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On the Cauchy Problem Associated to a Nonequilibrium Bose-Einstein Condensate of Exciton Polaritons
No full textEmbargado hasta 01/01/2100.We study a nonequilibrium Gross--Pitaevskii type system recently proposed to model exciton-polariton condensates. The coupled dispersive-dissipative equations present numerous mathematical challenges, and the known previous methods do not seem to apply in a standard way to study the global dynamics and singularity formation. We consider initial data in Sobolev spaces defined on euclidean (Rd) and periodic (T^d) domains and we prove global in time existence results for small data (in all dimensions) with regularity above the algebra structure under some extra hypotheses. By using Strichartz estimates, we obtain global well-posedness in L^2(R) x L^2(R) (with exponential decay in some physical cases), what cannot be applied to higher dimensions. Furthermore, under some physical assumptions, we show the existence of initial data, in both cases R^d or T^d, such that the corresponding solutions blow up in finite or infinite time, with exponential
rate. Also, using a self-contained approach we also present an interesting result about the existence of initial data with higher regularity, in periodic domains, such that the corresponding solutions either blow up in finite time or have unbounded Sobolev norms with a vanishing dissipation parameter. Finally, we present some numerical simulations in the cases R^d, d = 1, 2, illustrating our results and motivating new research for the system
Stability of mKdV breathers on the half-line
No full textEmbargado hasta 01/01/2100.In this paper we study the stability problem for mKdV breathers on the left half-line. We are able to show that leftwards moving breathers, initially located far away from the origin, are strongly stable for the problem posed on the left half-line, when assuming homogeneous boundary conditions. The proof involves a Lyapunov functional which is almost conserved by the mKdV flow once we control some boundary terms which naturally arise
Ariztimuño Olaso, José de
No full textEmbargado hasta 01/01/2100Entrada en el diccionario biográfico español del escritor y político José de Ariztimuño Olas
La movilidad social en el 'saco interior' de la Bahía de Cádiz, 1910-1935
No full textEmbargado hasta 01/01/210
Estudio sobre la transcripción y la transliteración de la lengua japonesa a la ortografía hispánica
No full textEmbargado hasta 01/01/2100Más allá de las ''someras recomendaciones'' —cita literal— de la última Ortografía de la lengua española (2010) para la hispanización de voces procedentes de lenguas que no emplean el alfabeto latino en su escritura —y a las que tan solo se dedican varias páginas—, ninguna institución oficial ha desarrollado un método de conversión sólido que permita transformar los sonidos y caracteres japoneses al alfabeto hispánico.
Por este motivo, la presente obra propone dos sistemas (uno de transcripción y otro de transliteración) con los que traducir los elementos lingüísticos (visuales u orales) de procedencia japonesa a la escritura del español. Mientras que el sistema de transcripción ha sido concebido para que cualquier hispanohablante adapte fácilmente los vocablos de origen nipón, el sistema de transliteración posibilitará a los especialistas (docentes, traductores o filólogos) representaciones más precisas, tanto de palabras como de unidades superiores.
