University of Valencia
Repositori d'Objectes Digitals per a l'Ensenyament la Recerca i la CulturaNot a member yet
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Perovskite solar cells: Towards the net zero scenario
No full textAt present, there is an urgent need to reduce greenhouse gas emissions to mitigate the climate change that threatens humanity and our planet's ecosystems. A way to achieve this is by increasing renewable energy production, where solar photovoltaic plays a key role. However, the current commercial crystalline silicon photovoltaic technology might not be enough to achieve the required targets. In this work, we describe the latest advances of an emerging photovoltaic technology known as perovskites. In just ten years of development perovskite solar cells have matched the performance of current commercial crystalline silicon. Here, we outline how to scale and improve the stability of perovskite solar cells as well as examples of applications such as their integration with silicon solar cells, semitransparent solar cells, and their use in outer space
Comportamiento sexual de un grupo de jovenes ,adultos ,estudiantes de la ciudad de Maputo, Mozambique
No full textLograr la práctica del sexo seguro, sobre todo entre la población joven, representa en la actualidad el principal objetivo de prevención en la transmisión sexual del VIH / SIDA en Mozambique. Un estudio fue realizado durante el mes de noviembre de 2002, con la finalidad de evaluar las actitudes sexuales en un grupo de estudiantes de Maputo, Mozambique. Se estudiaron las características sociodemográficas y actitudes relacionadas con el comportamiento sexual. La descripción de las características se realizó mediante las medias y la desviación estándar para las cuantitativas y frecuencias relativas e intervalos de confianza, para las cualitativas. 45 estudiantes de ambos sexos participaron en el estudio. La edad promedio total fue de 25,97±6,09 años, de 23,83±3,04 años para las mujeres y de 26,75±6,75 para los hombres. La experiencia sexual fue relatada por todos los encuestados, la edad promedio de inicio de ésta fue de 17,25±2,73 años para las mujeres, y de 15,64±2,71 para los hombres; en el 91,11% (79,93-97,11) ésta no fue planificada; lo cual lleva a que se pueda plantear que la conducta sexual presenta aspectos que exponen al grupo estudiado a los riesgos de infección por el VIH pese a observarse un notable incremento en el uso del preservativo relatado para todas relaciones sexuales comparado con la primera experiencia sexual, practica que no ha acompañada por otras que refuercen su protección frente al VIH. Palabras claves: Mozambique. Jóvenes. Comportamiento sexual. Prevención. Riesgo
Antibodies against Lewis antigens inhibit the binding of human norovirus GII.4 virus-like particles to saliva but not to intestinal Caco-2 cells.
No full textBackground Human noroviruses (NoVs) are the main cause of gastroenteritis worldwide. The most commonly detected NoV strains belong to the genetically diverse GII.4 genotype, with new pandemic variants emerging periodically. Despite extensive efforts, NoV investigation has been hampered by the lack of an effective in vitro cell culture system. However, NoV-derived recombinant virus-like particles (VLPs) resembling empty capsids are good surrogates for analysing NoV antigenicity and virus-ligand interactions. NoV VLPs have been reported to bind to histo-blood group antigens (HBGAs). We have analysed the ability of NoV VLPs derived from GI.1 genotype and from three GII.4 genotype variants, GII.4-1999, GII.4-2004 and GII.4-2006b, to bind to porcine gastric mucin (PGM), human saliva and differentiated human intestinal Caco-2 cells (D-Caco-2 cells). Results Distinct patterns of saliva binding with the NoV GII.4 variant VLPs were observed, although they bound to D-Caco-2 cells independently of the expression of HBGAs. Monoclonal antibodies against Lewis antigens were able to block the binding of NoV VLPs to saliva, but not to D-Caco-2 cells. Blocking HBGAs on the surface of D-Caco-2 cells with specific monoclonal antibodies did not affect NoV VLP binding to cellular membranes. Co-localisation of Lewis y (Ley) and H-type 2 antigens with NoV VLPs was not observed by immunofluorescence assays. Conclusion Although the binding of NoV VLPs of GII.4 genotype variants to human saliva samples occur with distinct HBGA binding patterns and can be blocked by antibodies against Lewis antigens, their attachment to D-Caco-2 cells can be mediated by other receptors, which still need further investigatio
Rational Design of Chitin Deacetylase Inhibitors for Sustainable Agricultural Use Based on Molecular Topology
