Empirical studies of cloud effects on UV radiation: A review

The interest in solar ultraviolet (UV) radiation from the scientific community and the general population has risen significantly in recent years because of the link between increased UV levels at the Earth's surface and depletion of ozone in the stratosphere. As a consequence of recent research, UV radiation climatologies have been developed, and effects of some atmospheric constituents (such as ozone or aerosols) have been studied broadly. Correspondingly, there are well-established relationships between, for example, total ozone column and UV radiation levels at the Earth's surface. Effects of clouds, however, are not so well described, given the intrinsic difficulties in properly describing cloud characteristics. Nevertheless, the effect of clouds cannot be neglected, and the variability that clouds induce on UV radiation is particularly significant when short timescales are involved. In this review we show, summarize, and compare several works that deal with the effect of clouds on UV radiation. Specifically, works reviewed here approach the issue from the empirical point of view: Some relationship between measured UV radiation in cloudy conditions and cloud-related information is given in each work. Basically, there are two groups of methods: techniques that are based on observations of cloudiness (either from human observers or by using devices such as sky cameras) and techniques that use measurements of broadband solar radiation as a surrogate for cloud observations. Some techniques combine both types of information. Comparison of results from different works is addressed through using the cloud modification factor (CMF) defined as the ratio between measured UV radiation in a cloudy sky and calculated radiation for a cloudless sky. Typical CMF values for overcast skies range from 0.3 to 0.7, depending both on cloud type and characteristics. Despite this large dispersion of values corresponding to the same cloud cover, it is clear that the cloud effect on UV radiation is 15–45% lower than the cloud effect on total solar radiation. The cloud effect is usually a reducing effect, but a significant number of works report an enhancement effect (that is increased UV radiation levels at the surface) due to the presence of clouds. The review concludes with some recommendations for future studies aimed to further analyze the cloud effects on UV radiation

Cystamine and cysteamine increase brain levels of BDNF in Huntington disease via HSJ1b and transglutaminase

There is no treatment for the neurodegenerative disorder Huntington disease (HD). Cystamine is a candidate drug; however, the mechanisms by which it operates remain unclear. We show here that cystamine increases levels of the heat shock DnaJ-containing protein 1b (HSJ1b) that are low in HD patients. HSJ1b inhibits polyQ-huntingtin¿induced death of striatal neurons and neuronal dysfunction in Caenorhabditis elegans. This neuroprotective effect involves stimulation of the secretory pathway through formation of clathrin-coated vesicles containing brain-derived neurotrophic factor (BDNF). Cystamine increases BDNF secretion from the Golgi region that is blocked by reducing HSJ1b levels or by overexpressing transglutaminase. We demonstrate that cysteamine, the FDA-approved reduced form of cystamine, is neuroprotective in HD mice by increasing BDNF levels in brain. Finally, cysteamine increases serum levels of BDNF in mouse and primate models of HD. Therefore, cysteamine is a potential treatment for HD, and serum BDNF levels can be used as a biomarker for drug efficacy.

Cat on a hot tin roof de Tennessee Williams o les aptituds dramàtiques de la deessa Diana

L'objectiu d'aquest article és mostrar quins són els rèdits dramàtics de la inclusió de la referència a la deessa Diana a Cat on a Hot Tin Roof de Tennessee Williams. En opinió del autor, no es tracta simplement d'una referència significativa, sinó que l'anàlisi acurada del text de Williams demostra que és un element vertaderament nuclear i cohesionador de tot el drama.

Matemáticos ingenieros e ingenieros matemáticos

No pretendo presentar un erudito trabajo histórico sobre el tema. sino que. a través de un sucinto paseo por la historia. en el que incluiré alguna anécdota para hacer más llevadera la exposición. intentaré explicar mis propias ideas sobre la Matemática Aplicada y sobre cuál debería ser su papel en una sociedad tan compleja como la que actualmente tenemos. En el fondo. incluso el título que he elegido es una coartada . Va a servirme exclusivamente de camino para llevarme a las conclusiones adecuadas. Espero que las ideas que expondré no sean consideradas innecesariamente provocativas. No es esa mi intención. Por el contrario. deseo hablar de lo que pienso sobre algunos temas. del porqué lo pienso y de cómo lo pienso. Y opino. con palabras del gran matemático español Puig Adam. que "conviene ser prudentes. no sea que por convencer a los ofendidos. ofendamos a los convencidos". No se si lo conseguiré. pero al menos no habré dejado de intentarlo

