978 resultados para high-speed measurement of polarized state


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Purpose: Assessing health-related quality of life (HRQoL) via Computerized Adaptive Tests (CAT) provides greater measurement precision coupled with a lower test burden compared to conventional tests. Currently, there are no European pediatric HRQoL CATs available. This manuscript aims at describing the development of a HRQoL CAT for children and adolescents: the Kids-CAT, which was developed based on the established KIDSCREEN-27 HRQoL domain structure. Methods: The Kids-CAT was developed combining classical test theory and item response theory methods and using large archival data of European KIDSCREEN norm studies (n = 10,577–19,580). Methods were applied in line with the US PROMIS project. Item bank development included the investigation of unidimensionality, local independence, exploration of Differential Item Functioning (DIF), evaluation of Item Response Curves (IRCs), estimation and norming of item parameters as well as first CAT simulations. Results: The Kids-CAT was successfully built covering five item banks (with 26–46 items each) to measure physical well-being, psychological well-being, parent relations, social support and peers, and school well-being. The Kids-CAT item banks proved excellent psychometric properties: high content validity, unidimensionality, local independence, low DIF, and model conform IRCs. In CAT simulations, seven items were needed to achieve a measurement precision between.8 and.9 (reliability). It has a child-friendly design, is easy accessible online and gives immediate feedback reports of scores. Conclusions: The Kids-CAT has the potential to advance pediatric HRQoL measurement by making it less burdensome and enhancing the patient–doctor communication.

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Abstract
Purpose
Assessing health-related quality of life (HRQoL) via Computerized Adaptive Tests (CAT) provides greater measurement precision coupled with a lower test burden compared to conventional tests. Currently, there are no European pediatric HRQoL CATs available. This manuscript aims at describing the development of a HRQoL CAT for children and adolescents: the Kids-CAT, which was developed based on the established KIDSCREEN-27 HRQoL domain structure.
Methods
The Kids-CAT was developed combining classical test theory and item response theory methods and using large archival data of European KIDSCREEN norm studies (n=10,577–19,580). Methods were applied in line with the US PROMIS project. Item bank development included the investigation of unidimensionality, local independence, exploration of Differential Item Functioning (DIF), evaluation of Item Response Curves (IRCs), estimation and norming of item parameters as well as first CAT simulations.
Results
The Kids-CAT was successfully built covering five item banks (with 26–46 items each) to measure physical well-being, psychological well-being, parent relations, social support and peers, and school well-being. The Kids-CAT item banks proved excellent psychometric properties: high content validity, unidimensionality, local independence, low DIF, and model conform IRCs. In CAT simulations, seven items were needed to achieve a measurement precision between .8 and .9 (reliability). It has a child-friendly design, is easy accessible online and gives immediate feedback reports of scores.
Conclusions
The Kids-CAT has the potential to advance pediatric HRQoL measurement by making it less burdensome and enhancing the patient–doctor communication.

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INTRODUCTION: Patient participation in healthcare is recognised internationally as essential for consumer-centric, high-quality healthcare delivery. Its measurement as part of continuous quality improvement requires development of agreed standards and measurable indicators. AIM: This systematic review sought to identify strategies to measure patient participation in healthcare and to report their reliability and validity. In the context of this review, patient participation was constructed as shared decision-making, acknowledging the patient as having critical knowledge regarding their own health and care needs and promoting self-care/autonomy. METHODS: Following a comprehensive search, studies reporting reliability or validity of an instrument used in a healthcare setting to measure patient participation, published in English between January 2004 and March 2014 were eligible for inclusion. RESULTS: From an initial search, which identified 1582 studies, 156 studies were retrieved and screened against inclusion criteria. Thirty-three studies reporting 24 patient participation measurement tools met inclusion criteria, and were critically appraised. The majority of studies were descriptive psychometric studies using prospective, cross-sectional designs. Almost all the tools completed by patients, family caregivers, observers or more than one stakeholder focused on aspects of patient-professional communication. Few tools designed for completion by patients or family caregivers provided valid and reliable measures of patient participation. There was low correlation between many of the tools and other measures of patient satisfaction. CONCLUSION: Few reliable and valid tools for measurement of patient participation in healthcare have been recently developed. Of those reported in this review, the dyadic Observing Patient Involvement in Decision Making (dyadic-OPTION) tool presents the most promise for measuring core components of patient participation. There remains a need for further study into valid, reliable and feasible strategies for measuring patient participation as part of continuous quality improvement.

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The authors investigated whether male violent juvenile offenders demonstrate any differences in local functional connectivity indicative of delayed maturation of the brain that may serve as a biomarker of violence. Twenty-nine violent juvenile offenders and 28 age-matched controls were recruited. Regional homogeneity (ReHo) method was used to analyze resting-state magnetic resonance images. Violent offenders showed significantly lower ReHo values in the right caudate, right medial prefrontal cortex, and left precuneus, and higher values in the right supramarginal gyrus than the controls. These regions had both high sensitivity and specificity in distinguishing between the two groups suggesting that dysfunction in these regions can be used to correctly classify those individuals who are violent. Dysfunction in the right medial prefrontal-caudate circuit may, therefore, represent an important biomarker of violence juvenile males.

