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排序方式: 共有4134条查询结果,搜索用时 31 毫秒
1.
Lucía Beltrn-Camacho Marta Rojas-Torres M
Carmen Durn-Ruiz 《International journal of molecular sciences》2021,22(5)
Critical limb ischemia (CLI) constitutes the most severe form of peripheral arterial disease (PAD), it is characterized by progressive blockade of arterial vessels, commonly correlated to atherosclerosis. Currently, revascularization strategies (bypass grafting, angioplasty) remain the first option for CLI patients, although less than 45% of them are eligible for surgical intervention mainly due to associated comorbidities. Moreover, patients usually require amputation in the short-term. Angiogenic cell therapy has arisen as a promising alternative for these “no-option” patients, with many studies demonstrating the potential of stem cells to enhance revascularization by promoting vessel formation and blood flow recovery in ischemic tissues. Herein, we provide an overview of studies focused on the use of angiogenic cell therapies in CLI in the last years, from approaches testing different cell types in animal/pre-clinical models of CLI, to the clinical trials currently under evaluation. Furthermore, recent alternatives related to stem cell therapies such as the use of secretomes, exosomes, or even microRNA, will be also described. 相似文献
2.
Antoine Depoorter Carmen Kalalian Corinne Emmelin Chantal Lorentz Christian George 《Indoor air》2021,31(3):682-692
People spend approximately 80% of their time indoor, making the understanding of the indoor chemistry an important task for safety. The high surface-area-to-volume ratio characteristic of indoor environments leads the semi-volatile organic compounds (sVOCs) to deposit on the surfaces. Using a long path absorption photometer (LOPAP), this work investigates the formation of nitrous acid (HONO) through the photochemistry of adsorbed nitrate anions and its enhancement by the presence of furfural. Using a high-resolution proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS), this work also investigates the surface emissions of VOCs from irradiated films of furfural and a mix of furfural and nitrate anions. Among the emitted VOCs, 2(5H)-furanone/2-Butenedial was observed at high concentrations, leading to maleic anhydride formation after UV irradiation. Moreover, the addition of potassium nitrate to the film formed NOx and HONO concentrations up to 10 ppb, which scales to ca. 4 ppb for realistic indoor conditions. This work helps to understand the high levels of HONO and NOx measured indoors. 相似文献
3.
Juana Maria de Lourdes Medina-Contreras Patrick Mailloux-Salinas Juventino III Colado-Velazquez Norma Leticia Gomez Viquez Gómez-Viquez Rodrigo Velázquez-Espejel Ana del Carmen Susunaga-Notario David Julian Arias-Chávez Guadalupe Bravo 《Journal of the science of food and agriculture》2020,100(7):3212-3219
4.
Varani L. Reggiani L. Kuhn T. Gonzalez T. Pardo D. 《Electron Devices, IEEE Transactions on》1994,41(11):1916-1925
We present a microscopic interpretation of electronic noise in semiconductor materials and two-terminal devices. The theory is based on Monte Carlo simulations of the carrier motion self-consistently coupled with a Poisson solver. Current and voltage noise operations are applied and their respective representations discussed. As application we consider the cases of homogeneous materials, resistors, n+nn + structures, and Schottky-barrier diodes. Phenomena associated with coupling between fluctuations in carrier velocity and self-consistent electric field are quantitatively investigated for the first time. At increasing applied fields hot-carrier effects are found to be of relevant importance in all the cases considered here. As a general result, noise spectroscopy is found to be a source of valuable information to investigate and characterize transport properties of semiconductor materials and devices 相似文献
5.
This paper looks at the concepts of entities, identities, identifiers and credentials, their definitions, and how they combine
to authenticate an identity to an account, or function, within a service. Credentials can be divided into several different
types on the basis of their use, origin and characteristics. In particular, types such as composite, dynamic and derived credentials
will be considered, and their applicability within an identity management system. Each credential must be managed through
its entire life cycle from initial registration, general use and suspension, to deletion. The notion of public (i.e. freely
distributable) and private (i.e. known only to you) aspects of a credential is explored. The bindings, by trusted third parties,
of identifiers and public credentials into permits and instruments of proof is explained along with the convenience, but greater
exposure, of local information. Several scenarios are analysed in terms of how different types of credentials are employed
during the authentication process. 相似文献
6.
