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匹配条件： “Silvia G. CRIADO” ，找到相关结果约235837条。
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Determination of Volatile Organic Compounds of Tagetes argentina Cabrera (Asteraceae) using HS-SPME analysis
Ana M. VáZQUEZ,Mario L. AIMAR,Gabriela I. DEMMEL,Silvia G. CRIADO
Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas , 2011,

Abstract: Se realizó el análisis de los componentes volátiles de T. argentina Cabrera utilizando el método de micro-extracción en fase sólida del espacio de cabeza con análisis posterior por cromatografía de gases acoplada a espectrometría de masas y por cromatografía de gases con detección por ionización de llama. Se estudio la composición de la totalidad de las partes aéreas de la planta (planta entera) como así también de las inflorescencias, hojas y tallos por separado empleando el método de HS-SPME. Como resultado, se determinaron 53 compuestos de los cuales 39 fueron identificados. Los componentes mayoritarios fueron: cis-tagetenona, trans-tagetenona, trans-tagetona and cis-tagetona. Utilizando una muy peque a cantidad de muestra, un corto periodo de tiempo y un procedimiento muy simple se lograron similares o mejores resultados a aquellos reportados mediante el análisis del aceite esencial. En conclusión, el método de HS-SPME es simple, rápido, efectivo, libre de la utilización de solventes y puede ser fácilmente implementado para el análisis de componentes volátiles provenientes de muestras de diferentes poblaciones de T. argentina.

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Phytochemistry of Tagetes minuta L. (Asteraceae) from Córdoba, Argentina: Comparative study between essential oil and HS-SPME analyses
Ana M. VáZQUEZ,Gabriela I. DEMMEL,Silvia G. CRIADO,Mario L. AIMAR
Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas , 2011,

Abstract: Se realizó el análisis de los componentes volátiles de T. minuta L. utilizando el método de micro-extracción en fase sólida del espacio de cabeza con análisis posterior por cromatografía de gases acoplada a espectrometría de masas y por cromatografía de gases con detección por ionización de llama. Se estudiaron cinco tipos de fibras comerciales que incluyeron a PA, PDMS, CAR-PDMS, PDMS-DVB y DVB-CAR-PDMS y se estableció que la fibra de DVB-CAR-PDMS es la que posee mejor comportamiento en el proceso de extracción. Se determinó el efecto del tiempo de equilibrio del espacio de cabeza, de la temperatura de extracción y del tiempo de exposición de la fibra sobre el proceso de HS-SPME. Adicionalmente, también se estudio por separado la composición de inflorescencias, hojas y tallos empleando el método de HS-SPME. Como resultado de este estudio se determinaron 68 componentes de los cuales 53 fueron identificados. Por otra parte se realizó una comparación de los resultados HS-SPME con el análisis del aceite esencial obtenido de las partes aéreas de la planta. En ambos casos, los componentes mayoritarios fueron: cis-tagetenona y trans-tagetenona. Utilizando una muy peque a cantidad de muestra, un corto periodo de tiempo y un procedimiento más simple se lograron similares resultados a los obtenidos mediante el análisis del aceite esencial. En conclusión, el método de HS-SPME desarrollado es simple, rápido, efectivo y libre de la utilización de solventes, puede ser fácilmente implementado para el análisis de componentes volátiles provenientes de muestras de diferentes poblaciones de T. minuta.

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Líneas históricas de la Novación Subjetiva por cambio de deudor con especial referencia al Derecho Castellano
Gálvez Criado,Antonio;
Revista de estudios histórico-jurídicos , 2006, DOI: 10.4067/S0716-54552006000100004

Abstract: the spanish civil code, partially following the french civil code (and the italian one of 1865, which continued the code previously mentioned), regulates the change of the debtor？s person as one of the possible applications of the novation: the subjective novation due to a change of the debtor？s person, a concept having roman origins, that, in this case, would mean the discharge of a liability with the release of the debtor and the emergence of a new liability taken over by the new debtor; one and the other casually related. article 1156 of the spanish civil code includes it as one of the possible ways of discharging liabilities, but in the more detailed regulation of articles 1203 et seq, appears rather as an assumption of modification than as a discharge of liabilities. such a regulation and the modification-discharge tension which goes along with this institute is the product of the evolution undergone by it from the adoption of the roman law on.

