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31.
A Gregorio Vila ML Pedro-Botet Montoya N Sopena Galindo L Matas Andreu M Sabria Leal 《Canadian Metallurgical Quarterly》1996,13(2):97-98
After more than a decade of special treatment, HIV medicine is ready to enter the mainstream of medical practice in developed countries. Access to a conveniently located, well informed, primary care doctor who works well with an appropriate specialist is the cornerstone of best medical care for chronic illness, including HIV disease. Managing HIV is part of the second phase of a national educational program aimed at equipping more doctors with the skills to care for people with HIV. 相似文献
32.
Small-angle x-ray solution scattering (SAXS) is analyzed with a new method to retrieve convergent model structures that fit the scattering profiles. An arbitrary hexagonal packing of several hundred beads containing the problem object is defined. Instead of attempting to compute the Debye formula for all of the possible mass distributions, a genetic algorithm is employed that efficiently searches the configurational space and evolves best-fit bead models. Models from different runs of the algorithm have similar or identical structures. The modeling resolution is increased by reducing the bead radius together with the search space in successive cycles of refinement. The method has been tested with protein SAXS (0.001 < S < 0.06 A(-1)) calculated from x-ray crystal structures, adding noise to the profiles. The models obtained closely approach the volumes and radii of gyration of the known structures, and faithfully reproduce the dimensions and shape of each of them. This includes finding the active site cavity of lysozyme, the bilobed structure of gamma-crystallin, two domains connected by a stalk in betab2-crystallin, and the horseshoe shape of pancreatic ribonuclease inhibitor. The low-resolution solution structure of lysozyme has been directly modeled from its experimental SAXS profile (0.003 < S < 0.03 A(-1)). The model describes lysozyme size and shape to the resolution of the measurement. The method may be applied to other proteins, to the analysis of domain movements, to the comparison of solution and crystal structures, as well as to large macromolecular assemblies. 相似文献
33.
Experimental simian varicella virus (SVV) infection of St. Kitts vervet monkeys was evaluated as an animal model to investigate human varicella-zoster virus (VZV) infections. During the incubation period, viremia disseminated infectious virus throughout the body via infected peripheral blood lymphocytes (PBLs). A vesicular skin rash in the inguinal area, and on the abdomen, extremities, and face appeared on day 7-10 postinfection. Necrosis and hemorrhage in lung and liver tissues from acutely infected monkeys were evident upon histologic analysis. Recovery from simian varicella was accompanied by a rise in the serum neutralizing antibody response to the virus. SVV latency was established in trigeminal ganglia of monkeys which resolved the acute infection. This study indicates that experimental SVV infection of St. Kitts vervets is a useful animal model to investigate SVV and VZV pathogenesis and to evaluate potential antiviral agents and vaccines. 相似文献
34.
J Calvo JM Vildà L Places M Simarro O Padilla D Andreu KS Campbell C Aussel F Lozano 《Canadian Metallurgical Quarterly》1998,161(11):6022-6029
CD5 is a lymphocyte surface glycoprotein with a long cytoplasmic domain suitable for phosphorylation and signal transduction, which is involved in the modulation of Ag-specific receptor-mediated activation and differentiation signals. In this study, we use Jurkat T cell transfectants of CD5 cytoplasmic tail mutants to reveal phosphorylation sites relevant to signal transduction. Our results show that casein kinase II (CKII) is responsible for the constitutive phosphorylation of CD5 molecules at a cluster of three serine residues located at the extreme C terminus (S458, S459, and S461). Furthermore, the yeast two-hybrid system demonstrates the specific association between the C-terminal regions of the CD5 cytoplasmic tail and the regulatory beta subunit of CKII. We demonstrate that CKII associates with and phosphorylates the C-terminal region of CD5, a conserved domain known to be relevant for the generation of second lipid messengers, and thereby enables at least one component of its signaling function. 相似文献
35.
