146 research outputs found

    Energy-efficient Vehicle Body Design for the Shell-Eco Marathon Competition

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    This article presents relevant information regarding the design process of the body of an energyefficient vehicle used by the students of Automotive Engineering Department, Universidad del Azuay for participation in the Shell-Eco Marathon of the Americas competition. The objective was to design a single-seater vehicle that is capable of travelling several kilometers with the least possible energy consumption; thus, a computational study CFD of the aerodynamic performance of the vehicle was conducted. This study showed the need to adjust the initial design proposal, decreasing its drag coefficient from 0.43 to 0.32. The body will be built using fiberglass and acrylic for the windows as they are light materials that are easy to mold, reducing the mass of the vehicle and its manufacturing cost. The single-seater car body not only presents the necessary safety to protect the driver from external agents but also provides the visibility needed to drive on the track. In this way, a single-seater vehicle that can participate in the competition, complying with its regulations and requirements, is presented. Keywords: aerodynamics, drag, coefficient, energy, one-seater vehicle. Resumen En el presente documento se muestra información relevante respecto al proceso de diseño de la carrocería para un vehículo eficiente energéticamente, con motivo de la participación de los estudiantes de la carrera de ingeniería automotriz de la Universidad del Azuay en la competencia Shell – Eco marathon de las Américas. El objetivo es diseñar un vehículo monoplaza que recorra la mayor cantidad de kilómetros con el menor consumo de energía posible, para ello se realizó el estudio computacional CFD del desempeño aerodinámico del vehículo; a través del cual se evidenció la necesidad de ajustar la propuesta de diseño inicial, disminuyendo su coeficiente de arrastre de 0.43 a 0.32. La carrocería se construirá utilizando fibra de vidrio y acrílico para las ventanas, debido a que son materiales ligeros y presentan facilidad de moldeo, disminuyendo la masa del vehículo y también su costo de manufactura. La forma de la carrocería es monoplaza y presenta la seguridad necesaria para proteger al piloto de agentes externos, así como también brinda la visibilidad necesaria para poder conducirlo por la pista. De esta manera se presenta un vehículo monoplaza que puede participar en la competencia cumpliendo con la reglamentación y exigencias de la misma. Palabras Clave: aerodinámica, arrastre, coeficiente, energía, monoplaza

    Risk Factors for Acquired Rifamycin and Isoniazid resistance: A systematic review and meta-analysis

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    BACKGROUND: Studies looking at acquired drug resistance (ADR) are diverse with respect to geographical distribution, HIV co-infection rates, retreatment status and programmatic factors such as regimens administered and directly observed therapy. Our objective was to examine and consolidate evidence from clinical studies of the multifactorial aetiology of acquired rifamycin and/or isoniazid resistance within the scope of a single systematic review. This is important to inform policy and identify key areas for further studies. METHODS: Case-control and cohort studies and randomised controlled trials that reported ADR as an outcome during antitubercular treatment regimens including a rifamycin and examined the association of at least 1 risk factor were included. Post hoc, we carried out random effects Mantel-Haenszel weighted meta-analyses of the impact of 2 key risk factors 1) HIV and 2) baseline drug resistance on the binary outcome of ADR. Heterogeneity was assessed used I 2 statistic. As a secondary outcome, we calculated median cumulative incidence of ADR, weighted by the sample size of the studies. RESULTS: Meta-analysis of 15 studies showed increased risk of ADR with baseline mono- or polyresistance (RR 4.85 95% CI 3.26 to 7.23, heterogeneity I 2 58%, 95% CI 26 to 76%). Meta-analysis of 8 studies showed that HIV co-infection was associated with increased risk of ADR (RR 3.02, 95% CI 1.28 to 7.11); there was considerable heterogeneity amongst these studies (I 2 81%, 95% CI 64 to 90%). Non-adherence, extrapulmonary/disseminated disease and advanced immunosuppression in HIV co-infection were other risk factors noted. The weighted median cumulative incidence of acquired multi drug resistance calculated in 24 studies (assuming whole cohort as denominator, regardless of follow up DST) was 0.1% (5 th to 95 th percentile 0.07 to 3.2%). CONCLUSION: Baseline drug resistance and HIV co-infection were significant risk factors for ADR. There was a trend of positive association with non-adherence which is likely to contribute to the outcome of ADR. The multifactorial aetiology of ADR in a programmatic setting should be further evaluated via appropriately designed studies

    Simultaneous High-performance Liquid Chromatography-tandem Mass Spectrometry (HPLC-MS-MS) Analysis of Cyanide and Thiocyanate from Swine Plasma

