495 research outputs found
Accretion and photodesorption of CO ice as a function of the incident angle of deposition
Non-thermal desorption of inter- and circum-stellar ice mantles on dust
grains, in particular ultraviolet photon-induced desorption, has gained
importance in recent years. These processes may account for the observed gas
phase abundances of molecules like CO toward cold interstellar clouds. Ice
mantle growth results from gas molecules impinging on the dust from all
directions and incidence angles. Nevertheless, the effect of the incident angle
for deposition on ice photo-desorption rate has not been studied. This work
explores the impact on the accretion and photodesorption rates of the incidence
angle of CO gas molecules with the cold surface during deposition of a CO ice
layer. Infrared spectroscopy monitored CO ice upon deposition at different
angles, ultraviolet-irradiation, and subsequent warm-up. Vacuum-ultraviolet
spectroscopy and a Ni-mesh measured the emission of the ultraviolet lamp.
Molecules ejected from the ice to the gas during irradiation or warm-up were
characterized by a quadrupole mass spectrometer. The photodesorption rate of CO
ice deposited at 11 K and different incident angles was rather stable between 0
and 45. A maximum in the CO photodesorption rate appeared around
70-incidence deposition angle. The same deposition angle leads to the
maximum surface area of water ice. Although this study of the surface area
could not be performed for CO ice, the similar angle dependence in the
photodesorption and the ice surface area suggests that they are closely
related. Further evidence for a dependence of CO ice morphology on deposition
angle is provided by thermal desorption of CO ice experiments
Lab-on-a-chip platforms based on highly sensitive nanophotonic Si biosensors for single nucleotide DNA testing
In order to solve the drawbacks of sensitivity and portability in optical biosensors we have developed ultrasensitive and miniaturized photonic silicon sensors able to be integrated in a "lab-on-a-chip" microsystem platform. The sensors are integrated Mach-Zehnder interferometers based on TIR optical waveguides (Si/SiO2/Si3N4) of micro/nanodimensions. We have applied this biosensor for DNA testing and for detection of single nucleotide polymorphisms at BRCA-1 gene, involved in breast cancer development, without target labeling. The oligonucleotide probe is immobilized by covalent attachment to the sensor surface through silanization procedures. The hybridization was performed for different DNA target concentrations showing a lowest detection limit at 10 pM. Additionally, we have detected the hybridization of different concentrations of DNA target with two mismatching bases corresponding to a mutation of the BRCA-1 gene. Following the way of the lab-on-a-chip microsystem, integration with the microfluidics has been achieved by using a novel fabrication method of 3-D embedded microchannels using the polymer SU-8 as structural material. The optofluidic chip shows good performances for biosensing
NUEVAS TECNOLOGÍAS APLICADAS A LOS CUESTIONARIOS DE FRECUENCIA DE CONSUMO DE ALIMENTOS: UNA PERSPECTIVA ACTUAL
The food frequency questionnaires are widely used in epidemiological researches like dietary assessment method. Traditionally, they have been self-administered in paper but the use of information and communication technologies has led to develop Internet and computerized food frequency questionnaires. It is the objective of this article to offer a global perspective of the new technologies applied to FFQ. It will be presented the purpose of the food frequency questionnaire, the number of strengths of the web-based surveys versus print-surveys and finally, a description of the manuscripts that have used web-based and computerized FFQ.[ES] Resumen
Los cuestionarios de frecuencia de consumo de alimentos son muy utilizados en investigaciones epidemiológicas
como método para evaluar la dieta. Tradicionalmente,
han sido autoadministrados en papel, pero el uso de las
tecnologías de la información y la comunicación (TICs)
ha permitido desarrollar cuestionarios de frecuencia de
consumo de alimentos computerizados y a través de
Internet. El objetivo de este artículo es ofrecer una perspectiva actual del uso de las nuevas tecnologías aplicadas
al diseño e interpretación de los cuestionarios de frecuencia de consumo de alimentos. En el presente trabajo se
resumen los objetivos de los cuestionarios de frecuencia
de consumo de alimentos, las ventajas de los cuestionarios
