960 resultados para Sample studies
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Purpose. To analyze dry eye disease (DED) tests and their consistency in similar nonsymptomatic population samples living in two geographic locations with different climates (Continental vs. Atlantic). Methods. This is a pilot study including 14 nonsymptomatic residents from Valladolid (Continental climate, Spain) and 14 sex-matched and similarly aged residents from Braga (Atlantic climate, Portugal); they were assessed during the same season (spring) of two consecutive years. Phenol red thread test, conjunctival hyperemia, fluorescein tear breakup time, corneal and conjunctival staining, and Schirmer test were evaluated on three different consecutive visits. Reliability was assessed using the intraclass correlation coefficient and weighted kappa (J) coefficient for quantitative and ordinal variables, respectively. Results. Fourteen subjects were recruited in each city with a mean (TSD) age of 63.0 (T1.7) and 59.1 (T0.9) years (p = 0.08) in Valladolid and Braga, respectively. Intraclass correlation coefficient and J values of the tests performed were below 0.69 and 0.61, respectively, for both samples, thus showing moderate to poor reliability. Subsequently, comparisons were made between the results corresponding to the middle and higher outdoor relative humidity (RH) visit in each location as there were no differences in mean temperature (p Q 0.75) despite RH values significantly differing (p e 0.005). Significant (p e 0.05) differences were observed between Valladolid and Braga samples on tear breakup time (middle RH visit, 2.76 T 0.60 vs. 5.26 T 0.64 seconds; higher RH visit, 2.61 T 0.32 vs. 5.78 T 0.88 seconds) and corneal (middle RH, 0.64 T 0.17 vs. 0.14 T 0.10; higher RH, 0.60 T 0.22 vs. 0.0 T 0.0) and conjunctival staining (middle RH, 0.61 T 0.17 vs. 0.14 T 0.08; higher RH, 0.57 T 0.15 vs. 0.18 T 0.09). Conclusions. This pilot study provides initial evidence to support that DED test outcomes assessing the ocular surface integrity and tear stability are climate dependent. Future large-sample studies should support these outcomes also in DED patients. This knowledge is fundamental for multicenter clinical trials. Lack of consistency in diagnostic clinical tests for DED was also corroborated. (Optom Vis Sci 2015;92:e284Ye289)
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Purpose: Surgery remains the treatment of choice for localized renal neoplasms. While radical nephrectomy was long considered the gold standard, partial nephrectomy has equivalent oncological results for small tumors. The role of negative surgical margins continues to be debated. Intraoperative frozen section analysis is expensive and time-consuming. We assessed the feasibility of intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy and its correlation with margin status on definitive pathological evaluation.Materials and Methods: A study was done at 2 institutions from February 2008 to March 2011. Patients undergoing partial nephrectomy for T1-T2 renal tumors were included in analysis. Partial nephrectomy was done by a standardized minimal healthy tissue margin technique. After resection the specimen was kept in saline and tumor margin status was immediately determined by ex vivo ultrasound. Sequential images were obtained to evaluate the whole tumor pseudocapsule. Results were compared with margin status on definitive pathological evaluation.Results: A total of 19 men and 14 women with a mean +/- SD age of 62 +/- 11 years were included in analysis. Intraoperative ex vivo ultrasound revealed negative surgical margins in 30 cases and positive margins in 2 while it could not be done in 1. Final pathological results revealed negative margins in all except 1 case. Ultrasound sensitivity and specificity were 100% and 97%, respectively. Median ultrasound duration was 1 minute. Mean tumor and margin size was 3.6 +/- 2.2 cm and 1.5 +/- 0.7 mm, respectively.Conclusions: Intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy is feasible and efficient. Large sample studies are needed to confirm its promising accuracy to determine margin status.
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The recent behavior of the Brazilian direct investment abroad in perspective. This paper analyzes the recent behavior of the Brazilian direct investment abroad, as captured by an annual census conducted by the Central Bank of Brazil since 2001, by putting it in a broader perspective that includes international official data sources and early sample studies. Though the Central Bank has not been making available more disaggregated data than those analyzed here, it is intended to contribute to a better grasping of the perspectives of competitive internationalization of local firms, which is desirable not only as far as the external accounts are concerned, but also from the viewpoint of the technological capabilities of the local firms.
