938 resultados para Comparative studies
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This dissertation develops and tests a comparative effectiveness methodology utilizing a novel approach to the application of Data Envelopment Analysis (DEA) in health studies. The concept of performance tiers (PerT) is introduced as terminology to express a relative risk class for individuals within a peer group and the PerT calculation is implemented with operations research (DEA) and spatial algorithms. The analysis results in the discrimination of the individual data observations into a relative risk classification by the DEA-PerT methodology. The performance of two distance measures, kNN (k-nearest neighbor) and Mahalanobis, was subsequently tested to classify new entrants into the appropriate tier. The methods were applied to subject data for the 14 year old cohort in the Project HeartBeat! study.^ The concepts presented herein represent a paradigm shift in the potential for public health applications to identify and respond to individual health status. The resultant classification scheme provides descriptive, and potentially prescriptive, guidance to assess and implement treatments and strategies to improve the delivery and performance of health systems. ^
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Birth defects are the leading cause of infant mortality in the United States and are a major cause of lifetime disability. However, efforts to understand their causes have been hampered by a lack of population-specific data. During 1990–2004, 22 state legislatures responded to this need by proposing birth defects surveillance legislation (BDSL). The contrast between these states and those that did not pass BDSL provides an opportunity to better understand conditions associated with US public health policy diffusion. ^ This study identifies key state-specific determinants that predict: (1) the introduction of birth defects surveillance legislation (BDSL) onto states' formal legislative agenda, and (2) the successful adoption of these laws. Secondary aims were to interpret these findings in a theoretically sound framework and to incorporate evidence from three analytical approaches. ^ The study begins with a comparative case study of Texas and Oregon (states with divergent BDSL outcomes), including a review of historical documentation and content analysis of key informant interviews. After selecting and operationalizing explanatory variables suggested by the case study, Qualitative Comparative Analysis (QCA) was applied to publically available data to describe important patterns of variation among 37 states. Results from logistic regression were compared to determine whether the two methods produced consistent findings. ^ Themes emerging from the comparative case study included differing budgetary conditions and the significance of relationships within policy issue networks. However, the QCA and statistical analysis pointed to the importance of political parties and contrasting societal contexts. Notably, state policies that allow greater access to citizen-driven ballot initiatives were consistently associated with lower likelihood of introducing BDSL. ^ Methodologically, these results indicate that a case study approach, while important for eliciting valuable context-specific detail, may fail to detect the influence of overarching, systemic variables, such as party competition. However, QCA and statistical analyses were limited by a lack of existing data to operationalize policy issue networks, and thus may have downplayed the impact of personal interactions. ^ This study contributes to the field of health policy studies in three ways. First, it emphasizes the importance of collegial and consistent relationships among policy issue network members. Second, it calls attention to political party systems in predicting policy outcomes. Finally, a novel approach to interpreting state data in a theoretically significant manner (QCA) has been demonstrated.^
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This study assessed and compared sociodemographic and income characteristics along with food and physical activity assets (i.e. grocery stores, fast food restaurants, and park areas) in the Texas Childhood Obesity Research Demonstration (CORD) Study intervention and comparison catchment areas in Houston and Austin, Texas. The Texas CORD Study used a quasi-experimental study design, so it is necessary to establish the interval validity of the study characteristics by confirming that the intervention and comparison catchment areas are statistically comparable. In this ecological study, ArcGIS and Esri Business Analyst were used to spatially relate U.S. Census Bureau and other business listing data to the specific school attendance zones within the catchment areas. T-tests were used to compare percentages of sociodemographic and income characteristics and densities of food and physical activity assets between the intervention and comparison catchment areas.^ Only five variables were found to have significant differences between the intervention and comparison catchment areas: Age groups 0-4 and 35-64, the percentage of owner-occupied and renter-occupied households, and the percentage of Asian and Pacific Islander residents. All other variables showed no significant differences between the two groups. This study shows that the methodology used to select intervention and comparison catchment areas for the Texas CORD Study was effective and can be used in future studies. The results of this study can be used in future Texas CORD studies to confirm the comparability of the intervention and comparison catchment areas. In addition, this study demonstrates a methodology for describing detailed characteristics about a geographic area that practitioners, researchers, and educators can use.^
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This paper empirically examines the different comparative advantages of two emerging economic giants, China and India, in relation to the different skill distribution patterns in each country. By utilizing industry export data on China and India from 1983 to 2000, we find that a country with a greater dispersion of skills (i.e., India, especially in the earlier years) has higher exports in industries with shorter production chains, whereas a country with a more equal dispersion of skills (i.e., China, especially in the later years) is found to have higher exports in industries with longer production chains. The causal relationship is fairly robust across different specifications. This empirical evidence supports our assumption that the likely mechanism for these results is the negative impact of low-skilled workers on input quality, which accumulates and becomes larger as the length of production chains and the proportion of low-skilled workers in the economy increase.