No full textFungicide resistance is a major concern in modern agriculture; therefore, there is a pressing demand to develop new, greener chemicals. Chitin is a major component of the fungal cell wall and a well-known elicitor of plant immunity. To overcome chitin recognition, fungal pathogens developed different strategies, with chitin deacetylase (CDA) activity being the most conserved. This enzyme is responsible for hydrolyzing the N-acetamido group in N-acetylglucosamine units of chitin to convert it to chitosan, a compound that can no longer be recognized by the plant. In previous works, we observed that treatments with CDA inhibitors, such as carboxylic acids, reduced the symptoms of cucurbit powdery mildew and induced rapid activation of chitin-triggered immunity, indicating that CDA could be an interesting target for fungicide development. In this work, we developed an in silico strategy based on QSAR (quantitative structure-activity relationship) and molecular topology (MT) to discover new, specific, and potent CAD inhibitors. Starting with the chemical structures of few carboxylic acids, with and without disease control activity, three predictive equations based on the MT paradigm were developed to identify a group of potential molecules. Their fungicidal activity was experimentally tested, and their specificity as CDA inhibitors was studied for the three best candidates by molecular docking simulations. To our knowledge, this is the first time that MT has been used for the identification of potential CDA inhibitors to be used against resistant powdery mildew strains. In this sense, we consider of special interest the discovery of molecules capable of stimulating the immune system of plants by triggering a defensive response against fungal species that are highly resistant to fungicides such as powdery mildew
The impact of a web-based lifestyle educational program ('Living Better') reintervention on hypertensive overweight or obese patients
No full text'Living Better', a self-administered web-based intervention, designed to facilitate lifestyle changes, has already shown positive short- and medium-term health benefits in patients with an obesity−hypertension phenotype. The objectives of this study were: (1) to examine the long-term (3-year) evolution of a group of hypertensive overweight or obese patients who had already followed the 'Living Better' program; (2) to analyze the effects of completing this program a second time (reintervention) during the COVID-19 pandemic. A quasi-experimental design was used. We recruited 29 individuals from the 105 who had participated in our first study. We assessed and compared their systolic and diastolic blood pressure (SBP and DBP), body mass index (BMI), eating behavior, and physical activity (PA) level (reported as METs-min/week), at Time 0 (first intervention follow-up), Time 1 (before the reintervention), and Time 2 (post-reintervention). Our results showed significant improvements between Time 1 and Time 2 in SBP (−4.7 (−8.7 to −0.7); p = 0.017), DBP (−3.5 (−6.2 to −0.8); p = 0.009), BMI (−0.7 (−1.0 to −0.4); p 0.24). Implementation of the 'Living Better' program maintained positive long-term (3-year) health benefits in patients with an obesity−hypertension phenotype. Moreover, a reintervention with this program during the COVID-19 pandemic produced significant improvements in blood pressure, BMI, eating behavior, and P
Validation of circulating histone detection by mass spectrometry for early diagnosis, prognosis, and management of critically ill septic patients
No full textBackground: As leading contributors to worldwide morbidity and mortality, sepsis and septic shock are considered a major global health concern. Proactive biomarker identification in patients with sepsis suspicion at any time remains a daunting challenge for hospitals. Despite great progress in the understanding of clinical and molecular aspects of sepsis, its definition, diagnosis, and treatment remain challenging, highlighting a need for new biomarkers with potential to improve critically ill patient management. In this study we validate a quantitative mass spectrometry method to measure circulating histone levels in plasma samples for the diagnosis and prognosis of sepsis and septic shock patients. Methods: We used the mass spectrometry technique of multiple reaction monitoring to quantify circulating histones H2B and H3 in plasma from a monocenter cohort of critically ill patients admitted to an Intensive Care Unit (ICU) and evaluated its performance for the diagnosis and prognosis of sepsis and septic shock (SS). Results: Our results highlight the potential of our test for early diagnosis of sepsis and SS. H2B levels above 121.40 ng/mL (IQR 446.70) were indicative of SS. The value of blood circulating histones to identify a subset of SS patients in a more severe stage with associated organ failure was also tested, revealing circulating levels of histones H2B above 435.61 ng/ml (IQR 2407.10) and H3 above 300.61 ng/ml (IQR 912.77) in septic shock patients with organ failure requiring invasive organ support therapies. Importantly, we found levels of H2B and H3 above 400.44 ng/mL (IQR 1335.54) and 258.25 (IQR 470.44), respectively in those patients who debut with disseminated intravascular coagulation (DIC). Finally, a receiver operating characteristic curve (ROC curve) demonstrated the prognostic value of circulating histone H3 to predict fatal outcomes and found for histone H3 an area under the curve (AUC) of 0.720 (CI 0.546-0.895) p < 0.016 on a positive test cut-off point at 486.84 ng/mL, showing a sensitivity of 66.7% and specificity of 73.9%. Conclusions: Circulating histones analyzed by MS can be used to diagnose SS and identify patients at high risk of suffering DIC and fatal outcome
Effect of Reliable Recovery on Health Care Costs and Productivity Losses in Emotional Disorders
