1,876 research outputs found
Synthesis of New Analogues of the Bengamides: Peptidyl Bengamides and Molecular Probes
Isolated from sponges of the Jaspidae family, first members where discovered in 1986. The bengamides represent an interesting and unprecedented family of natural products that displayed striking antitumor activities [1]. The recognition of these natural products as antiangiogenic compounds, in virtue to their inhibition of methionine aminopeptidases, prompted intense research activities in the chemical and biological fields. In fact, the total synthesis of the natural products, together with an extensive variety of analogues, has been reported in the literature [2]. Particularly, we have recently developed a new synthetic methodology which allowed rapid and efficient access to the natural bengamide E (1), together with a wide library of analogues of which the cyclopentyl analogue 2 was identified as a more potent antitumor compound with respect to its natural congener [3]. As continuation of these synthetic efforts, with the objective of identifying new potent and promising analogues, we wish to report our recent synthetic studies directed to the synthesis of new bengamide analogues, featured by the replacement of the caprolactam fragment by a peptidyl residue (compounds type 3). On the other hand, in order to gain insight into the mechanism of the biological action of the bengamides, we describe the preparation of the N-alkyl derivatives 4 and 5, which represent interesting molecules that could be employed as suitable molecular probes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Preliminary results from characterization of the Iberian Peninsula sturgeon based on analysis of the mtDNA cytochrome b
Historically, the Atlantic sturgeon Acipenser sturio L., 1758 was considered the only sturgeon species that inhabited rivers of the Iberian Peninsula. Nevertheless, in a recent paper, Garrido- Ramos et al. (1997) identified specimen EBD 8174 (museum collection of the Doñana Biological Station, Spain), from the Guadalquivir River, as the Adriatic sturgeon Acipenser naccarii Bonaparte, 1836, suggesting that both A. sturio and A. naccarii could be native to Spain. To test this theory, we compared partial mitochondrial cytochrome b (cyt b) gene sequences obtained from museum specimens of A. sturio that originated from the Iberian Peninsula, the Adriatic and the North Sea, as well as from live individuals of the Gironde River population in France. Specimens of A. naccarii and of the Siberian sturgeon Acipenser baerii Brandt, 1869 from fish farms were also included in the study. DNA from museum specimens was successfully amplified using the protocol of France and Kocher (1996) for DNA extraction from formalin-fixed and ethanol-preserved samples. Phylogenetic analysis was performed on partial cyt b gene sequences (over 402-bp and 245-bp). We identified specimen EBD 8174 as A. sturio, confirming the opinion that A. sturio is the only sturgeon species of the Iberian Peninsula. Further molecular analyses of museum specimens are needed for a description of the historical intraspecies genetic variation within A. sturio. This information is crucial for any future recovery plan for this species. Our comparison also showed interspecies sequence divergence ranging from 6.91% (A. sturio/A. naccarii) to 7.43% (A. sturio/A. baerii).Históricamente, el esturión atlántico Acipenser sturio L., 1758 ha sido considerado la única especie de esturión que vive en los ríos de la península Ibérica, siendo así demostrado por múltiples estudios morfológicos recientes. Sin embargo, un trabajo reciente identificó el ejemplar del río Guadalquivir EBD 8174 como Acipenser naccarii Bonaparte, 1836, sugiriendo que ambas especies de esturión podrían ser nativas de España. Para comprobar esta nueva teoría, se han analizado las secuencias del gen citocromo b mitocondrial en muestras de esturión atlántico preservadas en varios museos procedentes de la península Ibérica, el mar Adriático y el mar del Norte, así como material fresco del río Garona. Además, se han estudiado con fines comparativos varias muestras de A. naccarii y Acipenser baerii Brandt, 1869 procedentes de piscifactorías. Las muestras de museos fueron amplificadas con éxito usando un protocolo específico utilizado para material fijado en formol y preservado en alcohol. La muestra de esturión de España (EBD 8174) fue identificada como A. sturio. Este resulta do confirma que A. sturio es la única especie de esturión en la península Ibérica. De cualquier manera, antes de abordar los planes de recuperación, sería necesario realizar análisis moleculares complementarios para describir las posibles variaciones genéticas existentes entre poblaciones. La comparación de las secuencias de citocromo b de A. sturio con A. naccarii y A. baerii mostró valores de divergencia de 6,91% y 7,43% respectivamente.Instituto Español de Oceanografí
Effect of Location, Clone, and Measurement Season on the Propagation Velocity of Poplar Trees Using the Akaike Information Criterion for Arrival Time Determination
The purchase price of any forest plantation depends on the quality of its raw wood, and
specifically, variables such as density, orientation of the fibers, bending strength, and bending MoE
(Modulus of Elasticity). The elastic waves propagation velocity has become one of the most popular
parameters to evaluate the wood in standing trees. This study had two objectives: (1) Show how
this velocity is clearly affected by the clone, the location of the crop, and the measurement season of
poplar crops; and (2) apply the Akaike information criterion to determinate the arrival time of the
waves, on the basis of the entropy of the signals recorded by the piezoelectric sensors placed on the
trunk of the tree.This work has been possible due to the financial support of the COMPOP_Timber project
“Desarrollo de productos de ingeniería elaborados a base de tablones y chapas de chopo con inserciones de
material compuesto para su uso en construcción”, BIA2017-82650-R. The authors thank to Antonio Aguilar and
Chihab Abarkane, for his help during measurements in field, and Esther Merlo from MADERAS PLUS, for the
analysis of results and methods
Seeing Andalucia’s Late Gothic heritage through GIS and Graphs
This study discusses the methodology used in The Digital model of Andalusia's Late Gothic Heritage project to develop new models of heritage interpretation through the application of GIS and Graph visualization to provide new perspectives of Andalusia's heritage by considering social, political, economic and cultural evolutions. Given the special period context considered, late 15th and early 16th centuries, the project used a variety of sources to relate heterogeneous historical data on different subjects in order to create a historical spatial database and to respond questions such as: How was the construction process in Andalusia between 1433 and 1560? What period and region had more constructive activity? How did the opening of the Andalusia´s eastern border modify the dynamism of the territory? What features are more common in each time period? What professionals have worked together on a building or quarry? Is this reflected in the architectural language produced?