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In den letzten Jahrzehnten haben sich makroskalige hydrologische Modelle als wichtige Werkzeuge etabliert um den Zustand der globalen erneuerbaren Süßwasserressourcen flächendeckend bewerten können. Sie werden heutzutage eingesetzt um eine große Bandbreite wissenschaftlicher Fragestellungen zu beantworten, insbesondere hinsichtlich der Auswirkungen anthropogener Einflüsse auf das natürliche Abflussregime oder der Auswirkungen des globalen Wandels und Klimawandels auf die Ressource Wasser. Diese Auswirkungen lassen sich durch verschiedenste wasserbezogene Kenngrößen abschätzen, wie z.B. erneuerbare (Grund-)Wasserressourcen, Hochwasserrisiko, Dürren, Wasserstress und Wasserknappheit. Die Weiterentwicklung makroskaliger hydrologischer Modelle wurde insbesondere durch stetig steigende Rechenkapazitäten begünstigt, aber auch durch die zunehmende Verfügbarkeit von Fernerkundungsdaten und abgeleiteten Datenprodukten, die genutzt werden können, um die Modelle anzutreiben und zu verbessern. Wie alle makro- bis globalskaligen Modellierungsansätze unterliegen makroskalige hydrologische Simulationen erheblichen Unsicherheiten, die (i) auf räumliche Eingabedatensätze, wie z.B. meteorologische Größen oder Landoberflächenparameter, und (ii) im Besonderen auf die (oftmals) vereinfachte Abbildung physikalischer Prozesse im Modell zurückzuführen sind. Angesichts dieser Unsicherheiten ist es unabdingbar, die tatsächliche Anwendbarkeit und Prognosefähigkeit der Modelle unter diversen klimatischen und physiographischen Bedingungen zu überprüfen. Bisher wurden die meisten Evaluierungsstudien jedoch lediglich in wenigen, großen Flusseinzugsgebieten durchgeführt oder fokussierten auf kontinentalen Wasserflüssen. Dies steht im Kontrast zu vielen Anwendungsstudien, deren Analysen und Aussagen auf simulierten Zustandsgrößen und Flüssen in deutlich feinerer räumlicher Auflösung (Gridzelle) basieren. Den Kern der Dissertation bildet eine umfangreiche Evaluierung der generellen Anwendbarkeit des globalen hydrologischen Modells WaterGAP3 für die Simulation von monatlichen Abflussregimen und Niedrig- und Hochwasserabflüssen auf Basis von mehr als 2400 Durchflussmessreihen für den Zeitraum 1958-2010. Die betrachteten Flusseinzugsgebiete repräsentieren ein breites Spektrum klimatischer und physiographischer Bedingungen, die Einzugsgebietsgröße reicht von 3000 bis zu mehreren Millionen Quadratkilometern. Die Modellevaluierung hat dabei zwei Zielsetzungen: Erstens soll die erzielte Modellgüte als Bezugswert dienen gegen den jegliche weiteren Modellverbesserungen verglichen werden können. Zweitens soll eine Methode zur diagnostischen Modellevaluierung entwickelt und getestet werden, die eindeutige Ansatzpunkte zur Modellverbesserung aufzeigen soll, falls die Modellgüte unzureichend ist. Hierzu werden komplementäre Modellgütemaße mit neun Gebietsparametern verknüpft, welche die klimatischen und physiographischen Bedingungen sowie den Grad anthropogener Beeinflussung in den einzelnen Einzugsgebieten quantifizieren. WaterGAP3 erzielt eine mittlere bis hohe Modellgüte für die Simulation von sowohl monatlichen Abflussregimen als auch Niedrig- und Hochwasserabflüssen, jedoch sind für alle betrachteten Modellgütemaße deutliche räumliche Muster erkennbar. Von den neun betrachteten Gebietseigenschaften weisen insbesondere der Ariditätsgrad und die mittlere Gebietsneigung einen starken Einfluss auf die Modellgüte auf. Das Modell tendiert zur Überschätzung des jährlichen Abflussvolumens mit steigender Aridität. Dieses Verhalten ist charakteristisch für makroskalige hydrologische Modelle und ist auf die unzureichende Abbildung von Prozessen der Abflussbildung und –konzentration in wasserlimitierten Gebieten zurückzuführen. In steilen Einzugsgebieten wird eine geringe Modellgüte hinsichtlich der Abbildung von monatlicher Abflussvariabilität und zeitlicher Dynamik festgestellt, die sich auch in der Güte der Niedrig- und Hochwassersimulation widerspiegelt. Diese Beobachtung weist auf notwendige Modellverbesserungen in Bezug auf (i) die Aufteilung des Gesamtabflusses in schnelle und verzögerte Abflusskomponente und (ii) die Berechnung der Fließgeschwindigkeit im Gerinne hin. Die im Rahmen der Dissertation entwickelte Methode zur diagnostischen Modellevaluierung durch Verknüpfung von komplementären Modellgütemaßen und Einzugsgebietseigenschaften wurde exemplarisch am Beispiel des WaterGAP3 Modells erprobt. Die Methode hat sich als effizientes Werkzeug erwiesen, um räumliche Muster in der Modellgüte zu erklären und Defizite in der Modellstruktur zu identifizieren. Die entwickelte Methode ist generell für jedes hydrologische Modell anwendbar. Sie ist jedoch insbesondere für makroskalige Modelle und multi-basin Studien relevant, da sie das Fehlen von feldspezifischen Kenntnissen und gezielten Messkampagnen, auf die üblicherweise in der Einzugsgebietsmodellierung zurückgegriffen wird, teilweise ausgleichen kann.
