346 research outputs found
Deslizamientos naturales y comunidades pionera de ecosistemas montanos al occidente del parque nacional podocarpus (ecuador)
El Parque Nacional Podocarpus (PNP), ubicado al sur del Ecuador, ocupa una posición climatológica clave con respecto a la deflexión de Huancabamba aledaña a esta área hacia el sur, que ocasiona una barrera natural de distribución de especies y por otro lado este aislamiento biogeográfíco ha originado especiación florística en algunas especies. La geografía accidentada de esta región, sumada a la escasa capa vegetal y precipitaciones que superan los 6000 mm en los páramos, ocasiona impactos severos en los flancos orientales y occidentales de la baja Cordillera Oriental que no sobrepasa los 3700 m, en sus límites altitudinales más altos. Es aquí donde existe una dinámica alta de deslizamientos, los mismos que si bien afectan la diversidad vegetal, también son considerados un motor generador de continuos procesos de regeneración. Se establecieron 138 parcelas, distribuidas a o largo de un gradiente latitudinal y altitudinal, de 1 x 5m al occidente del PNP, encontrándose 218 especies representantes de 180 géneros y 51 familias; el piso altitudinal de mayor diversidad está a los 2700 m. El análisis TWINSPAN separó nueve comunidades vegetales, mientras que el análisis multivariado CANOCO, determinó que las características edafológicas influyen en la composición de la vegetación, mientras que la altitud y la pendiente no establecen notable diferencia
Personal life pathways and professional identities. “engineers and graduates sweep over the middle level”
Fil: Lozano, Eduardo E. Universidad Nacional de Río Negro. Sede Alto Valle y Valle Medio; Argentina.Fil: Carranza, Pablo. Universidad Nacional de Río Negro. Sede Alto Valle y Valle Medio; Argentina.Fil: Ruiz, Maria E. Universidad Nacional de Río Negro. Sede Alto Valle y Valle Medio; Argentina.Este estudio de carácter preliminar, y desde el escenario inicial que brindan datos tratados estadísticamente, expresiones de los medios de comunicación y percepciones sociales que se manifiestan en la cotidianeidad de las instituciones educativas, se interesa por saber quiénes son y qué trayectorias han desarrollado sujetos concretos, profesionales, que no tienen título de profesores y dan clases de matemática, biología, física y química en el nivel medio de la provincia de Río Negro. Adoptamos una perspectiva que se apoya en el entrecruzamiento de la historia de los sujetos concretos, la historia de la dinámica y las características del trabajo docente en el nivel medio y también del contexto social general, ya que si se construyeran esos elementos se advertiría la complejidad de la realidad socioeducativa y se comprenderían cómo, a pesar de ciertas homogeneidades estructurales, pueden reconocerse recorridos diferentes y también diferentes significaciones otorgadas a las mismas oportunidades disponibles (Cragnolino, 2006). Se llevaron a cabo entrevistas en profundidad a profesionales, maestros y profesores que enseñan ciencias en el nivel medio, centrando la atención para este avance preliminar en seis profesionales que trabajan en el nivel medio de Río Negro
Pyrene-Appended Boronic Acids on Graphene Foam Electrodes Provide Quantum Capacitance-Based Molecular Sensors for Lactate
Molecular recognition and sensing can be coupled to interfacial capacitance changes on graphene foam surfaces linked to double layer effects and coupled to enhanced quantum capacitance. 3D graphene foam film electrodes (Gii-Sens; thickness approximately 40 μm; roughness factor approximately 100) immersed in aqueous buffer media exhibit an order of magnitude jump in electrochemical capacitance upon adsorption of a charged molecular receptor based on pyrene-appended boronic acids (here, 4-borono-1-(pyren-2-ylmethyl)pyridin-1-ium bromide, or abbreviated T1). This pyrene-appended pyridinium boronic acid receptor is employed here as a molecular receptor for lactate. In the presence of lactate and at pH 4.0 (after pH optimization), the electrochemical capacitance (determined by impedance spectroscopy) doubles again. Lactic acid binding is expressed with a Hillian binding constant (Klactate = 75 mol-1 dm3 and α = 0.8 in aqueous buffer, Klactate = 460 mol-1 dm3 and α = 0.8 in artificial sweat, and Klactate = 340 mol-1 dm3 and α = 0.65 in human serum). The result is a selective molecular probe response for lactic acid with LoD = 1.3, 1.4, and 1.8 mM in aqueous buffer media (pH 4.0), in artificial sweat (adjusted to pH 4.7), and in human serum (pH adjusted to 4.0), respectively. The role of the pyrene-appended boronic acid is discussed based on the double layer structure and quantum capacitance changes. In the future, this new type of molecular capacitance sensor could provide selective enzyme-free analysis without analyte consumption for a wider range of analytes and complex environments
Design of New Dispersants Using Machine Learning and Visual Analytics
