92 resultados para Chemical technologies
Resumo:
Background: Huntington's disease (HD) is an inherited neurodegenerative disorder triggered by an expanded polyglutamine tract in huntingtin that is thought to confer a new conformational property on this large protein. The propensity of small amino-terminal fragments with mutant, but not wild-type, glutamine tracts to self-aggregate is consistent with an altered conformation but such fragments occur relatively late in the disease process in human patients and mouse models expressing full-length mutant protein. This suggests that the altered conformational property may act within the full-length mutant huntingtin to initially trigger pathogenesis. Indeed, genotypephenotype studies in HD have defined genetic criteria for the disease initiating mechanism, and these are all fulfilled by phenotypes associated with expression of full-length mutant huntingtin, but not amino-terminal fragment, in mouse models. As the in vitro aggregation of amino-terminal mutant huntingtin fragment offers a ready assay to identify small compounds that interfere with the conformation of the polyglutamine tract, we have identified a number of aggregation inhibitors, and tested whether these are also capable of reversing a phenotype caused by endogenous expressionof mutant huntingtin in a striatal cell line from the HdhQ111/Q111 knock-in mouse. Results: We screened the NINDS Custom Collection of 1,040 FDA approved drugs and bioactive compounds for their ability to prevent in vitro aggregation of Q58-htn 1¿171 amino terminal fragment. Ten compounds were identified that inhibited aggregation with IC50 < 15 ¿M, including gossypol, gambogic acid, juglone, celastrol, sanguinarine and anthralin. Of these, both juglone and celastrol were effective in reversing the abnormal cellular localization of full-length mutant huntingtin observed in mutant HdhQ111/Q111 striatal cells. Conclusions: At least some compounds identified as aggregation inhibitors also prevent a neuronal cellular phenotype caused by full-length mutant huntingtin, suggesting that in vitro fragment aggregation can act as a proxy for monitoring the disease-producing conformational property in HD. Thus, identification and testing of compounds that alter in vitro aggregation is a viable approach for defining potential therapeutic compounds that may act on the deleterious conformational property of full-length mutant huntingtin.
Resumo:
This study was aimed to analyze and assess the use and perception of electronic health records (EHRs) by nurses. The study sample included 113 nurses from different shifts of primary health facilities in Catalonia, Spain, devoted to adult as well as pediatric outpatients using EHRs throughout the year 2010. A majority of the sample (87.5%) were women and 12.5% were men. The average age was 44.27 years and the average time working in primary healthcare was 47.15 months. A majority (80.4%) received specific training on the use of the EHR and 19.6% did not. The use of the application required side technical support (mean: 3.42) and it is considered necessary to learn more about the performance of the application (mean: 3.50). The relationship between the average ratings that nurses have about the EHR and age shows that there is no statistically significant linear relationship (r = - 0.002, p-value = 0.984). As to how long they have used the EHRs, there are significant differences (r= -0.304, p-value = 0.00), so the more time the nurse takes using the EHR, the greater degree of satisfaction is shown. In addition, there are significant differences between nurses" perceptions regarding the EHR and gender (t = - 0.421, p-value = 0.675). Nurses assessed as positive the contribution of the EHRs in their nursing care day work (average score: 2.55/5). Considering that the usability of the EHR device is assessed as satisfactory, the results of the perception of nurses show that we must also take into account the training and emphasize the need for a side technical support in the implementation process of the EHR. Doing so, the positive perception that nurses have in regard to information and communication technology in general and with respect to the EHR in particular may be increased.
Resumo:
This study was aimed to analyze and assess the use and perception of electronic health records (EHRs) by nurses. The study sample included 113 nurses from different shifts of primary health facilities in Catalonia, Spain, devoted to adult as well as pediatric outpatients using EHRs throughout the year 2010. A majority of the sample (87.5%) were women and 12.5% were men. The average age was 44.27 years and the average time working in primary healthcare was 47.15 months. A majority (80.4%) received specific training on the use of the EHR and 19.6% did not. The use of the application required side technical support (mean: 3.42) and it is considered necessary to learn more about the performance of the application (mean: 3.50). The relationship between the average ratings that nurses have about the EHR and age shows that there is no statistically significant linear relationship (r = - 0.002, p-value = 0.984). As to how long they have used the EHRs, there are significant differences (r= -0.304, p-value = 0.00), so the more time the nurse takes using the EHR, the greater degree of satisfaction is shown. In addition, there are significant differences between nurses" perceptions regarding the EHR and gender (t = - 0.421, p-value = 0.675). Nurses assessed as positive the contribution of the EHRs in their nursing care day work (average score: 2.55/5). Considering that the usability of the EHR device is assessed as satisfactory, the results of the perception of nurses show that we must also take into account the training and emphasize the need for a side technical support in the implementation process of the EHR. Doing so, the positive perception that nurses have in regard to information and communication technology in general and with respect to the EHR in particular may be increased.