Associacionisme juvenil a l'Alt Empordà: 20 anys de joves compromesos

L’associacionisme juvenil es manifesta com un dels contextos socials per excel•lència, on el jove pot assolir un rol social, amb capacitat crítica i protagonisme en la presa de decisions. Uns espais que són necessaris per anar configurant la experiència cívica dels joves i que atresoren un potencial molt gran per a la democratització i la construcció de societats més fortes i cohesionades. Analitzar l'evolució de l'associacionisme juvenil al llarg dels darrers 20 anys i el perfil dels joves que hi han pres part durant aquest període, juntament amb el de conèixer el valor i el conjunt d’aportacions que aquest genera pels associats, i de quina forma incideixen aquestes en el seu itinerari personal i professional, configuren els interessos del present treball, contextualitzat a l’Alt Empordà i basat en bona mesura, en l’experiència vital de joves compromesos en el moviment associatiu de la comarca

Combined intermittent hypoxia and surface muscle electrostimulation as a method to increase peripheral blood progenitor cell concentration.

Background: Our goal was to determine whether short-term intermittent hypoxia exposure, at a level well tolerated by healthy humans and previously shown by our group to increase EPO and erythropoiesis, could mobilizehematopoietic stem cells (HSC) and increase their presence in peripheral circulation. Methods: Four healthy male subjects were subjected to three different protocols: one with only a hypoxic stimulus (OH), another with a hypoxic stimulus plus muscle electrostimulation (HME) and the third with only muscle electrostimulation (OME). Intermittent hypobaric hypoxia exposureconsisted of only three sessions of three hours at barometric pressure 540 hPa (equivalent to an altitude of 5000 m) for three consecutive days, whereas muscular electrostimulation was performed in two separate periods of 25 min in each session. Blood samples were obtained from an antecubital vein on three consecutive days immediately before the experiment and 24 h, 48 h, 4 days and 7 days after the last day of hypoxic exposure. Results: There was a clear increase in the number of circulating CD34+ cells after combined hypobaric hypoxia and muscular electrostimulation. This response was not observed after the isolated application of the same stimuli. Conclusion: Our results open a new application field for hypobaric systems as a way to increase efficiency in peripheral HSC collection.

Combined intermittent hypoxia and surface muscle electrostimulation as a method to increase peripheral blood progenitor cell concentration.

Background: Our goal was to determine whether short-term intermittent hypoxia exposure, at a level well tolerated by healthy humans and previously shown by our group to increase EPO and erythropoiesis, could mobilizehematopoietic stem cells (HSC) and increase their presence in peripheral circulation. Methods: Four healthy male subjects were subjected to three different protocols: one with only a hypoxic stimulus (OH), another with a hypoxic stimulus plus muscle electrostimulation (HME) and the third with only muscle electrostimulation (OME). Intermittent hypobaric hypoxia exposureconsisted of only three sessions of three hours at barometric pressure 540 hPa (equivalent to an altitude of 5000 m) for three consecutive days, whereas muscular electrostimulation was performed in two separate periods of 25 min in each session. Blood samples were obtained from an antecubital vein on three consecutive days immediately before the experiment and 24 h, 48 h, 4 days and 7 days after the last day of hypoxic exposure. Results: There was a clear increase in the number of circulating CD34+ cells after combined hypobaric hypoxia and muscular electrostimulation. This response was not observed after the isolated application of the same stimuli. Conclusion: Our results open a new application field for hypobaric systems as a way to increase efficiency in peripheral HSC collection.

