1,720,973 research outputs found
Paraffine negli alimenti e loro livelli di stoccaggio nei tessuti animali.
No full textContenuti di paraffine in mangimi e loro stoccaggio in galline ovaiole, tacchini, conigli e trote
Ulteriori dati sulla presenza di n-paraffine in comuni mangimi del commercio
No full textSono state eseguite indagini sui livelli di paraffine in mangimi impiegati in zootecnia. Il mangime secco per piccoli di trota contengono sino a 41 ppm di n-paraffine
Ricerca della eventuale attività mutagena di additivi correntemente utilizzati in Italia
No full textValidación del instrumento Montreal cognitive assessment, versión en español (MoCA-S) en adultos mayores de Santiago de Chile
Full text linkTesis para optar al grado de Magíster en Ciencias Médicas y Biológicas, Mención Neurociencias.Introducción: Actualmente Chile presenta un envejecimiento poblacional acelerado. Es
necesario contar con baterías neurocognitivas para el tamizaje de demencia y estados
predemenciales como el Deterioro Cognitivo Leve (DCL) del Adulto Mayor (AM). Estas
herramientas clínicas deben presentar adecuada validez local, fácil aplicabilidad, corta duración y
bajo costo, con énfasis en atención primaria. Nuestra hipótesis es que los puntajes de corte serán
inferiores a los reportados en países desarrollados.
Objetivo: Determinar la equivalencia del Montreal Cognitive Assessment Test, versión en
Español (MoCA-S) y la clasificación a partir del Diagnóstico Clínico de Demencia (CDR) al
discriminar entre sujetos AM con DCL amnésico y no amnésico, Demencia o cognitivamente
normales en Santiago de Chile.
Diseño: Estudio de validación para prueba diagnóstica. Transversal, descriptivo y correlacional.
Variables cuantitativas continuas y discretas. Muestra por conveniencia, muestreo no
probabilístico.
Sujetos: 205 AM voluntarios hombres y mujeres (78 y 127); 133 Controles (CDR 0) y 3 grupos
de 24 DCL amnésico (CDR 0,5), DCL no amnésico (CDR 0,5) y Demencia (CDR 1 y 2),
respectivamente. Desde centros clínicos y comunitarios.
Materiales y Método: Se contó con la aprobación de los comités de ética del Hospital Clínico y la
Facultad de Medicina de la Universidad de Chile. Los AM en compañía de un informante válido
fueron diagnosticados por 2 Neurólogas con los criterios del DSMIV y NINCDS-ADRDA, que
estratificaron el diagnóstico en base al CDR. Luego fueron tamizados con MoCA-S y MMSE, de
forma ciega. La brecha de tiempo entre las evaluaciones no fue superior a 3 meses. Todos los
individuos estudiados firmaron consentimiento informado y cumplieron los criterios de inclusión.
Análisis de Datos: Un análisis ANOVA de un factor y post Hoc de Bonferroni comparó las
medias totales y por ítems del MoCA-S entre grupos. Se construyeron curvas ROC (Receiver
Operating Chraracteristics) entre los resultados del CDR y MoCA-S (Validez Discriminante),
calculando Sensibilidad (S), Especificidad (E), valor predictivo positivo (+VP), negativo (-VP) y
Area Bajo la Curva (ABC), entre Controles (C) v/s DCL amnésico (amn), DCL no amnésico (no
amn) y Demencia (D), respectivamente. Se determinó la influencia de la edad, la escolaridad
(ANCOVA y Correlaciones de Pearson) y género en los resultados. Se compararon los rendimientos de MoCA-S v/s MMSE como test de contraste, así como también con el CDR
mediante correlaciones de Pearson (Validez Concurrente). Finalmente, se calculó la consistencia
interna (α de Cronbach), fiabilidad inter e intraevaluador (coeficiente de Spearman), estos
últimos a partir de submuestras.
