226 research outputs found

    Análisis de componentes principales sobre datos multiespectrales “Landsat-TM” e interpretación de cubiertas vegetales en las Sierras de Tejeda y Almijara

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    The simultaneous consideration of all reflectance bands during image processing of multiespectral, remotely-sensed data, usually involves a very large volume of data to handle. However, this increase in data volume is not followed by a similar increment in the volume of additional information that is accounted for, which is due to the existence of a very high correlation between reflectance bands. In this paper we report the results of applying a multivariate statistical tool (Principal Component Analysis, PCA) to the first four reflectance bands of a LANDSAT «Thematic Mapper» image of Sierra de Tejeda and Sierra de Almijara (Southern Spain). The aim of this analysis was to achieve a reduction in the volume of data to handle during image processing while avoiding a significant loss of information. The first two principal components resulting from the analysis accounted for more than 99% of the total variance in the original data set. The image obtained through the first principal component transform could be interpreted as a weighed-sum image of all reflectance bands (thus similar to a black and white panchromatic photograph with an extension into the infrared wavelength). This image showed optimum feasibility for the interpretation of geological, hydrological and topographic features of the study area. The second principal component transform was able to extract the «green» signal of the vegetation canopy from the complex set of multiespectral data. Relief features (i.e., areas of shadow in north-facing slopes versus well-illuminated, south-facing slopes) did not appear in the resulting image (these features had already been accounted for by the first principal component), which is an advantage when studying vegetation cover in areas with steep relief. A strong possitive correlation was found between the second PCA image and those resulting from the application of standard spectral vegetation indexes (RVI and NDVI). The initial assesment of the images has shown that severe deaforestation is undergoing in the area. About 30% of the study area was occupied by bare soils. This figure went up to 85% if areas with scattered vegetation were also included. Multivariate analysis has confirmed as a valuable tool for the interpretation of multiespectral satellite data from the study area. Eventually, the obtention of a principal component transform based on the selective sampling of appropiate subsets of pixels from the area would provide of algorithms that applied to the entire set in multitemporal images could, for instance, be used to monitor long-term and large-scale deaforestation processes in the region.La consideración simultánea de todas las bandas de reflectancia en el análisis de imágenes multiespectrales teledetectadas, representa un incremento en el volumen de datos a procesar proporcionalmente mucho mayor que la ganancia real de información que se consigue, lo que se debe a la elevada correlación existente entre aquéllas. En este trabajo se aplica un análisis de componentes principales a datos multiespectrales Landsat TM de las Sierras de Tejeda y Almijara, con el objeto de sumarizar los mismos sin una pérdida significativa de información. Los dos primeros componentes principales obtenidos recogieron más del 99% de la varianza total original. La imagen que se obtuvo a partir del primer componente principal representaba, aproximadamente, una suma ponderada de todas las intensidades de reflectancia en las distintas bandas consideradas (análoga, por tanto, a una fotografía en blanco y negro con una extensión en el infrarrojo) y mostró una interpretabilidad óptima para aspectos de topografía-relieve, red de drenaje y tipos litológicos. La imagen resultante del segundo componente principal (ya sin efecto de relieve) mostró la intensidad de señal "verde" del dosel vegetal y se correlacionaba significativamente con las obtenidas de la aplicación de índices espectrales de vegetación (RVI, NDVI) a los datos originales. El análisis preliminar de las imagenes indica problemas de deforestación grave en la zona (casi un 30% de la superficie con suelos desnudos, y hasta un 85% si se incluyen areas con vegetación dispersa). El análisis multivariado se ha confirmado como una herramienta útil para la interpretación de imágenes teledetectadas de la zona de estudio. Eventualmente, la obtención de la transformación de componentes principales por medio de un muestreo selectivo, proveería de algoritmos de transformación para los datos multiespectrales con los que se podría, por ejemplo, hacer un seguimiento de cambios en procesos tales como la deforestación

    Importancia de la embolización preoperatoria en el tratamiento del quiste óseo aneurismático: Presentación de un caso clínico

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    Se describe el tratamiento de un quiste óseo aneurismático localizado en el raquis dorsal, en un niño de 8 años de edad. El quiste óseo aneurismático es una lesión benigna y a menudo extremadamente vascular. En la columna puede causar extensa destrucción ósea y compromiso de las estructuras neurales. Se demuestra el valor de la embolización preoperatoria reduciendo la vascularización y permitiendo su extirpación quirúrgica total.I n this report, th e managemen t o f a n aneurysma l bon e cyst i n th e thoraci c spin e o f an 8 year s ol d bo y is described . Aneurysma l bon e is a histologicall y benig n lesio n tha t is ofte n extremel y vascular . I n th e spine , it ca n caus e extensiv e bon e destructio n an d compress neura l structures. Th e valu e o f preoperativ e embo - lizatio n t o reduc e vascularity , allowin g tota l excisio n is demonstrated