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Although great attention has been paid to wearable electronic devices in recent years, flexible lightweight batteries or supercapacitors with high performance are still not readily available due to the limitations of the flexible electrode inventory. In this work, highly flexible, bendable and conductive rGO-PEDOT/PSS films were prepared using a simple bar-coating method. The assembled device using rGO-PEDOT/PSS electrode could be bent and rolled up without any decrease in electrochemical performance. A relatively high areal capacitance of 448 mF cm(-2) was achieved at a scan rate of 10 mV s(-1) using the composite electrode with a high mass loading (8.49 mg cm(-2)), indicating the potential to be used in practical applications. To demonstrate this applicability, a roll-up supercapacitor device was constructed, which illustrated the operation of a green LED light for 20 seconds when fully charged.

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The increase in the importance of intangibles in business competitiveness has made investment selection more challenging to investors that, under high information asymmetry, tend to charge higher premiums to provide capital or simply deny it. Private Equity and Venture Capital (PE/VC) organizations developed contemporarily with the increase in the relevance of intangible assets in the economy. They form a specialized breed of financial intermediaries that are better prepared to deal with information asymmetry. This paper is the result of ten interviews with PE/VC organizations in Brazil. Its objective is to describe the selection process, criteria and indicators used by these organizations to identify and measure intangible assets, as well as the methods used to valuate prospective investments. Results show that PE/VC organizations rely on sophisticated methods to assess investment proposals, with specific criteria and indicators to assess the main classes of intangible assets. However, no value is given to these assets individually. The information gathered is used to understand the sources of cash flows and risks, which are then combined by discounted cash flow methods to estimate firm's value. Due to PE/VC organizations extensive experience with innovative Small and Medium-sized Enterprises (SMEs), we believe that shedding light on how PE/VC organizations deal with intangible assets brings important insights to the intangible assets debate.

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A quantificação da evaporação do solo é requerida em estudos de balanço hídrico de culturas e em aplicações que visam a aumentar a eficiência do uso da água pelos cultivos. O objetivo deste trabalho foi testar um modelo de microlisímetro (ML) para medir a evaporação do solo em condições irrigada e não irrigada. Os MLs foram construídos utilizando tubos de PVC rígido, medindo 100 mm de diâmetro interno, 150 mm de profundidade e 2,5 mm de espessura da parede. Quatro MLs foram assentados sobre a superfície de dois lisímetros de pesagem de alta precisão conduzidos com solo nu, previamente instalados no Iapar, em Londrina-PR. Os lisímetros tinham dimensões de 1,4 m de largura, 1,9 m de comprimento e 1,3 m de profundidade, e estavam sendo conduzidos com e sem irrigação. A evaporação medida nos MLs (E ML) foi comparada com a medida nos lisímetros (E L), durante quatro períodos do ano. As diferenças entre E ML e E L foram mínimas para condições de baixa e elevada demanda atmosférica, e também para condições de solo irrigado ou não irrigado, indicado que o modelo de ML testado neste trabalho é adequado para medir a evaporação do solo.

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The high-energy states of a shallow donor in a GaAs/Ga0.7Al0.3As multiple-quantum-well structure subjected to a magnetic field in the growth direction are studied both theoretically and experimentally. Effects due to higher confinement subbands as well as due to the electron-phonon interaction are investigated. We show that most of the peaks in the infrared photoconductivity spectrum are due to direct transitions from the ground state to the m = +/-1 magnetodonor states associated with the first subband, but transitions to the m = +/-1 states of the third subband are also apparent. The remaining photoconductivity peaks are explained by phonon-assisted impurity transitions.

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Based on analyses of high-speed video recordings of cloud-to-ground lightning in Brazil and the USA, the characteristics of positive cloud-to-ground (+CG) leaders are presented. The high frame rates permitted the average, 2-dimensional speeds of development along the paths of the channels to be resolved with good accuracy. The values range from 0.3 to 6.0 x 10(5) ms(-1) with a mean of 2.7 x 10(5) ms(-1). Contrary to what is usually assumed, downward +CG leader speeds are similar to downward -CG leader speeds. Our observations also show that the speeds tend to increase by a factor of 1.1 to 6.5 as they approach the ground. The presence of short duration, recoil leaders (RLs) during the development of positive leaders reveal a highly branched structure that is not usually recorded when using conventional photographic and video cameras. The existence of the RLs may help to explain observations of UHF-VHF radiation during the development of +CG flashes.

