3,234 research outputs found
Managing the national road network maintenance in Spain
The Spanish Ministry of Public Works manages the National Road Network, which consists in 27,000 km. In 1992, the average age of pavements was 7.2 years, whereas at present it has increased to 9 years. The great heterogeneity of pavements, the constant increase in the network length and its gradual aging demand important budgets but also agile technical, economic and administrative management models. The Subdirectorate of Maintenance and Operation is responsible of management systems for this network, now helped by the engineering consultancy GETINSA. This communication shows the actual state of the pavement management that consists in an Integrated Database System comprising many parameters both about technical values and administrative follow-up of actions. It is connected to various pavement evolution models that allow managers to predict the future state of the roads, then to establish a maintenance policy. Finally, the Management System calculates a maintenance plan, detailing actions to be done in each section in a multi-year scenario, so that the investment and the road quality are optimised. The Management System software combines analytical formula with geographical information, used for representing results as well as part of the forecast and optimisation models, using the modern technology of “dynamic segments”. Attention has been paid to conciliate the operational organisation of maintenance works with the fact that optimal needs are detailed for each road section in too short distances to be executed separately. The communication starts analysing other existing Pavement Management Systems, then describes the Spanish situation and justifies which Pavement Management System is needed. The body of the text covers the description of the functionalities and design assumptions of the new System. Finally, the conclusions present some future evolutions for the Spanish Management Systems and the possibility to generalise its use to other road networks, either for pavement or other assets.
The Effect of Haptic Feedback on Basic Social. Interaction within Shared Virtual Environments
This paper describes an experiment that studies the effect of basic haptic feedback in creating a sense of social interaction within a shared virtual environment (SVE). Although there have been a number of studies investigating the effect of haptic feedback on collaborative task performance, they do not address the effect it has in inducing social presence. The purpose of this experiment is to show that haptic feedback enhances the sense of social presence within a mediated environment. An experiment was carried out using a shared desktop based virtual environment where 20 remotely located couples who did not know one another had to solve a puzzle together. In 10 groups they had shared haptic communication through their hands, and in another group they did not. Hence the haptic feedback was not used for completing the task itself, but rather as a means of social interacting – communicating with the other participant. The results suggest that basic haptic feedback increases the sense of social presence within the shared VE
Increasing significance of external quality assurance in higher education: current strategies applied by European agencies
[EN] Quality assurance of higher education programmes and institutions has been one of the cornerstones of the Bologna process since its creation. However, after more than one decade of implementation of the European quality assurance framework, many national systems are suffering from the so-called “evaluation fatigue”. From a thorough revision of key sectorial sources, this paper identifies a number of strategies currently being tested by European quality assurance agencies aimed at increasing significance and reducing bureaucracy of external quality assurance processes. http://ocs.editorial.upv.es/index.php/HEAD/HEAD18Sánchez Chaparro, T.; Gomez Frías, V. (2018). Increasing significance of external quality assurance in higher education: current strategies applied by European agencies. Editorial Universitat Politècnica de València. 1413-1420. https://doi.org/10.4995/HEAD18.2018.8215OCS1413142
The functional neuroanatomy of emotion regulation in major depressive disorder
A mood-congruent processing bias toward negative emotional information is a hallmark characteristic of the pathophysiology of major depressive disorder (MDD). Previous neuropsychological studies have provided evidence of this phenomenon in memory and attention paradigms. In addition, functional neuroimaging studies consistently report increased neural responses to negative emotional stimuli, including words and faces.
The amygdala plays an essential role in the determining the salience of a stimulus and is particularly tuned to the evaluation of facial expressions. Two pathways to the amygdala have been proposed: one involving higher-order cortical regions that permits explicit stimulus perception and one involving subcortical structures that allows rapid detection of non-conscious or implicit stimuli of emotional significance.
Several studies have explored the nature of explicit emotional face processing in MDD. However, few have focused on how the brain responds to non-conscious or implicit emotional information. Altered processing of emotional information, below the level of explicit conscious awareness, may contribute to the establishment and maintenance of illness-associated symptoms involving dysfunctional conscious perceptions and social interactions. Providing further evidence, recent research suggests that the mechanisms underlying antidepressant treatment may involve a reversal of the negative emotional processing bias associated with MDD.
The purpose of this thesis was to investigate the functional anatomical neural network of structures involved in mood-congruent processing biases toward non- conscious emotional information in MDD and to evaluate differences in this network associated with antidepressant treatment.