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Water development accompanying mankind development has turned rivers into endangered ecosystems. Improving the understanding of ecological responses to river management actions is a key issue for assuring sustainable water management. However, few studies have been published where ecological metrics have been quantified in response to various degrees of flow alteration. In this work, changes in natural distribution of trees and shrubs within the riparian corridor (as indicator of the ecological status of the fluvial ecosystem) were quantified at multiple sites along a flow alteration gradient (as indicator of impact) along two regulated river reaches, one Boreal and the other Mediterranean, each downstream of a dam. Based on the obtained relationships we evaluated differences in response trends related to local physico-climatic factors of the two biomes and regarding to differing life-forms. Woody vegetation establishment patterns represented objective indicators of ecological responses to flow alteration. We found different responses between life-forms. Both trees and shrubs migrated downwards to the channel after dam closure, but shrubs were most impacted under higher degrees of flow alteration in terms of lateral movement. In addition, our results show clear longitudinal recovery trends of natural patterns of tree and shrub distribution corresponding to a decrease in intensity of hydrologic alteration in the Boreal river. However, vegetation encroachment persisted along the entire Mediterranean study reach. This may result from a relatively low gradient of decrease of hydrologic alteration with distance from the dam, coupled with other overlapping pressures and the mediating effect of physico-climatic characteristics on vegetation responses.
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European Universities are involved in series of great changes regarding teaching and education organization during the last few years. The origin of these changes is the creation of the so-called European Higher Education Area (EHEA), which main target is to harmonize the different University studies throughout Europe. As a consequence, most of the programs of studies in all degrees are suffering changes in order to converge to common structures. Taking advantage of the actual process, some European universities are moving from traditional Agricultural Engineering programs to a more wide discipline named recently as Biosystems Engineering, which is a science- based engineering discipline that integrates engineering science and design with applied biological, environmental and agricultural sciences, broadening in this way the area of application of Engineering sciences not strictly to agricultural sciences, but to the biologic al sciences in general, including the agricultural sciences. This paper presents a comparative study of different Bachelor of Science degrees offered by American and European Universities in the field of Agricultural/Biosystems Engineering. To carry out the analysis 40 programs accredited by ABET in American Universities and 50 European programs. Among other questions, the total number of credits, the number of semesters, the kind of modules and the distribution of subjects in groups (Basic Sciences, Engineering Fundamentals, Agricultural/Biological Sciences, Humanities & Economic Sciences, Applied Agricultural/Biological Engineering and electives) are discussed in the paper. The information provided can be an useful starting point in future definitions of new or renewed degrees with the aim of advancing in internationalization of the programs and helping student’s mobility.
