1,298 research outputs found
Propiedades, ventajas e inconvenientes de los materiales utilizados en supercondensadores
Este trabajo recoge una visión general de las propiedades, ventajas e inconvenientes de los principales materiales usados en los electrodos de los condensadores electroquímicos (también denominados supercondensadores). La elección de estos materiales tiene una enorme influencia en las características finales del dispositivo electroquímico. Entre los materiales de electrodo disponibles para su aplicación en supercondensadores se incluyen los materiales porosos basados en carbón, los óxidos de metales de transición y los polímeros conductores. Cada una de estas familias de materiales presenta unas ventajas e inconvenientes, por ello, en numerosas ocasiones no se emplea un único tipo de material para la elaboración de los electrodos, sino que la tendencia va dirigida hacia el uso de electrodos híbridos, es decir, aquellos constituidos por materiales de distinta naturaleza que combinan los aspectos beneficiosos y compensan las limitaciones de cada uno de los materiales por separado
Suppression of the sterility in insulin signaling pathway mutants of Caenorhabditis elegans
Mutants in the insulin signaling pathway are related with a low or null fertility in Caenorhabditis elegans. This pathway is conserved through evolution in all metazoans, and similarly to C. elegans, deficiencies in insulin signaling pathway activity result in a decreased fertility in other organisms including humans. We have previously selected a strain that carries a mutation in the age-1 gene (orthologue to human PI3K) which has a severe reduced fertility phenotype. Using this strain it was performed a screening for genes that when removed by RNAi suppressed the sterility, using for that only genes that were orthologue to human. Most of genes whose reversion was significantly different were genes involved in the initiation of the transcription (eIF). Those genes encode to non-specific non-ribosomally associated proteins involved in the initiation phase of eukaryotic translation. The aim of this project is to better understand the relationship between fertility and the expression of eIF genes and why RNAi of only a few of them can improve fertility and not others. On the other hand, I’m searching for drugs that improve the fertility of the nematode similarly to RNAi that could be used in future human therapies.
Adults' Lack of a Usual Source of Care: A Matter of Preference?
PURPOSE We wanted to identify characteristics of adults who do not have a usual source of care and then stratify the analysis by those who prefer vs those who do not prefer to have a usual source of care
Recommended from our members
Finding SQL Injection and Cross Site Scripting Vulnerabilities with Diverse Static Analysis Tools
The use of Static Analysis Tools (SATs) is mandatory when developing secure software and searching for vulnerabilities in legacy software. However, the performance of the various SATs concerning the detection of vulnerabilities and false alarm rate is usually unknown and depends on many factors. The simultaneous use of several tools should increase the detection capabilities, but also the number of false alarms. In this paper, we study the problem of combining several SATs to best meet the developer needs. We present results of analyzing the performance of diverse static analysis tools, based on a previously published dataset that resulted from the use of five diverse SATs to find two types of vulnerabilities, namely SQL Injections (SQLi) and Cross-Site Scripting (XSS), in 132 plugins of the WordPress Content Management System (CMS). We present the results based on well-established measures for binary classifiers, namely sensitivity and specificity for all possible diverse combinations that can be constructed using these 5 SAT tools. We then provide empirically supported guidance on which combinations of SAT tools provide the most benefits for detecting vulnerabilities with low false positive rates
Assessment of motor coordination in primary education of Barcelona and province
El presente estudio tiene por objetivo valorar la coordinación motora de estudiantes de primaria de Barcelona y provincia. Para la evaluación se ha utilizado el test KTK en el que participaron 1254 personas, 670 niños y 584 niñas, de edades entre 7 y 10 años. Se realizó el análisis descriptivo y la comparación entre género y edad. Los resultados indican que más del 40% de la población estudiada presenta una coordinación por debajo de la normalidad, cerca de un 57% de la muestra fue clasificado con coordinación normal y solamente el 4,6%
lo ha sido por encima de esta clasificación. Los chicos han presentado resultados significativamente mejores que las chicas. Los datos del estudio no permiten generalizar los resultados, sin embargo como es una muestra representativa, nos lleva a creer que la población de alumnos en educación primaria de Barcelona y su provincia tiene un nivel coordinativo por debajo del esperado para su edadThe present study aims to assess motor coordination of primary-school students of Barcelona and its province. For evaluation we used the KTK test. 1254 people, 670 boys and 584 girls with ages between 7 and 10 years participated in the study. Descriptive analysis and the comparison between gender and age were performed. The results indicate that about 40% of the population studied presents results below normal, around 57% were classified with normal coordination and only 4.6% has been above this rating. The boys have presented significantly better results than girls. The study data do not permit to generalize the results, however as a representative sample, it leads us to believe that the student population in elementary education from Barcelona and its province has a coordinative level below expected for their ageAgrupació de Recerca en Ciències de l’Educació. U
