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排序方式: 共有2693条查询结果,搜索用时 16 毫秒
51.
Ornella Rondinone Alessio Murgia Jole Costanza Silvia Tabano Margherita Camanni Luigi Corsaro Laura Fontana Patrizia Colapietro Luciano Calzari Silvia Motta Carlo Santaniello Tatjana Radaelli Enrico Ferrazzi Silvano Bosari Davide Gentilini Silvia Maria Sirchia Monica Miozzo 《International journal of molecular sciences》2022,23(10)
52.
A. Andreone F. Fontana M. Iavarone M. Salluzzo R. Vaglio 《Journal of Low Temperature Physics》1997,107(5-6):527-532
High quality c-axis oriented films of the intriguing intermetallic superconducting compound YNi2B2C have been obtained “in situ” by magnetron sputtering on MgO substrates held at about 800°C. The films showed maximum Tc=15.3 K, †Tc≈0.1 K, room temperature resistivity ρ≈50μΩ·cm, critical current Jc≈105 A/cm2 and Bc2≈6 T. Superconducting films were also obtained on Al2O3 and LaAlO3 single-crystal substrates. From the ρ(T) dependence a value of the Debye temperature Θ
D
=330±20 K can be deduced. At low temperatures the resistivity follows a quadratic power law possibly indicative of a high
value of the electron-phonon interaction parameter λ. In order to clarify the role of λ in these compounds, point contact
spectroscopy measurements have been performed on YNi2B2C and HoNi2B2C bulk samples prepared by inductive melting using a Low Temperature Scanning Tunneling Microscope (LTSTM). In the point contact
regime clear evidence of a superconducting gap have been found in both compounds, corresponding to a moderate strong coupling
behaviour (2†/KTc≈3.8). 相似文献
53.
Alberto Pla-Lpez Raquel Castillo Rocío Cejudo-Marín Olaya García-Pedrero Mariam Bakir-Laso Eva Falomir Miguel Carda 《International journal of molecular sciences》2022,23(13)
Twenty-six triazole-based derivatives were designed for targeting both PD-L1 (programmed death receptor ligand 1) and VEGFR-2 (vascular endothelial growth factor receptor 2). These compounds were synthetized and biologically evaluated as multitarget inhibitors of VEGFR-2, PD-L1 and c-Myc proteins. The antiproliferative activity of these molecules on several tumor cell lines (HT-29, A-549, and MCF-7) and on the non-tumor cell line HEK-293 was determined. The effects on the abovementioned biological targets were evaluated for some selected compounds. Compound 23, bearing a p-chlorophenyl group, showed better results than sorafenib in regard to the downregulation of VEGFR-2 and a similar effect to BMS-8 on both PD-L1 and c-Myc proteins. The antiangiogenic and antivascular activities of chloro derivatives were also established by endothelial microtube formation assay on Matrigel®. 相似文献
54.
55.
Lucas Taoro-Gonzlez Daniel Pereda Catalina Valds-Baizabal Miriam Gonzlez-Gmez Jos A. Prez Ftima Mesa-Herrera Ana Canerina-Amaro Herminia Prez-Gonzlez Covadonga Rodríguez Mario Díaz Raquel Marin 《International journal of molecular sciences》2022,23(13)
Long-chain polyunsaturated fatty acids (LCPUFA), essential molecules whose precursors must be dietary supplied, are highly represented in the brain contributing to numerous neuronal processes. Recent findings have demonstrated that LCPUFA are represented in lipid raft microstructures, where they favor molecular interactions of signaling complexes underlying neuronal functionality. During aging, the brain lipid composition changes affecting the lipid rafts’ integrity and protein signaling, which may induce memory detriment. We investigated the effect of a n-3 LCPUFA-enriched diet on the cognitive function of 6- and 15-months-old female mice. Likewise, we explored the impact of dietary n-3 LCPUFAs on hippocampal lipid rafts, and their potential correlation with aging-induced neuroinflammation. Our results demonstrate that n-3 LCPUFA supplementation improves spatial and recognition memory and restores the expression of glutamate and estrogen receptors in the hippocampal lipid rafts of aged mice to similar profiles than young ones. Additionally, the n-3 LCPUFA-enriched diet stabilized the lipid composition of the old mice’s hippocampal lipid rafts to the levels of young ones and reduced the aged-induced neuroinflammatory markers. Hence, we propose that n-3 LCPUFA supplementation leads to beneficial cognitive performance by “rejuvenating” the lipid raft microenvironment that stabilizes the integrity and interactions of memory protein players embedded in these microdomains. 相似文献
56.