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International Comparative Medicine Symposium. Allergology. Revisión de métodos computacionales para determinar propiedades de alergenos alimentarios de plantas
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Esta tesis doctoral, que es la culminación de mis estudios de doctorado impartidos por el Departamento de Lingüística Aplicada a la Ciencia y a la Tecnología de la Universidad Politécnica de Madrid, aborda el análisis del uso de la matización (hedging) en el lenguaje legal inglés siguiendo los postulados y principios de la análisis crítica de género (Bhatia, 2004) y empleando las herramientas de análisis de córpora WordSmith Tools versión 6 (Scott, 2014). Como refleja el título, el estudio se centra en la descripción y en el análisis contrastivo de las variedades léxico-sintácticas de los matizadores del discurso (hedges) y las estrategias discursivas que con ellos se llevan a cabo, además de las funciones que éstas desempeñan en un corpus de sentencias del Tribunal Supremo de EE. UU., y de artículos jurídicos de investigación americanos, relacionando, en la medida posible, éstas con los rasgos determinantes de los dos géneros, desde una perspectiva socio-cognitiva. El elemento innovador que ofrece es que, a pesar de los numerosos estudios que se han podido realizar sobre los matizadores del discurso en el inglés general (Lakoff, 1973; Hübler, 1983; Clemen, 1997; Markkanen and Schröder, 1997; Mauranen, 1997; Fetzer 2010; y Finnegan, 2010 entre otros) académico (Crompton, 1997; Meyer, 1997; Skelton, 1997; Martín Butragueňo, 2003) científico (Hyland, 1996a, 1996c, 1998c, 2007; Grabe and Kaplan, 1997; Salager-Meyer, 1997 Varttala, 2001) médico (Prince, 1982; Salager-Meyer, 1994; Skelton, 1997), y, en menor medida el inglés legal (Toska, 2012), no existe ningún tipo de investigación que vincule los distintos usos de la matización a las características genéricas de las comunicaciones profesionales. Dentro del lenguaje legal, la matización confirma su dependencia tanto de las expectativas a macro-nivel de la comunidad de discurso, como de las intenciones a micro-nivel del escritor de la comunicación, variando en función de los propósitos comunicativos del género ya sean éstos educativos, pedagógicos, interpersonales u operativos. El estudio pone de relieve el uso predominante de los verbos modales epistémicos y de los verbos léxicos como matizadores del discurso, estos últimos divididos en cuatro tipos (Hyland 1998c; Palmer 1986, 1990, 2001) especulativos, citativos, deductivos y sensoriales. La realización léxico-sintáctica del matizador puede señalar una de cuatro estrategias discursivas particulares (Namsaraev, 1997; Salager-Meyer, 1994), la indeterminación, la despersonalización, la subjectivisación, o la matización camuflada (camouflage hedging), cuya incidencia y función varia según género. La identificación y cuantificación de los distintos matizadores y estrategias empleados en los diferentes géneros del discurso legal puede tener implicaciones pedagógicos para los estudiantes de derecho no nativos que tienen que demostrar una competencia adecuada en su uso y procesamiento. ABSTRACT This doctoral thesis, which represents the culmination of my doctoral studies undertaken in the Department of Linguistics Applied to Science and Technology of the Universidad Politécnica de Madrid, focusses on the analysis of hedging in legal English following the principles of Critical Genre Analysis (Bhatia, 2004), and using WordSmith Tools version 6 (Scott, 2014) corpus analysis tools. As the title suggests, this study centers on the description and contrastive analysis of lexico-grammatical realizations of hedges and the discourse strategies which they can indicate, as well as the functions they can carry out, in a corpus of U.S. Supreme Court opinions and American law review articles. The study relates realization, incidence and function of hedging to the predominant generic characteristics of the two genres from a socio-cognitive perspective. While there have been numerous studies on hedging in general English (Lakoff, 1973; Hübler, 1983; Clemen, 1997; Markkanen and Schröder, 1997; Mauranen, 1997; Fetzer 2010; and Finnegan, 2010 among others) academic English (Crompton, 1997; Meyer, 1997; Skelton, 1997; Martín Butragueňo, 2003) scientific English (Hyland, 1996a, 1996c, 1998c, 2007; Grabe and Kaplan, 1997; Salager-Meyer, 1997 Varttala, 2001) medical English (Prince, 1982; Salager-Meyer, 1994; Skelton, 1997), and, to a lesser degree, legal English (Toska, 2012), this study is innovative in that it links the different realizations and functions of hedging to the generic characteristics of a particular professional communication. Within legal English, hedging has been found to depend on not only the macro-level expectations of the discourse community for a specific genre, but also on the micro-level intentions of the author of a communication, varying according to the educational, pedagogical, interpersonal or operative purposes the genre may have. The study highlights the predominance of epistemic modal verbs and lexical verbs as hedges, dividing the latter into four types (Hyland, 1998c; Palmer, 1986, 1990, 2001): speculative, quotative, deductive and sensorial. Lexical-grammatical realizations of hedges can signal one of four discourse strategies (Namsaraev, 1997; Salager-Meyer, 1994), indetermination, depersonalization, subjectivization and camouflage hedging, as well as fulfill a variety of functions. The identification and quantification of the different hedges and hedging strategies and functions in the two genres may have pedagogical implications for non-native law students who must demonstrate adequate competence in the production and interpretation of hedged discourse.
