989 resultados para sample correlation


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Regression equations predicting dissectable muscle weight in rabbits from external measurements were presented. Bone weight and weight of muscle groups were also carcass predicted. Predictive capacity of external measurements, retail cuts and muscle groups on total muscle, percent muscle, total bone and muscle to bone ratio were studied separately. Measurements on dissected retail cuts should be included in ordcr to obtain good equations for prediction of percent muscle in the carcass. Equations for predicting the muscle to bone ratio using external mcasurcments and data from the dissection of one hind leg were suggested. The equations had generally high coefficients of determination. The coefficient of determination for prediction of dissectable muscle was 0.91, and for percent muscle in the carcass 0.79.

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OBJECTIVE: To evaluate the variability of bond strength test results of adhesive systems (AS) and to correlate the results with clinical parameters of clinical studies investigating cervical restorations. MATERIALS AND METHODS: Regarding the clinical studies, the internal database which had previously been used for a meta-analysis on cervical restorations was updated with clinical studies published between 2008 and 2012 by searching the PubMed and SCOPUS databases. PubMed and the International Association for Dental Research abstracts online were searched for laboratory studies on microtensile, macrotensile and macroshear bond strength tests. The inclusion criteria were (1) dentin, (2) testing of at least four adhesive systems, (3) same diameter of composite and (4) 24h of water storage prior to testing. The clinical outcome variables were retention loss, marginal discoloration, detectable margins, and a clinical index comprising the three parameters by weighing them. Linear mixed models which included a random study effect were calculated for both, the laboratory and the clinical studies. The variability was assessed by calculating a ratio of variances, dividing the variance among the estimated bonding effects obtained in the linear mixed models by the sum of all variance components estimated in these models. RESULTS: Thirty-two laboratory studies fulfilled the inclusion criteria comprising 183 experiments. Of those, 86 used the microtensile test evaluating 22 adhesive systems (AS). Twenty-seven used the macrotensile test with 17 AS, and 70 used the macroshear test with 24 AS. For 28 AS the results from clinical studies were available. Microtensile and macrotensile (Spearman rho=0.66, p=0.007) were moderately correlated and also microtensile and macroshear (Spearman rho=0.51, p=0.03) but not macroshear and macrotensile (Spearman rho=0.34, p=0.22). The effect of the adhesive system was significant for microtensile and macroshear (p<0.001) but not for macrotensile. The effect of the adhesive system could explain 36% of the variability of the microtensile test, 27% of the macrotensile and 33% of the macroshear test. For the clinical trials, about 49% of the variability of retained restorations could be explained by the adhesive system. With respect to the correlation between bond strength tests and clinical parameters, only a moderate correlation between micro- and macrotensile test results and marginal discoloration was demonstrated. However, no correlation between these tests and a retention loss or marginal integrity was shown. The correlation improved when more studies were included compared to assessing only one study. SIGNIFICANCE: The high variability of bond strength test results highlights the need to establish individual acceptance levels for a given test institute. The weak correlation of bond-strength test results with clinical parameters leads to the conclusion that one should not rely solely on bond strength tests to predict the clinical performance of an adhesive system but one should conduct other laboratory tests like tests on the marginal adaptation of fillings in extracted teeth and the retention loss of restorations in non-retentive cavities after artificial aging.

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AIM: Longitudinal studies that have examined cognitive performance in children with intellectual disability more than twice over the course of their development are scarce. We assessed population and individual stability of cognitive performance in a clinical sample of children with borderline to mild non-syndromic intellectual disability. METHOD: Thirty-six children (28 males, eight females; age range 3-19y) with borderline to mild intellectual disability (Full-scale IQ [FSIQ] 50-85) of unknown origin were examined in a retrospective clinical case series using linear mixed models including at least three assessments with standardized intelligence tests. RESULTS: Average cognitive performance remained remarkably stable over time (high population stability, drop of only 0.38 IQ points per year, standard error=0.39, p=0.325) whereas individual stability was at best moderate (intraclass correlation of 0.58), indicating that about 60% of the residual variation in FSIQ scores can be attributed to between-child variability. Neither sex nor socio-economic status had a statistically significant impact on FSIQ. INTERPRETATION: Although intellectual disability during childhood is a relatively stable phenomenon, individual stability of IQ is only moderate, likely to be caused by test-to-test reliability (e.g. level of child's cooperation, motivation, and attention). Therefore, clinical decisions and predictions should not rely on single IQ assessments, but should also consider adaptive functioning and previous developmental history.