autoadministrados por Internet frente a los administrados en papel y finalmente, se describirán diferentes estudios que han usado cuestionarios de frecuencia de consumo de alimentos autoadministrados mediante el uso de
ordenador o a través de Internet.Gonzalez-Carrascosa, R. has a predoctoral scholarship from Generalitat Valenciana (Spain).García Segovia, P.; González Carrascosa, R.; Martínez Monzó, J.; Ngo, J.; Serra-Majem, L. (2011). New technologies applied to food frequency questionnaires: a currentperspective. Nutricion Hospitalaria. 26(4):803-806. doi:10.3305/nh.2011.26.4.5154S80380626
Ajuste psicosocial de adolescentes agresores a través del teléfono móvil y de Internet
El presente estudio tiene como objetivo principal analizar el perfil psicosocial de adolescentes agresores de “cyberbullying”, teniendo en cuenta los siguientes indicadores de ajuste psicosocial: satisfacción con la vida, reputación social no conformista y conductas antisociales dentro y fuera del contexto escolar. La muestra está formada por 896 estudiantes españoles (49.7% chicos y 50.3% chicas), de edades comprendidas entre los 11 y los 19 años (M = 13.9, DT = 1.5). Se encuentran diferencias significativas entre los grupos de ciberagresores y no agresores; los ciberagresores severos, seguidos de los cibereagresores ocasionales, muestran el ajuste psicosocial más conflictivo en todas las variables analizadas, y los adolescentes no agresores el ajuste más adaptado. Estos resultados proporcionan información relevante sobre la importancia del ajuste psicosocial en la prevención e intervención del ciberacoso.Psychosocial profile of perpetrators adolescents through mobile phone and internet. This study’s main objective is to analyze the psychosocial profile of adolescent perpetrators of cyberbullying, taking into account the following indicators of psychosocial adjustment: satisfaction with life, non-conformist reputation and antisocial behavior inside and outside the school context. The sample consisted of 896 Spanish students (49.7% boys and 50.3% girls), aged between 11 and 19 years (M = 13.9, ST = 1.5). There are significant differences between the cyberbullies groups and non-perpetrators adolescents; the severe cyberbullies, followed by occasional cyberbullies, show the most controversial psychosocial adjustment in all the variables analyzed, and teens -perpetrators adolescents show more tailored psychosocial adjustment. These results provide relevant information on the importance of psychosocial adjustment in the prevention and intervention of cyberbullying.peerReviewe
Relations between sexist attitudes, family communication and aggression towards equals
La violencia escolar entre iguales es una problemática con graves consecuencias psicosociales.
Además, se produce en una etapa del ciclo vital en que la familia y las actitudes sexistas tienen cierta
influencia en las conductas violentas de los adolescentes. Desde esta perspectiva, el objetivo del
presente trabajo fue analizar posibles diferencias en el sexismo hostil, sexismo benevolente, comunicación
con la madre y comunicación con el padre entre tres grupos de adolescentes establecidos
según su diferente implicación en violencia hacia los iguales: “baja implicación”, “implicación ocasional”
y “implicación frecuente”. La muestra estuvo compuesta por 1034 adolescentes de ambos
sexos (50.6% chicos y 49.4% chicas), de edades comprendidas entre los 12 y los 18 años. Los
resultados muestran que los adolescentes con una implicación frecuente en conductas de violencia
hacia los iguales presentan más actitudes sexistas benévolas y hostiles y más problemas de comunicación
con ambos progenitores. Asimismo, los implicados en conductas agresivas frecuentes y
ocasionales muestran menos comunicación abierta con la madre y con el padre. Los resultados evidencian
la necesidad de ayudar a los adolescentes que ejercen agresión frecuente hacia sus iguales
e indica la importancia de incluir estas variables en los programas de prevención.Bullying is a problem with serious psychosocial consequences. In addition, it occurs in a stage of
the life cycle in which the family and sexist attitudes have some influence on the violent behavior of
adolescents. From this perspective, the objective of this paper was to analyze possible differences
in hostile sexism, benevolent sexism, communication with the mother and communication with the
father among three groups of adolescents established according to their different involvement in violence
towards peers: “low involvement”, “occasional involvement” and “frequent involvement”. The
sample consisted of 1034 adolescents (50.6% boys and 49.4% girls), between 12 and 18 years old.