Artificial intelligence (AI) is an emerging technology that is revolutionizing the discovery of new materials. One key application of AI is virtual screening of chemical libraries, which enables the accelerated discovery of materials with desired properties. In this study, we developed computational models to predict the dispersancy efficiency of oil and lubricant additives, a critical property in their design that can be estimated through a quantity named blotter spot. We propose a comprehensive approach that combines machine learning techniques with visual analytics strategies in an interactive tool that supports domain experts’ decision-making. We evaluated the proposed models quantitatively and illustrated their benefits through a case study. Specifically, we analyzed a series of virtual polyisobutylene succinimide (PIBSI) molecules derived from a known reference substrate. Our best-performing probabilistic model was Bayesian Additive Regression Trees (BART), which achieved a mean absolute error of (Formula presented.) and a root mean square error of (Formula presented.), as estimated through 5-fold cross-validation. To facilitate future research, we have made the dataset, including the potential dispersants used for modeling, publicly available. Our approach can help accelerate the discovery of new oil and lubricant additives, and our interactive tool can aid domain experts in making informed decisions based on blotter spot and other key propertie
In Vitro Evaluation of the Biological Effects of ACTIVA Kids BioACTIVE Restorative, Ionolux, and Riva Light Cure on Human Dental Pulp Stem Cells
This study aimed to analyze the biological effects of three new bioactive materials on cell survival, migration, morphology, and attachment in vitro. ACTIVA Kids BioACTIVE Restorative (Pulpdent, Watertown, MA, USA) (Activa), Ionolux (Voco, Cuxhaven, Germany), and Riva Light Cure UV (SDI, Bayswater, Australia) (Riva) were handled and conditioned with a serum-free culture medium. Stem cells from human dental pulp (hDPSCs) were exposed to material extracts, and metabolic activity, cell migration, and cell morphology were evaluated. Cell adhesion to the different materials was analyzed by scanning electron microscopy (SEM). The chemical composition of the materials was evaluated by energy-dispersive X-ray (EDX). One-way analysis of variance followed by a Tukey test was performed (p < 0.05). Ionolux promoted a drastic reduction in metabolic activity and wound closure compared to the control (p < 0.05), whereas Activa induced adequate metabolic activity and cell migration. Moreover, SEM and immunofluorescence analysis showed abundant cells exposed to Activa. The materials showed different surface morphologies, and EDX spectra exhibited different peaks of C, O, Si, S, Ca, and F ions in glass ionomer cements. The results showed that Activa induced cell migration, cell attachment, and cell viability to a greater extent than Riva and Ionolux.The Spanish Net of Cell Therapy (TerCel), RETICS subprograms of the I+D+I 2013-2016 Spanish National Plan, and project “RD16/0011/0001” funded by the Instituto de Salud Carlos III to JMM and co-funded by the European Regional Development Fund supported this workS
Neural plasticity of the uterus : New targets for endometrial cancer?
Altres ajuts: European Regional Development Fund (FEDER); FMMA grant (AP166942017); European Social Fund (ESF 'Investing in Your Future').Endometrial carcinoma is the most common gynecological malignancy in Western countries and is expected to increase in the following years because of the high index of obesity in the population. Recently, neural signaling has been recognized as part of the tumor microenvironment, playing an active role in tumor progression and invasion of different solid tumor types. The uterus stands out for the physiological plasticity of its peripheral nerves due to cyclic remodeling brought on by estrogen and progesterone hormones throughout the reproductive cycle. Therefore, a precise understanding of nerve-cancer crosstalk and the contribution of the organ-intrinsic neuroplasticity, mediated by estrogen and progesterone, of the uterine is urgently needed. The development of new and innovative medicines for patients with endometrial cancer would increase their quality of life and health. This review compiles information on the architecture and function of autonomous uterine neural innervations and the influence of hormone-dependent nerves in normal uterus and tumor progression. It also explores new therapeutic possibilities for endometrial cancer using these endocrine and neural advantages
Depression in internal medicine inpatients at the time of hospital discharge and referral to primary care
