, thus creating a "cartel of satraps" that plunges the disabled into marginalization
Costs analysis of a population level rabies control programme in Tamil Nadu, India
The study aimed to determine costs to the state government of implementing different interventions for controlling rabies among the entire human and animal populations of Tamil Nadu. This built upon an earlier assessment of Tamil Naduâs efforts to control rabies. Anti-rabies vaccines were made available at all health facilities. Costs were estimated for five different combinations of animal and human interventions using an activity-based costing approach from the provider perspective. Disease and population data were sourced from the state surveillance data, human census and livestock census. Program costs were extrapolated from official documents. All capital costs were depreciated to estimate annualized costs. All costs were inflated to 2012 Rupees. Sensitivity analysis was conducted across all major cost centres to assess their relative impact on program costs. It was found that the annual costs of providing Anti-rabies vaccine alone and in combination with Immunoglobulins was \$0.7 million (Rs 36 million) and \$2.2 million (Rs 119 million), respectively. For animal sector interventions, the annualised costs of rolling out surgical sterilisation-immunization, injectable immunization and oral immunizations were estimated to be \$ 44 million (Rs 2,350 million), \$23 million (Rs 1,230 million) and \$ 11 million (Rs 590 million), respectively. Dog bite incidence, health systems coverage and cost of rabies biologicals were found to be important drivers of costs for human interventions. For the animal sector interventions, the size of dog catching team, dog population and vaccine costs were found to be driving the costs. Rabies control in Tamil Nadu seems a costly proposition the way it is currently structured. Policy makers in Tamil Nadu and other similar settings should consider the long-term financial sustainability before embarking upon a state or nation-wide rabies control programme
Aspects ĂpidĂ©miologiques et Cliniques des Cervicalgies non Traumatiques en Consultation de Rhumatologie Ă BouakĂ©
Objectif : Etudier les caractĂ©ristiques Ă©pidĂ©miologiques et diagnostiques des cervicalgies non traumatiques (CNT) chez une population noire dâAfrique sub-saharienne. Patients et mĂ©thodes : Etude rĂ©trospective descriptive sur une pĂ©riode de six ans, de Janvier 2014 Ă DĂ©cembre 2019 portant sur les patients vus pour une CNT en consultation de rhumatologie Ă BouakĂ© en CĂŽte dâ Ivoire. RĂ©sultats : Sur 4036 patients vus pour une affection rhumatologique, 130 avaient une CNT soit une frĂ©quence de 3,2%. LâĂąge moyen des patients Ă©tait de 54,03 ± 13,71 ans et le sex ratio de 0,8. Le groupe dâĂąge de 40 Ă 70 ans reprĂ©sentait 74,6 % des patients (97 cas). Les patients consultaient surtout pour une forte douleur Ă dĂ©but progressif (56,2%), dâĂ©volution chronique (63,9%), et une monoparĂ©sie brachiale Ă©tait observĂ©e dans quatre cas (3,1%). Il sâagissait surtout dâune cervicalgie isolĂ©e (63,1%), parfois associĂ©e Ă une nĂ©vralgie cervico-brachiale (9,2%), Ă une rachialgie dorsolombaire (18,5%) ou Ă une arthralgie pĂ©riphĂ©rique (9,2%). La radiographie standard (94,6%) Ă©tait lâimagerie la plus prescrite. Les diagnostics retenus Ă©taient la cervicalgie commune (87,7%), la polyarthrite rhumatoĂŻde (4,6%), le mal de Pott (3,1%), une mĂ©tastase de cancer de la prostate (1,5%), et le myĂ©lome multiple (3,1%). Soixante-douze patients (55,4%) avaient entrepris une automĂ©dication avant la consultation avec des anti-inflammatoires dans 43,1% des cas et des antibiotiques dans 4,2%. Conclusion : La CNT nâest pas rare en consultation rhumatologique Ă BouakĂ©. Elle touche surtout les patients entre 40 et 70 ans et les femmes sont les plus concernĂ©es. La cervicalgie commune est le diagnostic le plus frĂ©quent.
