Geographical and environment-related variations of essential oils in isolated populations of Thymus richardii Pers. in the Mediterranean basin

Composition of essential oils of different populations of Thymus richardii grex of six localities from Bosnia-Herzegovina (Konjic, Borci), Spain (Majorca, Ibiza, Valencia) and Italy (Marettimo, Sicily) were determined by GC/FID and GC/MS. The main constituents in most of the samples were aromatic monoterpenes corresponding to non-phenolic cyclic compounds (p-cymene, gamma-terpinene). The highest monoterpene concentrations were found in the Bosnian samples (70%), and the lowest in samples from the Balearic Islands ( 50%) in samples from Majorca with beta-bisabolene (>40%) being the principal constituent. Discriminant analysis (LDA) shows the differentiation of two chemotypes: A (phenol chemotype), with p-cymene and gamma-terpinene as characteristic compounds and B, with beta-bisabolene and carvacrol, as major and significative compounds. The occurrence of the chemotypes was related to summer positive precipitation and to deep of soils.Llorens, L.; Llorens Molina, JA.; Agnello, S.; Boira Tortajada, H. (2014). Geographical and environment-related variations of essential oils in isolated populations of Thymus richardii Pers. in the Mediterranean basin. Biochemical Systematics and Ecology. 56:246-254. doi:10.1016/j.bse.2014.05.0072462545

Seasonal variations in essential oil of aerial parts and roots of an Artemisia absinthium L. population from a Spanish area with supramediterranean climate (Teruel, Spain)

[EN] The seasonal variation of essential oil composition of aerial parts and roots of Artemisia absinthium L. has been investigated. It was obtained from individuals growing wild in Teruel (Spain) by means of hydrodistillation (aerial parts) or simultaneous distillation extraction (roots), and analyzed by GC/MS and GC/FID. Results showed a predominance of oxygenated monoterpenes (81.4-89.1%) in aerial parts; mainly (Z)-epoxyocimene (49.3-71.5%), (Z)-chrysanthemyl acetate (7.6-18%) and linalool (0.7-10.4%). In spite of the high intrapopulational variability, significant variations were observed for these three compounds. Root essential oil composition showed a high amount of hydrocarbon monoterpenes (43.8-55.1%) and monoterpenic esters (36.6-41.5%) with a noticeable seasonal stability except for some allelopathic oxygenated monoterpenes. As A. absinthium is a typical invasive species, knowing the seasonal variations of these compounds may be a first step to study their release in soil as a source for natural herbicides.Llorens Molina, JA.; Vacas González, S. (2015). Seasonal variations in essential oil of aerial parts and roots of an Artemisia absinthium L. population from a Spanish area with supramediterranean climate (Teruel, Spain). Journal of Essential Oil Research. 27(5):395-405. doi:10.1080/10412905.2015.1043400S395405275Ariño, A., Arberas, I., Renobales, G., Arriaga, S., & Dominguez, J. B. (1999). Essential Oil ofArtemisia absinthiumL. from the Spanish Pyrenees. Journal of Essential Oil Research, 11(2), 182-184. doi:10.1080/10412905.1999.9701105Abad, M. J., Bedoya, L. M., Apaza, L., & Bermejo, P. (2012). The Artemisia L. Genus: A Review of Bioactive Essential Oils. Molecules, 17(3), 2542-2566. doi:10.3390/molecules17032542Blagojević, P., Radulović, N., Palić, R., & Stojanović, G. (2006). Chemical Composition of the Essential Oils of Serbian Wild-GrowingArtemisia absinthiumandArtemisia vulgaris. Journal of Agricultural and Food Chemistry, 54(13), 4780-4789. doi:10.1021/jf060123oRezaeinodehi, A., & Khangholi, S. (2008). Chemical Composition of the Essential Oil of Artemisia absinthium Growing Wild in Iran. Pakistan Journal of Biological Sciences, 11(6), 946-949. doi:10.3923/pjbs.2008.946.949Carnat, A.-P., Madesclaire, M., Chavignon, O., & Lamaison, J.-L. (1992). cis-Chrysanthenol, A Main Component in Essential Oil ofArtemisia absinthiumL. Growing in Auvergne (Massif Central), France. Journal of Essential Oil Research, 4(5), 487-490. doi:10.1080/10412905.1992.9698115Lopes-Lutz, D., Alviano, D. S., Alviano, C. S., & Kolodziejczyk, P. P. (2008). Screening of chemical composition, antimicrobial and antioxidant activities of Artemisia essential oils. Phytochemistry, 69(8), 1732-1738. doi:10.1016/j.phytochem.2008.02.014Basta, A., Tzakou, O., Couladis, M., & Pavlović, M. (2007). Chemical Composition ofArtemisia absinthiumL. from Greece. Journal of Essential Oil Research, 19(4), 316-318. doi:10.1080/10412905.2007.9699291Ariño, A., Arberas, I., Renobales, G., Arriaga, S., & Domínguez, J. B. (1999). Seasonal Variation in Wormwood (Artemisia absinthiumL.) Essential Oil Composition. Journal of Essential Oil Research, 11(5), 619-622. doi:10.1080/10412905.1999.9701226Goel, D., Goel, R., Singh, V., Ali, M., Mallavarapu, G. R., & Kumar, S. (2007). Composition of the essential oil from the root of Artemisia annua. Journal of Natural Medicines, 61(4), 458-461. doi:10.1007/s11418-007-0175-2Mirjalili, B. F., Meybody, M. H. H., Ardakani, M. M., Rustaiyan, A., Ameri, N., Masoudi, S., & Bamoniri, A. (2006). Chemical Composition of the Essential Oil from Aerial Parts, Leaves, Flowers and Roots ofArtemisia persicaBoiss. from Iran. Journal of Essential Oil Research, 18(5), 544-547. doi:10.1080/10412905.2006.9699162Jassbi, A. R., Zamanizadehnajari, S., & Baldwin, I. T. (2010). Phytotoxic Volatiles in the Roots and Shoots of Artemisia tridentata as Detected by Headspace Solid-phase Microextraction and Gas Chromatographic-mass Spectrometry Analysis. Journal of Chemical Ecology, 36(12), 1398-1407. doi:10.1007/s10886-010-9885-0De Almeida, L. F. R., Frei, F., Mancini, E., De Martino, L., & De Feo, V. (2010). Phytotoxic Activities of Mediterranean Essential Oils. Molecules, 15(6), 4309-4323. doi:10.3390/molecules15064309Zahed, N., Hosni, K., Ben Brahim, N., Kallel, M., & Sebei, H. (2010). Allelopathic effect of Schinus molle essential oils on wheat germination. Acta Physiologiae Plantarum, 32(6), 1221-1227. doi:10.1007/s11738-010-0492-zYoung, G. P., & Bush, J. K. (2009). Assessment of the Allelopathic Potential of Juniperus ashei on Germination and Growth of Bouteloua curtipendula. Journal of Chemical Ecology, 35(1), 74-80. doi:10.1007/s10886-008-9585-1Not Available, N. A., & Duke, S. O. (2003). Ecophysiological aspects of allelopathy. Planta, 217(4), 529-539. doi:10.1007/s00425-003-1054-zAbrahim, D., Braguini, W. L., Kelmer-Bracht, A. M., & Ishii-Iwamoto, E. L. (2000). Journal of Chemical Ecology, 26(3), 611-624. doi:10.1023/a:100546790329