Background and objectives: This is the first multi-center study intended to document the prevalence, characteristics, and associations of depression in Medicine patients at the time of hospital discharge and their referral to Primary Care (PC). Methods: Adult patients randomly selected among consecutive admissions to Medicine wards in 8 hospitals in Spain, covering health districts, were examined in a two-phase ''case-finding'' procedure. Standardized, Spanish versions of instruments were used, including the Standardized Polyvalent Psychiatric Interview (SPPI) and Cumulative Illness Rating Scale (CIRS). Cases of depression were diagnosed according to ICD-10 general hospital research criteria. Results: Three hundred and twelve patients with treatable depression and 777 non-depressed controls were identified. In a conservative estimate, the global prevalence of major depression was 7.1%, dysthymia 4.2% and adjustment depression 7.1%, and 51.9% of cases were of moderate/ severe intensity. Depression was more frequent in women, the differences being significant in all categories of depression. The prevalence of depression was lower in individuals aged 85 or more years, the differences being significant in cases of both dysthymia and adjustment depression. A clear pattern of decreasing prevalence with age was observed in women. The depressed had as an average five medical systems affected, and higher CIRS scores compared with the controls, the differences being significant in cases of both major depression and dysthymia. Conclusions: This is the first report showing a considerable prevalence of treatable cases of depression in Medicine patients at the time of hospital discharge and referral to PC. Depression is associated with the severity of the medical condition, and differences observed by age and sex have clinical implications. Paper read at the 3rd Annual Meeting of the European Association of Psychosomatic Medicine, Nuremberg 2015. © 2022 Asociación Universitaria de Zaragoza para el Progreso de la Psiquiatría y la Salud Menta
Biodiversity Assessment and Geographical Affinities of Discards in Clam Fisheries in the Atlantic–Mediterranean Transition (Northern Alboran Sea)
This study focused on the assessment and quantification of discards generated by clam fisheries along the northern Alboran Sea (western Mediterranean). Discard samples (n = 278) were collected throughout one year on board nine commercial vessels. A total of 129 species were identified, mostly represented by molluscs (72 spp.), arthropods (20 spp.) and echinoderms (12 spp.). Molluscs dominated in terms of abundance (67.5%) and biomass (94.2%). The superfamily Paguroidea (i.e. hermit crabs), together with undersized target individuals, were the most abundant taxa. The abundance and biomass of discards displayed significant maximum values in winter, which could be partly related to biotic factors including population dynamics of some dominant species. Multivariate analyses indicated the presence of different assemblages related to the targeted bivalve species, reflecting the transition between a fine surface-sands biocoenosis exposed to wave action and a well-sorted fine sands biocoenosis below 5 m depth. Analysis of biogeographical affinities showed that most discarded species (73.2%) have an extensive Atlantic range, whereas 7.1% have a restricted distribution within the Mediterranean. The presence of subtropical species highlights the uniqueness of this area (the Atlantic–Mediterranean transition) in European seas. The usefulness of discard analysis for biodiversity assessment is discussed.Postprin
Deep-sea habitat characterization using acoustic data and underwater imagery in Gazul mud volcano (Gulf of Cádiz, NE Atlantic)
Gazul is the shallowest mud volcano (MV) within the Shallow Field of Fluid Expulsion (SFFE) of the northeastern Gulf of Cádiz (NE Atlantic; 300–1200 m depth). The SFFE represents an important geo- and biodiversity area that was designated as a Site of Community Importance under the European Habitats Directive in 2014. In this study, geological features, habitats and associated biodiversity, as well as anthropogenic impacts, were characterized at Gazul MV from underwater imagery and multibeam bathymetry. Multivariate methods using the Bray-Curtis similarity index identified six main habitats, each of which harbored a characteristic faunal assemblage that included: (1) sandy ripple bottoms typified by the actiniarian Actinauge richardi; (2) sandy, muddy, coarse sand and bioclastic bottoms dominated by the solitary coral Flabellum chunii; (3) coarse sand and bioclastic bottoms, together with soft sediments covered by scattered methane-derived authigenic carbonates (MDACs) (mixed bottoms), characterized by the echinoid Cidaris cidaris; (4) hard bottoms comprising MDACs dominated by a wide variety of sponges and gorgonians; (5) coral-rubble bottoms typified by the presence of colonial scleractinian communities dominated by Madrepora oculata; and (6) mixed bottoms characterized by the presence of a styelid ascidian. Slope and water depth were the main factors explaining assemblages’ distribution, which was also supported by the presence of MDACs such as slabs, crusts and chimneys on the seafloor, as well as by the geomorphologic diversity of Gazul MV. The results highlight Gazul MV as an eco-biologically important area harboring different vulnerable marine ecosystem (VME) elements with indicator taxa such as scleractinians, sponges, gorgonians and black corals. ROV images revealed abandoned or lost fishing gears and marine debris on the seafloor, indicating anthropogenic impacts in Gazul MV and adjacent areas. Indeed trawling fisheries activities have also been detected in Vessel Monitoring System datasets. A fishery restricted area is recommended in Gazul MV due to the occurrence of diverse VMEs and species included in different conservation directives and conventions.Postprin
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