1000 resultados para Indicadors ambientals -- Mètodes estadístics
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The vast majority of the biology of a newly sequenced genome is inferred from the set of encoded proteins. Predicting this set is therefore invariably the first step after the completion of the genome DNA sequence. Here we review the main computational pipelines used to generate the human reference protein-coding gene sets.
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The recent availability of the chicken genome sequence poses the question of whether there are human protein-coding genes conserved in chicken that are currently not included in the human gene catalog. Here, we show, using comparative gene finding followed by experimental verification of exon pairs by RT–PCR, that the addition to the multi-exonic subset of this catalog could be as little as 0.2%, suggesting that we may be closing in on the human gene set. Our protocol, however, has two shortcomings: (i) the bioinformatic screening of the predicted genes, applied to filter out false positives, cannot handle intronless genes; and (ii) the experimental verification could fail to identify expression at a specific developmental time. This highlights the importance of developing methods that could provide a reliable estimate of the number of these two types of genes.
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Background: There is growing evidence that traffic-related air pollution reduces birth weight. Improving exposure assessment is a key issue to advance in this research area.Objective: We investigated the effect of prenatal exposure to traffic-related air pollution via geographic information system (GIS) models on birth weight in 570 newborns from the INMA (Environment and Childhood) Sabadell cohort.Methods: We estimated pregnancy and trimester-specific exposures to nitrogen dioxide and aromatic hydrocarbons [benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene (BTEX)] by using temporally adjusted land-use regression (LUR) models. We built models for NO2 and BTEX using four and three 1-week measurement campaigns, respectively, at 57 locations. We assessed the relationship between prenatal air pollution exposure and birth weight with linear regression models. We performed sensitivity analyses considering time spent at home and time spent in nonresidential outdoor environments during pregnancy.Results: In the overall cohort, neither NO2 nor BTEX exposure was significantly associated with birth weight in any of the exposure periods. When considering only women who spent < 2 hr/day in nonresidential outdoor environments, the estimated reductions in birth weight associated with an interquartile range increase in BTEX exposure levels were 77 g [95% confidence interval (CI), 7–146 g] and 102 g (95% CI, 28–176 g) for exposures during the whole pregnancy and the second trimester, respectively. The effects of NO2 exposure were less clear in this subset.Conclusions: The association of BTEX with reduced birth weight underscores the negative role of vehicle exhaust pollutants in reproductive health. Time–activity patterns during pregnancy complement GIS-based models in exposure assessment.
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Background: Few studies have used longitudinal ultrasound measurements to assess the effect of traffic-related air pollution on fetal growth.Objective: We examined the relationship between exposure to nitrogen dioxide (NO2) and aromatic hydrocarbons [benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene (BTEX)] on fetal growth assessed by 1,692 ultrasound measurements among 562 pregnant women from the Sabadell cohort of the Spanish INMA (Environment and Childhood) study.Methods: We used temporally adjusted land-use regression models to estimate exposures to NO2 and BTEX. We fitted mixed-effects models to estimate longitudinal growth curves for femur length (FL), head circumference (HC), abdominal circumference (AC), biparietal diameter (BPD), and estimated fetal weight (EFW). Unconditional and conditional SD scores were calculated at 12, 20, and 32 weeks of gestation. Sensitivity analyses were performed considering time–activity patterns during pregnancy.Results: Exposure to BTEX from early pregnancy was negatively associated with growth in BPD during weeks 20–32. None of the other fetal growth parameters were associated with exposure to air pollution during pregnancy. When considering only women who spent 2 hr/day in nonresidential outdoor locations, effect estimates were stronger and statistically significant for the association between NO2 and growth in HC during weeks 12–20 and growth in AC, BPD, and EFW during weeks 20–32.Conclusions: Our results lend some support to an effect of exposure to traffic-related air pollutants from early pregnancy on fetal growth during mid-pregnancy.