Resumo:
Este trabajo persigue dos objetivos: el primero es analizar el uso de las TIC en un grupo de estudiantes de segundo curso de Magisterio de la Universidad de Girona; el segundo es analizar los documentos normativos legales que establecen el currículum de educación primaria en Cataluña para observar qué tipo de papel juegan las TIC en las nuevas programaciones educativas. La primera parte se ha llevado a cabo mediante una encuesta, cuyos resultados permiten observar tres aspectos distintos: el primero, que una parte considerable del grupo considera las TIC más como un complemento para el aprendizaje que como una forma de aprendizaje; el segundo, que a pesar de hacer un uso considerable de las TIC, el conocimiento que tienen de ellas es muy básico y utilizan aplicaciones muy genéricas; y el tercero es que una parte de sus propuestas didácticas para el uso de las TIC son propuestas tradicionales simplemente adaptadas a un nuevo instrumento, sin buscar realmente la innovación que puede suponer la incorporación de las TIC. En la segunda parte del artículo, a partir del análisis e interpretación de los documentos legales que establecen el currículum de Educación Primaria, se observa que en un mismo documento conviven aserciones sobre las TIC como complemento al aprendizaje de contenidos con otras formulaciones que consideran las TIC como constructoras de conocimiento. A partir del perfil de los estudiantes y del estado de los documentos legales, al final del artículo se hacen propuestas para formar al futuro maestro teniendo en cuenta las TIC como herramientas básicas de conocimiento
Resumo:
Majolica pottery was the most characteristic tableware produced in Europe during the Medieval and Renaissance periods. Because of the prestige and importance attributed to this ware, Spanish majolica was imported in vast quantities into the Americas during the Spanish Colonial period. A study of Spanish majolica was conducted on a set of 186 samples from the 10 primary majolica production centres on the Iberian Peninsula and 22 sherds from two early colonial archaeological sites on the Canary Islands. The samples were analysed by neutron activation analysis (NAA), and the resulting data were interpreted using an array of multivariate statistical approaches. Our results show a clear discrimination between different production centres, allowing a reliable provenance attribution of the sherds from the Canary Islands.
Resumo:
The main objective of this research was to study the feasibility of incorporating organosolv semi-chemical triticale fibers as the reinforcing element in recycled high density polyethylene (HDPE). In the first step, triticale fibers were characterized in terms of chemical composition and compared with other biomass species (wheat, rye, softwood, and hardwood). Then, organosolv semi-chemical triticale fibers were prepared by the ethanolamine process. These fibers were characterized in terms of its yield, kappa number, fiber length/diameter ratio, fines, and viscosity; the obtained results were compared with those of eucalypt kraft pulp. In the second step, the prepared fibers were examined as a reinforcing element for recycled HDPE composites. Coupled and non-coupled HDPE composites were prepared and tested for tensile properties. Results showed that with the addition of the coupling agent maleated polyethylene (MAPE), the tensile properties of composites were significantly improved, as compared to non-coupled samples and the plain matrix. Furthermore, the influence of MAPE on the interfacial shear strength (IFSS) was studied. The contributions of both fibers and matrix to the composite strength were also studied. This was possible by the use of a numerical iterative method based on the Bowyer-Bader and Kelly-Tyson equations
Resumo:
Amber from a Lower Cretaceous outcrop at San Just, located in the Eastern Iberian Peninsula (Escucha Formation, Maestrat Basin), was investigated to evaluate its physico-chemical properties. Thermogravimetric (TG) and Differential Thermogravimetric (DTG) analyses, infra-red spectroscopy, elemental and C-isotope analyses were performed. Physico-chemical differences between the internal light nuclei and the peripheral darker portions of San Just amber can be attributed to processes of diagenetic alteration that preferentially took place in the external amber border colonized by microorganisms (fungi or bacteria) when the resin was still liquid or slightly polymerized. δ13Camber values of different pieces of the same sample, from the nucleus to the external part, are remarkably homogeneous, as are δ13Camber values of the darker peripheral portions and lighter inner parts of the same samples. Hence, neither invasive microorganisms, nor diagenetic alteration, changed the bulk isotopic composition of the amber. δ13C values of different amber samples range from -21.1 to -24 , as expected for C3 plant-derived material. C-isotope analysis, coupled to palaeobotanical, TG and DTG data and infra-red spectra, suggests that San Just amber was exuded by only one conifer species, belonging to either the Cheirolepidiaceae or Aracauriaceae, coniferous families probably living under stable palaeoenvironmental and palaeoecological conditions.