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Os levantamentos epidemiológicos são importantes para o conhecimento da prevalência e tipologia das doenças bucais, podendo-se a partir dos dados coletados, planejar, executar e avaliar ações de saúde. É necessário, no entanto, que haja rigor metodológico que garanta reprodutibilidade, validade e confiabilidade, e que haja uniformidade de procedimentos para permitir comparações nacionais e internacionais. A iniciativa da Organização Mundial da Saúde (OMS) na assessoria à realização de levantamentos tem se mostrado extremamente útil, estimulando o estabelecimento de padrões de procedimentos que podem ser utilizados em todos os países. em 1991 foi publicada a edição em português da terceira edição do Oral Health Surveys - basic methods, de 1987, um manual que objetiva fornecer instruções para a realização de levantamentos epidemiológicos e tal publicação passou a servir de base a estudos realizados em diversos locais do Brasil e do mundo. O objetivo deste trabalho, é analisar criticamente a metodologia para Levantamento Epidemiológico em Saúde Bucal da OMS, na tentativa de contribuir para o aperfeiçoamento da mesma. de acordo com a presente análise, foram encontrados pontos relevantes para consideração, referentes à amostragem, à calibração dos examinadores e aos critérios para a avaliação de saúde bucal e necessidades de tratamento. Concluiu-se, em nível de recomendação, que, devido ao caráter dinâmico do conhecimento científico e, levando-se em consideração as diferenças regionais com relação ao padrão de desenvolvimento das doenças bucais, as propostas de padronização de levantamentos devem ser periodicamente revisadas. É provável, ainda, que outros pontos importantes não tenham sido detectados nesta análise, tornando-se premente ampliar esta discussão para toda a comunidade odontológica.
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Pós-graduação em Ciências da Motricidade - IBRC
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Animal coloration often serves as a signal to others that may communicate traits about the individual such as toxicity, status, or quality. Colorful ornaments in many animals are often honest signals of quality assessed by mates, and different colors may beproduced by different biochemical pigments. Investigations of the mechanisms responsible for variation in color expression among birds are best when including a geographically and temporally broad sample. In order to obtain such a sample, studies such as this often use museum specimens; however, in order for museum specimens toserve as an accurate replacement, they must accurately represent living birds, or we must understand the ways in which they differ. In this thesis, I investigated the link between feather corticosterone, a hormone secreted in response to stress, and carotenoid-basedcoloration in the Red-winged Blackbird (Agelaius phoeniceus) in order to explore a mechanistic link between physiological state and color expression. Male Red-winged Blackbirds with lower feather corticosterone had significantly brighter red epaulets than birds with higher feather corticosterone, while I found no significant changes in red chroma. I also performed a methodological comparison of color change in museum specimens among different pigment types (carotenoid and psittacofulvin) and pigments in different locations in the body (feather and bill carotenoids) in order to quantify colorchange over time. Carotenoids and psittacofulvins showed significant reductions in red brightness and chroma over time in the collection, and carotenoid color changed significantly faster than psittacofulvin color. Both bill and feather carotenoids showed significant reductions in red brightness and red chroma over time, but change of both red chroma and red brightness occurred at a similar rate in feathers and bills. In order to use museum specimens of ecological research on bird coloration specimen age must be accounted for before the data can be used; however, once this is accomplished, museum- based color data may be used to draw conclusions about wild populations.