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The construction industry produces great environmental impacts to the planet. In order to tackle this problem, the European Union has put into effect Regulation No 305/2011, which compels the construction products manufacturers to carry out environmental performance studies of these products and thus make public the impact they cause on the environment. The aim of this research is to make known the environmental impacts of the SOS Natura Conventional Façade (CF) solution, obtained within the research project "SOS Natura, Vegetal Architectural Solutions" developed by the Department of Construction and Technology in Architecture of the School of Architecture of the Technical University of Madrid (Spain). In addition, we report an environmental comparative with the Natural Water Tank Façade (NWTF), studied previously by the same work group and included in the same research project.We present as well an uncertainty analysis for both façades. Following the study conducted we conclude that the NWTF profile has a slightly better environmental behaviour when compared to the CF profile for the entire life cycle in most of the impact categories analysed in this study. However it should also be noted that, in detail and at stage level, the NWTF presents a higher environmental impact than the CF.
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Human immunodeficiency virus type 1 (HIV-1) and human T cell leukemia virus type II (HTLV-2) use a similar mechanism for –1 translational frameshifting to overcome the termination codon in viral RNA at the end of the gag gene. Previous studies have identified two important RNA signals for frameshifting, the slippery sequence and a downstream stem–loop structure. However, there have been somewhat conflicting reports concerning the individual contributions of these sequences. In this study we have performed a comprehensive mutational analysis of the cis-acting RNA sequences involved in HIV-1 gag–pol and HTLV-2 gag–pro frameshifting. Using an in vitro translation system we determined frameshifting efficiencies for shuffled HIV-1/HTLV-2 RNA elements in a background of HIV-1 or HTLV-2 sequences. We show that the ability of the slippery sequence and stem–loop to promote ribosomal frameshifting is influenced by the flanking upstream sequence and the nucleotides in the spacer element. A wide range of frameshift efficiency rates was observed for both viruses when shuffling single sequence elements. The results for HIV-1/HTLV-2 chimeric constructs represent strong evidence supporting the notion that the viral wild-type sequences are not designed for maximal frameshifting activity but are optimized to a level suited to efficient viral replication.
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Chromosome 7q22 has been the focus of many cytogenetic and molecular studies aimed at delineating regions commonly deleted in myeloid leukemias and myelodysplastic syndromes. We have compared a gene-dense, GC-rich sub-region of 7q22 with the orthologous region on mouse chromosome 5. A physical map of 640 kb of genomic DNA from mouse chromosome 5 was derived from a series of overlapping bacterial artificial chromosomes. A 296 kb segment from the physical map, spanning Ache to Tfr2, was compared with 267 kb of human sequence. We identified a conserved linkage of 12 genes including an open reading frame flanked by Ache and Asr2, a novel cation-chloride cotransporter interacting protein Cip1, Ephb4, Zan and Perq1. While some of these genes have been previously described, in each case we present new data derived from our comparative sequence analysis. Adjacent unfinished sequence data from the mouse contains an orthologous block of 10 additional genes including three novel cDNA sequences that we subsequently mapped to human 7q22. Methods for displaying comparative genomic information, including unfinished sequence data, are becoming increasingly important. We supplement our printed comparative analysis with a new, Web-based program called Laj (local alignments with java). Laj provides interactive access to archived pairwise sequence alignments via the WWW. It displays synchronized views of a dot-plot, a percent identity plot, a nucleotide-level local alignment and a variety of relevant annotations. Our mouse–human comparison can be viewed at http://web.uvic.ca/~bioweb/laj.html. Laj is available at http://bio.cse.psu.edu/, along with online documentation and additional examples of annotated genomic regions.
