Dry Machining of AA7075 by H-DLC Coated Carbide End Mill

AbstractPresent investigation evaluates the performance of a hydrogenated diamond like carbon (H-DLC) coating on carbide end mills during machining of an Al-Zn-Mg based alloy i.e. AA7075. Although diamond is known to be the most potential hard coating on carbide tools to deal with the challenges of machining aluminium, DLC coating offers economic solution in dealing with this material at medium cutting speeds. Present study explores the feasibility of using a H-DLC coating, which is eventually softer than non-hydrogenated DLC, in machining this alloy and compares its performance with that of uncoated carbide tools under dry environment. In terms of surface finish and cutting force this H-DLC coated tool substantially outperformed uncoated carbide one in the cutting speed range of 60 to 180 m/min. The coating was able to substantially arrest built up edge (BUE) formation, however, found to be with minor trace of built up layer (BUL)

5-Fluoro-6′H,7′H,8′H-spiro­[indoline-3,7′-pyrano[3,2-c:5,6-c′]di-1-benzopyran]-2,6′,8′-trione

In the title compound, C26H12FNO6, the central pyran ring and both benzopyran systems are nonplanar, having total puckering amplitudes of 0.139 (2), 0.050 (1) and 0.112 (2) Å, respectively. The central pyran ring adopts a boat conformation. The crystal structure is stabilized by C—H⋯O, N—H⋯O, N—H⋯F and C—H⋯π inter­actions

Facing challenges in an ageing world

Editorial.The sponsorship of the following contributors made possible the meeting: Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, Springer Publishers, International Coenzyme Q10 Association, Sociedad Española de Biología Celular, Universidad Internacional de Andalucía, Junta de Andalucía, Cien por Cien Natural, Pharma Nord Denmark, C. Viral, ThermoFisher Scientific and Cultek.Peer Reviewe

Distributed Design of Controllable and Robust Networks using Zero Forcing and Graph Grammars

This paper studies the problem of designing networks that are strong structurally controllable, and robust simultaneously. For given network specifications, including the number of nodes $N$, the number of leaders $N_L$, and diameter $D$, where $2 \le D \le N/N_L$, we propose graph constructions generating strong structurally controllable networks. We also compute the number of edges in graphs, which are maximal for improved robustness measured by the algebraic connectivity and Kirchhoff index. For the controllability analysis, we utilize the notion of zero forcing sets in graphs. Additionally, we present graph grammars, which are sets of rules that agents apply in a distributed manner to construct the graphs mentioned above. We also numerically evaluate our methods. This work exploits the trade-off between network controllability and robustness and generates networks satisfying multiple design criteria.Comment: American Control Conference (ACC 2023

Redox regulation of type-I inositol trisphosphate receptors in intact mammalian cells.

A sensitization of inositol 1,4,5-trisphosphate receptor (IP3R)-mediated Ca2+ release is associated with oxidative stress in multiple cell types. These effects are thought to be mediated by alterations in the redox state of critical thiols in the IP3R, but this has not been directly demonstrated in intact cells. Here, we utilized a combination of gel-shift assays with MPEG-maleimides and LC-MS/MS to monitor the redox state of recombinant IP3R1 expressed in HEK293 cells. We found that under basal conditions, ∼5 of the 60 cysteines are oxidized in IP3R1. Cell treatment with 50 μm thimerosal altered gel shifts, indicating oxidation of ∼20 cysteines. By contrast, the shifts induced by 0.5 mm H2O2 or other oxidants were much smaller. Monitoring of biotin-maleimide attachment to IP3R1 by LC-MS/MS with 71% coverage of the receptor sequence revealed modification of two cytosolic (Cys-292 and Cys-1415) and two intraluminal cysteines (Cys-2496 and Cys-2533) under basal conditions. The thimerosal treatment modified an additional eleven cysteines, but only three (Cys-206, Cys-767, and Cys-1459) were consistently oxidized in multiple experiments. H2O2 also oxidized Cys-206 and additionally oxidized two residues not modified by thimerosal (Cys-214 and Cys-1397). Potentiation of IP3R channel function by oxidants was measured with cysteine variants transfected into a HEK293 IP3R triple-knockout cell line, indicating that the functionally relevant redox-sensitive cysteines are predominantly clustered within the N-terminal suppressor domain of IP3R. To our knowledge, this study is the first that has used proteomic methods to assess the redox state of individual thiols in IP3R in intact cells. © 2018 Joseph et al