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    An analytical procedure for the simultaneous determination of cyanide and thiocyanate in swine plasma was developed and validated. Cyanide and thiocyanate were simultaneously analyzed by high-performance liquid chromatography tandem mass spectrometry in negative ionization mode after rapid and simple sample preparation. Isotopically labeled internal standards, Na13C15N and NaS13C15N, were mixed with swine plasma (spiked and nonspiked), proteins were precipitated with acetone, the samples were centrifuged, and the supernatant was removed and dried. The dried samples were reconstituted in 10 mM ammonium formate. Cyanide was reacted with naphthalene-2,3-dicarboxaldehyde and taurine to form N-substituted 1-cyano[f]benzoisoindole, while thiocyanate was chemically modified with monobromobimane to form an SCN-bimane product. The method produced dynamic ranges of 0.1–50 and 0.2–50 μM for cyanide and thiocyanate, respectively, with limits of detection of 10 nM for cyanide and 50 nM for thiocyanate. For quality control standards, the precision, as measured by percent relative standard deviation, was below 8 %, and the accuracy was within ±10 % of the nominal concentration. Following validation, the analytical procedure successfully detected cyanide and thiocyanate simultaneously from the plasma of cyanide-exposed swine

    Acciones solidarias con los damnificados del terremoto Ecuador – 2016

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    On July 19, 2016, the University of Azuay approves its project called "SOLIDARITY ACTIONS WITH THE DAMNIFIED PEOPLE OF ECUADOR EARTHQUAKE - 2016" which aims to improve the situation of the victims, from the potential of the academy, working from areas such as: culture, economic reactivation, innovation, alternatives for access to decent housing, internal and external communication between groups hosted in camps. These actions are proposed through intervention projects, establishing direct contact with the Samán Camp, located in the Canoa parish, San Vicente canton, in Manabí, shelter coordinated by the INTI Corporation. The proposed methodology proposes that each academic unit present to its Linking Coordination a project framed in the objectives of the "Solidarity Actions T-2016" Program, once these proposals were agreed with the academic boards, the University facilitated the transfer of equipment to the site for the survey the base information, execution of scheduled activities and delivery of results. Each of the projects had the participation of between 2 to 7 teachers and between 15 and 60 students, who in the framework of chairs or internships developed their projects. Today, four projects are underway: Internal, external communication and brand generation. Training in automotive maintenance. Design and manufacture of prototypes in bamboo cane. Housing projects and community equipment, in Canoa-Manabí.El 19 de julio de 2016, la Universidad del Azuay aprueba su proyecto denominado “ACCIONES SOLIDARIAS CON LOS DAMNIFICADOS DEL TERREMOTO ECUADOR – 2016” que plantea como fin la mejora de la situación de los damnificados, desde las potencialidades con las que cuenta la academia, trabajando desde áreas como: cultura, reactivación económica, innovación, alternativas para el acceso a la vivienda digna, comunicación interna y externa entre los grupos acogidos en campamentos. Estas acciones son propuestas a través de proyectos de intervención, estableciendo contacto directo con el Campamento Samán, ubicado en la parroquia Canoa, cantón San Vicente, en Manabí, albergue coordinado por la Corporación INTI. La metodología propuesta plantea que cada unidad académica presente a su Coordinación de vinculación un proyecto enmarcado en los objetivos del Programa “Acciones Solidarias T-2016”, una vez que estas propuestas fueron consensuadas con las juntas académicas, la Universidad facilitó el traslado de equipos al sitio para el levantamiento la información base, realización de actividades programadas y entrega de resultados. Cada uno de los proyectos contó con la participación de entre 2 a 7 docentes y entre 15 a 60 estudiantes, que en el marco de cátedras o pasantías desarrollaron sus proyectos. Hoy se tiene en marcha cuatro proyectos: Comunicación interna, externa y generación de marca. Capacitación en mantenimiento automotriz. Diseño y fabricación de prototipos en caña guadua. Proyectos de vivienda y equipamiento comunitario, en Canoa-Manabí

    Simultaneous Determination of Cyanide and Thiocyanate in Plasma by Chemical Ionization Gas Chromatography Mass-spectrometry (CI-GC-MS)

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    An analytical method utilizing chemical ionization gas chromatography-mass spectrometry was developed for the simultaneous determination of cyanide and thiocyanate in plasma. Sample preparation for this analysis required essentially one-step by combining the reaction of cyanide and thiocyanate with pentafluorobenzyl bromide and simultaneous extraction of the product into ethyl acetate facilitated by a phase-transfer catalyst, tetrabutylammonium sulfate. The limits of detection for cyanide and thiocyanate were 1 μM and 50 nM, respectively. The linear dynamic range was from 10 μM to 20 mM for cyanide and from 500 nM to 200 μM for thiocyanate with correlation coefficients higher than 0.999 for both cyanide and thiocyanate. The precision, as measured by %RSD, was below 9 %, and the accuracy was within 15 % of the nominal concentration for all quality control standards analyzed. The gross recoveries of cyanide and thiocyanate from plasma were over 90 %. Using this method, the toxicokinetic behavior of cyanide and thiocyanate in swine plasma was assessed following cyanide exposure