Asimismo, en este trabajo se describen el sistema de escritura de la lengua japonesa (canyi y silabarios jiragana y catacana) junto con los métodos de transcripción-transliteración comúnmente usados para su aclimatación occidental (Hepburn y Kunrei). Finalmente, este estudio se completa con un análisis histórico-contrastivo sobre la hispanización de los japonesismos (desde la época de los primeros contactos —siglos XVI y XVII— hasta nuestros días)
Growth rate and climatic response of Machaerium scleroxylon in a dry tropical forest in southeastern Santa Cruz, Bolivia
No full textEmbargado hasta 01/01/2100.Machaerium scleroxylon (morado) is an important timber species from the lowland tropical dry forests in Bolivia. We followed a dendrochronological approach to (i) evaluate the responses of radial growth to climatic variables and atmospheric circulation patterns, and (ii) quantify the growth rate in
order to estimate the Minimum Logging Diameter (MLD), age, and optimal cutting rotation. We measured tree-ring width in wood discs taken from ten randomly selected mature individuals. We used previous histological analyses to distinguish and visually crossdate tree rings. Despite the existence of false rings, lenses and wedging rings, the species showed defined annual ring boundaries, thus enabling a tree-ring chronology analysis. Correlations between residual ring-width indices and monthly climaticvariables (temperature and rainfall) and atmospheric circulation patterns (El Niño-Southern Oscillation) index were calculated. Growth showed a significant positive correlation with monthly rainfall and a negative correlation with mean temperature during the late rainy season (i.e. from December up to March). A positive correlation found between the ring width and ENSO indices indicates that the growth of M. scleroxylon was significantly affected by atmospheric circulation patterns. Growth rate is slow in morado, suggesting a MLD of 50 cm and an optimal cutting cycle longer than 40 years depending on each site.Financiado por la Agencia Española de Cooperacion Internacional para el Desarrollo (AECID) a través del proyecto de "Creación del Centro Tecnológico Avanzado Forestal (CTAF) de Santa Cruz de la Sierra, Bolivia
Asparagus (Asparagus officinalis L.) Breeding
No full textEmbargado hasta 01/01/2100Garden asparagus (Asparagus officinalis L.) is an important horticultural plant worldwide. The proposed Center of Origin of this crop comprises Eastern Europe, Caucasus and Siberia. Asparagus officinalis is a monocotyledonous, perennial, diploid, dioecious species with a chromosome number of 2n = 2x = 20. This species belongs to the Asparagus genus which comprises dioecious (Asparagus subgenus) and hermaphroditic species (Myrsiphyllum and Protasparagus subgenera). Polyploidization seems to have played an important role in the evolution of this genus due to a wide range of ploidy levels (2x, 4x, 6x, 8x, 10x,12x), found in inter- and intraspecific taxa. Nowadays, the modern cultivars are diploid hybrids with a narrow genetic base due to their common origin, the Violet Dutch population. The genetic resources of asparagus are an excellent source of genes of interest in breeding programs by using different landraces and wild related species tolerant to biotic and abiotic stresses. These genetic resources may also contribute to develop new varieties with higher bioactive compounds that is an increasing consumer demand. In this chapter, we present an overview of the new advances on genealogy, cytogenetics, genetic resources characterization and conservation, biotechnology and molecular markers linked to sex. Garden asparagus male plants are economically more profitable than females and therefore breeders aim to develop all-male hybrids. Recently, the asparagus reference genome was released and the first saturated genetic map has been obtained. These tools can be used to locate genes and/or QTLs controlling agro-morphic traits and to carry out marker-assisted selection (MAS)
High Prevalence of Probable Sarcopenia in a Representative Sample From Colombia: Implications for Geriatrics in Latin America
No full textEmbargado hasta 01/01/2100.Objectives: The European Working Group on Sarcopenia in Older People 2 (EWGSOP2) recently defined the new concept of probable sarcopenia to help improve screening and prevent future sarcopenia. We investigated the prevalence of probable sarcopenia, defined as weak grip strength, in community-dwelling older Colombian adults, and examined the long-term associated conditions. Design: Cross-sectional study. Setting: Urban and rural Colombian older adults from the “Estudio Nacional de Salud, Bienestar y Envejecimiento (SABE) study”. Participants: 5237 Colombian older adults aged ≥60 years. Measurements: Probable sarcopenia was assessed following the cut-off points for weak grip strength recommended by EWGSOP2 guidelines. Odds ratios (ORs) of the relationship between long-term