516 research outputs found
Observations of remotely triggered seismicity in Salton Sea and Coso geothermal regions, Southern California, USA, after big (M_W>7.8) teleseismic earthquakes
A relocated catalog was used to search for changes in seismicity rate in the Salton Sea and the Coso geothermal regions, southern California, USA, during and after large (M_W>7.8) teleseismic earthquakes. Seismicity in these two regions was analyzed within 30- day windows before and after the occurrence of five major earthquakes: the 2002 Denali fault, Alaska (M_W 7.9); the 2004 Sumatra-Andaman (M_W 9.2); the 2010 Central Chile (M_W 8.8); the 2011 Tohoku-Oki, Japan (M_W 9.1); and the 2012 Offshore Northern Sumatra (M_W 8.6) earthquakes.
The Denali (M_W 7.9) earthquake coincided with an increase in seismicity in the Salton Sea region the day when this remote event occurred, indicating that instantaneous triggered seismicity was likely related with the passage of its surface waves. However, in the Coso region the seismicity rate remained approximately constant during the 30-day observation period. The seismicity after the 2004 Sumatra-Andaman (M_W 9.2) earthquake increased in both regions 9 days after the mega-earthquake. The seismicity after the 2010 Chile (M_W 8.8) earthquake increased in both regions approximately 14 days after the remote event. The seismicity in Salton Sea and Coso regions increased 17 and 14 days, respectively, after the 2011 Japan (M_W 9.1) earthquake, suggesting that delayed triggered seismicity was induced after the passage of the surface waves in both regions. Similarly, 6 and 16 days after the 2012 northern Sumatra (M_W 8.6) earthquake the seismicity also increased in Salton Sea and Coso regions, respectively. These observations can be interpreted as evidence of instantaneous and delayed dynamic triggering induced by large remote earthquakes. The maximum magnitude of the delayed triggered swarm increased with the strength (M_0/D) of the mega-earthquake and, the stronger the remote earthquake, the longer the delay time
RDF(S) Interoperability Results for Semantic Web Technologies
Interoperability among different development tools is not a straightforward task since ontology editors rely on specific internal knowledge models which are translated into common formats such as RDF(S). This paper addresses the urgent need for interoperability by providing an exhaustive set of benchmark suites for evaluating RDF(S) import, export and interoperability. It also demonstrates, in an extensive field study, the state of-the-art of interoperability among six Semantic Web tools. From this field study we have compiled a comprehensive set of practices that may serve as recommendations for Semantic Web tool developers and ontology engineers
Apuntes para las clases virtuales que demanda la formación online de ingenieros y licenciados en plataformas Moodle
Con el aumento constante de la virtualidad ha continuado evolucionando el empleo de las plataformas digitales con la preocupación de una formación sólida de los ingenieros y licenciados. El estudio acerca del empleo de las Plataformas Moodle evidencia la necesidad de establecer un adecuado balance entre las actividades y los recursos, con atención al aporte de cada una. En particular se requiere del Taller o Fórum y de Archivos Multimedia para actividades demostrativas e indicar la realización de ejercicios prácticos de simulación que guíen el desarrollo de las competencias afines al perfil de formación del ingeniero o del licenciado.With the constant increase in virtuality, the use of digital platforms has continued to evolve with the concern of a solid training of engineers and graduates. The study on the use of Moodle Platforms shows the need to establish an adequate balance between activities and resources, paying attention to the contribution of each one. In particular, the Workshop or Forum and Multimedia Files are required for demonstration activities and indicate the realization of practical simulation exercises that guide the development of skills related to the training profile of the engineer or graduate
An attenuation study in Southern Italy using local and regional earthquakes recorded by seismic network of Basilicata
We determined a set of empirical functions that describe the spectral amplitude decay of S-waves with distance in Southern Italy. We analyzed 32 earthquakes with magnitudes ML 2.0-5.4 and hypocentral distances ranging between 12 and 216 km. We obtained attenuation functions for 14 frequencies(1.0 5.0 Hz), the spectral amplitudes are above the average. At higher frequencies ( f > 10 Hz), the attenuation functions obtained for Southern Italy are slightly above the standard deviation of the average attenuation functions. It is possible that in this frequency range (10-20 Hz) site effects may influence the amplitude decay. In order to quantify the attenuation of the S-waves, we estimated the quality factor Q modeling the empirical attenuation functions using the following
parametric form: A( f , r)=10/r b·e- pfR/Q ß; where 1.6 = f = 10.0 Hz is the frequency band with minimum effect of instrument
and site response, r = 120 km is the distance range where the rate of decay of the spectral amplitudes is approximately constant, R=(r-10) and ß=3.2 km/s. We found that the exponent b=1.0±0.2 in the frequency
band analyzed and Q shows a frequency dependence that can be approximated by the function Q=32.1 f 1.7
Artrosis postraumática en pacientes con fractura-luxacion de Lisfranc.