    Modelling Cognitive Decline in the Hypertension in the Very Elderly Trial [HYVET] and Proposed Risk Tables for Population Use

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    Although, on average, cognition declines with age, cognition in older adults is a dynamic process. Hypertension is associated with greater decline in cognition with age, but whether treatment of hypertension affects this is uncertain. Here, we modelled dynamics of cognition in relation to the treatment of hypertension, to see if treatment effects might better be discerned by a model that included baseline measures of cognition and consequent mortalityThis is a secondary analysis of the Hypertension in the Very Elderly Trial (HYVET), a double blind, placebo controlled trial of indapamide, with or without perindopril, in people aged 80+ years at enrollment. Cognitive states were defined in relation to errors on the Mini-Mental State Examination, with more errors signifying worse cognition. Change in cognitive state was evaluated using a dynamic model of cognitive transition. In the model, the probabilities of transitions between cognitive states is represented by a Poisson distribution, with the Poisson mean dependent on the baseline cognitive state. The dynamic model of cognitive transition was good (R(2) = 0.74) both for those on placebo and (0.86) for those on active treatment. The probability of maintaining cognitive function, based on baseline function, was slightly higher in the actively treated group (e.g., for those with the fewest baseline errors, the chance of staying in that state was 63% for those on treatment, compared with 60% for those on placebo). Outcomes at two and four years could be predicted based on the initial state and treatment.A dynamic model of cognition that allows all outcomes (cognitive worsening, stability improvement or death) to be categorized simultaneously detected small but consistent differences between treatment and control groups (in favour of treatment) amongst very elderly people treated for hypertension. The model showed good fit, and suggests that most change in cognition in very elderly people is small, and depends on their baseline state and on treatment. Additional work is needed to understand whether this modelling approach is well suited to the valuation of small effects, especially in the face of mortality differences between treatment groups.ClinicalTrials.gov NCT0012281

    Cyanide Toxicokinetics: The Behavior of Cyanide, Thiocyanate and 2-Amino-2-Thiazoline-4-Carboxylic Acid in Multiple Animal Models

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    Cyanide causes toxic effects by inhibiting cytochrome c oxidase, resulting in cellular hypoxia and cytotoxic anoxia, and can eventually lead to death. Cyanide exposure can be verified by direct analysis of cyanide concentrations or analyzing its metabolites, including thiocyanate (SCN−) and 2-amino-2-thiazoline-4-carboxylic acid (ATCA) in blood. To determine the behavior of these markers following cyanide exposure, a toxicokinetics study was performed in three animal models: (i) rats (250–300 g), (ii) rabbits (3.5–4.2 kg) and (iii) swine (47–54 kg). Cyanide reached a maximum in blood and declined rapidly in each animal model as it was absorbed, distributed, metabolized and eliminated. Thiocyanate concentrations rose more slowly as cyanide was enzymatically converted to SCN−. Concentrations of ATCA did not rise significantly above the baseline in the rat model, but rose quickly in rabbits (up to a 40-fold increase) and swine (up to a 3-fold increase) and then fell rapidly, generally following the relative behavior of cyanide. Rats were administered cyanide subcutaneously and the apparent half-life (t1/2) was determined to be 1,510 min. Rabbits were administered cyanide intravenously and the t1/2 was determined to be 177 min. Swine were administered cyanide intravenously and the t1/2 was determined to be 26.9 min. The SCN−t1/2 in rats was 3,010 min, but was not calculated in rabbits and swine because SCN−concentrations did not reach a maximum. The t1/2 of ATCA was 40.7 and 13.9 min in rabbits and swine, respectively, while it could not be determined in rats with confidence. The current study suggests that cyanide exposure may be verified shortly after exposure by determining significantly elevated cyanide and SCN− in each animal model and ATCA may be used when the ATCA detoxification pathway is significant

    Transcriptomic Characterization of Tuberculous Sputum Reveals a Host Warburg Effect and Microbial Cholesterol Catabolism.

