875 research outputs found
Pathogenesis and Management of Alcoholic Liver Disease
Alcoholic liver disease (ALD) is a leading cause of liver-related morbidity and mortality. ALD encompasses a spectrum of disorders ranging from asymptomatic steatosis, alcoholic steatohepatitis (ASH), fibrosis, cirrhosis and its related complications. Moreover, patients can develop an acute-on-chronic form of liver failure called alcoholic hepatitis (AH). Most patients are diagnosed at advanced stages of the disease with higher rates of complications and mortality. The mainstream of therapy of ALD patients, regardless of the disease stage, is prolonged alcohol abstinence. The current therapeutic regimens for AH (i.e. prednisolone) have limited efficacy and targeted therapies are urgently needed. The development of such therapies requires translational studies in human samples and suitable animal models that reproduce clinical and histological features of AH. In recent years, new animal models that simulate some of the features of human AH have been developed, and translational studies using human samples have identified potential pathogenic factors and histological parameters that predict survival. In this review, we discuss the pathogenesis and management of ALD, focusing on AH, its current therapies and potential treatment targets
La Europa amplia: Una nueva noción de Europa tras la ampliación de la Unión Europea
La gran prioridad de la Unión Europea (UE) en la última década ha sido la ampliación hacia el Este. Acordada como un objetivo estratégico de primer orden tras la caída del muro de Berlín y como un mecanismo de anclaje de las reformas económicas y políticas de los países de Europa Central, la promesa de la ampliación ha cumplido sus objetivos: hoy los países centroeuropeos han consolidado su democracia y sus economías han experimentado una transformación rápida y profunda que parece hacerlas prestas a afrontar los retos de su integración formal en Europa.
El entendimiento de esta nueva realidad solamente es posible, no obstante, desde la percepción de cómo se están produciendo las ultimas adaptaciones en la Europa Central que a partir del 1 de mayo de 2004 es ya parte de la Unión, así como en la misma Unión, que prepara sus instituciones y políticas para acomodar la presencia de sus nuevos miembros. Ambos aspectos son analizados, respectivamente, en las secciones 2 y 3 de este artículo, en tanto que en la sección 4 se aborda el estudio de la nueva política de vecindad de la UE tras la ampliación. Finalmente, en la sección 5 se extraen las principales conclusiones
Design of a Multimode MIMO Antenna Using the Theory of Characteristic Modes
In this communication, the design procedure of a multimode Multiple-Input Multiple-Output (MIMO) antenna is presented. The antenna consists of a metallic ring antenna operating with different orthogonal modes, whose performance in a MIMO system is similar to traditional antenna arrays. Thus, a compact MIMO antenna is obtained, which is very suitable for mobile terminals. A modal analysis of the antenna is carried out first by means of the Theory of Characteristic Modes, in order to identify the different radiating modes of the antenna. Then a set of feeding configurations is proposed so as to excite these modes. As the modes must operate in the same frequency band, a loading technique is used in the antenna in order to shift the resonance frequency of the modes to the proper band
Impact of thermodiffusion on the initial vertical distribution of species in hydrocarbon reservoirs
The Role of Sphingolipids Metabolism in Cancer Drug Resistance