Resultados: El puntaje medio del MoCA-S fue de 24,42±3,7 para C, 22,13±5,02 para DCL no
amn, 16,83±3,9 para el DCL amn y 14,25±4,87 para D. Se observaron diferencias significativas
en edad entre C v/s DCL amn y C v/s D. En escolaridad, sólo entre el C v/s DCL Amn. Tras
controlar el efecto de estas variables (F=50,02; p<0,001), se observaron diferencias significativas
de medias entre todos los grupos a excepción los grupos C v/s DCL no amn (p=0,155). La
comparación de medias por ítem evidenció diferencias significativas entre los grupos C y DCL no
amn en los ítems: visoespacial/ejecutivo y lenguaje (p<0,001). Entre los grupos C y el DCL amn
en los dominios: visoespacial/ejecutivo, atención, lenguaje, abstracción y recuerdo diferido
(p<0,05) y entre los grupos C y D todos en todos los ítems (p<0,001) a excepción de
identificación (p=0,289). El máximo rendimiento del MoCA-S para distinguir entre C y DCL no
amn fue a los 21 puntos (ABC=0,629; S=41,67%; E=78,95%; +VP=29%; -VP=88,1%); para
distinguir C de DCL amn fue de 22 puntos (ABC=0,918; S=91,67%; E=72,93% +VP=37%; -
VP=98%) y para distinguir al grupo C de D fue de 19 puntos (ABC=0,959; S=90%; E=87,97%
+VP=52,9%; -VP=98,3%) en las Curvas ROC. La consistencia interna fue de 0,702. La fiabilidad
para el total del test Inter-evaluador (n=49) fue de 0,846 bilateral (p<0,01) e intra-evaluador
(n=37) fue 0,922 bilateral (p<0,001). La correlación edad v/s CDR fue r = 0,29 (p<0,0001) y edad
v/s MoCA-S fue r = - 0,37 (p<0,0001). La correlación escolaridad v/s CDR r = -1,37 (p= 0,049) y
escolaridad v/s MoCA-S fue significativa r = 0,423 (p<0,0001). La correlación MoCA-S v/s CDR
fue r = -0,64 (p<0,0001). No se observaron diferencias asociadas al género. La comparación de
las ABC entre MoCA-S y MMSE para la correcta clasificación de C vs DCL amn fue significativa
(p<0,0001). La correlación entre el MMSE y el MoCA-S fue r = 0,695 (p< 0,0001), se observó un
46% y 79% de D correctamente clasificados, respectivamente. Para el grupo DCL amn el MoCA S clasificó correctamente al 87,5%, mientras que el MMSE sólo 12,5%. De los sujetos C, el 100%
fue correctamente clasificado por el MMSE versus el 85% con el MoCA-S.
Conclusión: La versión en español del MoCA-S resultó eficaz y válida para la detección del DCL
amnésico y Dementes, fue menos eficaz en el tamizaje del DCL no amnésico. Su rendimiento fue
mejor que el del MMSE para el DCL. En concordancia con nuestra hipótesis, los puntajes de
corte en nuestra población de estudio fueron inferiores a las validaciones reportadas en países
desarrollados.Introduction: Aging of the population in Chile has become increasingly higher over the last
decades. Neurocognitive tests with suitable validity, easy applicability, short time and low cost,
especially for primary care is necessary for screening dementia and predemential conditions such
as Mild Cognitive Impairment (MCI) in Elderly People (EP). We hypothesize that the cut points for
screening tests in our population of study will be lower than those reported in developed countries.
Aim: To determine the equivalence of the Montreal Cognitive Assessment Test, Spanish version
(MoCA-S) with the dementia classification obtained with the Clinical Dementia Rating (CDR) on
discriminating between EP with amnesic and not amnesic MCI, Dementia, or cognitive normal in
the city of Santiago in Chile.
Design: Validation study for diagnosis test. Transversal, descriptive and correlational.
Quantitative continuous and discreet variables. Sample for convenience, non-probabilistic
sampling.
Subjects: 205 voluntary EP, men and women (78 and 127); 133 Controls (CDR 0) and 3 groups
of 24 amnesic MCI (CDR 0,5), not amnesic MCI (CDR 0,5), and Dementia (CDR 1 and 2),
respectively recruited from clinical and community centers.