In Study I, a novel backward masking task was developed to examine differences in the hemodynamic response of the amygdala to sad (SN), happy (HN) and neutral (NN) faces presented below the level of explicit conscious awareness using functional magnetic resonance imaging (fMRI). Participants included individuals with current major depressive disorder (dMDD), MDD in full remission (rMDD) and healthy controls (HC). A subset of dMDD participants completed the fMRI task before and after eight weeks of antidepressant treatment with sertraline hydrochloride. An amygdala region-of-interest analysis revealed a greater hemodynamic response in the amygdala to masked-sad vs. masked-happy faces (SN-HN) in dMDD vs. HC. In contrast, HC participants showed a greater response to masked-happy faces. rMDD participants also showed a negative processing bias toward masked-sad faces similar to the dMDD group. In dMDD, the negative processing bias reversed and a positive processing bias emerged following antidepressant treatment.
In Studies II and III, a regional analysis of the cortical and subcortical networks involved with the amygdala in processing emotional information was used to evaluate differences between the dMDD and HC participants and dMDD participants before and after antidepressant treatment from Study I. In Study II, dMDD participants showed a
greater hemodynamic response to SN-HN in the hippocampus and anterior inferotemporal cortex. As well, participants showed a greater response to SN-NN or HN-NN in areas of the medial and orbital prefrontal cortex and superior temporal gyrus. In Study III, dMDD participants showed a greater response to SN-HN in the pre- vs. post-treatment condition in the pregenual anterior cingulate cortex, superior temporal gyrus and anterior inferotemporal gyrus. Additional regions of the sensory and visceromotor networks also showed an increased hemodynamic response to SN- NN before versus after treatment. The regions associated with these differential responses are known to participate with the amygdala in evaluating and responding to the salience of emotional stimuli.
Taken together, these studies provide insight into the underlying neurocircuitry associated with the processing of non-conscious emotional information. Furthermore, they reveal networks that are influenced by antidepressant treatment to alter brain function and establish a reversal of the negative processing bias and development of a normative positive processing bias in major depressive disorder
Phase-sensitive evidence for dx2-y2-pairing symmetry in the parent-structure high-Tc cuprate superconductor Sr1-xLaxCuO2
Even after 25 years of research the pairing mechanism and - at least for
electron doped compounds - also the order parameter symmetry of the high
transition temperature (high-Tc) cuprate superconductors is still under debate.
One of the reasons is the complex crystal structure of most of these materials.
An exception are the infinite layer (IL) compounds consisting essentially of
CuO2 planes. Unfortunately, these materials are difficult to grow and, thus,
there are only few experimental investigations. Recently, we succeeded in
depositing high quality films of the electron doped IL compound Sr1-xLaxCuO2
(SLCO), with x approximately 0.15, and on the fabrication of well-defined grain
boundary Josephson junctions (GBJs) based on such SLCO films. Here we report on
a phase sensitive study of the superconducting order parameter based on GBJ
SQUIDs from a SLCO film grown on a tetracrystal substrate. Our results show
that also the parent structure of the high-Tc cuprates has dx2-y2-wave
symmetry, which thus seems to be inherent to cuprate superconductivity.Comment: Submitted to PRL, 5 pages, 3 figures, supplementary information
included (4 pages, 4 figures
Hybrid thermoresponsive nanoparticles containing drug nanocrystals for NIR-triggered remote release
The on-demand administration of anaesthetic drugs can be a promising alternative for chronic pain management. To further improve the efficacy of drug delivery vectors, high drug loadings combined with a spatiotemporal control on the release can not only relief the pain according to patient''s needs, but also improve the drawbacks of conventional burst release delivery systems. In this study, a hybrid nanomaterial was developed by loading bupivacaine nanocrystals (BNCs) into oligo(ethylene glycol) methyl ether methacrylate (OEGMA)-based thermoresponsive nanogels and coupling them to NIR-absorbing biodegradable copper sulphide nanoparticles (CuS NPs). Those CuS NPs were surface modified with polyelectrolytes using layer-by-layer techniques to be efficiently attached to the surface of nanogels by means of supramolecular interactions. The encapsulation of bupivacaine in the form of nanocrystals allowed to achieve CuS@BNC-nanogels having drug loadings as high as 65.5 wt%. The nanocrystals acted as longlasting drug reservoirs, leading to an elevated localized drug content, which was useful for their application in prolonged pain relief. The CuS@BNC-nanogels exhibited favorable photothermal transducing properties upon NIR-light irradiation. The photothermal effect granted by the CuS NPs triggered the nano-crystallized drug release to be boosted by the collapse of the thermoresponsive nanogels upon heating. Remote control was achieved for on-demand release at a specific time and place, indicating their potential use as an externally activated triggerable drug-delivery system. Furthermore, cell viability tests and flow cytometry analysis were performed showing satisfactory cytocompatibility in the dose-ranging study having a subcytotoxic concentration of 0.05 mg/mL for CuS@BNC-nanogels. This remotely activated nanoplatform is a promising strategy for long-lasting controlled analgesia and a potential alternative for clinical pain management. (c) 2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND licens
Stability of a commercial lipase from Mucor javanicus: kinetic modeling of pH and temperature dependencies
The present communication reports experimental and modelling work pertaining to the independent roles of pH and temperature on deactivation of a crude lipase from Mucor javanicus. Experimental data oflipolytic activities were generated by a classic pH-stat assay on a
triolein emulsion following incubation at several pH values for a fixed time, or at several temperatures for various times; postulated models were then fitted by nonlinear fitting to such data. The pH-dependence data were best fit by assumption of three forms of enzyme with
increasing states of protonation, with pKa values of 6.2 and 11.3, respectively, where only the intermediate form is stable within the time frame considered. The thermal-dependence data were best fit by assumption of parallel steps of deactivation and rearrangement, with activation
energies of 228.8 and 221.7 kJ mol~l, respectively
Supercapacitor in battery charges of photovoltaic panel: analysis of the technical feasibility
The power generation from photovoltaic sources is variable and may contain unhoped fluctuations, which can be relieved by using energy storage systems. However, there is a technical contradiction in extracting the maximum power from a photovoltaic panel and the charge cycle of a battery. To overcome this problem, this paper presents an improvement consisting in a collaborative association of lithium ion batteries and supercapacitors showing the technical feasibility in a photovoltaic system.