D. Salomoni I. Campos L. Gaido J. Marco de Lucas P. Solagna J. Gomes L. Matyska P. Fuhrman M. Hardt G. Donvito L. Dutka M. Plociennik R. Barbera I. Blanquer A. Ceccanti E. Cetinic M. David C. Duma A. López-García G. Moltó P. Orviz Z. Sustr M. Viljoen F. Aguilar L. Alves M. Antonacci L. A. Antonelli S. Bagnasco A. M. J. J. Bonvin R. Bruno Y. Chen A. Costa D. Davidovic B. Ertl M. Fargetta S. Fiore S. Gallozzi Z. Kurkcuoglu L. Lloret J. Martins A. Nuzzo P. Nassisi C. Palazzo J. Pina E. Sciacca D. Spiga M. Tangaro M. Urbaniak S. Vallero B. Wegh V. Zaccolo F. Zambelli T. Zok 《Journal of Grid Computing》2018,16(3):381-408
This paper describes the achievements of the H2020 project INDIGO-DataCloud. The project has provided e-infrastructures with tools, applications and cloud framework enhancements to manage the demanding requirements of scientific communities, either locally or through enhanced interfaces. The middleware developed allows to federate hybrid resources, to easily write, port and run scientific applications to the cloud. In particular, we have extended existing PaaS (Platform as a Service) solutions, allowing public and private e-infrastructures, including those provided by EGI, EUDAT, and Helix Nebula, to integrate their existing services and make them available through AAI services compliant with GEANT interfederation policies, thus guaranteeing transparency and trust in the provisioning of such services. Our middleware facilitates the execution of applications using containers on Cloud and Grid based infrastructures, as well as on HPC clusters. Our developments are freely downloadable as open source components, and are already being integrated into many scientific applications. 相似文献
36.
Songyang Yuan Yeming Xian Yi Long Andreu Cabot Wenzhe Li Jiandong Fan 《Advanced functional materials》2021,31(51):2106233
Inorganic CsPbIxBr3−x perovskite solar cells (PSCs) have gained enormous interest due to their excellent thermal stabilities. However, their intrinsically poor moisture stability hampers their further development. Herein, a chromium-based metal–organic framework group is intercalated inside the inorganic Pb I framework, resulting in a new multiple-dimensional electronically coupled CsPbI2Br perovskite. In this structurally and electronically coupled perovskite, the π-conjugated terpyridyl can delocalize the excited valence electrons of metal Cr3+ ion, enabling multi-interactive charge-carrier transport channels within CsPbI2Br perovskites. The stability and efficiency of the produced devices are substantially enhanced in comparison to their counterparts with only a pristine CsPbI2Br active layer. The optimized all-inorganic PSC yields a power conversion efficiency (PCE) as high as 17.02%. Remarkably, the stabilized device retains 80% of its PCE after 1000 h in the ambient atmosphere. This study provides a new paradigm toward addressing the stability challenge of the inorganic perovskite while enhancing its carrier transport ability. 相似文献
37.
S. Montserrat G. Andreu P. Corts Y. Calventus P. Colomer J. M. Hutchinson J. Mlek 《应用聚合物科学杂志》1996,61(10):1663-1674
The effect of a reactive diluent (RD) on the kinetics of the curing of an epoxy resin, based on diglycidyl ether of bisphenol A (DGEBA), with a carboxylic anhvdride derived from methyl-tetrahydrophthalic anhydride (MTHPA) catalyzed by a tertiary amine has been studied. The reactive diluent was a low-viscosity aliphatic diglycidyl ether, and the compositions per 100 parts by weight (pbw) of DGEBA were 10, 30, and 50 pbw of RD with the stoichiometric quantity of MTHPA and 1 pbw of catalyst. The curing kinetics was monitored by differential scanning calorimetry (DSC), and the kinetic parameters were determined from the nonisothermal DSC curves by the method described by Málek. The kinetic analysis suggests that the two-parameter autocatalytic model is the more appropriate to describe the kinetics of the curing reaction of this epoxy-anhydride system. The kinetic parameters thus derived satisfactorily simulate both the nonisothermal DSC curves and the isothermal conversion-time plots. Increasing the RD content leads to a small increase in both the nonisothermal and the isothermal heats of curing and has a slight effect on the kinetic parameters E, ln A, m, and n, and, consequently, on the overall reactivity of the system. On the other hand, the increase of the RD content significantly affects the structure of the crosslinked epoxy. It is confirmed that the introduction of aliphatic chains in the structure of the epoxy increases the mobility of the segmental chains in the glass transition region. The consequence of this chemical modification is a decrease of the glass transition temperature, Tg. © 1996 John Wiley & Sons, Inc. 相似文献
38.
