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排序方式: 共有241条查询结果,搜索用时 19 毫秒
1.
Dr. Dimitra T. Pournara Anna Durner Dr. Eftichia Kritsi Alexios Papakostas Dr. Panagiotis Zoumpoulakis Prof. Dr. Annette Nicke Dr. Maria Koufaki 《ChemMedChem》2020,15(24):2530-2543
The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide ( 56 ) exhibiting the best potency with an IC50 value of 0.39 μM. 相似文献
2.
This paper deals with modeling of the phenomenon of fretting fatigue in
heterogeneous materials using the multi-scale computational homogenization technique
and finite element analysis (FEA). The heterogeneous material for the specimens consists
of a single hole model (25% void/cell, 16% void/cell and 10% void/cell) and a four-hole
model (25% void/cell). Using a representative volume element (RVE), we try to produce
the equivalent homogenized properties and work on a homogeneous specimen for the
study of fretting fatigue. Next, the fretting fatigue contact problem is performed for 3 new
cases of models that consist of a homogeneous and a heterogeneous part (single hole cell)
in the contact area. The aim is to analyze the normal and shear stresses of these models
and compare them with the results of the corresponding heterogeneous models based on
the Direct Numerical Simulation (DNS) method. Finally, by comparing the
computational time and % deviations, we draw conclusions about the reliability and
effectiveness of the proposed method. 相似文献
3.
Web of Science (WoS) and Google Scholar (GS) are prominent citation services with distinct indexing mechanisms. Comprehensive knowledge about the growth patterns of these two citation services is lacking. We analyzed the development of citation counts in WoS and GS for two classic articles and 56 articles from diverse research fields, making a distinction between retroactive growth (i.e., the relative difference between citation counts up to mid-2005 measured in mid-2005 and citation counts up to mid-2005 measured in April 2013) and actual growth (i.e., the relative difference between citation counts up to mid-2005 measured in April 2013 and citation counts up to April 2013 measured in April 2013). One of the classic articles was used for a citation-by-citation analysis. Results showed that GS has substantially grown in a retroactive manner (median of 170 % across articles), especially for articles that initially had low citations counts in GS as compared to WoS. Retroactive growth of WoS was small, with a median of 2 % across articles. Actual growth percentages were moderately higher for GS than for WoS (medians of 54 vs. 41 %). The citation-by-citation analysis showed that the percentage of citations being unique in WoS was lower for more recent citations (6.8 % for citations from 1995 and later vs. 41 % for citations from before 1995), whereas the opposite was noted for GS (57 vs. 33 %). It is concluded that, since its inception, GS has shown substantial expansion, and that the majority of recent works indexed in WoS are now also retrievable via GS. A discussion is provided on quantity versus quality of citations, threats for WoS, weaknesses of GS, and implications for literature research and research evaluation. 相似文献
4.
This paper presents a performance analysis of spaceborne bistatic Synthetic Aperture Radar (SAR) for Earth observation. Since a bistatic system requires the simultaneous use of two spatially separated antennae, this paper refers to the European Space Agency ENVISAT-1 ASAR as the master mission, i.e. reflected echoes collected by ASAR are gathered also by a receiving-only slave antenna, which is on board a small satellite. Depending on orbit configuration, two mission profiles could be envisaged: two satellites flying along parallel orbits with different ascending nodes, or in one orbit plane with adequate angular separation. It is assumed that ENVISAT-1 is non-cooperative; therefore, signal synchronization and swath overlap and antenna separation control are committed to receiving-only spacecraft. To gain further insight into system geometric and radiometric characteristics and accuracy, several simulations are performed by using a computer code, which accounts for spacecraft orbit and attitude dynamics, sensor pointing geometry and Earth rotation. Numerical results and plots show the potentiality of the system for quite accurate three-dimensional measurements. In particular, thanks to system geometry, it is possible to compute target position and slant range components of velocity. Finally, further potential applications are outlined, also considering additional spin-offs for the master mission. 相似文献
5.
Marinos Vassilis Stoumpos Georgios Papouli Dimitra Papazachos Costas 《Bulletin of Engineering Geology and the Environment》2019,78(3):1795-1813
Bulletin of Engineering Geology and the Environment - This present paper presents an adopted methodology for Micro Tunnel Boring Machine (TBM) selection, based on the results of a... 相似文献
6.
Antimo Barbato Antonio Capone Giuliana Carello Maurizio Delfanti Davide Falabretti Marco Merlo 《Energy Efficiency》2014,7(6):1013-1052
With the Smart Grid revolution and the increasing interest in renewable energy sources, the management of the electricity consumption and production of individual households and small residential communities is becoming an essential element of new power systems. The electric energy chain can greatly benefit from a flexible interaction with end-users based on the optimization of load profiles and the exploitation of local generation and energy storage. This paper proposes a framework for the development of a complete energy management system for individual residential units and small communities of domestic users, taking into account both the power system and the final users’ perspectives. All the main elements of the framework are considered, and contributions are provided on the users’ habits profiling, electricity generation forecast, energy load, and storage optimization. Specifically, we propose a linear regression model to predict the photovoltaic panels production, a stochastic method to forecast the home appliances usage, and two optimization models to optimize the electricity management of residential users with the goal of minimizing their bills. The study shows that it is possible to reduce the energy bill of residential users through the electricity optimization driven by dynamic energy prices. Moreover, remarkable improvements of the electric grid efficiency can be achieved with the cooperation among users, confirming that services for the coordination of the demand of groups of users allow huge benefits on the power system performance. 相似文献
7.
8.
This paper introduces a joint planning and management optimization approach for cellular networks to limit energy consumption while guaranteeing QoS and minimizing operators Capex and Opex. The modeling framework shows that an effective energy-efficient operation depends on the planning decisions. Conversely, it also shows that planning with energy management operation in view yields more versatile topologies than more traditional models based only on Capex. Results for LTE networks are provided and show that savings up to 65% in energy expenses are possible with slight increases in capital investments. 相似文献
9.
10.
Luigi Capone Yassin A. Hassan Rodolfo Vaghetto 《Nuclear Engineering and Design》2011,241(12):4775-4782
The development of a new concept for a high temperature gas cooled reactor is strictly correlated to the Reactor Cavity Cooling System (RCCS) design. This is the latest heat sink designed to ensure the cooling down of the vessel and other structural materials during an accident scenario. An experimental facility was built at Texas A&M to quantitatively analyze heat transfer phenomena and the air flow regime inside the reactor cavity. The thermal measurements were performed using 18 thermocouples mounted on the vessel surface, 8 on the external surface of one of the cooling pipes and 24 on a movable rack that captures the axial temperature profile inside the cavity. Flow regime measurements were performed with Particle Tracking Velocimetry techniques (PTV), using a high speed camera and spraying a special dust in the cavity for the tracking. The results demonstrate that the main heat transfer mode inside the cavity is the radiation (about 80%); also, they show the complexity of the flow regime inside the cavity due to natural circulation. The experimental conditions were a vessel surface temperature of about 300 °C heated at fixed power and different flow rates for the cooling pipes. 相似文献