Acid ceramidase (AC); Glucosylceramide synthase (GCS); ShingolipidsCeramidasa ácida (AC); Glucosilceramida sintasa (GCS); EsfingolípidosCeramidasa àcida (AC); Glucosilceramida sintasa (GCS); EsfingolípidsDrug resistance continues to be one of the major challenges to cure cancer. As research in this field evolves, it has been proposed that numerous bioactive molecules might be involved in the resistance of cancer cells to certain chemotherapeutics. One well-known group of lipids that play a major role in drug resistance are the sphingolipids. Sphingolipids are essential components of the lipid raft domains of the plasma membrane and this structural function is important for apoptosis and/or cell proliferation. Dysregulation of sphingolipids, including ceramide, sphingomyelin or sphingosine 1-phosphate, has been linked to drug resistance in different types of cancer, including breast, melanoma or colon cancer. Sphingolipid metabolism is complex, involving several lipid catabolism with the participation of key enzymes such as glucosylceramide synthase (GCS) and sphingosine kinase 1 (SPHK1). With an overview of the latest available data on this topic and its implications in cancer therapy, this review focuses on the main enzymes implicated in sphingolipids metabolism and their intermediate metabolites involved in cancer drug resistance.We thank Teresa Moline and Rosa Somoza from the VHIR. This work was supported by grants from the Instituto de Salud Carlos III (ISCIII; PI20/00556 and CP03/00101 [ML]) and CIBERONC (ML). This work was also co-financed by the European Regional Fund (ERDF) and AECC (Spanish Association of Cancer Research) (Founding Ref. GC16173720CARR [ML]). YG-M, CM, and AS-G were supported by the VHIR, iP-FIS (ISCIII) and VHIR fellowships, respectively
Effect of the Front and Back Illumination on Sub-Terahertz Detection Using n-Channel Strained-Silicon MODFETs
[EN] Plasma waves in semiconductor gated 2-D systems can be used to efficiently detect Terahertz (THz) electromagnetic radiation. This work reports on the response of a strained-Si Modulation-doped Field-Effect Transistor (MODFET) under front and back sub-THz illumination. The response of the MODFET has been characterized using a two-tones solid-state continuous wave source at 0.15 and 0.30 THz. The DC drain-to-source voltage of 500-nm gate length transistors transducing the sub-THz radiation (photovoltaic mode) exhibited a non-resonant response in agreement with literature results. Two configurations of the illumination were investigated: (i) front side illumination in which the transistor was shined on its top side, and (ii) back illumination side where the device received the sub-THz radiation on its bottom side, i.e., on the Si substrate. Under excitation at 0.15 THz clear evidence of the coupling of terahertz radiation by the bonding wires was found, this coupling leads to a stronger response under front illumination than under back illumination. When the radiation is shifted to 0.3 THz, as a result of a lesser efficient coupling of the EM radiation through the bonding wires, the response under front illumination was considerably weakened while it was strengthened under back illumination. Electromagnetic simulations explained this behavior as the magnitude of the induced electric field in the channel of the MODFET was considerably stronger under back illumination.This research was funded by the Ministerio de Ciencia, Investigacion y Universidades of Spain andFEDER (ERDF: European Regional Development Fund) under the Research Grants numbers RTI2018-097180-B-100 and TEC2016-78028-C3-3-P and FEDER/Junta de Castilla y Leon Research Grant number SA256P18. Also by Conselleria d'Educacio, lnvestigacio, Cultura i Esport, Generalitat Valenciana (Spain) through the grant AIC0/2019/018. The APC received no external funding.Delgado-Notario, JA.; Calvo-Gallego, J.; Velázquez-Pérez, JE.; Ferrando Bataller, M.; Fobelets, K.; Meziani, YM. (2020). Effect of the Front and Back Illumination on Sub-Terahertz Detection Using n-Channel Strained-Silicon MODFETs. Applied Sciences. 