Objective: To study the epidemiological and diagnostic features of non-traumatic neck pain in a black sub-Saharan African population. Patients and methods: Retrospective descriptive study over a six-year period, from January 2014 to December 2019 covering patients seen for non-traumatic neck pain in rheumatology consultation in Bouaké, CÎte d' Ivoire. Results: Of 4036 patients seen for a rheumatological condition, 130 had non-traumatic neck pain, a frequency of 3.2%. The mean age of patients was 54.03 ± 13.71 years, and the sex ratio was 0.8. The 40-70 age group accounted for 74.6% of patients (97 cases). Patients mainly consulted for severe pain with progressive onset (56.2%), chronic evolution (63.9%), and brachial monoparesis was observed in four cases (3.1%). The pain was mainly isolated cervicalgia (63.1%), sometimes associated with cervicobrachial neuralgia (9.2%), dorsolumbar spinalgia (18.5%) or peripheral arthralgia (9.2%). Standard radiography (94.6%) was the most frequently prescribed imaging technique. The most common diagnoses were common neck pain (87.7%), rheumatoid arthritis (4.6%), Pott's disease (3.1%), prostatic metastasis (1.5%), and multiple myeloma (3.1%). Seventy-two patients (55.4%) had undertaken self-medication prior to consultation, with non-steroidal anti-inflammatory drugs in 43.1% of cases and antibiotics in 4.2%. Conclusion: Non-traumatic neck pain is not uncommon in rheumatology consultations in Bouaké. It mainly affects patients between 40 and 70 years of age, and women are most affected. Common cervicalgia is the most frequent diagnosis
Aspects ĂpidĂ©miologiques et Cliniques des Cervicalgies non Traumatiques en Consultation de Rhumatologie Ă BouakĂ©
Objectif : Etudier les caractĂ©ristiques Ă©pidĂ©miologiques et diagnostiques des cervicalgies non traumatiques (CNT) chez une population noire dâAfrique sub-saharienne. Patients et mĂ©thodes : Etude rĂ©trospective descriptive sur une pĂ©riode de six ans, de Janvier 2014 Ă DĂ©cembre 2019 portant sur les patients vus pour une CNT en consultation de rhumatologie Ă BouakĂ© en CĂŽte dâ Ivoire. RĂ©sultats : Sur 4036 patients vus pour une affection rhumatologique, 130 avaient une CNT soit une frĂ©quence de 3,2%. LâĂąge moyen des patients Ă©tait de 54,03 ± 13,71 ans et le sex ratio de 0,8. Le groupe dâĂąge de 40 Ă 70 ans reprĂ©sentait 74,6 % des patients (97 cas). Les patients consultaient surtout pour une forte douleur Ă dĂ©but progressif (56,2%), dâĂ©volution chronique (63,9%), et une monoparĂ©sie brachiale Ă©tait observĂ©e dans quatre cas (3,1%). Il sâagissait surtout dâune cervicalgie isolĂ©e (63,1%), parfois associĂ©e Ă une nĂ©vralgie cervico-brachiale (9,2%), Ă une rachialgie dorsolombaire (18,5%) ou Ă une arthralgie pĂ©riphĂ©rique (9,2%). La radiographie standard (94,6%) Ă©tait lâimagerie la plus prescrite. Les diagnostics retenus Ă©taient la cervicalgie commune (87,7%), la polyarthrite rhumatoĂŻde (4,6%), le mal de Pott (3,1%), une mĂ©tastase de cancer de la prostate (1,5%), et le myĂ©lome multiple (3,1%). Soixante-douze patients (55,4%) avaient entrepris une automĂ©dication avant la consultation avec des anti-inflammatoires dans 43,1% des cas et des antibiotiques dans 4,2%. Conclusion : La CNT nâest pas rare en consultation rhumatologique Ă BouakĂ©. Elle touche surtout les patients entre 40 et 70 ans et les femmes sont les plus concernĂ©es. La cervicalgie commune est le diagnostic le plus frĂ©quent.