conditions and probable sarcopenia were determined using logistic regression. Results: The prevalence of probable sarcopenia defined as weak grip strength was 46.5% [95% confidence interval (CI), 45.1-47.8]. Physical inactivity “proxy” (OR 1.35, 95% CI 1.14-1.59); diabetes (OR 1.32, 95% CI 1.11-1.56); and arthritis, osteoarthritis, and rheumatism (OR 1.44, 95% CI 1.25-1.67) were independently associated with probable sarcopenia. Conclusions and Implications: We found that almost half of all the Colombian older adults in our sample had probable sarcopenia. Individuals with physical inactivity, diabetes, arthritis, or osteoarthritis and rheumatism had a higher prevalence of probable sarcopenia. Probable sarcopenia is clinically highly relevant, and several of the factors associated with this condition are potentially preventable, treatable, and reversibl
Machine Learning Methods for Binary and Multiclass Classification of Melanoma Thickness From Dermoscopic Images
No full textEmbargado hasta 01/01/2100Thickness of the melanoma is the most important factor associated with survival in patients with melanoma. It is most commonly reported as a measurement of depth given in millimeters (mm) and computed by means of pathological examination after a biopsy of the suspected lesion. In order to avoid the use of an invasive method in the estimation of the thickness of melanoma before surgery, we propose a computational image analysis system from dermoscopic images. The proposed feature extraction is based on the clinical findings that correlate certain characteristics present in dermoscopic images and tumor depth. Two supervised classification schemes are proposed: a binary classification in which melanomas are classified into thin or thick, and a three-class scheme (thin, intermediate, and thick). The performance of several nominal classification methods, including a recent interpretable method combining logistic regression with artificial neural networks (Logistic regression using Initial variables and Product Units, LIPU), is compared. For the three-class problem, a set of ordinal classification methods (considering ordering relation between the three classes) is included. For the binary case, LIPU outperforms all the other methods with an accuracy of 77.6%, while, for the second scheme, although LIPU reports the highest overall accuracy, the ordinal classification methods achieve a better balance between the performances of all classes
A comparative study of fluorescence and Raman spectroscopy for discrimination of virgin olive oil categories: Chemometric approaches and evaluation against other techniques
No full textEmbargado hasta 01-01-2100Spectroscopic techniques are presented as a reliable and economical alternative for the discrimination of olive oil quality categories. In this work, fluorescence and Raman spectroscopic techniques have been compared by evaluating different characteristics focused on sample preparation and analysis time, as well as classification percentages by chemometric models (PLS-DA) to classify olive oils into three categories: extra virgin (EVOO), virgin (VOO), and lampante (LOO). A statistical evaluation of the quality of the chemometric models was performed by comparing the parameters of sensitivity in terms of the true positive rate (%TPR), specificity (or true negative rate %TNR), and classification error in calibration, cross-validation and prediction. Fluorescence spectroscopy was the screening technique with the best overall accuracy in the ternary models for prediction (78.60%), with higher results than those obtained by Raman (66.03%), the latter being below the average error in the tasting panels. Regarding the classification obtained in binary models (EVOO/Non-EVOO and LOO/Non-LOO), fluorescence spectroscopy continued to present better results than Raman, with classifications of 92.5% and 88.5 % for both models, respectively (Raman obtained percentages of 70.7% and 66.6%). A comparison of the results obtained with confirmation techniques (headspace-gas chromatography-ion mobility spectrometry, HS-GC-IMS) and other spectroscopic techniques (NIR and MIR) studied in previous research was carried out, where it was observed that fluorescence spectroscopy obtained the closest classification percentage to the HS-GC-IMS technique (86.4%) in ternary models. On the other hand, the NIR technique obtained the highest classification percentage in binary models, with 92.6% for EVOO/Non-EVOO and 88.9% for LOO/Non-LOO compared to the value obtained using GC-IMS (95.4 and 86.4 %). Evaluating the rest of the parameters of interest for the olive industry, IR (both NIR and MIR) was the most interesting technique because it is a cheap, simple sensor with fast chemometric treatments and is environmentally-friendly. The results of this comparative study can be used to provide solutions and alternatives for applying new analytical strategies to support the work of tasting panels