3,686 research outputs found
Cross-coupled doa trackers
A new robust, low complexity algorithm for multiuser tracking is proposed, modifying the two-stage parallel architecture of the estimate-maximize (EM) algorithm. The algorithm copes with spatially colored noise, large differences in source powers, multipath, and crossing trajectories. Following a discussion on stability, the simulations demonstrate an asymptotic and tracking behavior that neither the EM nor a nonparallelized tracker can emulate.Peer ReviewedPostprint (published version
Fire resistance of axially loaded slender concrete filled steel tubular columns. Development of a Three-dimensional numerical model and comparison with eurocode 4
[EN] In recent years, concrete filled tubular (CFT) columns have become popular among designers and structural engineers, due to a series of
highly appreciated advantages: high load-bearing capacity, high seismic resistance, attractive appearance, reduced column footing, fast
construction technology and high fire resistance without external protection. In a fire, the degradation of the material properties will cause
CFT columns to become highly nonlinear and inelastic, which makes it quite difficult to predict their failure. In fact, it is still not possible for
analytical methods to predict with enough accuracy the behaviour of columns of this kind when exposed to fire. Numerical models are therefore
widely sought. Many numerical simulations have been carried out worldwide, without obtaining satisfactory results. This work proposes
a three-dimensional numerical model for studying the actual fire behaviour of columns of this kind. This model was validated by comparing
the simulation results with fire resistance tests carried out by other researchers, as well as with the predictions of the Eurocode 4 simplified
calculation model.Espinós Capilla, A.; Hospitaler Pérez, A.; Romero, ML. (2009). Fire resistance of axially loaded slender concrete filled steel tubular columns. Development of a Three-dimensional numerical model and comparison with eurocode 4. Acta Polytechnica. 49(1):39-43. http://hdl.handle.net/10251/102170S394349
Molecular diagnosis of Theileria and Babesia species infecting cattle in Northern Spain using reverse line blot macroarrays
BACKGROUND: Piroplasmosis in cattle is caused by tick-borne haemoprotozoan parasites of the genera Theileria and Babesia. Molecular detection techniques offer higher sensitivity and specificity than microscopy examination methods and serological tests. A reverse line blot (RLB) macroarray that included generic and species-specific probes for Theileria annulata, Theileria buffeli, Babesia bovis, Babesia bigemina, Babesia divergens and Babesia major was used to study the presence and identity of the piroplasm species infecting 263 bovine blood samples from 79 farms, most of them in Northern Spain. Microscopy examination of blood smears and haematology were also performed whenever possible to identify animals with parasitaemia. RESULTS: RLB hybridisation identified infection in 54.0% of the samples, whereas only 28.8% were positive by microscopy examination. The most frequently found species was T. buffeli, present in 42.6% of the samples. T. annulata was found in 22 samples (8.4%) from 12 farms, including 9 farms (14 samples) located in Northern Spain where presence of the vector is not very common. Babesia infections were less frequently detected: B. major was found in 3.0% of the samples, B. bigemina in 2.7%, B. bovis in 2.3% and B. divergens in 1.1%. Mixed infections were detected in 14 samples, accounting for six different combinations of species. CONCLUSION: This is the first report in which B. major and B. divergens have been detected in Spain using molecular identification techniques and the first time that B. bovis has been detected in Northern Spain. The detection of T. annulata in Northern Spain suggests that the distribution of Mediterranean theileriosis might be changing. Samples with positive RLB hybridisation but negative microscopy had haematology values within the normal ranges suggesting that they corresponded to chronic carriers that may serve as reservoirs of the infection. In this sense, sensitive and specific laboratorial tests like RLB that clearly identify the parasite and can detect subclinical infections are essential to establish good control measures
Assessment of exposure to piroplasms in sheep grazing in communal mountain pastures by using a multiplex DNA bead-based suspension array
BACKGROUND: Piroplasms are tick-borne hemoprotozoans with a major impact on extensive management systems. Detection of sub-clinical low-level carriers, which can act as source of infection for vector ticks, is key to protect livestock trade and facilitate preventive control programs. The purpose of this study was to develop a method for the detection of ovine piroplasms and to use it in a field study aimed at investigating piroplasms infection in semi-extensive production systems in the Basque Country (northern Spain). METHODS: A DNA bead-based suspension array using the Luminex® xMAP technology that included a generic Theileria-Babesia control probe, 6 species-specific probes, and an internal control probe was developed to detect and identify piroplasms that infect sheep. To monitor piroplasm infection in clinically healthy sheep from 4 flocks that share communal mountain pastures, blood samples were collected during 2 grazing seasons. RESULTS: Piroplasms were detected in 48% (214/446) of blood samples, nearly half of them (49.1%, 105/214) as mixed infections. Five different piroplasms were identified: Theileria sp. OT3 in 34.8% of the samples, Theileria ovis in 20.9%, and at lower prevalences Babesia motasi (12.3%), Theileria luwenshuni/OT1 (10.5%) and Babesia ovis (6.3%). Despite differences among flocks associated to differences in management, an increasing trend in the incidence of piroplasm infection with increasing age of animals after increased tick exposure was observed. This increment could be attributed to continued re-infection associated with re-exposure to ticks at grazing. Ticks were collected from animals (4 species) and vegetation (8 species), and associations between tick abundance seasonality and risk of infection with the different piroplasms were established. CONCLUSION: The multiplex Luminex® xMAP procedure is a rapid and high throughput technique that provided highly specific and sensitive identification of single and mixed piroplasm infections in blood of sheep carriers. This study confirmed a situation of endemic stability for piroplasm infection in the region, where infection is present in the absence of clinical signs, and mountain grazing allows for sufficient inoculation rates to maintain such situation
