25 research outputs found

    Potential of the active heat pulse method with fiber optic temperature sensing for estimation of water content and infiltration in agricultural soils

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    The principle of temperature measurement along a fiber optic cable is based on the thermal sensitivity of the relative intensities of backscattered Raman Stokes and anti Stokes photons that arise from collisions with electrons in the core of the glass fiber. A laser pulse, generated by the Distributed Temperature Sensing unit DTS, traversing a fiber optic cable will result in Raman backscatter at two frequencies, referred to as Stokes and anti-Stokes

    Heated fiber optic distributed temperature sensing for measuring soil volumetric heat capacity and water content: A dual probe heat-pulse approach

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    The first feasibility study of using dual-probe heated fiber optics with distributed temperature sensing to measure soil volumetric heat capacity and soil water content is presented. Although results using different combinations of cables demonstrate feasibility, further work is needed to gain accuracy, including a model to account for the finite dimension and the thermal influence of the probes. Implementation of the dual-probe heat-pulse (DPHP) approach for measurement of volumetric heat capacity (C) and water content (θ) with distributed temperature sensing heated fiber optic (FO) systems presents an unprecedented opportunity for environmental monitoring (e.g., simultaneous measurement at thousands of points). We applied uniform heat pulses along a FO cable and monitored the thermal response at adjacent cables. We tested the DPHP method in the laboratory using multiple FO cables at a range of spacings. The amplitude and phase shift in the heat signal with distance was found to be a function of the soil volumetric heat capacity. Estimations of C at a range of moisture contents (θ = 0.09– 0.34 m3 m−3) suggest the feasibility of measurement via responsiveness to the changes in θ, although we observed error with decreasing soil water contents (up to 26% at θ = 0.09 m3 m−3). Optimization will require further models to account for the finite radius and thermal influence of the FO cables. Although the results indicate that the method shows great promise, further study is needed to quantify the effects of soil type, cable spacing, and jacket configurations on accuracy

    Mapping variability of soil water content and flux across 1¿1000 m scales using the actively heated fiber optic method

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    The Actively Heated Fiber Optic (AHFO) method is shown to be capable of measuring soil water content several times per hour at 0.25 m spacing along cables of multiple kilometers in length. AHFO is based on distributed temperature sensing (DTS) observation of the heating and cooling of a buried fiber-optic cable resulting from an electrical impulse of energy delivered from the steel cable jacket. The results presented were collected from 750 m of cable buried in three 240 m colocated transects at 30, 60, and 90 cm depths in an agricultural field under center pivot irrigation. The calibration curve relating soil water content to the thermal response of the soil to a heat pulse of 10 W m−1 for 1 min duration was developed in the lab. This calibration was found applicable to the 30 and 60 cm depth cables, while the 90 cm depth cable illustrated the challenges presented by soil heterogeneity for this technique. This method was used to map with high resolution the variability of soil water content and fluxes induced by the nonuniformity of water application at the surface

    The accuracy of diagnostic indicators for coeliac disease: A systematic review and meta-analysis

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    Background: The prevalence of coeliac disease (CD) is around 1%, but diagnosis is challenged by varied presentation and non-specific symptoms and signs. This study aimed to identify diagnostic indicators that may help identify patients at a higher risk of CD in whom further testing is warranted. // Methods: International guidance for systematic review methods were followed and the review was registered at PROSPERO (CRD42020170766). Six databases were searched until April 2021. Studies investigating diagnostic indicators, such as symptoms or risk conditions, in people with and without CD were eligible for inclusion. Risk of bias was assessed using the QUADAS-2 tool. Summary sensitivity, specificity, and positive predictive values were estimated for each diagnostic indicator by fitting bivariate random effects meta-analyses. // Findings: 191 studies reporting on 26 diagnostic indicators were included in the meta-analyses. We found large variation in diagnostic accuracy estimates between studies and most studies were at high risk of bias. We found strong evidence that people with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease are more likely than the general population to have CD. Symptoms, psoriasis, epilepsy, inflammatory bowel disease, systemic lupus erythematosus, fractures, type 2 diabetes, and multiple sclerosis showed poor diagnostic ability. A sensitivity analysis revealed a 3-fold higher risk of CD in first-degree relatives of CD patients. // Conclusions: Targeted testing of individuals with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease could improve case-finding for CD, therefore expediting appropriate treatment and reducing adverse consequences. Migraine and chronic liver disease are not yet included as a risk factor in all CD guidelines, but it may be appropriate for these to be added. Future research should establish the diagnostic value of combining indicators

    Challenges of adapting English médium instruction into the Spanish university curricula and some novel solutions

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    The integration of the Spanish university system in the European Higher Education Area (EHEA) demands a series of concrete proposals. As we advance in the implementation of the process of Bologna, it is necessary to contemplate a new paradigm of teaching/learning. Central to this new paradigm is the adaptation of the curricula into the English language medium (EMI). Among many strategies for internationalization of the Universidad Politécnica de Madrid (UPM) under adoption, this university has funded a project TechEnglish intends to facilitate the conversion of subjects and eventually degree programs into the delivery in the English Language. This paper details a work in progress and describes the collaboration between content teachers and applied linguistics. The three collaborative actions are currently underway: observation of classes by applied linguists, seminar delivery on topics requested by the content teachers, and materials development with the help of teaching assistants. We are convinced that this collaboration is the necessary ingredient to promote teaching and learning through English at our university

    Fostering English-taught higher education programs in a Spanish university: the "TechEnglish" innovative project