Carlos Casas-Arozamena Alexandra Cortegoso Raquel Pieiro-Perez Alicia Abalo Efigenia Arias Victoria Sampayo Ana Vilar Marta Bouso Eva Diaz Gema Moreno-Bueno Rafael Lpez-Lpez Laura Muinelo-Romay Miguel Abal Juan Cueva 《International journal of molecular sciences》2022,23(15)
Endometrial cancer (EC) is the 4th most common neoplasm of the female genital tract, with 15–20% of patients being of high risk of recurrence which leads to a significant decrease in patient survival. Current therapeutic options for patients with EC are poor, being the combined therapy of carboplatin and paclitaxel the standard of care, with limited efficacy. Therefore, new therapeutic options and better monitoring tools are needed to improve the management of the disease. In the current case report, we showcase the value of liquid biopsy analyses in a microsatellite instability EC patient with initially good prognosis that however underwent rapid progression disease within 6 months post-surgery; through the study of plasma cfDNA/ctDNA dynamics to assess the tumour evolution during treatment, as well as the study of the uterine aspirate as a valuable sample that captures the intra-tumour heterogeneity that allows a comprehensive genomic profiling of the disease to identify potential therapeutic options. Furthermore, preclinical models were generated at the time of tumour progression to assess the efficacy of the identified targeted therapies. 相似文献
57.
Inclusion dynamics hybrid automata 总被引:2,自引:0,他引:2
Alberto Casagrande Carla Piazza Alberto Policriti Bud Mishra 《Information and Computation》2008,206(12):1394-1424
Hybrid systems are dynamical systems with the ability to describe mixed discrete-continuous evolution of a wide range of systems. Consequently, at first glance, hybrid systems appear powerful but recalcitrant, neither yielding to analysis and reasoning through a purely continuous-time modeling as with systems of differential equations, nor open to inferential processes commonly used for discrete state-transition systems such as finite state automata. A convenient and popular model, called hybrid automata, was introduced to model them and has spurred much interest on its tractability as a tool for inference and model checking in a general setting. Intuitively, a hybrid automaton is simply a “finite-state” automaton with each state augmented by continuous variables, which evolve according to a set of well-defined continuous laws, each specified separately for each state. This article investigates both the notion of hybrid automaton and the model checking problem over such a structure. In particular, it relates first-order theories and analysis results on multivalued maps and reduces the bounded reachability problem for hybrid automata whose continuous laws are expressed by inclusions (x′f(x,t)) to a decidability problem for first-order formulæ over the reals. Furthermore, the paper introduces a class of hybrid automata for which the reachability problem can be decided and shows that the problem of deciding whether a hybrid automaton belongs to this class can be again decided using first-order formulæ over the reals. Despite the fact that the bisimulation quotient for this class of hybrid automata can be infinite, we show that our techniques permit effective model checking for a nontrivial fragment of CTL. 相似文献
58.
Stella Vallejos Polona Umek Toni Stoycheva Fatima Annanouch Eduard Llobet Xavier Correig Patrizia De Marco Carla Bittencourt Chris Blackman 《Advanced functional materials》2013,23(10):1313-1322
Tungsten oxide nanostructures functionalized with gold or platinum NPs are synthesized and integrated, using a single‐step method via aerosol‐assisted chemical vapour deposition, onto micro‐electromechanical system (MEMS)‐based gas‐sensor platforms. This co‐deposition method is demonstrated to be an effective route to incorporate metal nanoparticles (NP) or combinations of metal NPs into nanostructured materials, resulting in an attractive way of tuning functionality in metal oxides (MOX). The results show variations in electronic and sensing properties of tungsten oxide according to the metal NPs introduced, which are used to discriminate effectively analytes (C2H5OH, H2, and CO) that are present in proton‐exchange fuel cells. Improved sensing characteristics, in particular to H2, are observed at 250 °C with Pt‐functionalized tungsten oxide films, whereas non‐functionalized tungsten oxide films show responses to low concentrations of CO at low temperatures. Differences in the sensing characteristics of these films are attributed to the different reactivities of metal NPs (Au and Pt), and to the degree of electronic interaction at the MOX/metal NP interface. The method presented in this work has advantages over other methods of integrating nanomaterials and devices, of having fewer processing steps, relatively low processing temperature, and no requirement for substrate pre‐treatment. 相似文献
59.
Rodrigo F. P. Martins Arman Ahnood Nuno Correia Luís M. N. P. Pereira Raquel Barros Pedro M. C. B. Barquinha Ricardo Costa Isabel M. M. Ferreira Arokia Nathan Elvira E. M. C. Fortunato 《Advanced functional materials》2013,23(17):2153-2161
The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics. 相似文献
60.
Carla Ferreri Anna Sansone Chryssostomos Chatgilialoglu Rosaria Ferreri Javier Amzaga Mercedes Caro Burgos Sara Arranz Itziar Tueros 《International journal of molecular sciences》2022,23(11)
Fatty acids have an important place in both biological and nutritional contexts and, from a clinical point of view, they have known consequences for diseases’ onset and development, including cancer. The use of fatty acid-based food and nutraceuticals to support cancer therapy is a multidisciplinary subject, involving molecular and clinical research. Knowledge regarding polyunsaturated fatty acids essentiality/oxidizability and the role of lipogenesis-desaturase pathways for cell growth, as well as oxidative reactivity in cancer cells, are discussed, since they can drive the choice of fatty acids using their multiple roles to support antitumoral drug activity. The central role of membrane fatty acid composition is highlighted for the application of membrane lipid therapy. As fatty acids are also known as biomarkers of cancer onset and progression, the personalization of the fatty acid-based therapy is also possible, taking into account other important factors such as formulation, bioavailability and the distribution of the supplementation. A holistic approach emerges combining nutra- and pharma-strategies in an appropriate manner, to develop further knowledge and applications in cancer therapy. 相似文献