The aquatic ecosystem, a good environment for the horizontal transfer of antimicrobial resistance and virulence-associated factors among extended spectrum ß-lactamases producing E. coli
One of the main public health problems nowadays is the increase of antimicrobial resistance,
both in the hospital environment and outside it (animal environment, food and aquatic ecosystems,
among others). It is necessary to investigate the virulence-associated factors and the ability of
horizontal gene transfer among bacteria for a better understanding of the pathogenicity and the
mechanisms of dissemination of resistant bacteria. Therefore, the objective of this work was to
detect several virulence factors genes (fimA, papC, papG III, cnf1, hlyA and aer) and to determine the
conjugative capacity in a wide collection of extended-spectrum β-lactamases-producing E. coli isolated
from different sources (human, food, farms, rivers, and wastewater treatment plants). Regarding
virulence genes, fimA, papC, and aer were distributed throughout all the studied environments, papG
III was mostly related to clinical strains and wastewater is a route of dissemination for cnf1 and hlyA.
Strains isolated from aquatic environments showed an average conjugation frequencies of 1.15 × 10−1
± 5 × 10−1
, being significantly higher than those observed in strains isolated from farms and food
(p < 0.05), with frequencies of 1.53 × 10−4 ± 2.85 × 10−4 and 9.61 × 10−4 ± 1.96 × 10−3
, respectively. The
reported data suggest the importance that the aquatic environment (especially WWTPs) acquires for
the exchange of genes and the dispersion of resistance. Therefore, specific surveillance programs of
AMR indicators in wastewaters from animal or human origin are needed, in order to apply sanitation
measures to reduce the burden of resistant bacteria arriving to risky environments as WWTPs
The aquatic ecosystem, a good environment for the horizontal transfer of antimicrobial resistance and virulence-associated factors among extended spectrum beta-lactamases producing E. coli
One of the main public health problems nowadays is the increase of antimicrobial resistance,
both in the hospital environment and outside it (animal environment, food and aquatic ecosystems,
among others). It is necessary to investigate the virulence-associated factors and the ability of
horizontal gene transfer among bacteria for a better understanding of the pathogenicity and the
mechanisms of dissemination of resistant bacteria. Therefore, the objective of this work was to
detect several virulence factors genes (fimA, papC, papG III, cnf1, hlyA and aer) and to determine the
conjugative capacity in a wide collection of extended-spectrum β-lactamases-producing E. coli isolated
from different sources (human, food, farms, rivers, and wastewater treatment plants). Regarding
virulence genes, fimA, papC, and aer were distributed throughout all the studied environments, papG
III was mostly related to clinical strains and wastewater is a route of dissemination for cnf1 and hlyA.
Strains isolated from aquatic environments showed an average conjugation frequencies of 1.15 × 10−1
± 5 × 10−1
, being significantly higher than those observed in strains isolated from farms and food
(p < 0.05), with frequencies of 1.53 × 10−4 ± 2.85 × 10−4 and 9.61 × 10−4 ± 1.96 × 10−3
, respectively. The
reported data suggest the importance that the aquatic environment (especially WWTPs) acquires for
the exchange of genes and the dispersion of resistance. Therefore, specific surveillance programs of
AMR indicators in wastewaters from animal or human origin are needed, in order to apply sanitation
measures to reduce the burden of resistant bacteria arriving to risky environments as WWTPs
One Health Approach: An Overview of Q Fever in Livestock, Wildlife and Humans in Asturias (Northwestern Spain)
This study aimed to investigate the seroprevalence of C. burnetii in domestic ruminants, wild ungulates, as well as the current situation of Q fever in humans in a small region in northwestern Spain where a close contact at the wildlife–livestock–human interface exists, and information on C. burnetii infection is scarce. Seroprevalence of C. burnetii was 8.4% in sheep, 18.4% in cattle, and 24.4% in goats. Real-time PCR analysis of environmental samples collected in 25 livestock farms detected Coxiella DNA in dust and/or aerosols collected in 20 of them. Analysis of sera from 327 wild ungulates revealed lower seroprevalence than that found in domestic ruminants, with 8.4% of Iberian red deer, 7.3% chamois, 6.9% fallow deer, 5.5% European wild boar and 3.5% of roe deer harboring antibodies to C. burnetii. Exposure to the pathogen in humans was determined by IFAT analysis of 1312 blood samples collected from patients admitted at healthcare centers with Q fever compatible symptoms, such as fever and/or pneumonia. Results showed that 15.9% of the patients had IFAT titers ≥ 1/128 suggestive of probable acute infection. This study is an example of a One Health approach with medical and veterinary institutions involved in investigating zoonotic diseasesThis work was funded by INIA—Spanish National Institute for Agricultural and Food Research and Technology (RTA2017-00055-C02-02), the European Regional Development Funds (ERDF), and PCTI 2018–2020 (GRUPIN: IDI2018-000237)S
Confidentiality in Medical Oaths: (when the white crow becomes gray...)