    Bullying of individuals with cleft lip and palate frequency and preventive procedures

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    Purpose: The purpose of this study was to verify the prevalence of bullying among children and adolescents, the consequences on the social development and educational process, evaluating the public policies for prevention or punishment of this negative behavior. Methods: The study group comprised 121 patients with cleft lip and palate in the process of rehabilitation in a single center from both sexes with age varying from 6 to 35 years. The control group comprised 121 siblings of these patients born without cleft lip and palate. A questionnaire with objective questions on bullying and its consequences was answered by one of the parents or tutors. Preventive procedures were discussed with the parents. The prevalence of bullying was calculated for each group. Intergroup comparisons were performed using Chi-square and Fisher exact tests (p<0.05). Results: Bullying was reported as a frequent occurrence in the group of individuals with cleft lip and palate (50.4%). A higher frequency of bullying against individuals with CLP was found compared to the group of siblings without CLP (22.3%) (p<0.01). The most common type of bullying was oral offense (78.7%) followed by physical with oral offense (19.7%). The school was the most frequent place of bullying occurrence (86.9%). Most of the parents/tutor reported the desire for educational procedures and public policies to prevent this type of aggression. Conclusions: Bullying was more frequent among individuals with cleft lip and palate in comparison with noncleft individuals. Public policies should be implemented for educating and preventing this violence against human being

    Transcriptome Analysis and Intraspecific Variation in Spanish Fir (Abies pinsapo Boiss.)

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    Spanish fir (Abies pinsapo Boiss.) is an endemic, endangered tree that has been scarcely investigated at the molecular level. In this work, the transcriptome of Spanish fir was assembled, providing a large catalog of expressed genes (22,769), within which a high proportion were full-length transcripts (12,545). This resource is valuable for functional genomics studies and genome annotation in this relict conifer species. Two intraspecific variations of A. pinsapo can be found within its largest population at the Sierra de las Nieves National Park: one with standard green needles and another with bluish-green needles. To elucidate the causes of both phenotypes, we studied different physiological and molecular markers and transcriptome profiles in the needles. “Green” trees showed higher electron transport efficiency and enhanced levels of chlorophyll, protein, and total nitrogen in the needles. In contrast, needles from “bluish” trees exhibited higher contents of carotenoids and cellulose. These results agreed with the differential transcriptomic profiles, suggesting an imbalance in the nitrogen status of “bluish” trees. Additionally, gene expression analyses suggested that these differences could be associated with different epigenomic profiles. Taken together, the reported data provide new transcriptome resources and a better understanding of the natural variation in this tree species, which can help improve guidelines for its conservation and the implementation of adaptive management strategies under climatic change.This research was funded by research projects “Genómica funcional del pinsapo” and “Genómica del pinsapo: Estudios estructurales y funcionales” (grant numbers UMA18-FEDERJA-018 and P20-00507-R, funded by Junta de Andalucía, PAIDI) and “Modulators of adaptive capacity to climate change in forests: integration from the landscape to the gene/transcriptome in relict mountain conifers (CoMoReAdapt)” (grant number CGL2013-48843-C2-1-R, funded by the Spanish Ministry of Economy and Competitiveness, National Program for R + D+i). Partial funding for open access charge: Universidad de Málag

    Experiencias prácticas y competencias profesionales desde la docencia de Ecología Forestal

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    En esta comunicaci&oacute;n se desarrollan las actividades docentes llevadas a cabo con los alumnos de la asignatura optativa Ecolog&iacute;a Forestal de la Licenciatura de Biolog&iacute;a en la Universidad de Ja&eacute;n, entre los a&ntilde;os 2003 a 2010. Durante este periodo se ha desarrollado la parte pr&aacute;ctica de la asignatura con un enfoque aplicado para el desarrollo de capacidades profesionales en el &aacute;mbito de la ecolog&iacute;a forestal y la gesti&oacute;n de ecosistemas forestales, incluyendo una revisi&oacute;n metodol&oacute;gica para incorporar t&eacute;cnicas y herramientas &uacute;tiles en actividades profesionales propias de un Bi&oacute;logo