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    In recent years, coinciding with adjustments to the Bologna process, many European universities have attempted to improve their international profile by increasing course offerings in English. According to the Institute of International Education (IIE), Spain has notably increased its English-taught higher education programs, ranking fifth in the list of European countries by number of English-taught Master's programs in 2013. This article presents the goals and preliminary results of an on-going innovative education project (TechEnglish) that aims to promote course offerings in English at the Technical University of Madrid (Universidad Politécnica de Madrid, UPM). The UPM is the oldest and largest of all Technical Universities in Spain. It offers graduate and postgraduate programs that cover all the engineering disciplines as well as architecture. Currently, the UPM has no specific bilingual/multilingual program to promote teaching in English, although there is an Educational Model Whitepaper (with a focus on undergraduate degrees) that promotes the development of activities like an International Semester or a unique shared curriculum. The TechEnglish project is an attempt to foster courses taught in English at 7 UPM Technical Schools, including students and 80 faculty members. Four tasks were identified: (1) to design a university wide framework to increase course offerings, (2) to identify administrative difficulties, (3) to increase visibility of courses offered, and (4) to disseminate the results of the project. First, to design a program we analyzed existing programs at other Spanish universities, and other projects and efforts already under way at the UPM. A total of 13 plans were analyzed and classified according to their relation with students (learning), professors (teaching), administration, course offerings, other actors/institutions within the university (e.g., language departments), funds and projects, dissemination activities, mobility plans and quality control. Second, to begin to identify administrative and organizational difficulties in the implementation of teaching in English, we first estimated the current and potential course offerings at the undergraduate level at the UPM using a survey (student, teacher and administrative demand, level of English and willingness to work in English). Third, to make the course offerings more attractive for both Spanish and international students we examined the way the most prestigious universities in Spain and in Europe try to improve the visibility of their academic offerings in English. Finally, to disseminate the results of the project we created a web page and a workspace on the Moodle education platform and prepared conferences and workshops within the UPM. Preliminary results show that increasing course offerings in English is an important step to promote the internationalization of the University. The main difficulties identified at the UPM were related to how to acknowledge/certify the departments, teachers or students involved in English courses, how students should register for the courses, how departments should split and schedule the courses (Spanish and English), and the lack of qualified personnel. A concerted effort could be made to increase the visibility of English-taught programs offered on-line

    Determinación de la patogeneidad de Pythium spp. sobre pepino (Cucumis sativus), tomate (Lycopersicon esculentum L.) y judía (Phaseolus vugarisL.)

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    En este estudio se pretende determinar la patogeneicidad de Pythium Pringsheim sobre semillas y plantas de pepino (Cucumis sativus L.), tomate (Lycopersicon esculentum L.) y judía (Phaseolus vulgaris L.). Con este fin, se han inoculado dos aislados de Pythium aphanidermatum, uno de P. deliense, dos de P. irregulare, dos de P. ultimum y uno de P. paroecandrum sobre semilla sembrada en vermiculita desinfectada con vapor de agua durante 1 hora a 120ºC. Las semillas inoculadas se mantuvieron durante los 10 días que duró cada uno de los dos experimentos en cámara controlada a 20 y 28ºC, luminosidad de 2.500 lux durante 12 h / día. Se realizaron dos nuevos experimentos inoculando los mismos aislados sobre plantas de pepino en estado vegetativo de 4 y 9 hojas. Los cultivos se mantuvieron durante 60 días en cámara controlada a 28ºC (14 h / día) y 18ºC (10h / día), luminosidad de 3.500 lux durante 14 h / dia. En las inoculaciones en semilla de tomate (c.v. Robin) con P. irregulare, P. ultimum 1 y P. paroecandrum a 20ºC no se observa emergencias. A 28ºC el número de plántulas emergidas es mayor, salvo en las inoculaciones con P. paroecandrum que permanece constante. En las inoculaciones sobre semilla de judía (c.v. Femira), la emergencia de plántulas es mayor a 20 que a 28ºC y la patogeneicidad de P. aphanidermatum y P. deliense es mayor que la de P. irregulare y P. ultimum. La semilla de pepino (c.v. Serena) es la más sensible a la patogeneicidad de los distintos aislados, a excepción de P paroecandrum..

    Relaciones entre diferentes razas de maíz españolas y dos sintéticos americanos

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    Veintiuna razas de maíz (Zea mays L.) que representan a toda la geografía española excepto al norte y noroeste, así como dos sintéticos americanos obtenidos de las poblaciones Lancaster y Stiff Stalk Synthetic, han sido clasificadas en base a 19 caracteres morfológicos de la planta, penacho, mazorca y grano. Se utilizó un Análisis Discriminante paso a paso y un Análisis Cluster por ligamiento con el centroide. El porcentaje de casos correctamente clasificados variaba desde un 60% en la raza Andaluz x Basto a 97% de la raza Blanco. Tanto en el análisis canónico como en la agrupación jerárquica basada en la Distancia Euclídea, la relación entre razas, en algunos casos, se correspondía con su origen geográfico. Las razas españolas están más próximas al sintético americano Lancaster y Compositae A que a BS-13(S2)C2. Un sistema de clasificación jerárquica basado en caracteres morfológicos y fisiológicos puede proporcionar buena medida de la relación de las razas españolas

    Prospección de las micosis en los invernaderos de Villa del Prado (Madrid) y su incidencia en el cultivo de judía (Phaseolus vulgaris L.)

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