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Background: Choosing an adequate measurement instrument depends on the proposed use of the instrument, the concept to be measured, the measurement properties (e.g. internal consistency, reproducibility, content and construct validity, responsiveness, and interpretability), the requirements, the burden for subjects, and costs of the available instruments. As far as measurement properties are concerned, there are no sufficiently specific standards for the evaluation of measurement properties of instruments to measure health status, and also no explicit criteria for what constitutes good measurement properties. In this paper we describe the protocol for the COSMIN study, the objective of which is to develop a checklist that contains COnsensus-based Standards for the selection of health Measurement INstruments, including explicit criteria for satisfying these standards. We will focus on evaluative health related patient-reported outcomes (HR-PROs), i.e. patient-reported health measurement instruments used in a longitudinal design as an outcome measure, excluding health care related PROs, such as satisfaction with care or adherence. The COSMIN standards will be made available in the form of an easily applicable checklist.Method: An international Delphi study will be performed to reach consensus on which and how measurement properties should be assessed, and on criteria for good measurement properties. Two sources of input will be used for the Delphi study: (1) a systematic review of properties, standards and criteria of measurement properties found in systematic reviews of measurement instruments, and (2) an additional literature search of methodological articles presenting a comprehensive checklist of standards and criteria. The Delphi study will consist of four (written) Delphi rounds, with approximately 30 expert panel members with different backgrounds in clinical medicine, biostatistics, psychology, and epidemiology. The final checklist will subsequently be field-tested by assessing the inter-rater reproducibility of the checklist.Discussion: Since the study will mainly be anonymous, problems that are commonly encountered in face-to-face group meetings, such as the dominance of certain persons in the communication process, will be avoided. By performing a Delphi study and involving many experts, the likelihood that the checklist will have sufficient credibility to be accepted and implemented will increase.
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Background: Analyzing social differences in the health of adolescents is a challenge. The accuracy of adolescent's report on familial socio-economic position is unknown. The aims of the study were to examine the validity of measuring occupational social class and family level of education reported by adolescents aged 12 to 18, and the relationship between social position and self-reported health.Methods: A sample of 1453 Spanish adolescents 12 to 18 years old from urban and rural areas completed a self-administered questionnaire including the Child Health and Illness Profile-Adolescent Edition (CHIP-AE), and data on parental occupational social class (OSC) and level of education (LE). The responsible person for a sub-sample of teenagers (n = 91) were interviewed by phone. Kappa coefficients were estimated to analyze agreement between adolescents and proxy-respondents, and logistic regression models were adjusted to analyze factors associated with missing answers and disagreements. Effect size (ES) was calculated to analyze the relationship between OSC, LE and the CHIP-AE domain scores.Results: Missing answers were higher for father's (24.2%) and mother's (45.7%) occupational status than for parental education (8.4%, and 8.1% respectively), and belonging to a non-standard family was associated with more incomplete reporting of social position (OR = 4,98; 95%CI = 1,3–18,8) as was agreement between a parent and the adolescent. There were significant social class gradients, most notably for aspects of health related to resilience to threats to illness.ConclusionAdolescents can acceptably self-report on family occupation and level of education. Social class gradients are present in important aspects of health in adolescents.
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Background: The aim of this report is to describe the main characteristics of the design, including response rates, of the Cornella Health Interview Survey Follow-up Study. Methods: The original cohort consisted of 2,500 subjects (1,263 women and 1,237 men) interviewed as part of the 1994 Cornella Health Interview Study. A record linkage to update the address and vital status of the cohort members was carried out using, first a deterministic method, and secondly a probabilistic one, based on each subject's first name and surnames. Subsequently, we attempted to locate the cohort members to conduct the phone follow-up interviews. A pilot study was carried out to test the overall feasibility and to modify some procedures before the field work began. Results: After record linkage, 2,468 (98.7%) subjects were successfully traced. Of these, 91 (3.6%) were deceased, 259 (10.3%) had moved to other towns, and 50 (2.0%) had neither renewed their last municipal census documents nor declared having moved. After using different strategies to track and to retain cohort members, we traced 92% of the CHIS participants. From them, 1,605 subjects answered the follow-up questionnaire. Conclusion: The computerized record linkage maximized the success of the follow-up that was carried out 7 years after the baseline interview. The pilot study was useful to increase the efficiency in tracing and interviewing the respondents.
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Immigrant organisations in the City of Oslo receive support from the government for their daily operation. In order to receive such support, each organisation must be membership-based and have internal democratic procedures. This paper raises the question of how we can understand this combination of support for ethnic based organisations and requirements of membership and internal democracy. It explores the usefulness of two partly overlapping ways of understanding this policy and discusses their interrelationship. Firstly, within the context of the crisis of multiculturalism, the paper discusses whether this combination is based on the aim of strengthening the organisations’ procedural commitment to liberal-democratic principles. Secondly, the paper analyses whether requirements of membership and internal democracy can mainly be understood within the framework of the Nordic model of voluntary organisation. By comparing the policy at three empirical levels, the paper concludes that this combination can mainly be understood within the framework of the traditional historical Nordic model, but that there is an ambiguity in this policy related to minority rights.