The results show that adolescents with a frequent involvement in bullying have more benevolent and
hostile sexist attitudes and more communication problems with both parents. Likewise, those involved
in frequent and occasional aggressive behaviors show less open communication with the mother
and with the father. The results show the need to help adolescents who exercise frequent aggression
and indicate the importance of including these variables in prevention programs.peerReviewe
Recommendations from the Spanish Academy of Dermatology and Venereology Psoriasis Working Group on the Management of Patients with Cancer and Psoriasis
[spa]
Diversos estudios sugieren que los pacientes con psoriasis tienen un mayor riesgo de aparición de neoplasias, especialmente cutáneas, lo que podría estar asociado al uso de terapias para tratar la enfermedad. Además, la evidencia disponible sobre la seguridad de algunos tratamientos en este contexto y el manejo de estos pacientes es escasa. Así, las guías de práctica clínica con recomendaciones para el manejo de la psoriasis en el paciente oncológico son ambiguas. En el presente trabajo se recogen recomendaciones para el manejo y el uso de las terapias disponibles para estos pacientes. Estas recomendaciones han sido consensuadas por 45 dermatólogos del Grupo de Psoriasis de la Academia Española de Dermatología y Venereología utilizando el método Delphi, y tienen por objetivo ayudar a los especialistas en la toma de decisiones en la práctica clínica.[eng]
Several studies suggest that patients with psoriasis have a higher incidence of neoplasms, especially of the skin, which could be associated with the use of therapies to treat psoriasis. Furthermore, the evidence available on the safety profile of some treatments in this context, and the management of these patients is scarce, which is why clinical practice guidelines with recommendations on the management of psoriasis in cancer patients are ambiguous. This study provides recommendations on the management and use of the therapies currently available for these patients. They are the result of a Delphi consensus reached by 45 dermatologists of the Spanish Academy of Dermatology and Venereology Psoriasis Working Group, and their goal is to help specialists in the field in their decision -making processes
Synergy between pyroelectric and photovoltaic effects for optoelectronic nanoparticle manipulation
© 2019 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.The combined action of the pyroelectric (PY) and photovoltaic (PV) effects, exhibited by z-cut LiNbO3:Fe substrates, has been investigated for particle trapping and patterning applications. The novel hybrid procedure provides new possibilities and versatility to optoelectronic manipulation on LiNbO3 substrates. It has allowed obtaining periodic and arbitrary 2D patterns whose particle density distribution is correlated with the light intensity profile but can be tuned through ΔT according to the relative strength of the PV and PY effects. A relevant result is that the PY and PV contributions compete for a ΔT range of 1-20 °C, very accessible for experiments. Moreover, the synergy of the PY and PV has provided two additional remarkable applications: i) A method to measure the PV field, key magnitude for photovoltaic optoelectronic tweezers. Using this method, the minimum field needed to obtain a particle pattern has been determined, resulting relatively high, E~60 kV/cm, and so, requiring highly doped crystals when only using the PV effect. ii) An strategy combining the PY and PV to get particle patterning in samples inactive for PV trapping when the PV field value is under that thresholdMinisterio de Ciencia, Innovación y Universidades of Spain (MAT2014-57704-C3, MAT2017-83951-R); Universidad Politécnica de Madrid (RR01/2016
A protein with simultaneous capsid scaffolding and dsRNA-binding activities enhances the birnavirus capsid mechanical stability
Viral capsids are metastable structures that perform many essential processes; they also act as robust cages during the extracellular phase. Viruses can use multifunctional proteins to optimize resources (e.g., VP3 in avian infectious bursal disease virus, IBDV). The IBDV genome is organized as ribonucleoproteins (RNP) of dsRNA with VP3, which also acts as a scaffold during capsid assembly. We characterized mechanical properties of IBDV populations with different RNP content (ranging from none to four RNP). The IBDV population with the greatest RNP number (and best fitness) showed greatest capsid rigidity. When bound to dsRNA, VP3 reinforces virus stiffness. These contacts involve interactions with capsid structural subunits that differ from the initial interactions during capsid assembly. Our results suggest that RNP dimers are the basic stabilization units of the virion,
provide better understanding of multifunctional proteins, and highlight the duality of RNP as capsidstabilizing and genetic information platformsThis work was supported by grants from the Spanish Ministry of Economy and Competitivity (FIS2011-29493 to PJP, BFU2011-29038 to JLC and BFU2014-55475R to JRC) and Comunidad Autónoma de Madrid (S2013/MIT-2850 to JLC and S2013/MIT-2807 to JRC
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