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141.
Stefan Weinschenk Carsten Weiss Justus Benrath Volker von Baehr Thomas Strowitzki Manuel Feißt 《International journal of molecular sciences》2022,23(6)
Background. Local anesthetics (LAs) have potent anti-inflammatory properties. Inflammatory down-regulation is crucial in diseases with overactive immune reactions, such as acute respiratory distress syndrome (ARDS) and chronic inflammation. We investigated the influence of four LAs, procaine, lidocaine, mepivacaine, and bupivacaine, on the reduction of tumor necrosis factor-alpha (TNF-α) secretion in lipopolysaccharide (LPS)-activated human leucocytes. Methods. Blood samples of 28 individuals were stimulated with LPS. The reduction of TNF-α production by each of the four LAs added (0.5 mg/mL) was measured and correlated with biometric variables. A response was defined as reduction to <85% of initial levels. Results. All four LAs down-regulated the TNF-α secretion in 44–61%: Bupivacaine (44.4%), lidocaine (61.5%), mepivacaine (44.4%), and procaine (50% of the individuals, “responders”). The TNF-α secretion was reduced to 67.4, 68.0, 63.6, and 67.1% of the initial values in responders. The effects in both patients and healthy persons were the same. Interindividual responses to LAs were not correlated with the duration or type of complaints, basal TNF-α serum level, sex, BMI, or age of responders. Conclusions. Four clinically relevant LAs (amid-LA and ester-LA) attenuate the inflammatory response provoked by LPS. They are potential candidates for drug repositioning in treating overactive immune reactions and chronic inflammation. 相似文献
142.
Stability of wood fast pyrolysis oil 总被引:6,自引:0,他引:6
This study evaluates the effects of storage conditions on physical and chemical properties of biomass fast pyrolysis oils exposed to elevated temperatures over extended periods of time. It was performed on oak pyrolysis oil generated in the NREL vortex reactor. Oil samples were stored at three temperatures: 37, 60 and 90°C in glass vessels. Properties of the oils were measured after hours of storage at 90°C, and after days or weeks at lower temperatures. Chemical changes in the oils were measured using GPC (molecular weight distribution) and FTIR spectroscopy. The oil remained a single phase throughout the studied conditions. Its pH was not affected by storage. The water content, viscosity and molecular weight of the oil increased with the time and temperature of storage. First-order reaction kinetics were successfully used to predict changes in molecular weight of the stored oil. FTIR provided evidence that etherification or esterification are mechanisms for condensation of the oil during storage. 相似文献
143.
District heating networks can technically enable energy-related co-operations between energy-intensive industries and municipal energy companies. The most common form of co-operation is to utilise industrial waste heat as the primary energy source in district heating networks. However, another type of co-operation is to jointly own a plant that produces both process steam for the industry and hot water for district heating. In this article, eight Swedish energy co-operations are studied and the main focus is on the process leading to co-operations of this kind. Different aspects of factors that facilitate or obstruct the start up and continuous daily operation of a co-operation are discussed. The main conclusion is that while the primary reasons for the foundation of such co-operations are favourable techno-economic factors, this is not enough for a co-operation to emerge. This study highlights the importance of people with a real ambition to co-operate in both parties in the co-operations. 相似文献
144.
145.
Industrial development focuses on multifunctional components due to rising requirements regarding e.g. light weight and security. A beneficial possibility to extend the functionality of structural components produced by metal forming is the usage of screen printed metal blanks. During the printing process insulating and electric inks are applied. The examined printed layer structure consists of three insulating full area layers and one conductive layer in the form of strain gauges. The two applied inks are solvent-based and printed with a half-automatic machine. To improve the adhesion and electric functionality, the impact of different mechanical and physical surface pre-treatments on the electrical characteristics is investigated in tensile tests. In particular, abrasive peening, ball peening, grinding and polishing (mechanical) and in addition plasma and corona technology (physical) were utilised. Contrary to expectations, the surface pre-treatment does not affect the adhesion to the steel sheet. The cracking of the printed strain gauges takes place prior to the delamination of the coating. Explanatory models are elaborated. They are based on the measurements of roughness, surface energy, edge sharpness and the electrical resistance of printed conductive structures before, during and after forming. 相似文献
146.
Results obtained in the pulse irradiation tests performed on segmented fuel elements in the Romanian Annular Core Pulse Reactor (ACPR) are discussed below. Tests included the effects of initial element internal pressure and a wide range of energy deposition on the fuel element behavior. All tests were conducted in stagnant water at room temperature and atmospheric pressure inside the capsule. The fuel elements were instrumented with thermocouples for cladding surface temperature measurement. Transient histories of reactor power, cooling water pressure, fuel element internal pressure and cladding temperature were recorded during the tests. The fuel elements were subjected to total energy depositions from 70 to 265 cal g−1 UO2. Cladding failure mechanism and the failure threshold have been established. The fuel failure mechanism is a burst type and is very similar to LOCA failure mechanism even though the rate energy deposition is higher in the ACPR tests. At higher energy deposition brittle cladding fracture near endcap weld region can be produced. The failure threshold is situated between 190 and 200 cal g−1 UO2 for standard fuel rod (0.2–0.3 MPa internal pressure) and less than 160 cal g−1 UO2 for pressurized fuel rods (internal pressure between 1 and 3.0 MPa). Pre-pressurization could be an important factor to control the failure threshold energy. The experimental program is still in progress and new experiments are foreseen to be performed in the following period. 相似文献
147.
148.
Sylvain Grosjean Mirella Wawryszyn Hatice Mutlu Stefan Brse Joerg Lahann Patrick Theato 《Advanced materials (Deerfield Beach, Fla.)》2019,31(26)
Bioinspiration has emerged as an important design principle in the rapidly growing field of materials science and especially its subarea, soft matter science. For example, biological cells form hierarchically organized tissues that not only are optimized and designed for durability, but also have to adapt to their external environment, undergo self‐repair, and perform many highly complex functions. Being able to create artificial soft materials that mimic those highly complex functions will enable future materials applications. Herein, soft matter technologies that are used to realize bioinspired material structures are described, and potential pathways to integrate these into a comprehensive soft matter research environment are addressed. Solutions become available because soft matter technologies are benefitting from the synergies between organic synthesis, polymer chemistry, and materials science. 相似文献
149.
Stefan Lausberg 《真空研究与实践》2019,31(3):20-25
Modern mass spectrometers in vacuum applications The article describes the functionality of quadrupole mass spectrometers and their usage in different applications. Several examples illustrate the importance of careful interpretation of the respective spectra. Some applications allow the direct installation into a vacuum chamber while other applications require an external pump system which is only weakly connected to the vacuum chamber. 相似文献
150.
Digital technology becomes more powerful, intelligent, pervasive and ubiquitous. Ethical aspects of this development have not yet drawn the appropriate attention of researchers and engineers. This paper presents an instrument that aims at measuring the individual ethical position with regard to the design and development of computer software. The development of the Epos tool was based on two data collections. The data of the first survey (n1 = 147 participants) were used to select items and to determine the factorial structure of the questionnaire. Results show that the Epos instrument reliably assesses peoples’ ethical opinion with respect to five central components: (1) regulation, (2) data privacy, (3) domain specific knowledge, (4) societal responsibility and (5) company responsibility. In the second survey, we determined the stability of the instruments factor structure by assessing a sample of n2?=?196 participants. A confirmatory factor analysis (CFA) supported the initial factor structure. Next steps and further implications are discussed regarding the final version of the questionnaire. 相似文献