The structure of the energy conversion system was developed and was set up the converter’s configuration, design and operation simulation. The power management of full system implementation was simulated and the results are presented. The proposed system development and it technical analysis was carried out for both situations, with and without the use of supercapacitor. It was concluded that the supercapacitor in the photovoltaic systems bring better charging conditions, resulting in shorter charging times and better system performances.info:eu-repo/semantics/publishedVersio
External ontogenetic changes of larval structures in Elachistocleis bicolor (Anura: Microhylidae: Gastrophryninae)
Although the external larval morphology of many species of Microhylidae has been characterized, ontogenetic studies in the family are scarce and partial. In the present study, we describe the development of the oral funnel, external gills, external nares, operculum, spiracle, and adhesive organs of Elachistocleis bicolor with the aim to contribute to future ontogenetic, evolutionary, and phylogenetic studies. The development of E. bicolor is similar to that of other species with free-swimming tadpoles as Microhyla ornata, Dermatonotus muelleri and Uperodon globulosus. The ontogeny of the oral apparatus shows only the early stages of the pattern most common in anurans. After the invagination of the stomodeum, the anterior and posterior labia are defined, but the keratinized structures are not formed. The conical adhesive glands are similar to those of Physalaemus and Dendropsophus tadpoles, but in E. bicolor, these develop in contact with the posterior labium. The external nares remain closed during most of the larval phase. During ontogeny, the external gills are simultaneously covered by a transverse operculum fold, which later advances towards the posteromedial ventral region, forming the spiracle, while in Type IV larvae the operculum folds close from right to left, covering the right gill first. The distinct larval characters of Microhylidae appear between the last embryonic stages and the first larval stages. Therefore, the consideration of these stages can be of great value in future studies of anuran development in phylogenetic and evolutionary contexts. Ontogenetic studies in microhylid tadpoles are fundamental to identify heterochronic processes, to interpret the variability of larval structures, and to establish or reinforce hypotheses about the origin of larval structures.Fil: Abreliano, Fernanda Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Departamento de Biología. Laboratorio de Herpetología; ArgentinaFil: Zaracho, Victor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Departamento de Biología. Laboratorio de Herpetología; ArgentinaFil: Sandoval, María Teresa. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Departamento de Biología. Laboratorio de Herpetología; Argentin
Medios, técnicas e instrumentos de evaluación formativa y compartida del aprendizaje en educación superior
En este trabajo presentamos una revisión de la literatura en español sobre la evaluación formativa y compartida del aprendizaje en el nivel universitario referente a los medios, técnicas e instrumentos de dicha evaluación. Los principales resultados apuntan a que a existe una cierta confusión en la utilización de términos como “instrumentos”, “herramientas”, “técnicas”, “dispositivos”, etc. (en ocasiones se utilizan diferentes términos para referirse a un mismo concepto, o bien, el mismo término para referirse a conceptos y prácticas diferentes; se enumeran entremezclados, confundiendo unos con otros); y que no se sigue una clasificación claramente delimitada. Finalmente, se presenta una propuesta de marco conceptual para hacer referencia a los “medios”, “técnicas” e “instrumentos” de evaluación formativa y compartida en educación superior, definiendo de manera precisa la terminología asociada.In this article we present a review of the literature in Spanish on formative and shared assessment of learning at the university level in relation to the means, techniques, and instruments of such assessment. The main results suggest that there is some confusion in the use of terms such as “instruments,” “tools,” “techniques,” “devices,” etc. (at times different terms are used to refer to the same concept or the same term to refer to different concepts and practices; terms are used interchangeably, creating confusion among them), without following a clearly defined classification. Finally, we present a proposed conceptual framework for referring to the “means,” “techniques,” and “instruments” of formative and shared assessment in higher education, precisely defining the associated terminology
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