Retrieving Cloud Characteristics from Ground-Based Daytime Color All-Sky Images

A discussion is presented of daytime sky imaging and techniques that may be applied to the analysis of full-color sky images to infer cloud macrophysical properties. Descriptions of two different types of skyimaging systems developed by the authors are presented, one of which has been developed into a commercially available instrument. Retrievals of fractional sky cover from automated processing methods are compared to human retrievals, both from direct observations and visual analyses of sky images. Although some uncertainty exists in fractional sky cover retrievals from sky images, this uncertainty is no greater than that attached to human observations for the commercially available sky-imager retrievals. Thus, the application of automatic digital image processing techniques on sky images is a useful method to complement, or even replace, traditional human observations of sky cover and, potentially, cloud type. Additionally, the possibilities for inferring other cloud parameters such as cloud brokenness and solar obstruction further enhance the usefulness of sky imagers

Turisme accessible: viabilitat de la creació d'un producte d'enoturisme accessible a l'Alt Empordà

Formem part d’una societat canviant, on tot està en constat moviment. El turisme, ja no és només una font d’ingressos, sinó que és un corrent de nous costums, noves idees i noves formes de vida. Estem dins d’un territori on una de les claus és l’adaptació a la societat, aproximar al màxim possible l’oferta existent cap a la nova demanda, als nous mercats. L’activitat turística experimenta canvis, apareixen nous turistes i, per tant, es percep l’obligació de crear nous productes per satisfer noves necessitats. El projecte que es presenta, segueix aquesta idea. Prèviament s’ha investigat sobre segments de mercat poc treballats i s’ha estudiat la possibilitat d’adaptar l’oferta existent d’un territori concret per aquest nínxol. L’idea és definir amb màxima precisió el nínxol de mercat pel que es vol treballar, així com també tenir especial exactitud sobre el què oferir

Turisme accessible: viabilitat de la creació d'un producte d'enoturisme accessible a l'Alt Empordà

Formem part d’una societat canviant, on tot està en constat moviment. El turisme, ja no és només una font d’ingressos, sinó que és un corrent de nous costums, noves idees i noves formes de vida. Estem dins d’un territori on una de les claus és l’adaptació a la societat, aproximar al màxim possible l’oferta existent cap a la nova demanda, als nous mercats. L’activitat turística experimenta canvis, apareixen nous turistes i, per tant, es percep l’obligació de crear nous productes per satisfer noves necessitats. El projecte que es presenta, segueix aquesta idea. Prèviament s’ha investigat sobre segments de mercat poc treballats i s’ha estudiat la possibilitat d’adaptar l’oferta existent d’un territori concret per aquest nínxol. L’idea és definir amb màxima precisió el nínxol de mercat pel que es vol treballar, així com també tenir especial exactitud sobre el què oferir

La construcción de la identidad docente del profesorado de educación infantil y primaria en la formación inicial y los primeros años de trabajo (Identidoc). Síntesis y principales resultados y contribuciones

Los docentes de los distintos ciclos del sistema educativo que están comenzando su vida profesional,si permanecen en esta actividad, trabajarán durante los próximos treinta o cuarentaaños con personas que vivirán parte de su vida en el siglo XXII. Este hecho constituye un puntode reflexión para los educadores quienes recibimos nuestra formación básica en el sigloXX, estamos desarrollando nuestro trabajo en el XXI, y tenemos la responsabilidad de preparara individuos para que puedan construir un mañana que ya es hoy (Millán y Sancho, 1995).Aquí comienza el interés de nuestros grupos de investigación por explorar cómo los hombresy las mujeres que han salido en los últimos años de las facultades de formación del profesorado,con las especialidades de educación infantil y primaria, aprenden a ser docentes. Cómose han ido constituyendo y posicionando como maestros y maestras durante la formación inicial y los primeros años de su vida profesional...

La construcción de la identidad docente del profesorado de educación infantil y primaria en la formación inicial y los primeros años de trabajo (Identidoc). Síntesis y principales resultados y contribuciones

Los docentes de los distintos ciclos del sistema educativo que están comenzando su vida profesional,si permanecen en esta actividad, trabajarán durante los próximos treinta o cuarentaaños con personas que vivirán parte de su vida en el siglo XXII. Este hecho constituye un puntode reflexión para los educadores quienes recibimos nuestra formación básica en el sigloXX, estamos desarrollando nuestro trabajo en el XXI, y tenemos la responsabilidad de preparara individuos para que puedan construir un mañana que ya es hoy (Millán y Sancho, 1995).Aquí comienza el interés de nuestros grupos de investigación por explorar cómo los hombresy las mujeres que han salido en los últimos años de las facultades de formación del profesorado,con las especialidades de educación infantil y primaria, aprenden a ser docentes. Cómose han ido constituyendo y posicionando como maestros y maestras durante la formación inicial y los primeros años de su vida profesional...