La artrosis postraumática es una de las complicaciones más frecuentes y más invalidantes de la
fractura-luxación de Lisfranc (FLL).
Objetivo
. Evaluar el grado de incidencia de artrosis postraumática como
complicación y secuela en pacientes con fractura-luxación de Lisfranc y valorar qué factores muestran relación
directa o influyen en su aparición y desarrollo.
Material y Método
. Se realizó un estudio de cohortes ambispectivo
transversal de 83 pacientes con diagnóstico de fractura-luxación de Lisfranc. Se utilizó un protocolo de recogida
de datos con variables relacionadas con la lesión, parámetros clínicos, terapéuticos, complicaciones y escalas de
valoración clínica. La valoración de artrosis se realiza mediante aparición de signos radiológicos de la clasifica
-
ción radiológica de Kellgren y Lawrence y su correlación clínica con presencia de dolor.
Resultados
. La artrosis
se mostró como un factor influyente en los resultados, puntuaciones regulares y malas presentan mayor tasa de
artrosis (p=0,001), y en cuanto al grado de artrosis, los casos más graves de artrosis se situaban en el grupo de
puntuaciones malas (p=0,025). Este grupo de pacientes presentaron peores puntuaciones porque referían más
dolor, mayor consumo de analgésicos, más limitación de las actividades de la vida diaria, de las actividades
deportivas y limitación de la distancia caminada.
Conclusiones
. La artrosis se mostró como un factor influyente
en los resultados (p=0,001). Los pacientes que desarrollaron artrosis tardaron más tiempo en reincorporarse a
su empleo o actividad laboral previa, tenían un tiempo más demorado desde la cirugía al alta y mayor número
total de incapacidades laborales y compensaciones económicas con respecto a los pacientes que no desarrollaron
artrosis, siendo todos estos valores estadísticamente significativos.The posttraumatic degenerative osteoarthritis is one of the most frequent complications and more
disabling of Lisfranc's fracture - luxation (FLL).
Objetive. Evaluate the degree of frequency of posttraumatic
degenerative osteoarthritis as complication and adverse effect in patients with Lisfranc's fracture - luxation and
value what factors show straight relation or influence in its appearance and development.
Material and Method.We have made a transversal prospective and retrospective study of cohorts on 83 patients with diagnosis of
Lisfranc's fracture - luxation. We have used a data collecting protocol of items related to the injury, clinical,
therapeutic parameters, complications and scales of clinical valuation. The assessment valuation of degenerative
osteoarthritis is made under radiological signs realized by means of appearance of radiological signs of Kellgren
and Lawrence classification and clinical correlation with presence of pain.
Results
. The degenerative osteoarthri
tis appeared as an influential factor in the results, regular and bad punctuations present major rate of degenerative
osteoarthritis (p=0,001), and as for the degree of degenerative osteoarthritis, the most serious cases of degenerative osteoarthritis were placing in the group of bad punctuations (p=0,025). This group of patients presented
worse punctuations because they were recounting more pain, major consumption of analgesics, more limitation
of the activities of the daily life, of the sports activities and limitation of the travelled distance.