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Aquest article intenta examinar la importància d'un tipus determinat d'obra lexicogràfica per a usuaris estrangers: els diccionaris d'aprenentatge, els quals s'han de caracteritzar bàsicament per una transmissió dels significats assequible. El material recollit pretén repassar el contingut d'aquestes publicacions a la tradició anglosaxona i il·lustrar l'estadi inicial de la pràctica castellana a partir dels mètodes lexicogràfics que existeixen actualment des d'aquest punt de vista. Els resultats d'aquests estudis permeten valorar la importància de la compilació dels vocabularis de definició per intentar potenciar la branca de la lexicografia com a ajuda a la pràctica didàctica de l'aprenentatge de l'espanyol com a segona llengua.
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Extreme Vocal Effects (EVE) in music are so recent that few studies have been carried out about how they are physiologically produced and whether they are harmful or not for the human voice.Voice Transformations in real-time are possible nowadays thanks to new technologies and voice processing algorithms. This Master's Thesis pretends to define and classify these new singing techniques and to create a mapping between the physiological aspect of each EVE to its relative spectrumvariations.Voice Transformation Models based on these mappings are proposed and discussed for each one of these EVEs. We also discuss different transformation methods and strategies in order to obtain better results.A subjective evaluation of the results of the transformations is also presented and discussed along with further work, improvements, and working lines on this field.
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L’estudi de les funcions cerebrals humanes s’ha incrementat enormement durant els últims anys donada l’aparició de les imatges funcionals de ressonància magnètica (FMRI). Mentre que la tècnica s’ha emprat principalment en la localització de diferents funcions cerebrals, el problema de classificació d’estats cognitius ha estat poc explorat. L’estudi d’aquest problemaés important perquè pot servir com a eina per a detectar i seguir processoscognitius (seqüències d’estats cognitius) amb la finalitat de diagnosticarproblemes en el moment d’executar una tasca complexa.En aquest treball s’investiguen diferents aproximacions per a detectar l’estat cognitiu d’una persona prenent com a base la seva imatge de ressonància magnètica. En particular, s’han investigat varis mecanismes de sel·lecció de característiques així com mètodes d’aprenentatge automàtic pelproblema de la discriminació d’estats cognitius procedents d’estimuls auditius.Es presenten els resultats d’un estudi sobre estímuls musicals.
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El treball que presentem a continuació desenvolupa un marc teòric i pràctic per a l'avaluació i estudi d'un model generatiu aplicat a tasques discriminatives de senyals sonores sense component harmònica. El model generatiu està basat en la construcció de l'anomenada deep belief network, un tipus de xarxa neuronal generativa que permet realitzar tasques de classificació i regressió com també de reconstrucció dels seus estats interns.A partir de l'anàlisi realitzada hem pogut obtenir resultats en classificació aparellats amb els resultats de l'estat de l'art de classificadors de sons inharmònics. Tot i no establir una clara superioritat envers altres mètodes, el present treball ha permés desenvolupar una anàlisi per almodel avaluat amb moltes possibilitats de millora en un futur per altres treballs. Al llarg del treball es demostra la seva eficàcia en tasques discriminatives, com també la capacitat de reduir la dimensionalitat de les dades d'entrada al model i les possibilitats de reconstruir els seus estats interns per a obtenir unes sortides de dades de la xarxa similars a les entrades de descriptors.El desenvolupament centrat en la deep belief network ens ha permés construir un entorn unificat d'avaluació de diferents mètodes d'aprenentatge, construcció i adequació de diferents descriptors sonors i una posterior visualització d'estats interns del mateix, que han possibilitat una avaluaciócomparativa i unificada respecte altres mètodes classificadors de l'estat de l'art. També ens ha permés desenvolupar una implementació en un llenguatge d'alt nivell, que ha reportat més significància per a l'enteniment i anàlisi del model avaluat, amb una argumentació més sòlida.Els resultats i l'anàlisi que reportem són significatius i positius per al model avaluat, i degut a la poca literatura existent en el camp de classificació de sons inharmònics com els sons percussius,creiem que és una aportació interessant i significativa per al camp en el que s'engloba el treball.