    Dissociation of a Strong Acid in Neat Solvents: Diffusion Is Observed after Reversible Proton Ejection Inside the Solvent Shell

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    This is the peer-reviewed version of the following article: The Journal of Physical Chemistry B 2013, 117, 14065–14078, DOI: 10.1021/jp4042765, which has been published in final form at https://pubs.acs.org/doi/abs/10.1021/jp4042765. This article may be used for non-commercial purposes onlyStrong-acid dissociation was studied in alcohols. Optical excitation of the cationic photoacid N-methyl-6-hydroxyquinolinium triggers proton transfer to the solvent, which was probed by spectral reconstruction of picosecond fluorescence traces. The process fulfills the classical Eigen–Weller mechanism in two stages: (a) solvent-controlled reversible dissociation inside the solvent shell and (b) barrierless splitting of the encounter complex. This can be appreciated only when fluorescence band integrals are used to monitor the time evolution of the reactant and product concentrations. Band integrals are insensitive to solvent dynamics and report relative concentrations directly. This was demonstrated by first measuring the fluorescence decay of the conjugate base across the full emission band, independently of the proton-transfer reaction. Multiexponential decay curves at single wavelengths result from a dynamic red shift of fluorescence in the course of solvent relaxation, whereas clean single exponential decays are obtained if the band integral is monitored instead. The extent of the shift is consistent with previously reported femtosecond transient absorption measurements, continuum theory of solvatochromism, and molecular properties derived from quantum chemical calculations. In turn, band integrals show clean biexponential decay of the photoacid and triexponential evolution of the conjugate base in the course of the proton transfer to solvent reaction. The dissociation step follows the slowest stage of solvation, which was measured here independently by picosecond fluorescence spectroscopy in five aliphatic alcohols. Also, the rate constant of the encounter-complex splitting stage is compatible with proton diffusion. Thus, for this photoacid, both stages reach the highest possible rates: solvation and diffusion control. Under these conditions, the concentration of the encounter complex is substantial during the earliest nanosecondWe thank the Spanish Government and the European Regional Development Fund (grant nos. CTQ2010-17835, CTQ2010-17026, and CTQ2011-29311-C02-01) and the Xunta de Galicia (grants nos. CN 2012/314, 2012-PG237, GPC2013/052 and INCITE09 314 252 PR) for financial support of our work. J.L.P.L. thanks the Spanish Ministry of Economy and Competitiveness for funding through the Ramon y Cajal ́ Programm 2009. M.V. and C.C.B. thank the Spanish Government for funding through the FPU program. A. B. thanks the Segundo Gil Dávila Foundation for financial supportS

    Effects of Resistance Exercise on Endothelial Progenitor Cell Mobilization in Women

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    This study aimed to determine the effect of a single bout of resistance exercise at different intensities on the mobilization of circulating EPCs over 24 hours in women. In addition, the angiogenic factors stromal cell-derived factor 1 (SDF-1α), vascular endothelial growth factor (VEGF), hypoxia-inducible factor 1-alpha (HIF-1α) and erythropoietin (EPO) were measured as potential mechanisms for exercise-induced EPCs mobilization. Thirty-eight women performed a resistance exercise session at an intensity of 60% (n = 13), 70% (n = 12) or 80% (n = 13) of one repetition maximum. Each session was comprised of three sets of 12 repetitions of four exercises: bench press, dumbbell curl, dumbbell squat, and standing dumbbell upright row. Blood was sampled at baseline and immediately, 6 hours, and 24 hours post-exercise. Circulating EPC and levels of VEGF, HIF-1α and EPO were significantly higher after exercise (P \u3c 0.05). The change in EPCs from baseline was greatest in the 80% group (P \u3c 0.05), reaching the highest at 6 hours post-exercise. The change in EPCs from baseline to 6 hours post-exercise was correlated with the change in VEGF (r = 0.492, P = 0.002) and HIF-1α (r = 0.388, P = 0.016). In general, a dose-response relationship was observed, with the highest exercise intensities promoting the highest increases in EPCs and angiogenic factors

    Evidence of telomere attrition and a potential role for DNA damage in systemic sclerosis