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The aim of this study was to compare intrapulpal temperature increase produced by high-speed handpiece, Er:YAG laser and CVDentus ultrasound tips during cavity preparation. Thirty bovine mandibular incisors with an enamel/dentin thickness of 4 mm at buccal surface had their roots amputated and were allocated to the following groups (n=10): Group I- high-speed handpiece; Group II- noncontact Er:YAG laser (250 mJ/4Hz); and Group III- CVDentus ultrasouns tips. All devices were used with water cooling. Class V cavities were prepared to a depth of 3.5 mm, measured with a periodontal probe. A type T thermocouple was placed inside the pulp chamber to determine the temperature increase (degrees C), which was recorded by a data acquisition system ADS 2000 IP (Lynx Technology) linked to a notebook computer. Data were analyzed statistically by oneway ANOVA and Tukey's test (p=0.05). The mean temperature rises were: 1.10 degrees C ( 0.56) for Group 1, 0.84 degrees C (0.55) for Group II, and 3.00 degrees C (1.34) for Group III. There were no statistically significant differences (p > 0.05) between Groups I and II, but both of them differed significantly from Group III (p < 0.05). In conclusion, the use of Er:YAG laser and high-speed handpiece for cavity preparation resulted in similar temperature increase. Although ultrasound tips generated significantly higher intrapulpal temperature increase, it remained below the critical value of 5.5 degrees C and may be considered safe for use.

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We present measurements of the inclusive production cross sections of the Upsilon(1S) bottomonium state in p (p) over bar collisions at root s=1.96 TeV. Using the Upsilon(1S)->mu(+)mu(-) decay mode for a data sample of 159 +/- 10 pb(-1) collected by the D0 detector at the Fermilab Tevatron collider, we determine the differential cross sections as a function of the Upsilon(1S) transverse momentum for three ranges of the Upsilon(1S) rapidity: 0 <\y(Upsilon)\<= 0.6, 0.6 <\y(Upsilon)\<= 1.2, and 1.2 <\y(Upsilon)\<= 1.8.

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We present a measurement of the top quark pair (t (t) over bar) production cross section (sigma(t (t) over bar)) in pp collisions at root s = 1.96 TeV using 230 pb(-1) of data collected by the DO experiment at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), missing transverse energy, and jets in the final state. We employ lifetime-based b-jet identification techniques to further enhance the t F purity of the selected sample. For a top quark mass of 175 GeV, we measure sigma(t (t) over bar) 8.6(-1.5)(+1.6) (stat. + syst.) +/- 0.6(lumi.) pb, in agreement with the standard model expectation. (c) 2005 Published by Elsevier B.V.

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We present a measurement of the W boson pair-production cross section in p(p) over bar collisions at a center-of-mass energy of root s=1.96 TeV. The data, collected with the Run II D0 detector at Fermilab, correspond to an integrated luminosity of 224-252 pb(-1) depending on the final state (ee, e mu, or mu mu). We observe 25 candidates with a background expectation of 8.1 +/- 0.6(stat)+/- 0.6(syst)+/- 0.5(lum) events. The probability for an upward fluctuation of the background to produce the observed signal is 2.3x10(-7), equivalent to 5.2 standard deviations. The measurement yields a cross section of 13.8(-3.8)(+4.3)(stat)(-0.9)(+1.2)(syst)+/- 0.9(lum) pb, in agreement with predictions from the standard model.

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We present a measurement of the fraction f(+) of right-handed W bosons produced in top quark decays, based on a candidate sample of tt events in the l + jets and dilepton decay channels corresponding to an integrated luminosity of 370 pb(-1) collected by the D0 detector at the Fermilab Tevatron pp Collider at root s = 1.96 TeV. We reconstruct the decay angle theta* for each lepton. By comparing the cos theta* distribution from the data with that for the expected background and signal for various values of f(+) (where we assume that the fraction of longitudinally-polarized W bosons has the standard model value of 0.70), we find f(+) = 0.056 +/- 0.080 (stat) +/- 0.057 (syst) (f(+) < 0.23 at 95% C. L.), consistent with the standard model prediction of f(+) = 3.6 X 10(-4).

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A measurement of the top quark mass using events with one charged lepton, missing transverse energy, and jets in the final state, collected by the D0 detector from p (p) over bar collisions at root s=1.96 TeV at the Fermilab Tevatron collider, is presented. A constrained fit is used to fully reconstruct the kinematics of the events. For every event a top quark mass likelihood is calculated taking into account all possible jet assignments and the probability that an event is signal or background. Lifetime-based identification of b jets is employed to enhance the separation between t (t) over bar signal and background from other physics processes and to improve the assignment of the observed jets to the quarks in the t (1) over bar hypothesis. We extract a multiplicative jet energy scale (JES) factor in situ, greatly reducing the systematic effect related to the jet energy measurement. In a data sample with an integrated luminosity of 425 pb(-1), we observe 230 candidate events, with an estimated background of 123 events, and measure m(t)=173.7 +/- 4.4(stat+JES)(-2.0)(+2.1)(syst) GeV. This result represents the first application of the ideogram technique to the measurement of the top quark mass in lepton+jets events.