O Bernard B Chachuat A Hélias B Le Dantec B Sialve J-P Steyer L Lardon P Neveu S Lambert J Gallop M Dixon P Ratini A Quintabà S Frattesi J M Lema E Roca G Ruiz J Rodriguez A Franco P Vanrolleghem U Zaher D J W De Pauw K De Neve K Lievens D Dochaine O Schoefs H Fibrianto R Farina V Alcaraz Gonzalez V Gonzalez Alvarez P Lemaire J A Martinez F Esandi O Duclaud J F Lavigne 《Water science and technology》2005,52(1-2):457-464
The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem. 相似文献
7.
Penedo Frank J.; Dahn Jason R.; Gonzalez Jeffrey S.; Molton Ivan; Carver Charles S.; Antoni Michael H.; Roos Bernard A.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2003,22(2):220
This study evaluated relations among optimism, perceived stress management skills (PSMS), and positive mood in 46 men who had surgical treatment for localized prostate cancer. The authors found that optimism, PSMS, and positive mood scores were positively correlated. Positive mood was unrelated to demographic and disease-related control variables. In a hierarchical regression model controlling for PSMS, the relationship between optimism and positive mood became nonsignificant, whereas PSMS remained a correlate of positive mood. Results suggest that the relationship between optimism and positive mood may be mediated by belief in being able to use stress management techniques effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Javier Roca-Pardiñas Carmen Cadarso-Suárez María J. Lado 《Computational statistics & data analysis》2008,52(4):1958-1970
In many applications, the joint effect of two continuous covariates on the target binary response may vary across groups defined by levels of a given factor. A testing procedure that would enable this type of surface-by-factor interactions to be detected has been designed. To accomplish this goal, a logistic generalized additive model (GAM) with bivariate continuous interactions varying across groups defined by levels of a factor is considered. A local scoring algorithm based on local linear kernel smoothers was implemented to estimate the proposed logistic GAM. Bootstrap resampling techniques were used for the purpose of testing for factor-by-surface interactions. Given the high computational cost involved, binning techniques were used to speed up computation in the estimation and testing processes. The adequacy of the bootstrap-based test was assessed by means of a simulation study. If a factor-by-surface interaction is detected in the model, it is then established that the use of the odds-ratio curves is very useful in obtaining a direct interpretation of the fitted model. The benefits of using this methodology when analyzing real data are illustrated by applying the technique to the outputs produced by a computerized system dedicated to the early detection of breast cancer. 相似文献
9.
10.
Gonzalez A. Valero-Garcia M. Diaz de Cerio L. 《Parallel and Distributed Systems, IEEE Transactions on》1995,6(8):803-814
Many parallel algorithms use hypercubes as the communication topology among their processes. When such algorithms are executed on hypercube multicomputers the communication cost is kept minimum since processes can be allocated to processors in such a way that only communication between neighbor processors is required. However, the scalability of hypercube multicomputers is constrained by the fact that the interconnection cost-per-node increases with the total number of nodes. From scalability point of view, meshes and toruses are more interesting classes of interconnection topologies. This paper focuses on the execution of algorithms with hypercube communication topology on multicomputers with mesh or torus interconnection topologies. The proposed approach is based on looking at different embeddings of hypercube graphs onto mesh or torus graphs. The paper concentrates on toruses since an already known embedding, which is called standard embedding, is optimal for meshes. In this paper, an embedding of hypercubes onto toruses of any given dimension is proposed. This novel embedding is called xor embedding. The paper presents a set of performance figures for both the standard and the xor embeddings and shows that the latter outperforms the former for any torus. In addition, it is proven that for a one-dimensional torus (a ring) the xor embedding is optimal in the sense that it minimizes the execution time of a class of parallel algorithms with hypercube topology. This class of algorithms is frequently found in real applications, such as FFT and some class of sorting algorithms 相似文献