La confidencialidad, junto con los principios éticos de beneficencia y no-maleficencia, es la norma más señalada en los Juramentos Médicos de la actualidad. A pesar de ello, el avance científico-técnico en la Medicina ha hecho que constituya una de las reglas más controvertidas por sus excepciones. En consecuencia, los objetivos del presente trabajo son analizar comparativamente la regla de confidencialidad en los Juramentos Médicos de distintos lugares, épocas, orígenes y en diferentes versiones del Hipocrático y a su vez, determinar en aquellos Juramentos que expresan esta regla, qué es lo que se debe guardar en secreto y con qué grado de compromiso (absoluto o "prima facie"). De los treinta y seis Juramentos analizados, veintisiete manifiestan esta regla y nueve, no. No se halló relación entre la manifestación de esta regla y el lugar, época, origen y distintas versiones del Hipocrático. La mayoría sugiere no revelar lo visto u oído en relación con lo médico, al igual que el Hipocrático. Siete textos señalan que la confidencialidad debe ser absoluta y cuatro señalan excepciones en relación con los principios de beneficencia y justicia y el deber moral de no dañar a terceras partes. Dos fórmulas especifican la protección de la privacidad. En síntesis, la confidencialidad es considerada en estos tiempos como un deber moral para el bien del paciente y por respeto a su autonomía; pero a pesar de ello, en la actualidad en Medicina se está replanteando el deber de guardar el secreto en una forma absoluta.Confidentiality, together with the ethical principles of beneficence and non-maleficence, is the most important rule in Medical Oaths at the present time. However, the scientific-technical advances in medicine have made this rule one of the most controversial ones because of its exceptions. In consequence, the aim of the present paper is to comparatively analyze the rule of confidentiality in Medical Oaths of different places, times, origins and in different versions of the Hippocratic Oath in order to determine what should be kept a secret and with what degree of commitment (absolute or "prima facie"). Of the thirty six analyzed Oaths, twenty-seven manifest this rule and nine do not. No relation was found between the manifestation of this rule and the place, time, origin and different versions of the Hippocratic Oath. Most pledges suggest not to reveal what has been seen or heard during the medical act, the same as in the Hippocratic Oath. Seven texts point out that confidentiality should be absolute and four give exceptions in connection with beneficence and justice principles and the moral duty of causing no damage to third parties. Two pledges specify protection of privacy. In conclusion, today confidentiality is considered to be a moral duty for the benefit of the patient and out of consideration for his autonomy; however, at the present time in medicine the duty of keeping absolute secrecy is being reconsidered.Fil: Gelpi, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Pérez, Marta L.. Universidad Nacional de La Plata; ArgentinaFil: Rancich, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Mainetti, Jose Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Para Progreso Medicina-hospital Privado. Instituto de Bioética y Humanidades Médicas; Argentin
Accidentes laborales en veterinarios rurales
El ejercicio de la Veterinaria está asociado a numerosos riesgos ocupacionales. Los objetivos de este trabajo fueron estimar la frecuencia de veterinarios rurales que tuvieron accidentes laborales (AL), describir tipo de lesión y elementos involucrados, factores asociados y ausencia laboral. Se desarrolló un censo en veterinarios rurales (N= 741) que asistieron a reuniones obligatorias de capacitación continua. La tasa de respuesta a un cuestionario estructurado anónimo fue del 75.8% (n= 562). El análisis de los datos incluyó: χ2, t de Student, correlación de Pearson y regresión logística. El 97,1% había sufrido accidentes durante el ejercicio profesional, el 59,6% había requerido atención médica y el 81,4% padecía alguna dolencia derivada de su trabajo. El 52,1% tuvo al menos un día de ausencia laboral debido a accidentes de trabajo (37,9 ± 51,7 días). Sexo, edad y antigüedad profesional estuvieron significativamente asociados con la ocurrencia de AL in labore. en el análisis bivariante, pero no en el multivariante, probablemente debido al muy bajo número de entrevistados que no sufrieron AL. Algunas características de los profesionales, unida a la especial naturaleza de los pacientes, la existencia de instalaciones inapropiadas para ejercer la práctica clínica en condiciones de campo y la necesidad de trasladarse en vehículos automotores para entrar en contacto con los pacientes pueden contribuir para que esta profesión tenga un alto riesgo laboral
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