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We performed a number of tests with the aim to develop an effective extraction method for the analysis of carotenoid content in maize seed. Mixtures of methanol–ethyl acetate (6:4, v/v) and methanol–tetrahydrofuran (1:1, v/v) were the most effective solvent systems for carotenoid extraction from maize endosperm under the conditions assayed. In addition, we also addressed sample preparation prior to the analysis of carotenoids by liquid chromatography (LC). The LC response of extracted carotenoids and standards in several solvents was evaluated and results were related to the degree of solubility of these pigments. Three key factors were found to be important when selecting a suitable injection solvent: compatibility between the mobile phase and injection solvent, carotenoid polarity and content in the matrix.

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El propósito de este trabajo es presentar la construcción y aplicación del Questionari de Desarrollo Emocional para Adultos (QDE-A). Se trata de la versión catalana del Cuestionario de Desarrollo Emocional para Adultos (CDE-A). Los instrumentos disponibles para la medición de la competencia emocional son escasos y todos ellos sujetos a criticas centradas fundamentalmente en la falta de un marco teórico claro y de fundamentos empíricos firmes (Pérez, Petrides y Furnham, 2005). El QDE-A, se enmarca en la línea de investigación sobre educación emocional del GROP (Grupo de Investigación en Orientación Psicopedagógica). Se trata de un cuestionario de autoinforme basado en el marco teórico de la educación emocional desarrollado por el GROP (Bisquerra, 2000 y 2007) según el cual la competencia emocional se compone de cinco dimensiones: conciencia emocional, regulación emocional, autonomía emocional, competencias sociales y competencias para la vida y el bienestar. El QDE-A ofrece una puntuación global y otra para cada una de estas dimensiones. En este artículo se expone el proceso de elaboración para llegar a la versión definitiva que en su forma extensa consiste en una escala que dispone de 48 ítems. Los datos se basan en una muestra de 1537 adultos. La fiabilidad medida por el alfa de Cronbach es de 0,92, para la escala completa y superior a 0.70 para cada una de las dimensiones. La correlación entre cada una de las dimensiones y la puntuación total es significativa en todos los casos con un nivel de p<0.01. El QDE-A responde a la necesidad de disponer de un instrumento riguroso, adaptado a la población catalana, que permite evaluar el nivel de competencia emocional en adultos y fundamentar las intervenciones en educación emocional.

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OBJECTIVES: The goal of this study was to assess the clinical usefulness of the emotional symptoms (Emo) and externalizing problems (Ext) scales compared with the Total score on the Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA). METHODS: The HoNOSCA was rated at admission and discharge for 260 adolescent inpatients. The primary outcomes assessed were (a) the sensitivity of the 3 HoNOSCA scores to clinical improvement; and (b) the between diagnoses discriminative value of these scores. RESULTS: Analyses of variances [2 (time: admission vs. discharge) ×5 (diagnostic groups)] revealed a main effect of time for the 3 scores, a main effect of the diagnostic group for the Total and Ext scores, and an interaction effect between time and diagnosis for the Emo score. A moderate correlation was observed between the change in Ext and Emo scores between admission and discharge. DISCUSSION: These 2 new scales of the HoNOSCA demonstrated good clinical utility and the ability to assess different aspects of clinical improvements. A significant discriminative value of both scores was observed. SIGNIFICANT OUTCOMES: The clinical utility of the 2 new scales on the HoNOSCA was established. These 2 new scales provided a sensitive measure of clinical outcome for assessing improvement between admission and discharge on a psychiatric inpatient unit for adolescents, regardless of diagnostic group, and captured additional information about clinical improvements. Adolescents with psychosis and conduct disorders presented with higher externalizing symptoms than those with other disorders, as rated on the HoNOSCA, at admission and discharge. The Emo score differentiated between clinical improvement in patients with psychosis versus eating disorders. LIMITATIONS: The sample in this study represented a homogeneous population of adolescent inpatients, so that further research is needed before these findings can be generalized to outpatients. In addition, the small number of patients in some diagnostic groups did not allow for their inclusion in some of the statistical analyses.