La caracterización del ambiente de aprendizaje en un laboratorio de química general mediante métodos de investigación social

Desde una crítica al paradigma proceso-producto, que asume la causalidad entre el diseño del proceso de aprendizaje y su desarrollo, consideramos la caracterización de los ambientes de aprendizaje un requisito para la evaluación de innovaciones educativas. En este trabajo han sido incorporados métodos de la investigación social como los inspirados en la Teoría Fundamentada, a la caracterización del ambiente de aprendizaje en un contexto experimental. Mediante dichos métodos se ha llevado a cabo un estudio de caso en el que han sido analizadas las preguntas formuladas en el laboratorio y las reflexiones reflejadas en sus cuadernos por los estudiantes, con objeto de proponer un marco conceptual para la evaluación de dichos ambientes de aprendizaje. Los resultados justifican el uso de tales métodos, al ser notablemente contradictorios con los procedentes de la aplicación de un cuestionario basado en el conocido Science Laboratory Environment Inventory.From a critical view point of process-product paradigm, which accepts a causal relationship between learning process design and its classroom development, the characterization of Learning Environments as requirement for educational innovations assessment is considered. In this paper, research methods from Social Sciences as those inspired in the Grounded Theory have been applied to experimental learning environments. Students generated questions during laboratory sessions and self-reports have been analyzed by means of a case study in order to propose a framework to assess these learning environments. The results justify the use of suggested methodology since they are significantly contradictory with the ones from a questionnaire based on the well known Science Laboratory Environment Inventory

Essential oil composition of berries of Juniperus oxycedrus L. ssp. oxycedrus according to their ripening stage

[EN] Some essential oils (EOs) can be extracted from berries of different species, and their composition depends on their maturation level. In this work, these parameters were correlated forJuniperus oxycedrusL ssp.oxycedrus. For this purpose, a classification method based on the CIE L*a*b* colour measurement was applied. Once the samples were classified, they were subjected to simultaneous distillation extraction and gas chromatography (GC/FID and GC/MS). Hydrocarbon monoterpenes constituted the major fraction (42.8-89.8%), mainly represented by -pinene (30.1-66.4%) and myrcene (6.1-34.8%). Hydrocarbon sesquiterpenes accounted for 4.0-26.4%, with germacrene-D (0.2-16.9%) as the major component. The discriminant analysis proved that CIE L*a*b* implementation was useful to classify the ripening stage. Regarding the EO composition, significant differences were observed in myrcene, camphor and germacrene-D, as well as in the grouped oxygenated and hydrocarbon terpenoids. In general, a progressive increase in oxygenated compounds was noted over the maturation process.Llorens Molina, JA.; Ygueravide, B.; Vacas, S. (2019). Essential oil composition of berries of Juniperus oxycedrus L. ssp. oxycedrus according to their ripening stage. Journal of Essential Oil Research. 31(4):276-285. https://doi.org/10.1080/10412905.2019.1583140S27628531