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Although posttraumatic stress disorder (PTSD) is associated with a variety of structural and functional brain changes, the molecular pathophysiological mechanisms underlying these macroscopic alterations are unknown. Recent studies support the existence of an altered excitation-inhibition balance in PTSD. Further, there is preliminary evidence from blood-sample studies suggesting heightened oxidative stress in PTSD, potentially leading to neural damage through excessive brain levels of free radicals. In this study we investigated PTSD (n=12) and non-PTSD participants (n=17) using single-voxel proton magnetic resonance spectroscopy (MRS) in dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC). We found significantly higher levels of γ-amino butyric acid (GABA) (a primary inhibitory neurotransmitter) and glutathione (a marker for neuronal oxidative stress) in PTSD participants. Atypically high prefrontal inhibition as well as oxidative stress may be involved in the pathogenesis of PTSD.
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Siliceous sediments and sedimentary rocks occur as chert and silicified chalk, limestone, and claystone in Site 585 lower Miocene to Campanian sediments, with one older occurrence of chert near the Cenomanian/Turonian boundary. The recovered drill breccia in the Miocene to middle Eocene interval is dominated by bright red, orange, yellow, and brown chips and fragments of chert. In early Eocene and older sediments gray silicified limestone and yellowish brown chert fragments predominate. Recovery is poor in cores with chert because chert tends to fracture into smaller pieces that escape the drill and because the hard chert fragments grind away other sediments during rotary drilling. Thin-section and hand-sample studies show complex diagenetic histories of silicification (silica pore infill) and chertification (silica replacement of host rock). Multiple events of silicification can occur in the same rocks, producing chert from silicified limestone. Despite some prior silicification, silicified limestone is porous enough to provide conduits for dissolved silica-charged pore waters. Silicification and chert are more abundant in the coarser parts of the sedimentary section. These factors reflect the importance of porosity and permeability as well as chemical and lithologic controls in the process of silica diagenesis.
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A műhelytanulmány célja, hogy megalapozzon egy, a lean menedzsment és a szervezeti kultúra kapcsolatát vizsgáló empirikus kutatást. Máig ritka a szűken vett témában született publikációk száma, ezért tanulmányunkban olyan forrásokat dolgozunk fel, amelyek a lean menedzsmenten túl a termelésmenedzsment más koncepcióit, gyakorlatait (minőségmenedzsment és a fejlett termelési rendszerek), az általuk elérhető teljesítmény és a szervezeti kultúra kapcsolatát értelmezi, vagy vizsgálja. A források módszeres áttekintésével azonosítjuk a kutatásokat indokoló tényezőket, az érintett termelésmenedzsment koncepciók értelmezéseit, a szervezeti kultúra értelmezéséket és a kutatási eredményeket. Mindezek alapján bemutatjuk, hogy melyek lehetnek azok a kérdések, melyek egy, a szervezeti kultúra és a lean menedzsment kapcsolatát vizsgáló empirikus kutatás során figyelmet érdemelnek. Bemutatjuk továbbá, hogy milyen egyéb tényezőkre kell figyelemmel lenni egy ilyen kutatás tervezése során. Önmagában a lean menedzsment, mint téma újszerű a szervezeti kultúrával kapcsolatos kutatások területén. Ezen túl a nagymintás és az angolszász területeken kívül eső kutatások kecsegtetnek jelentős új ismerettel. További újdonságot jelente a termelésmenedzsment koncepció és a szervezeti kultúra kapcsolatának megragadásán túl a kapcsolat természetének (a hatás irányának) feltárása. ______ The aim of this paper is to provide a solid base for a study that would examine the relationship between lean management and organizational culture. Since there are only limited number of publications in this topic, in our study we examined publications, which interpreted or examined the relationship among organizational culture, organizational performance and - beyond lean management - any operations management concepts or practices (but mainly quality management and advanced manufacturing technologies). Rigorously reviewing the selected sources, we identified the main questions justifying the researches, interpretations of the involved operations management concepts, interpretations of organization culture, and research results. Based on our review, we highlight those questions that are worth to examine within a research targeting to study the relationship between the organizational culture and lean management. Moreover, we identified other important factors to be considered when designing such research. Lean management by itself a novelty in the research field related to organizational culture. Moreover, large sample studies conducted outside the Anglo-Saxon territory likely to bring notable novelty. Further new knowledge may emerge if beyond capturing the existence of relationship among organizational culture and any operations management concept the nature of the relationship (the direction of the influence) was also investigated.