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    The crucial transmission phase of tuberculosis (TB) relies on infectious sputum and yet cannot easily be modeled. We applied one-step RNA sequencing (RNA-Seq) to sputum from infectious TB patients to investigate the host and microbial environments underlying transmission of Mycobacterium tuberculosis. In such TB sputa, compared to non-TB controls, transcriptional upregulation of inflammatory responses, including an interferon-driven proinflammatory response and a metabolic shift toward glycolysis, was observed in the host. Among all bacterial sequences in the sputum, approximately 1.5% originated from M. tuberculosis, and its transcript abundance was lower in HIV-1-coinfected patients. Commensal bacterial abundance was reduced in the presence of M. tuberculosis infection. Direct alignment to the genomes of the predominant microbiota species also reveals differential adaptation, whereby firmicutes (e.g., streptococci) displayed a nonreplicating phenotype with reduced transcription of ribosomal proteins and reduced activities of ATP synthases, while Neisseria and Prevotella spp. were less affected. The transcriptome of sputum M. tuberculosis more closely resembled aerobic replication and shared similarity in carbon metabolism to in vitro and in vivo models with significant upregulation of genes associated with cholesterol metabolism and downstream propionate detoxification pathways. In addition, and counter to previous reports on intracellular M. tuberculosis infection in vitro, M. tuberculosis in sputum was zinc, but not iron, deprived, and the phoP loci were also significantly downregulated, suggesting that the pathogen is likely extracellular in location. IMPORTANCE Although a few studies have described the microbiome composition of TB sputa based on 16S ribosomal DNA, these studies did not compare to non-TB samples and the nature of the method does not allow any functional inference. This is the first study to apply such technology using clinical specimens and obtained functional transcriptional data on all three aspects simultaneously. We anticipate that an improved understanding on the biological interactions in the respiratory tract may also allow novel interventions, such as those involving microbiome manipulation or inhibitor targeting disease-specific metabolic pathways

    An International Urogynecological Association (IUGA)/International Continence Society (ICS) joint report on the terminology for female anorectal dysfunction.

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    INTRODUCTION: The terminology for anorectal dysfunction in women has long been in need of a specific clinically-based Consensus Report. METHODS: This Report combines the input of members of the Standardization and Terminology Committees of two International Organizations, the International Urogynecological Association (IUGA) and the International Continence Society (ICS), assisted on Committee by experts in their fields to form a Joint IUGA/ICS Working Group on Female Anorectal Terminology. Appropriate core clinical categories and sub classifications were developed to give an alphanumeric coding to each definition. An extensive process of twenty rounds of internal and external review was developed to exhaustively examine each definition, with decision-making by collective opinion (consensus). RESULTS: A Terminology Report for anorectal dysfunction, encompassing over 130 separate definitions, has been developed. It is clinically based with the most common diagnoses defined. Clarity and user-friendliness have been key aims to make it interpretable by practitioners and trainees in all the different specialty groups involved in female pelvic floor dysfunction. Female-specific anorectal investigations and imaging (ultrasound, radiology and MRI) has been included whilst appropriate figures have been included to supplement and help clarify the text. Interval review (5-10 years) is anticipated to keep the document updated and as widely acceptable as possible. CONCLUSION: A consensus-based Terminology Report for female anorectal dysfunction terminology has been produced aimed at being a significant aid to clinical practice and a stimulus for research. Neurourol. Urodynam. 36:10-34, 2017. © 2016 Wiley Periodicals, Inc., and The International Urogynecological Association

    Cognitive frailty: rational and definition from an (I.A.N.A./I.A.G.G.) international consensus group.

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    The frailty syndrome has recently attracted attention of the scientific community and public health organizations as precursor and contributor of age-related conditions (particularly disability) in older persons. in parallel, dementia and cognitive disorders also represent major healthcare and social priorities. although physical frailty and cognitive impairment have shown to be related in epidemiological studies, their pathophysiological mechanisms have been usually studied separately. an international Consensus Group on “Cognitive Frailty” was organized by the international academy on nutrition and aging (i.a.n.a) and the international association of Gerontology and Geriatrics (i.a.G.G) on april 16th, 2013 in toulouse (France). the present report describes the results of the Consensus Group and provides the first definition of a “Cognitive Frailty” condition in older adults. specific aim of this approach was to facilitate the design of future personalized preventive interventions in older persons. Finally, the Group discussed the use of multidomain interventions focused on the physical, nutritional, cognitive and psychological domains for improving the well-being and quality of life in the elderly. the consensus panel proposed the identification of the so-called “cognitive frailty” as an heterogeneous clinical manifestation characterized by the simultaneous presence of both physical frailty and cognitive impairment. in particular, the key factors defining such a condition include: 1) presence of physical frailty and cognitive impairment (Cdr=0.5); and 2) exclusion of concurrent ad dementia or other dementias. under different circumstances, cognitive frailty may represent a precursor of neurodegenerative processes. a potential for reversibility may also characterize this entity. a psychological component of the condition is evident and concurs at increasing the vulnerability of the individual to stressors
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