Resumo:
Previous results concerning radiative emission under laser irradiation of silicon nanopowder are reinterpreted in terms of thermal emission. A model is developed that considers the particles in the powder as independent, so under vacuum the only dissipation mechanism is thermal radiation. The supralinear dependence observed between the intensity of the emitted radiation and laser power is predicted by the model, as is the exponential quenching when the gas pressure around the sample increases. The analysis allows us to determine the sample temperature. The local heating of the sample has been assessed independently by the position of the transverse optical Raman mode. Finally, it is suggested that the photoluminescence observed in porous silicon and similar materials could, in some cases, be blackbody radiation
Resumo:
The quenching of the photoluminescence of Si nanopowder grown by plasma-enhanced chemical vapor deposition due to pressure was measured for various gases ( H2, O2, N2, He, Ne, Ar, and Kr) and at different temperatures. The characteristic pressure, P0, of the general dependence I(P)=I0exp(-P/P0) is gas and temperature dependent. However, when the number of gas collisions is taken as the variable instead of pressure, then the quenching is the same within a gas family (mono- or diatomic) and it is temperature independent. So it is concluded that the effect depends on the number of gas collisions irrespective of the nature of the gas or its temperature
Resumo:
In a previous work, a hybrid system consisting of an advanced oxidation process (AOP) named Photo-Fenton (Ph-F) and a fixed bed biological treatment operating as a sequencing batch biofilm reactor (SBBR) was started-up and optimized to treat 200 mg·L-1 of 4-chlorophenol (4-CP) as a model compound. In this work, studies of reactor stability and control as well as microbial population determination by molecular biology techniques were carried out to further characterize and control the biological reactor. Results revealed that the integrated system was flexible and even able to overcome toxic shock loads. Oxygen uptake rate (OUR) in situ was shown to be a valid tool to control the SBBR operation, to detect toxic conditions to the biomass, and to assess the recovery of performance. A microbial characterization by 16S rDNA sequence analysis reveals that the biological population was varied, although about 30% of the bacteria belonged to the Wautersia genus.
Resumo:
Resum L’any 1969 es van començar a comercialitzar els sistemes digitals programables coneguts com autòmats programables o PLC’s, utilitzats per controlar qualsevol tipus de procés industrial. Al llarg de tots aquests anys, aquests sistemes i tota la tecnologia en general han evolucionat molt, i només és qüestió de temps que la tecnologia que utilitzem avui en dia quedi obsoleta i substituïda per una de millors característiques i amb més avantatges. Aquest és el motiu de l’elaboració d’aquest treball, que com a objectiu pretén modernitzar un procés de fabricació d’una industria química que ha quedat molt limitat a causa de l’antiguitat de la instal•lació. Per dur a terme aquesta modernització, s’introdueixen sistemes de control amb majors prestacions, s’utilitzen xarxes de comunicacions per facilitar el muntatge elèctric de la instal•lació i un sistema de supervisió i adquisició de dades per poder obtenir un control més estricte del procés de fabricació i de tots els factors que intervenen. El funcionament del procés de fabricació és que a partir d’unes matèries primeres líquides emmagatzemades en dipòsits, es dosifiquin aquestes matèries en l’ordre i la quantitat desitjada dins un o diversos recipients per barrejar-les i aplicar els tractaments que siguin necessaris. Tot aquest procés està controlat per un autòmat programable, i disposa de diferents terminals operadors per poder interactuar amb el sistema. També té implementat un sistema SCADA en diversos ordinadors per aportar una visió general de la planta en temps real, un registre de dades dels paràmetres que es controlen i alhora serveix per enllaçar amb la xarxa d’ordinadors existent. Com annex d’aquest treball, es presenten els esquemes elèctrics i el programa de l’autòmat programable per veure totes les característiques elèctriques dels dispositius i el mètode de funcionament del procés. S’ha aconseguit donar un salt tecnològic i poder gaudir de tots els avantatges que ofereixen les noves tecnologies, que com a resultat s’ha optimitzat i millorat el procés de fabricació. De totes les conclusions, la més destacada és la d’haver dissenyat un sistema de control basat en una estructura descentralitzada molt flexible, que es pot expandir i adaptar fàcilment als possibles canvis.
Resumo:
Sobre el impacto que las TIC pueden tener en las relaciones interpersonales, ya sean en la familia y/o con los amigos/as, desde una perspectiva psicosocial
Resumo:
The presented itinerary covers eleven sites of the city of Girona that have been chosen for their interest from a chemical point of view. Girona is a city with chemistry, and this journey allowed student to see that chemistry is present everywhere, even in everyday life and not only in classrooms and laboratories. This approach aims to motivate students to discover something that had been invisible
Resumo:
The high sensitivity and excellent timing accuracy of Geiger mode avalanche photodiodes makes them ideal sensors as pixel detectors for particle tracking in high energy physics experiments to be performed in future linear colliders. Nevertheless, it is well known that these sensors suffer from dark counts and afterpulsing noise, which induce false hits (indistinguishable from event detection) as well as an increase of the necessary area of the readout system. In this work, we present a comparison between APDs fabricated in a high voltage 0.35 µm and a high integration 0.13 µm commercially available CMOS technologies that has been performed to determine which of them best fits the particle collider requirements. In addition, a readout circuit that allows low noise operation is introduced. Experimental characterization of the proposed pixel is also presented in this work.