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Nearly all metazoan homeodomains (HDs) possess DNA binding targets that are related by the presence of a TAAT sequence. We use an in vitro genetic DNA binding site selection assay to refine our understanding of the amino acid determinants for the recognition of the TAAT site. Superimposed upon the conserved ability of metazoan HDs to recognize a TAAT core is a difference in their preference for the bases that lie immediately 3' to it. Amino acid position 50 of the HD has been shown to discriminate among these base pairs, and structural studies have suggested that water-mediated hydrogen bonds and van der Waals contacts underlie for this ability. Here, we show that each of six amino acids tested at position 50 can confer a distinct DNA binding specificity.
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The structure and function relationship between melanocortin-2 receptor (MC2R) and ACTH are the most complicated in melanocortin receptor gene family. A comparative study on the activation of human and rainbow trout MC2R will provide a useful model system for understanding how ACTH emerged as the sole ligand for the MC2R of bony vertebrates. This dissertation will discuss how studies utilizing analogs of hACTH(1-24) have revealed two critical amino acid motifs in this ligand (HFRW and KKRRP) which are required for the activation of MC2R. In addition, the KKRRP motif functioned as the unique binding site for MC2R that directly contributes to the ligand selectivity feature, as revealed from studies on an ACTH antagonist which exclusively targets MC2R. Finally, based on our model for the interaction of ACTH and MC2R, the amino acid residues within TM4, EC2, and TM5 domains responsible for ACTH ligand selectivity will be evaluated by site-directed mutagenesis studies.
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Urban parks have long been valued for the environmental, social, and economic benefits they provide. Increasingly, parks are also being recognized as features important for sustainable city design. This Capstone Project will identify, compare, analyze, and discuss means for designing sustainable urban parks. Recommendations for designing sustainable urban parks, based on project results, include: 1) ensure park features will support high levels of human activity; 2) use gravel to construct park trails; 3) purchase playground structures made of recycled materials; 4) plant a high number of perennials in flowerbeds and other vegetated areas; 5) plant climate-appropriate plants in vegetated areas; 6) ensure parks have high levels of plant diversity; and 7) develop future studies further exploring sustainable park design.
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Background: The aim was to evaluate the visual performance achieved with a new multifocal hybrid contact lens and to compare it with that obtained with two other currently available multifocal soft contact lenses. Methods: This pilot prospective comparative study comprised a total of 16 presbyopic eyes of eight patients ranging in age from 43 to 58 years. All patients were fitted with three different models of multifocal contact lens: Duette multifocal (SynergEyes), Air Optix AQUA multifocal (Alcon) and Biofinity multifocal (CooperVision). Fittings were performed randomly in each patient according to a random number sequence, with a wash-out period between fittings of seven days. At two weeks post-fitting, visual, photopic contrast sensitivity and ocular aberrometry were evaluated. Results: No statistically significant differences were found in distance and near visual acuity achieved with the three different types of multifocal contact lens (p ≥ 0.05). Likewise, no significant differences between lenses were found in the monocular and binocular defocus curve (p ≥ 0.10). Concerning contrast sensitivity, better monocular contrast sensitivities for 6, 12 and 18 cycles per degree were found with the Duette and Air Optix multifocal compared to Biofinity (p = 0.02). Binocularly, differences between lenses were not significant (p ≥ 0.27). Furthermore, trefoil aberration was significantly higher with Biofinity multifocal (p < 0.01) and Air Optix (p = 0.01) multifocal compared to Duette. Conclusions: The Duette multifocal hybrid contact lens seems to provide similar visual quality outcomes in presbyopic patients with low corneal astigmatism, when compared with other soft multifocal contact lenses. This preliminary result should be confirmed in studies with larger samples.