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Business model responses to digital piracy
Digital piracy challenges firms by reducing revenues and shifting consumption habits. Recently, some firms have successfully leveraged business models against piracy, but the understanding about this phenomenon still lacks depth and structure. This study examines the characteristics of digital piracy in some of the most affected industries, presents comparative case studies of two iconic firms, Spotify and Netflix, and analyzes their digital business model responses. We generalize their adoption to generic digital content distributors and explain how they contribute to generate and capture value. Theoretical and practical implications for technological innovation, firm diversification, and network competition are also discussed
Computed tomography angiography, perforator flaps, surgeon and OsiriX
Desde la introducción de la transferencia cutánea basada en perforantes,
la angiotomografía computerizada ha emergido como una técnica
de gran valor en la planificación preoperatoria de los colgajos de perforante.
Sin embargo, parece probable que el aprovechamiento de la técnica
sea menor del deseable.
Evaluamos, a través de la experiencia en 144 pacientes, la utilidad del
visor gratuito de imágenes DICOM OsiriX para Mac en la planificación
preoperatoria de los colgajos de perforante con tres objetivos: 1) ampliar
los conocimientos actuales relacionados con la aplicación de la angiotomografía
computerizada en la planificación preoperatoria de los colgajos
de perforante, 2) evaluar la aplicación OsiriX en el post-procesamiento
de imágenes en la planificación preoperatoria de colgajos de perforante y
3) evaluar el rendimiento obtenible de la angiotomografía considerando
que el postprocesamiento es realizado por un cirujano (no especialista en
Radiodiagnóstico).
La experiencia permite afirmar que el postprocesamiento de las imágenes
DICOM por el cirujano con la aplicación Osirix permite habitualmente
evaluar de manera adecuada diversas estructuras y parámetros de
gran interés en la cirugía de colgajos de perforante: 1) arteria principal, origen
de la perforante, 2) diámetro de arteria y vena/s en el hipotético sitio de
anastomosis microquirúrgica, 3) recorrido y patrón de ramificación del pedículo
del colgajo, 4) disposición de la perforante en la grasa subcutánea
(teórico eje de diseño del colgajo), 5) medición del grosor cutáneo en el
punto de perforación de la fascia profunda por la rama perforante (teórico
grosor de colgajo), 6) medición de la distancia entre el punto de perforación
de la fascia profunda por la rama perforante y el origen de la arteria
principal (teórica longitud máxima posible de pedículo) y 7) medición del
diámetro, en el punto de perforación de la fascia profunda, de la perforante.
En consecuencia, parece aconsejable que el cirujano plástico relacionado
con los colgajos de perforante se involucre decididamente en el postprocesamiento
de las imágenes de angiotomografía computerizada. El
visor de imágenes DICOM gratuito OsiriX es una alternativa eficiente,
comparable a aplicaciones más profesionales sólo disponibles en servicios
de Radiología.With the advent of perforator-based skin transfer, computed tomography
angiography has emerged as an invaluable tool in the preoperative
planning of perforator flaps. But most likely, the exploitation of the
technique is less than desirable.
Through our experience with 144 patients, we evaluate the use of the
free DICOM viewer OsiriX for Mac in the preoperative planning of perforator
flaps with three objectives: 1) increase the present knowledge related
with the preoperative planning of perforator flaps with computed
tomography angiography, 2) evaluate the OsiriX application in the image
post-processing of perforator flaps and 3) evaluate the performance of the
procedure when performed by a surgeon (not specialized in Radiology).
The experience has shown that the image post-processing performed
by the surgeon with the OsiriX application usually allows an adequate
evaluation of different structures and parameters of great preoperative interest
in perforator flap surgery: 1) source artery, 2) diameter of artery and
vein/s at the hypothetical site of microsurgical anastomoses, 3) course and
branching pattern of the flap pedicle, 4) perforator course in the subcutaneous
fat (theoretical flap axis), 5) measurement of the skin and fat where
the perforator pierces the deep fascia (theoretical flap thickness ), 6) measurement
of the distance between the point of entrance of the perforator
in the subcutaneous fat to the source artery (theoretical maximal pedicle
length) and 7) measurement of the perforator diameter where it pierces
the deep fascia.