Conclusions
. The
degenerative osteoarthritis appeared as an influential factor in the results (p=0,001). The patients who developed
degenerative osteoarthritis were late more time in coming back to his employment or labor previous activity;
they had a time more delayed from the surgery to the discharge and major total number of labor disabilities and
economic compensations with regard to the patients who did not develop degenerative osteoarthritis, being all
these statistically significant values
Triggered release of proteins from emulsan–alginate beads
Emulsan/alginate beads were studied for protein adsorption and stability in the context of controlled release. The beads, 400F80 Am diameter with approximately 10% emulsan content, offer unusual opportunities for delivery of proteins due to the natural ability of emulsan to bind proteins, coupled with the selective biological activation features of this complex lipoheteropolysaccharide. The binding capacity of azo-bovine serum albumin by the emulsan/alginate beads was 0.637 ± 0.004 vs. 0.170 ± 0.007 μg/mg for beads formed from alginate alone. In additional protein adsorption experiments, the lipase and subtilisin maintained activity when adsorbed to the emulsan/alginate beads albeit with lower specific activity when compared to the enzyme free in solution. However, the half life of the adsorbed enzyme was significantly higher than the free forms. To explore functional utility of this system, two types of triggered release were studied in the context of these bead systems. First, azo-BSA as a model protein was physically bound to emulsan/alginate beads and then selectively released by triggering with subtilisin, a serine protease, which cleaves the azo dye, sulfanilic acid, from the bound protein. In absence of subtilisin no triggered release was observed. Second, azo-BSA as a prodrug model, was adsorbed to the emulsan/alginate beads and then release of the dye was demonstrated by lipase treatment which cleaves the fatty acid esters from the emulsan structure to release the bound protein. The results establish the versatility and utility of emulsan-based beads for protein binding and triggered release.Centro de Investigación y Desarrollo en Fermentaciones Industriale
Alcohol from tropical fruit residues
Foram estudados os rendimentos em álcool de cascas de frutos tropicais (banana, abacaxi e tangerina) em extratos contendo açúcares fermentáveis obtidos mediante extração aquosa a quente e em solução ácida diluída (6,7%) e concentrada (35% e 41%). Na fermentação - feita em escala de laboratório - empregou-se a levedura Saccharomyces cerevisiae. O aproveitamento dos açúcares variou de 96% a 100% no caso da extração em água quente, sendo estes valores inferiores na extração com ácido clorídrico diluído. Foi estimada uma média de 12,6 l de álcool por t de casca de banana, de 68,7 l/t de casca de tangerina e de 100,6 l por t de casca de abacaxi, nas extrações com água quente. Estes valores caíram, na extração com ácido diluído, para 12 l/t no caso de banana, 10 l/t no abacaxi, e 26 l/t no da casca de tangerina. Num processo de extração combinado de água com ácido concentrado foram obtidos rendimentos da ordem de 13 l/t (abacaxi), 9,5 l/t (tangerina) e 7,8 l/t (banana). O rendimento em álcool foi de 72,1% para banana, 98,2% para abacaxi e 98,0% para tangerina no caso de extração com água quente. Estes valores foram reduzidos para 59%, 34% e 43%, respectivamente, na extração ácida diluída e no processo combinado, para 64,3%, 32,9% e 65,1% na mesma ordem. Alcohol production from peel extracts of tropical fruits (banana, pineapple and mandarin oranges) having fermentable sugars extracted with hot water and HCl solutions (6.7% and a combined 35% and 41%) was studied. For the fermentation of the extract the yeast Saccharomyces cerevisiae was used. The sugar utilization varied from 96% to 100% for hot water extraction being this value lower for the HCl extractions. Alcohol productions were 12.6 liters per ton in the case of banana, 68.7 liters per ton for mandarins, and 100.6 liters per ton for pineapple, for the hot water extractions. These values dropped to 12 liters per ton in banana, 10 liters per ton in pineapple and 26 liters per ton in orange peels for the diluted acid extraction. For an extraction process using a combination of hot water and concentrated acid, yields were 13 l/ton for pineapple, 9.5 l/ton for mandarin and 7.8 l/ton for banana peels. The alcoholic yields were estimated as 72.1% for banana, 98.2% for pineapple and 98.0% for mandarins, for the hot water extraction. These values were reduced to 59%, 34% and 43%, respectively, in the diluted acid extraction, and to 64.3%, 32.9% and 65.1% in the same order, for the combined process.
