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991.
Elena Fiorese Franco Bonollo Eleonora Battaglia Giorgio Cavaliere 《International Journal of Cast Metals Research》2017,30(1):6-12
Lubrication plays a significant role among the processes that affect aesthetic quality in die casting. Nevertheless, comprehensive investigations are still missing in literature. In this paper, the effect of lubrication is investigated and optimized, by focusing on its influence on the die temperature. Indeed, since the surface quality of castings is related to the interaction between melt and die, lubrication allows ejection of castings without generating defects and cooling of the die, by preserving its surface. Hence, the die temperature should be accurately selected and spraying should be improved to achieve the optimal temperature. In the experimentation proposed, the lubricant release agent percentage and the lubrication duration have been varied to trade-off between some conflicting effects, while making the die temperature approach the ‘Nukiyama point’. At the same time, reduction of the cycle time has been obtained. The results corroborate the approach, since defects are reduced after optimization. 相似文献
992.
Bernardinetti Giorgio Di Cristofaro Dimitri Bianchi Giuseppe 《Journal in Computer Virology》2022,18(4):315-331
Journal of Computer Virology and Hacking Techniques - The ability to evade Antivirus analyses is a highly coveted goal in the cybersecurity field, especially in the case of Red Team operations... 相似文献
993.
Carbone Giorgio Giuseppe Manno Daniela Serra Antonio Buccolieri Alessandro 《Journal of Materials Science》2022,57(3):1714-1726
Journal of Materials Science - Copper nanoparticles (CuNPs) as well as those of other noble metals show unique features that are not observed in bulk copper. Despite the enormous potential of... 相似文献
994.
Spadoni G Bedini A Guidi T Tarzia G Lucini V Pannacci M Fraschini F 《ChemMedChem》2006,1(10):1099-1105
Herein we report attempts to optimize the pharmacological properties of 5-(2-hydroxyethoxy)-N-acetyltryptamine (5-HEAT), a melatonin receptor ligand previously described by us. Several 5-substituted and 2,5-disubstituted N-acyltryptamines were synthesized and evaluated in vitro for the human cloned MT(1) and MT(2) receptors. From this series of N-acyltryptamines the 2-bromo derivative (5 c) retains the interesting efficacy profile of 5-HEAT and shows increased melatonin receptor affinities; it represents one of the first examples of a high-affinity MT(1) agonist/MT(2) antagonist. Some other full agonists for both melatonin receptors which exhibit similar or increased affinity relative to that of melatonin were obtained. 相似文献
995.
Tarzia G Duranti A Gatti G Piersanti G Tontini A Rivara S Lodola A Plazzi PV Mor M Kathuria S Piomelli D 《ChemMedChem》2006,1(1):130-139
Fatty acid amide hydrolase (FAAH) is a serine hydrolase that catalyzes the intracellular hydrolysis of fatty acid ethanolamides such as anandamide and oleoylethanolamide. Targeting this enzyme may have important therapeutic potentials owing to the multiple physiological roles of these amides. Cyclohexylcarbamic acid biphenyl-3-yl ester (URB524) was one of the most promising FAAH inhibitors so far described. We report the modulation of the electronic and steric features of the proximal phenyl ring of this compound by introducing a series of substituents at the ortho and para positions. pIC50 values were found to correlate with molecular features thought to be involved in the recognition step such as steric hindrance and hydrogen-bonding ability. Derivatives with small polar groups at the para position of the proximal phenyl ring were slightly better FAAH inhibitors than the parent compound URB524. 相似文献
996.
997.