Ordeig O Ortiz P Muñoz-Berbel X Demming S Büttgenbach S Fernández-Sánchez C Llobera A 《Analytical chemistry》2012,84(8):3546-3553
A dual lab on a chip (DLOC) approach that enables simultaneous optical and electrochemical detection working in a continuous flow regime is presented. Both detection modes are integrated for the first time into a single detection volume and operate simultaneously with no evidence of cross-talk. The electrochemical cell was characterized amperometrically by measuring the current in ferrocyanide solutions at +0.4 V vs gold pseudoreference electrode, at a flow rate of 200 μL min(-1). The experimental results for ferrocyanide concentrations ranging from 0.005 to 2 mM were in good agreement with the values predicted by the Levich equation for a microelectrode inside a rectangular channel, with a sensitivity of 2.059 ± 0.004 μA mM(-1) and a limit of detection (LoD) of (2.303 ± 0.004) × 10(-3) mM. Besides, optical detection was evaluated by measuring the absorbance of ferricyanide solutions at 420 nm. The results obtained therein coincide with those predicted by the Beer-Lambert law for a range of ferricyanide concentrations from 0.005 to 0.3 mM and showed an estimated LoD of (0.553 ± 0.001) × 10(-3) mM. The DLOC was finally applied to the analysis of L-lactate via a bienzymatic reaction involving lactate oxidase (LOX) and horseradish peroxidase (HRP). Here, the consumption of the reagent of the reaction (ferrocyanide) was continuously monitored by amperometry whereas the product of the reaction (ferricyanide) was recorded by absorbance. The DLOC presented good performance in terms of sensitivity and limit of detection, comparable to other fluidic systems found in the literature. Additionally, the ability to simultaneously quantify enzymatic reagent consumption and product generation confers the DLOC a self-verifying capability which in turn enhances its robustness and reliability. 相似文献
39.
40.
J. Andreu U. Bidarte A. Astarloa I. Martínez de Alegría P. Ibáñez 《International Journal of Electronics》2013,100(11):1181-1200
Matrix Converters (MCs) present several advantages, but yet several barriers must be overcome, such as MC modulation and control technique complexity. This article proposes a multiplatform environment that allows the implementation of the Double Sided Space Vector Modulation (DS-SVM) algorithm in a last-generation Field Programmable Gate Array (FPGA) device. The traditional digital control architecture, based on a SP and some additional devices, is improved by means of a last generation FPGA where the main processor (PowerPC), internal memory, communication interfaces, I/O capabilities and a hardware core that executes the DS-SVM have been connected using on-chip buses. The methodology begins by defining the DS-SVM in a Matlab-Simulink environment. The PowerPC delivers 680 MIPS, but it is not a good candidate to execute the DS-SVM algorithm because it is not possible to achieve the modulation frequency that is necessary for an MC. A new configurable hardware circuit that implements the whole DS-SVM algorithm is proposed. This solution achieves modulation frequencies over 100 kHz. This hardware core is connected to one of the PowerPC buses and the processor can configure it or get feedback information at any time. As the processor is liberated from the very time-consuming DS-SVM computation, it can execute many higher level tasks. 相似文献