Registro multimodal de mamografías: resonancia magnética y rayos-x

Solves Llorens, JA. (2014). Registro multimodal de mamografías: resonancia magnética y rayos-x [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/38940TESI

Los informes de laboratorio. Su contribución al desarrollo y evaluación de las competencias transversales

[EN] The laboratory learning activities can constitute a suitable educational framework for generic competencies development such as application and practical thinking, analysis and solving problem, teamwork and leadership, etc. For this reason, a key element to evaluate its acquisition and to define the control points can be the assessment of laboratory work, provided that it goes beyond the only manipulative skills or the influence on theoretical knowledge acquisition. It requires a deep methodological change, both concerning its purpose, organization and design and used assessment tools. In this context, to incorporate critical reflection activities to laboratory reports can provide a valuable information. The results of analysis and encoding of students’ reflections from these activities in a 1st course of basic chemistry in Science and Food Technology studies have been discussed in this communication. From these results, several guidelines for development and assessment of generic competencies by means of laboratory work activities have been proposed[ES] Las actividades de aprendizaje en el laboratorio pueden constituir un marco idóneo para el desarrollo de competencias transversales tales como “aplicación y pensamiento práctic”, “análisis y resolución de problemas” o “trabajo en equipo y liderazgo”, etc. Por este motivo, un elemento clave para evaluar su adquisición y definir los puntos de control puede ser la evaluación del trabajo de laboratorio, siempre y cuando ésta vaya más allá de lo puramente manipulativo o de la influencia en la adquisición de conocimientos teóricos. Ello exige un profundo cambio metodológico, tanto en su finalidad, organización y diseño como en los instrumentos de evaluación utilizados. En este contexto, la incorporación a los informes de laboratorio de actividades de reflexión crítica puede proporcionar una información valiosa. En esta comunicación se discuten los resultados del análisis y codificación de las reflexiones obtenidas de estas actividades en la asignatura Fundamentos de Química, en un primer curso del Grado de Ciencia y Tecnología de Alimentos. A partir de estos resultados se propone un conjunto de orientaciones para el desarrollo y evaluación de las competencias transversales a través del trabajo de laboratorio.Llorens Molina, JA. (2015). Los informes de laboratorio. Su contribución al desarrollo y evaluación de las competencias transversales. En In-Red 2015 - CONGRESO NACIONAL DE INNOVACIÓN EDUCATIVA Y DE DOCENCIA EN RED. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2015.2015.1618OC

Análisis de la densidad de mama asistido por ordenador

Estudio del estado actual del análisis de la densidad de mama.Solves Llorens, JA. (2009). Análisis de la densidad de mama asistido por ordenador. http://hdl.handle.net/10251/14555Archivo delegad

Algunas propuestas para la contextualización de las prácticas de laboratorio.

Peer Reviewe

La evaluación formativa: un análisis desde la perspectiva de los estudiantes

[EN] Results from weekly online self-assessment activities are shown in this work. It has been developed over two consecutive years in an introductory organic chemistry course. These activities were also complemented by the availability of short video recording lessons (polimedia) related to key issues of subjectmatter content. The objectives of this work were mainly to know the students’ opinions concerning the usefulness of these educational resources, as well as some aspects of their design and mode of use. Likewise, self-assessment practice is also related to students’ performance in term final examination. The results showed a strongly positive perception of both resources although they also suggest modifying some aspects of their design and mode of use, such as their timing and duration of their availability.[ES] En este trabajo se presentan los resultados de la aplicación de actividades deautoevaluación online semanales. Estas han sido desarrolladas a lo largo dedos años consecutivos en un curso introductorio de química orgánica.Dichas actividades vienen también complementadas por la disponibilidad degrabaciones en video de corta duración (polimedia) centradas en aspectosclave del contenido. Los objetivos de este estudio son principalmente conocerlas opiniones de los estudiantes acerca de la utilidad de estos recursos, asícomo de algunos aspectos de su diseño y utilización. Asimismo, también serelaciona la práctica de la autoevaluación con el rendimiento en el examende la asignatura. Los resultados muestran una percepción claramentepositiva de estos recursos, aunque también aconsejan modificar algunosaspectos de su diseño y modo de utilización, tal como el momento en que seutilizan y el tiempo de disponibilidad.Llorens Molina, JA. (2017). La evaluación formativa: un análisis desde la perspectiva de los estudiantes. En In-Red 2017. III Congreso Nacional de innovación educativa y de docencia en red. Editorial Universitat Politècnica de València. 1099-1111. https://doi.org/10.4995/INRED2017.2017.6712OCS1099111