Ultimately, in the authors’ opinion, those plastic surgeons involved in
perforator flap surgery would largely benefit from incorporating the image
post-processing into their routine practice. The free DICOM viewer
OsiriX is an efficient alternative, comparable to the more professional
software only available in Radiology service
Optimal sizing of a heat pump booster for sanitary hot water production to maximize benefit for the substitution of gas boilers
[EN] Heat recovery from water sources such as sewage water or condensation loops at low temperatures (usually between 10 and 30 °C) is becoming very valuable. Heat pumps are a potential technology able to overcome the high water temperature lift of the Sanitary Hot Water (SHW) application (usually from 10 °C to 60 °C with COPs up to 6). This paper presents a model to find the optimal size of a system (heat pump and recovery heat exchanger) based on water sources to produce SHW compared to the conventional production with a gas boiler in order to maximize the benefit. The model includes a thermal and economic analysis for a base case and analyzes the influence of a wide set of parameters which could have a significant influence. Even the uncertainties involved, results point out considerable benefits from this substitution based on the capacity of the system. Thus, demonstrating the importance of the optimal size analysis before an investment is done.Part of the work presented was carried by Estefania Hervas Blasco with the financial support of a PhD scholarship from the Spanish government SFPI1500X074478XV0. Part of the work presented was carried by Miguel Pitarch-Mocholi with the financial support of a PhD scholarship from the Universitat Politecnica de Valencia. The authors would like also to acknowledge the Spanish 'MINISTERIO DE ECONOMIA Y COMPETITIVIDAD', through the project ref-ENE2014-53311-C2-1-P-AR "Aprovechamiento del calor residual a baja temperatura mediante bombas de calor para la produccion de agua caliente" for the given supportHervas-Blasco, E.; Pitarch, M.; Navarro-Peris, E.; Corberán, JM. (2017). Optimal sizing of a heat pump booster for sanitary hot water production to maximize benefit for the substitution of gas boilers. Energy. 127:558-570. https://doi.org/10.1016/j.energy.2017.03.13155857012
Growth and texture of Spark Plasma Sintered Al2O3 ceramics: a combined analysis of X-rays and Electron Back Scatter Diffraction
Textured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of
undoped commercial a-Al2O3 powders. Various parameters (density, grain growth,
grain size distribution) of the alumina ceramics, sintered at two typical
temperatures 1400{\deg}C and 1700{\deg}C, are investigated. Quantitative
textural and structural analysis, carried out using a combination of Electron
Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented
in the form of mapping, and pole figures. The mechanical properties of these
textured alumina ceramics include high elastic modulus and hardness value with
high anisotropic nature, opening the door for a large range of applicationsComment: 16 pages, 6 figures, submitted to J. Appl. Phy
Potential fuel saving in a powertrain derived from the recovery of the main energy losses for a long haul European mission
[EN] The reduction of automotive fuel consumption and emissions remains one of the main challenges. This paper presents the potential fuel saving in a CNG-powertrain derived from the recovery of the main energy losses. The analysis includes the kinetic energy recovery by a belt starter generator (BSG), the exhaust gas waste heat recuperation by using in a cascade approach, a thermoelectric generator (TEG) and a turbo-generator (TBG)- and the electrification of the main auxiliaries. An additional 48 V board net as well as the addition of a storage system are also included in the study. To support on the design phase of the project and in the operation strategy, a dynamic model in Matlab/Simulink (R) has been used. The model includes all the new components/major changes required in the vehicle- experimentally validated-. It has been used on backward simulations for the ACEA long haul mission in order to maximize the vehicle's efficiency.
Estimations at rating point (600 Nm and 1200 rpm) result in an electric production up to 4 kW h and a fuel saving of 7.5%. The most convenient technologies in the ACEA cycle turns out to be the KERs followed by the TBG.This work has been developed in the frame of the project of the European Seventh Union Framework Program by the project High efficiency energy conversion for future heavy duty transport High efficiency energy conversion for future heavy duty transport GASTone grant agreement 605456. The authors are grateful for the given support.Hervas-Blasco, E.; Navarro-Peris, E.; De Rosa, M.; Corberán, JM. (2017). Potential fuel saving in a powertrain derived from the recovery of the main energy losses for a long haul European mission. Energy Conversion and Management. 150:485-499. https://doi.org/10.1016/j.enconman.2017.08.01848549915
Energy optimization of a thermal storage tank for Domestic Hot Water production
[EN] According to the European Commission, the residential sector is responsible at this moment of the 40 % of the energy consumption and 36 % of the associated CO2 emissions in Europe. Regarding the water heating consumption, it is currently responsible for 14.5 % energy consumption of the average European dwelling. This percentage is expected to increase drastically within the concept of Near Zero Energy Building (NZEB) since the associated heating consumption percentage will be decreased largely. In this way, the energy consumption associated for water heating should be reduced, and it only can be done by using highly energy efficient technologies, such as heat pump (HP), and decreasing the energy losses associated to the facilities.