Materials and Method: Approval of the ethics committees of the Hospital Clínico and the
Facultad de Medicina of the Universidad de Chile. The EP accompanied by a valid informant were
diagnosed by 2 neurologists with the DSMIV and NINCDS-ADRDA criteria, and stratified the
dementia degree based on the CDR. Then they were screened by MoCA-S and MMSE, blinded
from the neurological diagnosis. The gap of time between the evaluations was not superior to 3
months. All the individuals studied signed informed assent and fulfilled the criteria of incorporation.
Data Analysis: ANOVA analysis of one factor and Bonferroni´s post Hoc compared the averages
of the global and separate items of the MoCA-S between groups. Receiver Operating
Characteristics (ROC) curves were constructed between the results of the CDR and MoCA-S
(Criterion Validity), calculating Sensibility (S), Specificity (Sp), Positive (+VP), Negative (-VP)
predictive values and the Area Under the Curve (AUC), between Controls (C) v/s amnesic (amn)
MCI, not amnesic (not amn) MCI and Dementia (D), respectively. We examined the influence of
age, education (ANCOVA and Pearson's Correlations) and gender on the results. Performances
of MoCA-S v/s MMSE were compared as test of contrast, as well as with the CDR by Pearson's correlations (Concurrent Validity). Finally, the internal consistency (Cronbach´s Alpha), test-retest
and inter-rater reliability (Spearman's coefficient) were calculated. The latter, from subsamples.
Results: The average score of the MoCA-S was of 24,42±3,7 for C, 22,13±5,02 for not amn MCI,
16,83±3,9 for amn MCI and 14,25±4,87 for D. Differences were observed in age between C v/s
amn MCI and C v/s D, in education between the C v/s amn MCI. After controlling the effect of
these variables (F=50,02; p<0,001), significant differences of averages between all the groups
with exception of the groups C v/s not amn MCI (p=0,155) were observed. The comparison of
averages by item demonstrated significant differences between the groups C and not amn MCI in
the items: visuospatial/executive and language (p<0,001); between the groups C and the amn
MCI in the domains: visuospatial/executive, attention, language, abstraction and recollection
deferred (p<0,05); and between the groups C and D all in all the items (p <0,001) except for
identification (p=0,289).The maximum performance of the MoCA-S was 21 points to distinguish
between C and not amn MCI (AUC=0,629; S=41,67%; Sp=78,95%; +VP=29 %;-VP=88,1%), 22
points to distinguish C and amn MCI (AUC=0,918; S=91,67%; Sp=72,93% +VP=37%;-VP=98%)
and 19 points to distinguish groups C and D (AUC=0,959; S=90%; Sp=87,97% +VP=52,9%;-
VP=98,3%) in the ROC curves. The internal consistency was 0,702. The inter-rater reliability for
the total of the test (n=49) was 0,846 bilateral (p <0,01), and for the test-retest (n=37) was 0,922
bilateral (p <0,001). The correlation age v/s CDR was r = 0,29 (p <0,0001) and age v/s MoCA-S
was r = - 0,37 (p <0,0001). The correlation education v/s CDR r =-1,37 (p = 0,049) and education
v/s MoCA-S was positive and significant r = 0,423 (p <0,0001).The MoCa-S correlation v/s CDR
was r =-0,64 (p <0,0001). Gender associated differences were not observed. The comparison of
the AUC between MoCA-S and MMSE for the correct classification of C v/s amn MCI was
significant (p <0,0001). The correlation between the MMSE and the MoCA-S was r = 0,695 (p
<0,0001), with 46% and 79% of D patients correctly classified, respectively. The MoCA-S correctly
classified 87,5% of the amn MCI subjects, whereas the MMSE only 12,5 %. Of the C subjects,
100 % were correctly classified by the MMSE versus 85 % by the MoCA-S.
Conclusion: The Spanish version of the MoCA-S turned out to be effective and valid for the
detection of the amnesic MCI and Dementia persons, and was less effective in the screening of
non-amnestic MCI. Its performance was better than that of the MMSE for diagnosing MCI. In
accodance with our hypothesis, the observed cut point scores were lower than those reported for
validations in developed countries
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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