10(17):1-9. https://doi.org/10.3390/app10175959S191017Lewis, R. A. (2019). A review of terahertz detectors. Journal of Physics D: Applied Physics, 52(43), 433001. doi:10.1088/1361-6463/ab31d5Dragoman, D., & Dragoman, M. (2004). Terahertz fields and applications. Progress in Quantum Electronics, 28(1), 1-66. doi:10.1016/s0079-6727(03)00058-2Mittleman, D. M. (2017). Perspective: Terahertz science and technology. Journal of Applied Physics, 122(23), 230901. doi:10.1063/1.5007683Pawar, A. Y., Sonawane, D. D., Erande, K. B., & Derle, D. V. (2013). Terahertz technology and its applications. Drug Invention Today, 5(2), 157-163. doi:10.1016/j.dit.2013.03.009Federici, J., & Moeller, L. (2010). Review of terahertz and subterahertz wireless communications. Journal of Applied Physics, 107(11), 111101. doi:10.1063/1.3386413Federici, J. F., Schulkin, B., Huang, F., Gary, D., Barat, R., Oliveira, F., & Zimdars, D. (2005). THz imaging and sensing for security applications—explosives, weapons and drugs. Semiconductor Science and Technology, 20(7), S266-S280. doi:10.1088/0268-1242/20/7/018Dyakonov, M., & Shur, M. (1993). Shallow water analogy for a ballistic field effect transistor: New mechanism of plasma wave generation by dc current. Physical Review Letters, 71(15), 2465-2468. doi:10.1103/physrevlett.71.2465Dyakonov, M., & Shur, M. (1996). Detection, mixing, and frequency multiplication of terahertz radiation by two-dimensional electronic fluid. IEEE Transactions on Electron Devices, 43(3), 380-387. doi:10.1109/16.485650Tauk, R., Teppe, F., Boubanga, S., Coquillat, D., Knap, W., Meziani, Y. M., … Shur, M. S. (2006). Plasma wave detection of terahertz radiation by silicon field effects transistors: Responsivity and noise equivalent power. Applied Physics Letters, 89(25), 253511. doi:10.1063/1.2410215Rumyantsev, S. L., Fobelets, K., Veksler, D., Hackbarth, T., & Shur, M. S. (2008). Strained-Si modulation doped field effect transistors as detectors of terahertz and sub-terahertz radiation. Semiconductor Science and Technology, 23(10), 105001. doi:10.1088/0268-1242/23/10/105001Javadi, E., Delgado-Notario, J. A., Masoumi, N., Shahabadi, M., Velázquez-Pérez, J. E., & Meziani, Y. M. (2018). Continuous Wave Terahertz Sensing Using GaN HEMTs. physica status solidi (a), 215(11), 1700607. doi:10.1002/pssa.201700607Delgado-Notario, J. A., Clericò, V., Diez, E., Velázquez-Pérez, J. E., Taniguchi, T., Watanabe, K., … Meziani, Y. M. (2020). Asymmetric dual-grating gates graphene FET for detection of terahertz radiations. APL Photonics, 5(6), 066102. doi:10.1063/5.0007249Lewis, R. A. (2014). A review of terahertz sources. Journal of Physics D: Applied Physics, 47(37), 374001. doi:10.1088/0022-3727/47/37/374001Delgado-Notario, J., Velazquez-Perez, J., Meziani, Y., & Fobelets, K. (2018). Sub-THz Imaging Using Non-Resonant HEMT Detectors. Sensors, 18(2), 543. doi:10.3390/s18020543Gaspari, V., Fobelets, K., Velazquez-Perez, J. E., Ferguson, R., Michelakis, K., Despotopoulos, S., & Papavassilliou, C. (2004). Effect of temperature on the transfer characteristic of a 0.5 μm-gate Si:SiGe depletion-mode n-MODFET. Applied Surface Science, 224(1-4), 390-393. doi:10.1016/j.apsusc.2003.08.066Fobelets, K., Jeamsaksiri, W., Papavasilliou, C., Vilches, T., Gaspari, V., Velazquez-Perez, J. E., … König, U. (2004). Comparison of sub-micron Si:SiGe heterojunction nFETs to Si nMOSFET in present-day technologies. Solid-State Electronics, 48(8), 1401-1406. doi:10.1016/j.sse.2004.01.017Delgado Notario, J. A., Javadi, E., Calvo-Gallego, J., Diez, E., Velázquez, J. E., Meziani, Y. M., & Fobelets, K. (2016). Sub-Micron Gate Length Field Effect Transistors as Broad Band Detectors of Terahertz Radiation. International Journal of High Speed Electronics and Systems, 25(03n04), 1640020. doi:10.1142/s0129156416400206Sakowicz, M., Łusakowski, J., Karpierz, K., Grynberg, M., Gwarek, W., Boubanga, S., … Studart, N. (2010). A High Mobility Field-Effect Transistor as an Antenna for sub-THz Radiation. doi:10.1063/1.3295528Knap, W., Teppe, F., Meziani, Y., Dyakonova, N., Lusakowski, J., Boeuf, F., … Shur, M. S. (2004). Plasma wave detection of sub-terahertz and terahertz radiation by silicon field-effect transistors. Applied Physics Letters, 85(4), 675-677. doi:10.1063/1.177503
Thermodiffusion of the tetrahydronaphthalene and dodecane mixture under high pressure and in porous medium