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L’educació és una de les bases més importants del món actual. A través de l’educació formem a les persones amb coneixements i valors indispensables per formar part de la societat. I aquestasocietat avança i evoluciona cada vegada més depressa; la nova societat de la informació, les noves tecnologies, les noves comunicacions… És per això que un àmbit tant important com l’educació també ha d’evolucionar al mateix ritme.Les noves generacions han de ser educades en les noves tecnologies ja que es tornenindispensables. Però a més també es planteja la qüestió de si aquestes innovacionstecnològiques suposen nous mètodes, noves eines, per proporcionar una educació de mésqualitat, que facin desenvolupar encara més les noves capacitats i aptituds dels nens.Un dels objectius principals d’aquest projecte és aquest. Primer cal investigar i preguntar-se si aquests nous avenços tecnològics es troben a l’aula, a l’educació dels més petits i si s’exploten els seus recursos de forma convenient. Llavors podem plantejar que és el que manca, i que espot millorar amb les noves tecnologies.Tots aquests avenços però, poden resultar eines molt complicades i inaccessibles pels nens i es pot acabar optant per no fer-ne ús. Per això en aquest projecte s’estudiarà la viabilitat de fer servir una nova eina, la ReacTable, una interfície tangible, interactiva i que pot proporcionar unús més fàcil, menys agressiu i més intuïtiu que la resta de tecnologies.
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Las nuevas generaciones de estudiantes se caracterizan en que han crecido inmersas en la tecnología digital, hecho que ha cambiado sus costumbres y preferencias en la forma de estudiar. Así que es necesario ingeniar nuevas técnicas de aprendizaje y buscar un complemento al poco atractivo y desmotivador material físico tradicional. Una de las alternativas que se plantean es utilizar juegos educativos como herramienta de aprendizaje, aportándonos innovación, motivación y un aprendizaje activo que no nos aportan técnicas más tradicionales.Esta metodología basada en el uso de juegos educativos puede afectar positivamente en un campo de educación perjudicado como es el área de las ingenierías del área de Tecnologías de la Información y la Comunicación (TIC), donde cada vez son más los jóvenes que deciden no estudiar carreras técnicas. Ante esta situación, aplicar juegos educativos puede ser una buena solución. Este proyecto consistirá en diseñar e implementar un juego educativo enfocado a aprender sobre algunos conceptos que se tratan en los grados de ingeniería informática, telemática y sistemas audiovisuales de la Universidad Pompeu Fabra (UPF). En concreto, el juego que se ha diseñado e implementado se caracteriza por seguir un modelo conceptual que define qué elementos han de contener un tipo concreto de juegos basados en puzles. Además, aprovechando las ventajas que aportan los estándares educativos, utilizaremos la especificación de IMS Learning Design, como parte de la implementación del juego. Por otro lado, nuestro juego será diseñado para dispositivos móviles y, por consiguiente, consistirá en un juego pervasivo en el que los estudiantes se tendrán que mover por el edificio Tànger de la UPF para poder resolver los diferentes problemas planteados. Finalmente, el juego será evaluado con diferentes estudiantes y serán analizados sus resultados para extraer las conclusiones oportunas.
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El aprendizaje basado en juegos proporciona a los alumnos una forma de aprender más motivadora y gratificante al estudiante. Los juegos educativos permiten a los estudiantes centrarse completamente en un contenido concreto, resultándoles beneficioso a la hora de profundizar su conocimiento en esa materia. Esta forma de educar puede ayudar a revertir la situación actual de desinterés de los alumnos por las asignaturas del área de las ingenierías de las Tecnologías de la Información y la Comunicación (TIC). En este sentido, estudios realizados y estadísticas demuestran que las matriculaciones en este sector han disminuido en los últimos años. Teniendo en cuenta estos factores, en este PFC se ha diseñado un juego educativo, basado en puzzles, para aprender conceptos relacionados con las redes de ordenadores, una de las temáticas principales en el campo de las ingenierías TIC. El diseño del juego está fundamentado en un modelo conceptual que define los elementos necesarios para crear juegos basados en puzzles. Por otra parte, en este PFC se hace uso de estándares educativos (en concreto, de la especificación de IMS Learning Design), para la implementación del juego. De este modo, el juego se beneficia de las ventajas derivadas del uso de estándares educativos: definición, compartición y reutilización de objetos de aprendizaje para el diseño, intercambio y la reutilización de estrategias pedagógicas, facilitando la interoperabilidad de los diseños pedagógicos complejos. Además, el juego se ha implementado con tecnología para Android,pudiendo de esta manera ser utilizado en dispositivos móviles que utilicen esta tecnología. Por último, nuestro juego ha sido evaluado por estudiantes de un centro escolar con el fin de analizar los resultados obtenidos a partir de sus opiniones y valoraciones.