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Epidemiological surveys are important for obtaining information on the prevalence and etiology of mouth diseases, since the data collected permit health actions to be planned, performed, and assessed. Methodological uniformity is necessary, however, to maintain reproductibility, validity, and reliability, and to allow national and international comparisons. The initiative of the World Health Organization (WHO) as an advisor in ongoing surveys has been extremely useful, stimulating standardization in all countries. In 1991, a Portuguese version of the 1987 third edition of Oral Health Surveys - basic methods, an instruction manual for performing epidemiological surveys, was published and became a reference for many parts of Brazil and the World. The present analysis found conflicting points in relation to the sample size, calibration of the examiners, and criteria for evaluating oral health and treatment needs. In conclusion, due to the dynamic characteristics of scientific knowledge and, considering the regional differences in relation to the development of oral diseases, we recommend that proposals for standardizing surveys be checked periodically. Other important issues may have not been detected in this analysis, urging a thorough discussion within the dentistry community as a whole.
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Epidemiological surveys are important for obtaining information on the prevalence and etiology of mouth diseases, since the data collected permit health actions to be planned, performed, and assessed. Methodological uniformity is necessary, however, to maintain reproductibility, validity, and reliability, and to allow national and international comparisons. The initiative of the World Health Organization (WHO) as an advisor in ongoing surveys has been extremely useful, stimulating standardization in all countries. In 1991, a Portuguese version of the 1987 third edition of Oral Health Surveys - basic methods, an instruction manual for performing epidemiological surveys, was published and became a reference for many parts of Brazil and the World. The present analysis found conflicting points in relation to the sample size, calibration of the examiners, and criteria for evaluating oral health and treatment needs. In conclusion, due to the dynamic characteristics of scientific knowledge and, considering the regional differences in relation to the development of oral diseases, we recommend that proposals for standardizing surveys be checked periodically. Other important issues may have not been detected in this analysis, urging a thorough discussion within the dentistry community as a whole.
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Background and Objectives: A woman's lifetime risk of major depression is almost twice as high as that of a man. Major depression is associated with a high risk of recurrence, but the question of a differential risk of recurrence between genders is unclear. Based on a systematic review of the literature, this paper attempts to answer the following question: "Following a major depressive episode, do women and men have the same risk of recurrence?". Methods: We prospectively collected all studies from the period 2005-2014 where the variable gender was considered a potential predictor of recurrence. The database has also been expanded with articles cited in the bibliography of the prospectively collected articles and with a PubMed Database search covering the period January 2005-August 2014. Results: Of the prospective studies (n = 98), most found no influence of gender on recurrence risk, but a minority, mostly large sample studies, found that female gender is a statistically significant risk factor for recurrence. Results suggest a probable female-to-male relative risk of recurrence between 1.0 and 1.2. Given the heterogeneity of the studies (length of follow-up, populations, nature of the studies, choice of dependant variables, statistical methods, and available data) no meta-analyses were performed. There are many interfering variables (age of onset, subchronic evolution, treatments, etc.) that can influence the results of prospective studies. Conclusions: Women probably have a slightly higher risk of recurrence after a major depressive episode than men. This increased risk is much smaller than women's much higher lifetime risk of depression.
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For environmental quality assessment, INAA has been applied for determining chemical elements in small (200 mg) and large (200 g) samples of leaves from 200 trees. By applying the Ingamells` constant, the expected percent standard deviation was estimated in 0.9-2.2% for 200 mg samples. Otherwise, for composite samples (200 g), expected standard deviation varied from 0.5 to 10% in spite of analytical uncertainties ranging from 2 to 30%. Results thereby suggested the expression of the degree of representativeness as a source of uncertainty, contributing for increasing of the reliability of environmental studies mainly in the case of composite samples.