Objective: To study the epidemiological and diagnostic features of non-traumatic neck pain in a black sub-Saharan African population. Patients and methods: Retrospective descriptive study over a six-year period, from January 2014 to December 2019 covering patients seen for non-traumatic neck pain in rheumatology consultation in Bouaké, CÎte d' Ivoire. Results: Of 4036 patients seen for a rheumatological condition, 130 had non-traumatic neck pain, a frequency of 3.2%. The mean age of patients was 54.03 ± 13.71 years, and the sex ratio was 0.8. The 40-70 age group accounted for 74.6% of patients (97 cases). Patients mainly consulted for severe pain with progressive onset (56.2%), chronic evolution (63.9%), and brachial monoparesis was observed in four cases (3.1%). The pain was mainly isolated cervicalgia (63.1%), sometimes associated with cervicobrachial neuralgia (9.2%), dorsolumbar spinalgia (18.5%) or peripheral arthralgia (9.2%). Standard radiography (94.6%) was the most frequently prescribed imaging technique. The most common diagnoses were common neck pain (87.7%), rheumatoid arthritis (4.6%), Pott's disease (3.1%), prostatic metastasis (1.5%), and multiple myeloma (3.1%). Seventy-two patients (55.4%) had undertaken self-medication prior to consultation, with non-steroidal anti-inflammatory drugs in 43.1% of cases and antibiotics in 4.2%. Conclusion: Non-traumatic neck pain is not uncommon in rheumatology consultations in Bouaké. It mainly affects patients between 40 and 70 years of age, and women are most affected. Common cervicalgia is the most frequent diagnosis
A random cell motility gradient downstream of FGF controls elongation of amniote embryos
Vertebrate embryos are characterized by an elongated antero-posterior (AP) body axis, which forms by progressive cell deposition from a posterior growth zone in the embryo. Here, we used tissue ablation in the chicken embryo to demonstrate that the caudal presomitic mesoderm (PSM) has a key role in axis elongation. Using time-lapse microscopy, we analysed the movements of fluorescently labelled cells in the PSM during embryo elongation, which revealed a clear posterior-to-anterior gradient of cell motility and directionality in the PSM. We tracked the movement of the PSM extracellular matrix in parallel with the labelled cells and subtracted the extracellular matrix movement from the global motion of cells. After subtraction, cell motility remained graded but lacked directionality, indicating that the posterior cell movements associated with axis elongation in the PSM are not intrinsic but reflect tissue deformation. The gradient of cell motion along the PSM parallels the fibroblast growth factor (FGF)/mitogen-activated protein kinase (MAPK) gradient1, which has been implicated in the control of cell motility in this tissue2. Both FGF signalling gain- and loss-of-function experiments lead to disruption of the motility gradient and a slowing down of axis elongation. Furthermore, embryos treated with cell movement inhibitors (blebbistatin or RhoK inhibitor), but not cell cycle inhibitors, show a slower axis elongation rate. We propose that the gradient of random cell motility downstream of FGF signalling in the PSM controls posterior elongation in the amniote embryo. Our data indicate that tissue elongation is an emergent property that arises from the collective regulation of graded, random cell motion rather than by the regulation of directionality of individual cellular movements
Factors Affecting Trypanosome Maturation in Tsetse Flies
Trypanosoma brucei brucei infections which establish successfully in the tsetse fly midgut may subsequently mature into mammalian infective trypanosomes in the salivary glands. This maturation is not automatic and the control of these events is complex. Utilising direct in vivo feeding experiments, we report maturation of T. b. brucei infections in tsetse is regulated by antioxidants as well as environmental stimuli. Dissection of the maturation process provides opportunities to develop transmission blocking vaccines for trypanosomiasis. The present work suggests L-cysteine and/or nitric oxide are necessary for the differentiation of trypanosome midgut infections in tsetse
Genomic signatures of population decline in the malaria mosquito Anopheles gambiae