Evaluación actual y propuestas para el desarrollo urbano en México
La revista Problemas del Desarrollo recoge en su colección de ediciones especiales las disertaciones y ponencias que se presentan en los seminarios, simposia y conferencias a que convoca y realiza anualmente el Instituto de Investigaciones Económicas de la Universidad Nacional Autónoma de México.
El propósito es contribuir a la mayor difusión de textos de contenido analítico, descriptivo y propositivo que se presentan en tales actos y que tienen gran valor para el mejor conocimiento y comprensión de la estructura y problemática económica y social de nuestro país. Pero también la revista quiere convertirse en foro abierto para la expresión de comentarios y ampliaciones que deseen hacer los lectores de estas ediciones especiales sobre temas particulares de los comprendidos en cada uno de sus libros. Estos aportes, por lo tanto, serán muy bien recibidos. Para ello, solo se requiere que los lectores los remitan, por escrito, al Instituto de Investigaciones Económicas, Torre II de Humanidades, Ciudad Universitaria
Bioeconomic multistock reference points as a tool for overcoming the drawbacks of the landing obligation
The landing obligation policy was one of the major innovations introduced in the last Common Fisheries Policy reform in Europe. It is foreseen that the policy will affect the use of fishing opportunities and hence the economic performance of the fleets. The problem with fishing opportunities could be solved if single-stock total allowable catches (TACs) could be achieved simultaneously for all the stocks. In this study, we evaluate the economic impact of the landing obligation policy on the Spanish demersal fleet operating in the Iberian Sea region. To generate TAC advice, we used two sets of maximum sustainable yield (MSY) reference points, the single-stock MSY reference points defined by ICES and a set of multistock reference points calculated simultaneously using a bioeconomic optimization model. We found that the impact of the landing obligation is time and fleet dependent and highly influenced by assumptions about fleet dynamics. At fishery level, multistock reference points mitigate the decrease in the net present value generated by the implementation of the landing obligation. However at fleet level, the effect depends on the fleet itself and the period. To ensure the optimum use of fishing opportunities, the landing obligation should be accompanied by a management system that guarantees consistency between single-stock TACs. In this regard, multistock reference points represent an improvement over those currently in use. However, further investigation is necessary to enhance performance both at fleet level and in the long term.Versión del edito
Bacterial cellulose-based materials as dressings for wound healing
Bacterial cellulose (BC) is produced by several microorganisms as extracellular structures and can be modified by various physicochemical and biological strategies to produce different cellulosic formats. The main advantages of BC for biomedical applications can be summarized thus: easy moldability, purification, and scalability; high biocompatibility; and straightforward tailoring. The presence of a high amount of free hydroxyl residues, linked with water and nanoporous morphology, makes BC polymer an ideal candidate for wound healing. In this frame, acute and chronic wounds, associated with prevalent pathologies, were addressed to find adequate therapeutic strategies. Hence, the main characteristics of different BC structures—such as membranes and films, fibrous and spheroidal, nanocrystals and nanofibers, and different BC blends, as well as recent advances in BC composites with alginate, collagen, chitosan, silk sericin, and some miscellaneous blends—are reported in detail. Moreover, the development of novel antimicrobial BC and drug delivery systems are discussed.Centro de Investigación y Desarrollo en Fermentaciones Industriale
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