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    [Background]: To investigate the role of cell senescence in systemic sclerosis (SSc), we analyzed telomere shortening (TS) in SSc patients and the effect of targeting DNA damage in the bleomycin model of skin fibrosis. [Results]: Telomere length (TL) in blood leukocytes of 174 SSc patients and 68 healthy controls was measured by Southern blot, and we found shorter age-standardized TL in SSc patients compared to healthy controls. TL was shorter in SSc patients with ILD compared to those without ILD and in anti-topoisomerase I positive compared to anti-centromere positive patients. To analyze the potential role of DNA damage in skin fibrosis, we evaluated the effects of the DNA protective GSE4 peptide in the bleomycin mouse model of scleroderma and the fibrotic response of cultured human dermal fibroblasts. Administration of GSE4-nanoparticles attenuated bleomycin-induced skin fibrosis as measured by Masson’s staining of collagen and reduced Acta2 and Ctgf mRNA expression, whereas transduction of dermal fibroblasts with a lentiviral GSE4 expression vector reduced COL1A1, ACTA2 and CTGF gene expression after stimulation with bleomycin or TGF-β, in parallel to a reduction of the phospho-histone H2A.X marker of DNA damage. [Conclusions]: SSc is associated with TS, particularly in patients with lung disease or anti-topoisomerase I antibodies. Administration of GSE4 peptide attenuated experimental skin fibrosis and reduced fibroblast expression of profibrotic factors, supporting a role for oxidative DNA damage in scleroderma.The authors received financial support from Fondo de Investigación Sanitaria, Instituto de Salud Carlos III (PI19/01129, PI20/00335, and RIER network RD16/0012 RETICS program), co-financed by the European Regional Development Fund (FEDER)

    Improving zebrafish embryo xenotransplantation conditions by increasing incubation temperature and establishing a proliferation index with ZFtool

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    Background Zebrafish (Danio rerio) is a model organism that has emerged as a tool for cancer research, cancer being the second most common cause of death after cardiovascular disease for humans in the developed world. Zebrafish is a useful model for xenotransplantation of human cancer cells and toxicity studies of different chemotherapeutic compounds in vivo. Compared to the murine model, the zebrafish model is faster, can be screened using high-throughput methods and has a lower maintenance cost, making it possible and affordable to create personalized therapies. While several methods for cell proliferation determination based on image acquisition and quantification have been developed, some drawbacks still remain. In the xenotransplantation technique, quantification of cellular proliferation in vivo is critical to standardize the process for future preclinical applications of the model. Methods This study improved the conditions of the xenotransplantation technique – quantification of cellular proliferation in vivo was performed through image processing with our ZFtool software and optimization of temperature in order to standardize the process for a future preclinical applications. ZFtool was developed to establish a base threshold that eliminates embryo auto-fluorescence and measures the area of marked cells (GFP) and the intensity of those cells to define a ‘proliferation index’. Results The analysis of tumor cell proliferation at different temperatures (34 °C and 36 °C) in comparison to in vitro cell proliferation provides of a better proliferation rate, achieved as expected at 36°, a maintenance temperature not demonstrated up to now. The mortality of the embryos remained between 5% and 15%. 5- Fluorouracil was tested for 2 days, dissolved in the incubation medium, in order to quantify the reduction of the tumor mass injected. In almost all of the embryos incubated at 36 °C and incubated with 5-Fluorouracil, there was a significant tumor cell reduction compared with the control group. This was not the case at 34 °C. Conclusions Our results demonstrate that the proliferation of the injected cells is better at 36 °C and that this temperature is the most suitable for testing chemotherapeutic drugs like the 5-FluorouracilThis research was funded by the Fondo de Investigación Sanitaria (Instituto Carlos III) - FIS project (PI13/01388). The funding body had no role in the design of the study and collection, analysis, and interpretation of data and in writing of this manuscriptS

    Searching for non-Gaussianity in the VSA data

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    We have tested Very Small Array (VSA) observations of three regions of sky for the presence of non-Gaussianity, using high-order cumulants, Minkowski functionals, a wavelet-based test and a Bayesian joint power spectrum/non-Gaussianity analysis. We find the data from two regions to be consistent with Gaussianity. In the third region, we obtain a 96.7% detection of non-Gaussianity using the wavelet test. We perform simulations to characterise the tests, and conclude that this is consistent with expected residual point source contamination. There is therefore no evidence that this detection is of cosmological origin. Our simulations show that the tests would be sensitive to any residual point sources above the data's source subtraction level of 20 mJy. The tests are also sensitive to cosmic string networks at an rms fluctuation level of 105μK105 \mu K (i.e. equivalent to the best-fit observed value). They are not sensitive to string-induced fluctuations if an equal rms of Gaussian CDM fluctuations is added, thereby reducing the fluctuations due to the strings network to 74μK74 \mu K rms . We especially highlight the usefulness of non-Gaussianity testing in eliminating systematic effects from our data.Comment: Minor corrections; accepted for publication to MNRA
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