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Objectives To develop and validate a Spanish version of the Athens Insomnia Scale (AIS). Methods The AIS is designed to assess sleep difficulty and comprises eight items: the first five refer to the sleep disturbance and the last three to the daytime consequences. Either the full eight-item scale (AIS-8) or the brief form (AIS-5) can be administered. The adaptation used a backtranslation design. The validation process was based on a sample of 323 participants (undergraduates, community sample and psychiatric outpatients), which completed the AIS and other questionnaires: anxiety (BAI), depression (BDI) and psychological well-being (GHQ-12) scales. Results The internal consistency coefficients for both versions were above 0.80. The study of dimensionality revealed a single factor with high loadings and a percentage of explained variance above 50% in both versions. Test-retest reliability was above 0.70 (AIS-5) and over 0.80 (AIS-8) at a one-month interval. The correlation between the AIS and the previously mentioned scales was for both the AIS-5 and the AIS-8 above 0.40 and 0.50, respectively.

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The goal of the present study is to examine cross-sectional information on the growth of the humerus based on the analysis of four measurements, namely, diaphyseal length, transversal diameter of the proximal (metaphyseal) end of the shaft, epicondylar breadth and vertical diameter of the head. This analysis was performed in 181 individuals (90 ♂ and 91 ♀) ranging from birth to 25 years of age and belonging to three documented Western European skeletal collections (Coimbra, Lisbon and St. Bride). After testing the homogeneity of the sample, the existence of sexual differences (Student"s t- and Mann-Whitney U-test) and the growth of the variables (polynomial regression) were evaluated. The results showed the presence of sexual differences in epicondylar breadth above 20 years of age and vertical diameter of the head from 15 years of age, thus indicating that these two variables may be of use in determining sex from that age onward. The growth pattern of the variables showed a continuous increase and followed first- and second-degree polynomials. However, growth of the transversal diameter of the proximal end of the shaft followed a fourth-degree polynomial. Strong correlation coefficients were identified between humeral size and age for each of the four metric variables. These results indicate that any of the humeral measurements studied herein is likely to serve as a useful means of estimating sub-adult age in forensic samples.

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Työn tavoitteena oli kehittää Metsä Tissue Oyj:n Mäntän tehtaille uusi testimenetelmä leivinpaperin rasvanläpäisyn mittaamiseen. Uudella testimenetelmällä korvataan kaksi nykyisistä testimenetelmistä, jotka ovat aikaa vieviä ja epäluotettavia. Uudelta menetelmältä vaaditaan lyhyttä kestoa, hyvää toistettavuutta ja luotettavuutta sekä korreloivuutta nykyisiin testimenetelmiin. Nykyisissä testeissä leivinpaperilla paistetaan sikaa ja kanaa uunissa, jonka jälkeen tarkastetaan leivinpaperin läpäisseen rasvan määrää leivinpaperin alla olleen lautasen puhtauden perusteella. Sikatesti on huomattavasti kriittisempi kuin kanatesti, joten tässä työssä keskitytään sikatestin korvaamiseen uudella testimenetelmällä. Työn kirjallisuusosassa perehdyttiin rasvatiiviisiin papereihin, niiden valmistukseen ja ominaisuuksiin. Lähinnä keskityttiin tiivispaperin valmistukseen ja sen silikonointiin. Lisäksi esitettiin rasvanläpäisyn mekanismeja ja niihin vaikuttavia tekijöitä sekä rasvanläpäisyn mittaamiseen kehitettyjä menetelmiä. Kokeellisen osan alussa tehtiin esikokeita olemassa olevilla testeillä, kuten Helga- ja Tappi-rasvatiiveystestillä, DIN 53116 standardin mukaisella menetelmällä sekä DPM menetelmällä. Esikokeiden tarkoituksena oli selvittää missä määrin sikatesti korreloi muiden testimenetelmien kanssa. Näistä menetelmistä ei löydetty korrelaatiota sikatestiin, joten kehitettiin aivan uusi testimenetelmä. Kokeellisessa osassa tutkittiin sikatestissä leivinpaperin pidättämiä ja läpäisemiä aineita. Testeissä huomattiin, että leivinpaperin läpäisseet aineet olivat pääosin vesiliukoisia proteiineja. Leivinpaperin pidättämässä aineessa oli vettä, vesiliukoista proteiineja ja rasvaa, siasta riippuen hyvinkin erilaisissa suhteissa. Täten todettiin sikatestin huono toistettavuus ja luotettavuus. Uudessa testimenetelmässä leivinpaperia ja sen päällä olevaa koeainetta puristetaan määrätyllä paineella määrätyssä lämpötilassa, jonka jälkeen leivinpaperin läpäissyt rasva havainnoidaan leivinpaperin alla olevasta indikaattoripaperista. Lopuksi lasketaan tietynkokoisten läpimenotahrojen lukumäärän perusteella näytteelle rasvan läpäisyindeksi. Uusi menetelmä korreloi sekä sika- että kanatestin kanssa.