In the frame of the European Project NEXTHPG of the 7th framework program, a new prototype of heat pump booster for the production of domestic hot water was developed. The developed prototype uses an innovative subcooling control system, which allows increasing the COP of the system in more than 30% compared to conventional subcritical heat pump systems. Nevertheless, in a real installation apart from the heat pump there are other factors contributing to the final energy consumption of the whole system like system configuration, control algorithm, tank size and the like. Therefore, an estimation of the final energy consumption of the system could be significantly different from the obtained taking into account only the pump performance.
The present work is focused on the development of a model in order to optimize the design of the whole system using the prototype of the NEXTHPG project in order to satisfy the domestic hot water demand of a building for 20 people. The integrated system model will include the heat pump, the water tank, a heat exchanger in order to recover part of the waste heat (such as the heat coming from the sewage water in the domestic sector or from condensing loops in tertiary sector) and a random generator of domestic hot water demand profile.
From the results of this work, the proper sizing of the heat pump and the water tank, as well as the control algorithm, are obtained and the potential annual energy consumption of this type of system is estimated.Part of the work presented was carried by Estefanía Hervás Blasco with the financial support of
a PhD scholarship from the Spanish government SFPI1500 x 074478XV0. The authors would
like also to acknowledge the Spanish MINISTERIO DE ECONOMIA Y COMPETITIVIDAD¿,
thorugh the project. MAXIMIZACION DE LA EFICIENCIA Y MINIMIZACION DEL
IMPACTO AMBIENTAL DE BOMBAS DE CALOR PARA LA DESCARBONIZACION DE
LA CALEFACCION/ACS EN LOS EDIFICIOS DE CONSUMO CASI NULO with the
reference ENE2017-83665-C2-1-P for the given support and REDUCCIÓN DE LAS
EMISIONES DE CO2 EN LA PRODUCCIÓN DE AGUA CALIENTE A ALTA
TEMPERATURA A PARTIR DE LA RECUPERACIÓN DE CALOR RESIDUAL MEDIANTE
EL USO DE UNA BOMBA DE CALOR with the reference SP20180039.Masip, X.; Álvarez-Piñeiro, L.; Hervas-Blasco, E.; Navarro-Peris, E.; Corberán, JM. (2019). Energy optimization of a thermal storage tank for Domestic Hot Water production. Universidad de Castilla-La Mancha
José Antonio Almendros Ibáñez. 167-175. http://hdl.handle.net/10251/180696S16717
Measurements of W H and ZH production in the H → bb¯ decay channel in pp collisions at 13 TeV with the ATLAS detector
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA
The Presampler for the Forward and Rear Calorimeter in the ZEUS Detector
The ZEUS detector at HERA has been supplemented with a presampler detector in
front of the forward and rear calorimeters. It consists of a segmented
scintillator array read out with wavelength-shifting fibers. We discuss its
desi gn, construction and performance. Test beam data obtained with a prototype
presampler and the ZEUS prototype calorimeter demonstrate the main function of
this detector, i.e. the correction for the energy lost by an electron
interacting in inactive material in front of the calorimeter.Comment: 20 pages including 16 figure
Traumatic brain injury leads to alterations in contusional cortical miRNAs involved in dementia
There is compelling evidence that head injury is a significant environmental risk factor for Alzheimer's disease (AD) and that a history of traumatic brain injury (TBI) accelerates the onset of AD. Amyloid-β plaques and tau aggregates have been observed in the post-mortem brains of TBI patients; however, the mechanisms leading to AD neuropathology in TBI are still unknown. In this study, we hypothesized that focal TBI induces changes in miRNA expression in and around affected areas, resulting in the altered expression of genes involved in neurodegeneration and AD pathology. For this purpose, we performed a miRNA array in extracts from rats subjected to experimental TBI, using the controlled cortical impact (CCI) model. In and around the contusion, we observed alterations of miRNAs associated with dementia/AD, compared to the contralateral side. Specifically, the expression of miR-9 was significantly upregulated, while miR-29b, miR-34a, miR-106b, miR-181a and miR-107 were downregulated. Via qPCR, we confirmed these results in an additional group of injured rats when compared to naïve animals. Interestingly, the changes in those miRNAs were concomitant with alterations in the gene expression of mRNAs involved in amyloid generation and tau pathology, such as β-APP cleaving enzyme (BACE1) and Glycogen synthase-3-β (GSK3β). In addition increased levels of neuroinflammatory markers (TNF-α), glial activation, neuronal loss, and tau phosphorylation were observed in pericontusional areas. Therefore, our results suggest that the secondary injury cascade in TBI affects miRNAs regulating the expression of genes involved in AD dementia
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