Psychometric properties of the Valuing Questionnaire in a Spaniard sample and factorial equivalence with a Colombian sample
Background. The Valuing Questionnaire (VQ) is considered as one of the most psychometrically robust instruments to measure valued living according to the acceptance and commitment therapy model. It consists of 10 items that are responded to on a 7-point Likert-type scale and has two factors: Progression and Obstruction. The Spanish version of theVQshowed good psychometric properties in Colombian samples. However, there is no evidence of the psychometric properties of the VQ in Spaniard samples. This
study aims to analyze the validity of the VQ in a large Spaniard sample and analyze the measurement invariance with a similar Colombian sample.
Method. The VQ was administered to a Spaniard sample of 846 adult participants from general online population. Cronbach's alpha and McDonald's omega were computed to analyze the internal consistency of the VQ. The fit of the VQ's two-factor model was tested through a confirmatory factor analysis with a robust maximum likelihood (MLR) estimation method. Afterward, we analyzed the measurement invariance across
countries and gender. Convergent construct validity was analyzed with a package of questionnaires that evaluated experiential avoidance (Acceptance and Action Questionnaire-II, AAQ-II), emotional symptoms (Depression Anxiety and Stress Scale-21, DASS-21), life satisfaction (Satisfaction with Life Scale, SWLS), and cognitive fusion (Cognitive Fusion Questionnaire, CFQ).
Results. The internal consistency across samples was adequate (alphas and omegas were .85 for VQ-Progress and .84 for VQ-Obstruction). The two-factor model obtained a good fit to the data (RMSEA D 0.073, 90% CI [0.063, 0.083], CFI D 0.98, NNFI D 0.97, and SRMR D 0.053). The VQ showed strict invariance across countries and gender and showed theoretically coherent correlations with emotional symptoms, life satisfaction, experiential avoidance, and cognitive fusion. In conclusion, the Spanish version of the
VQ demonstrated good psychometric properties in a large Spaniard sample
Supercritical carbon dioxide extraction of lipids from Eucalyptus globulus wood
7 páginas, 2 tablas, 1 gráfico, 10 referencias.Various typical lipid components of wood extractives have been isolated from Eucalyptus globulus wood by supercritical carbon dioxide modified with methanol. The influence of various extraction parameters on the yield and qualitative composition of the extracts have been studied.
The extracts were analyzed by gas chromatography–mass spectrometry and compared with those obtained by Soxhlet extraction with acetone, the standard method for the determination of wood extractives. The qualitative and quantitative results obtained by both methods were in good
agreement. The experimental planning to asses the influence of pressure, temperature and percentage of methanol and their interactions on the extraction efficiency was carried out with a factorial design, followed by multiple linear regression algorithm.This research has been supported by the projects PB95-0079 (Spanish CICYT) and FAIR CT95-0560 (UE-Commission).Peer reviewe
Supercritical carbon dioxide extraction of lipids from Eucalyptus globulus wood
7 páginas, 2 tablas, 1 gráfico, 10 referencias.Various typical lipid components of wood extractives have been isolated from Eucalyptus globulus wood by supercritical carbon dioxide modified with methanol. The influence of various extraction parameters on the yield and qualitative composition of the extracts have been studied.
The extracts were analyzed by gas chromatography–mass spectrometry and compared with those obtained by Soxhlet extraction with acetone, the standard method for the determination of wood extractives. The qualitative and quantitative results obtained by both methods were in good
agreement. The experimental planning to asses the influence of pressure, temperature and percentage of methanol and their interactions on the extraction efficiency was carried out with a factorial design, followed by multiple linear regression algorithm.This research has been supported by the projects PB95-0079 (Spanish CICYT) and FAIR CT95-0560 (UE-Commission).Peer reviewe
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