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Líneas históricas de la Novación Subjetiva por cambio de deudor con especial referencia al Derecho Castellano
Antonio Gálvez Criado
Revista de estudios histórico-jurídicos , 2006,

Abstract: El Código Civil espa ol, siguiendo en parte en este punto al Código civil francés (y al italiano de 1865, continuador de este último) regula el cambio de la persona del deudor como una de las posibles aplicaciones de la novación: la novación subjetiva por cambio de la persona del deudor, figura ésta de origen romano que, en este caso, significaría la extinción de una obligación con liberación de quien era su deudor y el nacimiento de otra nueva en su lugar a cargo del nuevo deudor; una y otra causalmente conectadas. El artículo 1156 del Código Civil espa ol la recoge como uno de los posibles modos de extinción de las obligaciones, pero en la regulación más detallada de los artículos 1203 ss. aparece como un supuesto más bien de modificación que de extinción de obligaciones. Tal regulación y la tensión modificación-extinción que acompa a a este instituto es fruto de la evolución sufrida por el mismo desde el Derecho romano, sobre todo durante la época Intermedia. The Spanish Civil Code, partially following the French Civil Code (and the Italian one of 1865, which continued the code previously mentioned), regulates the change of the debtor’s person as one of the possible applications of the novation: the subjective novation due to a change of the debtor’s person, a concept having Roman origins, that, in this case, would mean the discharge of a liability with the release of the debtor and the emergence of a new liability taken over by the new debtor; one and the other casually related. Article 1156 of the Spanish Civil Code includes it as one of the possible ways of discharging liabilities, but in the more detailed regulation of articles 1203 et seq, appears rather as an assumption of modification than as a discharge of liabilities. Such a regulation and the modification-discharge tension which goes along with this institute is the product of the evolution undergone by it from the adoption of the Roman law on.

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Condition metrics in the three classical spaces
Juan G. Criado del Rey
Mathematics , 2015,

Abstract: Let $(\mathcal{M},g)$ be a Riemannian manifold and $\mathcal{N}$ a $\mathcal{C}^2$ submanifold without boundary. If we multiply the metric $g$ by the inverse of the squared distance to $\mathcal{N}$, we obtain a new metric structure on $\mathcal{M}\setminus\mathcal{N}$ called the condition metric. A question about the behaviour of the geodesics in this new metric arises from the works of Shub and Beltr\'an: is it true that for every geodesic segment in the condition metric its closest point to $\mathcal{N}$ is one of its endpoints? Previous works show that the answer to this question is positive (under some smoothness hypotheses) when $\mathcal{M}$ is the Euclidean space $\mathbb{R}^n$. Here we prove that the answer is also positive for $\mathcal{M}$ being the sphere $\mathbb{S}^n$ and we give a counterexample showing that this property does not hold when $\mathcal{M}$ is the hyperbolic space $\mathbb{H}^n$.

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Common Infectious Agents and Monoclonal B-Cell Lymphocytosis: A Cross-Sectional Epidemiological Study among Healthy Adults
Delphine Casabonne, Julia Almeida, Wendy G. Nieto, Alfonso Romero, Paulino Fernández-Navarro, Arancha Rodriguez-Caballero, Santiago Mu？oz-Criado, Marcos González Díaz, Yolanda Benavente, Silvia de Sanjosé, Alberto Orfao, the Primary Health Care Group of Salamanca for the Study of MBL
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0052808

Abstract: Background Risk factors associated with monoclonal B-cell lymphocytosis (MBL), a potential precursor of chronic lymphocytic leukaemia (CLL), remain unknown. Methods Using a cross-sectional study design, we investigated demographic, medical and behavioural risk factors associated with MBL. “Low-count” MBL (cases) were defined as individuals with very low median absolute count of clonal B-cells, identified from screening of healthy individuals and the remainder classified as controls. 452 individuals completed a questionnaire with their general practitioner, both blind to the MBL status of the subject. Odds ratios (OR) and 95% confidence interval (CI) for MBL were estimated by means of unconditional logistic regression adjusted for confounding factors. Results MBL were detected in 72/452 subjects (16%). Increasing age was strongly associated with MBL (P-trend<0.001). MBL was significantly less common among individuals vaccinated against pneumococcal or influenza (OR 0.49, 95% confidence interval (CI): 0.25 to 0.95; P-value = 0.03 and OR: 0.52, 95% CI: 0.29 to 0.93, P-value = 0.03, respectively). Albeit based on small numbers, cases were more likely to report infectious diseases among their children, respiratory disease among their siblings and personal history of pneumonia and meningitis. No other distinguishing epidemiological features were identified except for family history of cancer and an inverse relationship with diabetes treatment. All associations described above were retained after restricting the analysis to CLL-like MBL. Conclusion Overall, these findings suggest that exposure to infectious agents leading to serious clinical manifestations in the patient or its surroundings may trigger immune events leading to MBL. This exploratory study provides initial insights and directions for future research related to MBL, a potential precursor of chronic lymphocytic leukaemia. Further work is warranted to confirm these findings.