No full textDespite the high economic costs associated with emotional disorders, relatively few studies have examined the variation in costs according to whether the patient has achieved a reliable recovery. The aim of this study was to explore differences in health care costs and productivity losses between primary care patients from a previous randomized controlled trial (RCT)¿PsicAP¿with emotional symp- toms who achieved a reliable recovery and those who did not after transdiagnostic cognitive-behavioral therapy (TD-CBT) plus treatment as usual (TAU) or TAU alone. Sociodemographic and cost data were obtained for 134 participants treated at five primary care centers in Madrid for the 12-month posttreatment period. Reliable recovery rates were higher in the patients who received TD-CBT + TAU versus TAU alone (66% vs. 34%, respectively; chi-square = 13.78, df = 1, p < .001). Patients who did not achieve reliable recovery incurred more costs, especially associated with general practitioner consultations (t = 3.01, df = 132, p = .003), use of emergency depart- ments (t = 2.20, df = 132, p = .030), total health care costs (t = 2.01, df = 132, p = .040), and sick leaves (t = 1.97, df = 132, p = .048). These findings underscore the societal importance of achieving a reliable recovery in patients with emotional disorders, and further support the value of add- ing TD-CBT to TAU in the primary care settin
Effectiveness of mindfulness-based interventions on psychotherapy processes: A systematic review
Get PDFIn the field of psychotherapy, scientific research has highlighted the importance of empathy and therapeutic alliance in regard to the effectiveness and better results of psychological treatments. In recent years, mindfulness-based interventions (MBIs) have shown to be effective at increasing empathy and therapeutic alliance and how this could affect the patients' symptomatology. In this study, we conducted a systematic review of the effectiveness of MBIs applied to psychotherapists to improve their empathy, the therapeutic alliance and the patients' symptomatology. Sixteen studies evaluating the impact of an MBI on some of these variables were identified, of which six included measures evaluated by the patients whose ahe MBI. The risk of bias of the included studies was analysed following the methodological standards. We found very different designs and methodologies in the studies included in this review, with few of them including a control group. The results show a limited increase in empathy, measured by the psychotherapist, after an MBI. However, the results in therapeutic alliance are not conclusive, as well as the improvements in the perception of patients about their symptomatology. It is concluded that MBIs can have a beneficial effect on the psychotherapeutic practice, through the development of psychotherapists' empathy. Future research would require new studies with a higher methodological quality, and in which the effects of MBIs on empathy, therapeutic alliance and patients' symptomatology and the relationships between them are analyze
El uso estratégico de la interacción en la comunicación delos políticos argentinos en Facebook.
No full textLos flujos comunicacionales que discurren en las redes sociales y la derivación en cámaras de eco han comenzado a ser objeto de investigación en los últimos años, en parte por sus consecuencias en la construcción de una esfera pública anclada en valores democráticos. Recientes estudios afirman que la interacción digital origina encuentros con voces que lejos de alentar el debate confirman opiniones preexistentes. Esta investigación estudia el papel que los dirigentes políticos argentinos cumplen en la construcción de cámaras de eco en Facebook a partir del uso estratégico que realizan de las herramientas de interacción que esta red ofrece. Para ello se analizaron los mensajes que Cristina Fernández, Mauricio Macri, Sergio Massa y Daniel Scioli publicaron durante el periodo noviembre de 2014-noviembre de 2015 en Facebook, la red social en la que más de la mitad de los argentinos tiene una cuenta de perfil activa. Los resultados de este estudio empírico demuestran que los dirigentes incorporan, pero escasamente, las herramientas de interacción propias de Facebook y que, además, el uso que realizan responde a una lógica difusionista antes que conversacional, enmarcada en una comunicación personalista que colabora en la construcción de espacios de interacción cerrados a puntos de vista divergentes
El diseño de una base de datos para una representación de las fuentes históricas valencianas
Get PDFEn el ámbito de las Humanidades Digitales, es crucial el desarrollo de bases de datos para el acceso y organización eficiente de su contenido, también sobre fuentes históricas. Tanto las «instituciones-memoria» como los proyectos universitarios se especializan desde hace décadas en la creación y mejora de estas, con distintos grados de complejidad, para facilitar la tarea de la comunidad científica y, en ocasiones, centralizar la información que se encuentra dispersa en la red. Esto sucede con el proyecto VaHiFo (Valentiae Historici Fontes), de la UV/IIFV, que, en un esfuerzo por reunir las referencias sobre fuentes históricas valencianas, se ha embarcado en su localización y registro, así como en la creación de un sistema de información que las organice y gestione. El objetivo de este artículo es mostrar el proceso de diseño de dicha herramienta, que atiende a aspectos como la sencillez de uso, perdurabilidad y capacidad evolutiva. Asimismo, se ofrece una metodología que conceptualiza la descripción unificada de las fuentes históricas valencianas, de distinto género y con diversas tipologías materiales o de edición, y que además resalta la relación entre los testimonios de su tradición.Palabras clave: humanidades digitales, base de datos, fuentes históricas valencianas, metodologí