Population genomic features such as nucleotide diversity and linkage disequilibrium are expected to be strongly shaped by changes in population size, and might therefore be useful for monitoring the success of a control campaign. In the Kilifi district of Kenya, there has been a marked decline in the abundance of the malaria vector Anopheles gambiae subsequent to the rollout of insecticide-treated bed nets. To investigate whether this decline left a detectable population genomic signature, simulations were performed to compare the effect of population crashes on nucleotide diversity, Tajima's D, and linkage disequilibrium (as measured by the population recombination parameter Ï). Linkage disequilibrium and Ï were estimated for An. gambiae from Kilifi, and compared them to values for Anopheles arabiensis and Anopheles merus at the same location, and for An. gambiae in a location 200 km from Kilifi. In the first simulations Ï changed more rapidly after a population crash than the other statistics, and therefore is a more sensitive indicator of recent population decline. In the empirical data, linkage disequilibrium extends 100-1000 times further, and Ï is 100-1000 times smaller, for the Kilifi population of An. gambiae than for any of the other populations. There were also significant runs of homozygosity in many of the individual An. gambiae mosquitoes from Kilifi. These results support the hypothesis that the recent decline in An. gambiae was driven by the rollout of bed nets. Measuring population genomic parameters in a small sample of individuals before, during and after vector or pest control may be a valuable method of tracking the effectiveness of interventions
Smoking in asthma is associated with elevated levels of corticosteroid resistant sputum cytokinesâan exploratory study
<p>Background: Current cigarette smoking is associated with reduced acute responses to corticosteroids and worse clinical outcomes in stable chronic asthma. The mechanism by which current smoking promotes this altered behavior is currently unclear. Whilst cytokines can induce corticosteroid insensitivity in-vitro, how current and former smoking affects airway cytokine concentrations and their responses to oral corticosteroids in stable chronic asthma is unclear.</p>
<p>Objectives: To examine blood and sputum cytokine concentrations in never, ex and current smokers with asthma before and after oral corticosteroids.</p>
<p>Methods: Exploratory study utilizing two weeks of oral dexamethasone (equivalent to 40 mg/day prednisolone) in 22 current, 21 never and 10 ex-smokers with asthma. Induced sputum supernatant and plasma was obtained before and after oral dexamethasone. 25 cytokines were measured by multiplex microbead system (Invitrogen, UK) on a Luminex platform.</p>
<p>Results: Smokers with asthma had elevated sputum cytokine interleukin (IL) -6, -7, and -12 concentrations compared to never smokers with asthma. Few sputum cytokine concentrations changed in response to dexamethasone IL-17 and IFNα increased in smokers, CCL4 increased in never smokers and CCL5 and CXCL10 reduced in ex-smokers with asthma. Ex-smokers with asthma appeared to have evidence of an ongoing corticosteroid resistant elevation of cytokines despite smoking cessation. Several plasma cytokines were lower in smokers wi</p>
<p>Conclusion: Cigarette smoking in asthma is associated with a corticosteroid insensitive increase in multiple airway cytokines. Distinct airway cytokine profiles are present in current smokers and never smokers with asthma and could provide an explanatory mechanism for the altered clinical behavior observed in smokers with asthma.</p>
recount3: summaries and queries for large-scale RNA-seq expression and splicing
We present recount3, a resource consisting of over 750,000 publicly available human and mouse RNA sequencing (RNA-seq) samples uniformly processed by our new Monorail analysis pipeline. To facilitate access to the data, we provide the recount3 and snapcount R/Bioconductor packages as well as complementary web resources. Using these tools, data can be downloaded as study-level summaries or queried for specific exon-exon junctions, genes, samples, or other features. Monorail can be used to process local and/or private data, allowing results to be directly compared to any study in recount3. Taken together, our tools help biologists maximize the utility of publicly available RNA-seq data, especially to improve their understanding of newly collected data. recount3 is available from http://rna.recount.bio
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