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Strategic orientation, innovation and performance in new SMEs: the role of marketing
Jorge Gómez Villanueva,Joan Llonch Andreu,Josep Rialp Criado
Cuadernos de Gestión , 2010,

Abstract: Although the important role that new SME have for economic development, the relationship among three key strategic orientations as Entrepreneurial orientation (EO), Market orientation (MO) and Learning orientation (LO) with innovation and new SME′s success has not been previously analyzed. Present studies on this mater are partial because they focus in only one or two of these orientations (Li and Atuahene-Gima, 2001; Renko et al.,2009). Thus, the present research aims to fill this gap by developing a model to explain the relationship among EO, MO and LO, innovation and new SME performance and test this model within a sample of new SMEs. Empirical results from a sample of 203 new SMEs show that there is direct relationship between Market orientation (MO) and business performance, and also an indirect relationship among MO and performance through LO, EO and Innovation. However, the relationship between LO and EO with performance is only indirect, through Innovation. In summary, marketing has a critical role on the success of new SMEs.

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Acid-Base Properties of Aqueous Suspensions of Homoionic Sepiolite and Palygorskite [PDF]
Silvia G. Acebal, Leticia I. Vico
Natural Resources (NR) , 2017, DOI: 10.4236/nr.2017.86028

Abstract: Acid-base properties of Na-sepiolite and Na-palygorskite were studied by potentiometric titrations at 298 K and two ionic strength I = 0.1 and I = 0.002. Intrinsic constants of deprotonation were calculated by two different methods: a) Stumm method, by extrapolating to zero the function that relates surface charge with the logarithms of apparent acidity constants and b) with MINTEQ program by minimizing the differences between surface H+ concentration data and the values obtained from deprotonation constants proposed according to the Diffuse-Double-Layer Model (DDLM). Hydroxyl groups located at the broken edges of these fibrous clay minerals (SOH) and permanent charge sites (X^-) were considered as reactive sites. The determined values of the acid-base constants for Na-sepiolite and Na-palygorskite were intermediate between those for SiO₂ and $\"\"$ Al₂O₃, which is in agreement with minerals that contain moderately strong-acidity and weak-acidity surface groups. The SOH groups showed an initial increase (after SOH₂⁺ deprotonation), forming a plateau with a slight de-crease at high pH values (8-9) due to the formation of SO^- sites. X^- sites ad-sorbed H⁺, Na⁺ or Mg²⁺ ions.

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Sobre el concepto de aliteración
Ninfa Criado
Lexis , 2002,

Abstract:

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“The Distribution of the Lexical Component in ELT Coursebooks and its Suitability for Vocabulary Acquisition from a Cognitive Perspective. A Case Study
Raquel Criado
International Journal of English Studies (IJES) , 2009, DOI: 10.6018/ijes.1.1.99511

Abstract: The psycholinguistic and neurolinguistic perspective of language acquisition requires some essential conditions in vocabulary acquisition: a) repetitive practice, which allows for data to reach long-term memory, and thus become proceduralised and automatised; b) how relevant the lexical items are regarding the communicative needs of the learners insofar as communicative relevance is linked to frequency in general linguistic usage; c) the potential in vocabulary acquisition, which will necessarily relate to the amount of new lexical items introduced in each one of the units in textbook; d) the way words are taught, i.e. whether aimed at explicit or incidental learning. In order to analyse and evaluate these issues, we will study the lexical items presented in a specific textbook from the point of view of frequency, distribution along the manual, opportunities for rehearsal and repetition (which will depend on frequency), and the nature of the activities centred on vocabulary. The results of this case study will allow us to check whether or not they may stand a comparison against the findings of psycholinguistic and neurolinguistic research on vocabulary acquisition. Desde la perspectiva de la psicolingüística y de la neurolingüística, deben darse algunas condiciones para la adquisición léxica: a) práctica repetitiva, que facilita el paso de los datos a la memoria de larga duración, con la consiguiente procedimentalización y automatización; b) el grado de relevancia respecto a las necesidades comunicativas de los hablantes, teniendo en cuenta que la relevancia comunicativa se correlaciona a su vez con la frecuencia de las palabras en el uso general de la lengua; c) el potencial de adquisición léxica, que se relacionará necesariamente con el número de palabras introducidas en cada unidad de los libros de texto; d) la manera como se ense an las palabras, ya sea explícita o incidentalmente. Para analizar y valorar estos temas, se estudiará el léxico introducido en un libro de texto en lo relativo a la frecuencia, distribución, oportunidades que ofrece para la repetición (que dependerá de la frecuencia con que aparecen las palabras) y naturaleza de las actividades centradas en el léxico. Los resultados de este análisis nos permitirán también valorar si el manual se ajusta y en qué medida a las más recientes investigaciones nacidas de la psicolingüística y la neurolingüística en relación con la adquisición de vocabulario.

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