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Purpose: Wolfram syndrome is a degenerative, recessive rare disease with an onset in childhood. It is caused by mutations in WFS1 or CISD2 genes. More than 200 different variations in WFS1 have been described in patients with Wolfram syndrome, which complicates the establishment of clear genotype-phenotype correlation. The purpose of this study was to elucidate the role of WFS1 mutations and update the natural history of the disease. Methods: This study analyzed clinical and genetic data of 412 patients with Wolfram syndrome published in the last 15 years. Results: (i) 15% of published patients do not fulfill the current ­inclusion criterion; (ii) genotypic prevalence differences may exist among countries; (iii) diabetes mellitus and optic atrophy might not be the first two clinical features in some patients; (iv) mutations are nonuniformly distributed in WFS1; (v) age at onset of diabetes mellitus, hearing defects, and diabetes insipidus may depend on the patient"s genotypic class; and (vi) disease progression rate might depend on genotypic class. Conclusion: New genotype-phenotype correlations were established, disease progression rate for the general population and for the genotypic classes has been calculated, and new diagnostic criteria have been proposed. The conclusions raised could be important for patient management and counseling as well as for the development of treatments for Wolfram syndrome.

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Water soluble perchlorinated trityl (PTM) radicals were found to be effective 95 GHz DNP (dynamic nuclear polarization) polarizers in ex situ (dissolution) 13C DNP (Gabellieri et al., Angew Chem., Int. Ed. 2010, 49, 3360). The degree of the nuclear polarization obtained was reported to be dependent on the position of the chlorine substituents on the trityl skeleton. In addition, on the basis of the DNP frequency sweeps it was suggested that the 13C NMR signal enhancement is mediated by the Cl nuclei. To understand the DNP mechanism of the PTM radicals we have explored the 95 GHz EPR characteristics of these radicals that are relevant to their performance as DNP polarizers. The EPR spectra of the radicals revealed axially symmetric g-tensors. A comparison of the spectra with the 13C DNP frequency sweeps showed that although the solid effect mechanism is operational the DNP frequency sweeps reveal some extra width suggesting that contributions from EPR forbidden transitions involving 35,37Cl nuclear flips are likely. This was substantiated experimentally by ELDOR (electron-electron double resonance) detected NMR measurements, which map the EPR forbidden transitions, and ELDOR experiments that follow the depolarization of the electron spin upon irradiation of the forbidden EPR transitions. DFT (density functional theory) calculations helped to assign the observed transitions and provided the relevant spin Hamiltonian parameters. These results show that the 35,37Cl hyperfine and nuclear quadrupolar interactions cause a considerable nuclear state mixing at 95 GHz thus facilitating the polarization of the Cl nuclei upon microwave irradiation. Overlap of Cl nuclear frequencies and the 13C Larmor frequency further facilitates the polarization of the 13C nuclei by spin diffusion. Calculation of the 13C DNP frequency sweep based on the Cl nuclear polarization showed that it does lead to an increase in the width of the spectra, improving the agreement with the experimental sweeps, thus supporting the existence of a new heteronuclear assisted DNP mechanism.

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We present an analysis of factors influencing carrier transport and electroluminescence (EL) at 1.5 µm from erbium-doped silicon-rich silica (SiOx) layers. The effects of both the active layer thickness and the Si excess content on the electrical excitation of erbium are studied. We demonstrate that when the thickness is decreased from a few hundred to tens of nanometers the conductivity is greatly enhanced. Carrier transport is well described in all cases by a Poole-Frenkel mechanism, while the thickness-dependent current density suggests an evolution of both density and distribution of trapping states induced by Si nanoinclusions. We ascribe this observation to stress-induced effects prevailing in thin films, which inhibit the agglomeration of Si atoms, resulting in a high density of sub-nm Si inclusions that induce traps much shallower than those generated by Si nanoclusters (Si-ncs) formed in thicker films. There is no direct correlation between high conductivity and optimized EL intensity at 1.5 µm. Our results suggest that the main excitation mechanism governing the EL signal is impact excitation, which gradually becomes more efficient as film thickness increases, thanks to the increased segregation of Si-ncs, which in turn allows more efficient injection of hot electrons into the oxide matrix. Optimization of the EL signal is thus found to be a compromise between conductivity and both number and degree of segregation of Si-ncs, all of which are governed by a combination of excess Si content and sample thickness. This material study has strong implications for many electrically driven devices using Si-ncs or Si-excess mediated EL.