3‐Aminoazetidin‐2‐one Derivatives as N‐Acylethanolamine Acid Amidase (NAAA) Inhibitors Suitable for Systemic Administration 下载免费PDF全文
Dr. Annalisa Fiasella Dr. Andrea Nuzzi Dr. Maria Summa Dr. Andrea Armirotti Dr. Glauco Tarozzo Prof. Giorgio Tarzia Prof. Marco Mor Dr. Fabio Bertozzi Dr. Tiziano Bandiera Prof. Daniele Piomelli 《ChemMedChem》2014,9(7):1602-1614
N‐Acylethanolamine acid amidase (NAAA) is a cysteine hydrolase that catalyzes the hydrolysis of endogenous lipid mediators such as palmitoylethanolamide (PEA). PEA has been shown to exert anti‐inflammatory and antinociceptive effects in animals by engaging peroxisome proliferator‐activated receptor α (PPAR‐α). Thus, preventing PEA degradation by inhibiting NAAA may provide a novel approach for the treatment of pain and inflammatory states. Recently, 3‐aminooxetan‐2‐one compounds were identified as a class of highly potent NAAA inhibitors. The utility of these compounds is limited, however, by their low chemical and plasma stabilities. In the present study, we synthesized and tested a series of N‐(2‐oxoazetidin‐3‐yl)amides as a novel class of NAAA inhibitors with good potency and improved physicochemical properties, suitable for systemic administration. Moreover, we elucidated the main structural features of 3‐aminoazetidin‐2‐one derivatives that are critical for NAAA inhibition. 相似文献
998.
Multiscale modeling of protein adsorption and transport in macroporous and polymer‐grafted ion exchangers 下载免费PDF全文
Joseph E. Basconi Giorgio Carta Michael R. Shirts 《American Institute of Chemical Engineers》2014,60(11):3888-3901
A multiscale model is presented to elucidate protein adsorption and transport behaviors in ion‐exchange chromatography (IEC) adsorbent particles that have either an open pore structure or charged dextran polymers grafted into the pores. Molecular dynamics simulation is used to determine protein diffusion and partitioning in different regions of the adsorbent pore, and these outputs are used in numerical simulations of mass transfer to determine the intraparticle protein concentration profile and the mass‐transfer rate. Modeling results indicate that, consistent with experimental observations, protein transport can be faster in the polymer‐grafted material compared to the open pore case. This occurs when favorable partitioning of protein into the polymer‐filled pore space is combined with relatively high protein mobility within this region. The modeling approach presented here should be applicable to proteins and adsorbents with different properties, and could help elucidate the factors that control adsorption and transport in various IEC systems. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3888–3901, 2014 相似文献
999.
Manuela Antoniel Valentina Giorgio Federico Fogolari Gary D. Glick Paolo Bernardi Giovanna Lippe 《International journal of molecular sciences》2014,15(5):7513-7536
The oligomycin-sensitivity conferring protein (OSCP) of the mitochondrial FOF1 ATP synthase has long been recognized to be essential for the coupling of proton transport to ATP synthesis. Located on top of the catalytic F1 sector, it makes stable contacts with both F1 and the peripheral stalk, ensuring the structural and functional coupling between FO and F1, which is disrupted by the antibiotic, oligomycin. Recent data have established that OSCP is the binding target of cyclophilin (CyP) D, a well-characterized inducer of the mitochondrial permeability transition pore (PTP), whose opening can precipitate cell death. CyPD binding affects ATP synthase activity, and most importantly, it decreases the threshold matrix Ca2+ required for PTP opening, in striking analogy with benzodiazepine 423, an apoptosis-inducing agent that also binds OSCP. These findings are consistent with the demonstration that dimers of ATP synthase generate Ca2+-dependent currents with features indistinguishable from those of the PTP and suggest that ATP synthase is directly involved in PTP formation, although the underlying mechanism remains to be established. In this scenario, OSCP appears to play a fundamental role, sensing the signal(s) that switches the enzyme of life in a channel able to precipitate cell death. 相似文献
1000.
The transients produced by the pantograph electric arc and captured by a GSM-R antenna mounted on the roof top are characterized in the time domain and in the joint time–frequency domain, in order to quantify the noise produced on the GSM-R channels. The recorded signals are also characterized in order to evaluate the behavior of the GSM-R protocol in relation to burst noise with transients undergoing different repetition intervals. To this aim the GSM-R protocol is considered in particular with respect to data bit protection and for the relationship between signal-to-noise ratio, bit error rate and frame error rate, evaluated by repeated laboratory tests based on recorded transients. The measurements were performed on a 25 kV 50 Hz French railway line. 相似文献