A thermodiffusion cell is used in order to perform Soret experiments on binary mixtures at high pressure and in the presence of a porous medium. The cell is validated at atmospheric pressure with toluene/hexane and the tetrahydronaphthalene/dodecane mixtures. The mass separation follows a diffusive behaviour when the cell is filled with a porous medium. At least three times the relaxation time is needed to have a good estimation of the Soret coefficients. From the transient state of the mass separation and using accepted values of the diffusion coefficient, the tortuosity of the porous medium was evaluated, too. Finally, experiments at high pressure were performed with the tetrahydronaphthalene/dodecane system. In these experiments, decreases of the Soret coefficient and of the tortuosity of the porous medium were measured as a function of the pressure
Comparative Analysis of Bioethanol Production from Different Potential Biomass Sources in the Philippines
To pursue the continuous implementation of the bioethanol blending mandate by the Philippine Biofuels Law, part of the roadmap of the National Biofuels Board (NBB) through the Department of Energy (DOE) is to find a sustainable feedstock. This is due to the deficit in locally produced bioethanol as there is an insufficient supply of currently used feedstock, sugarcane. There are several biomasses available in the country with components viable for ethanol fermentation. Aside from sugarcane, these include sweet sorghum and cassava (first-generation), rice straw and corn stover (second-generation), and macroalgae (third-generation). Among which, sweet sorghum can be considered as the best complementary feedstock to sugarcane as its syrup can be directly fermented to produce bioethanol. Considering its maximum bioethanol potential yield of 100 L/ton for two croppings annually, a comparably low production cost of PhP 36.00/L bioethanol was estimated, competitive enough with the PhP33.43/L bioethanol from sugarcane. Aside from finding a promising feedstock, the bioethanol production volume in the country must be increased to meet the demand through either working on the optimum processing conditions to increase the capacity utilization from the current 77.9% or through installation of additional distilleries
Longitudinally extensive transverse myelitis with AQP4 antibodies revealing ovarian teratoma.
Paraneoplastic myelitis is a rare inflammatory disorder most frequently associated with solid tumors or lymphoproliferative disorders. Patients often harbor onconeuronal antibodies and their prognosis is usually poor. Here we report a 42-year old woman with longitudinally extensive transverse myelitis and aquaporin-4 (AQP4) antibodies that led to the diagnosis of ovarian teratoma. After tumor removal and immune therapy (including corticosteroids, plasma exchange, intravenous immunoglobulins and rituximab) the patient progressively improved achieving complete recovery. Histological study of the teratoma demonstrated neural tissue containing AQP4 expressing cells and intense inflammatory infiltrates, providing evidence for a possible paraneoplastic link between both disorders
Marikina flood hazard models using historical data of water level
In this paper, ten-year historical data of water levels recorded at Sto. Niño, Marikina station of MMDA-EFCOS were analysed and processed to determine the number of times per year (annual frequency) that critical levels of the Marikina River near the Sto. Niño station were reached and for how long (duration). Probability distributions for the annual frequency and duration were then fitted to the samples obtained. Monte Carlo simulation was applied in order to generate possible realizations of the random variables. Summary statistics were then obtained from the simulated values. Finally, backtesting using historical data of water levels after the period of model development was performed to check the validity of the models. The results showed that the models obtained were reliable. The results of this study may be used to guide the local government of Marikina in planning the needed resources in order to sufficiently respond in times of flooding incidents
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