Potential Effect of Physical Activity Calorie Equivalent Labeling on Parent Fast Food Decisions
Menu labels displaying food energy in physical activity calorie equivalents (PACE) is a possible strategy to encourage ordering meals with fewer calories and promoting physical activity. Potential effects of such labeling for children have never been examined
Signature of chaos in gravitational waves from a spinning particle
A spinning test particle around a Schwarzschild black hole shows a chaotic
behavior, if its spin is larger than a critical value. We discuss whether or
not some peculiar signature of chaos appears in the gravitational waves emitted
from such a system. Calculating the emitted gravitational waves by use of the
quadrupole formula, we find that the energy emission rate of gravitational
waves for a chaotic orbit is about 10 times larger than that for a circular
orbit, but the same enhancement is also obtained by a regular "elliptic" orbit.
A chaotic motion is not always enhance the energy emission rate maximally. As
for the energy spectra of the gravitational waves, we find some characteristic
feature for a chaotic orbit. It may tell us how to find out a chaotic behavior
of the system. Such a peculiar behavior, if it will be found, may also provide
us some additional informations to determine parameters of a system such as a
spin.Comment: 14 pages, LaTeX, to appear in Phys. Rev.
Designing research tools : empirical knowledge as a base for future beekeeping.
The world-wide phenomenon of the disappearance of bees with the consequential imbalance of ecosystems is a problem that needs to be addressed in order to guarantee a sustainable future. Beekeeping is an activity, generally associated to agriculture, that allows small farmers to generate more food and income, this reality has had a shift in recent years with the number of small beekeepers decreasing, and big corporations gaining control over the industry. Regulations and the Colony Collapse Disorder, among other factors, may have a major role in these phenomena.
With the intent to contribute to a more sustainable beekeeping practice, this research is being conducted to better understand this reality, looking for design driven opportunities.
The challenge is to gain a deeper understanding of the beekeepers, a practice that is understudied by designers, particularly considering in-depth research methods. This paper discusses an experimental design study in the Turkish Aegean region that was conducted with local beekeepers to better understand the existing specifications: by discussing their business models, in order to understand and analyze socio-cultural factors that contributed to the existing system, and propose changes for a more sustainable practice. As a starting point for a first phase survey, the intent is to generate original data which will serve as the foundation for future works.
Beekeepers in this scenario are mainly senior male farmers that belong to a low literacy audience, who learned the practice from their predecessors. In order to identify the problems of beekeepers, we needed to design and adjust our research methods according to the specifications of the audience. For this reason, a three stage inquiry was designed to better communication in order to extract measurable data from their empirical knowledge through a series of workshops.
The case study reports the workshop sessions for identifying the design strategies with a focus on voicing the beekeepers problems. The first level draws upon explicit knowledge to identify the audience. For the second level an illustrated questionnaire was designed to visually represent the quantitative data about the business. The process is exercised with a new design because the content of knowledge is tacit and personal. Finally, the third level is an interview session to validate the data gathered from the previous stages.
This paper will present the findings of the workshops with the aim to formulate an appropriate way to employ new approaches to exploring and defining design problems with visual representations. We also seek to extend our research in other contexts that will help discuss the role of design as a tool for developing new methodologies of design research.
As a consequence we will propose prototypes of artifacts that will consider the implementation into beekeeping of new biomaterials, technology, branding and commercialization planning, etc., that may help create a more sustainable beekeeping practice. Beekeepers will be invited to analyze proposals and give their contributions. This process will render into redesigned optimized artifacts that will merge empirical knowledge with the needs of sustainable beekeeping.
Keywords design research tools, beekeeping, sustainability, eco-innovation, cooperatio
- …