Strain engineering in single-, bi- and tri-layer MoS2, MoSe2, WS2 and WSe2

Nano Research - Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS2, MoSe2, WS2 and WSe2. In this work we provide a thorough...     

Crosslinked,biodegradable polyurethanes for precision-porous biomaterials: Synthesis and properties

Crosslinked poly(ester urethane)s and their acrylate derivatives based on trifunctional polycaprolactone and trifunctional aliphatic isocyanates were synthesized. Biodegradable scaffolds with uniform, controlled micron-scale porosity were fabricated with these materials. Mechanical and swelling properties of monolithic and microporous materials were studied. Cytotoxicity, hydrolytic, and enzymatic degradation and their effects on mechanical properties of the biodegradable scaffolds were investigated. The polymer degradation products were found not to be cytotoxic at moderate concentrations and to permit cell attachment and spreading. Degradation rates and mechanical properties could be tuned to desired performance criteria for a given application by adjusting crosslink density and the ratio of hard segment to soft segment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48943.     

Effect of Bath Depth and Nozzle Geometry on Spout Height in Submerged Gas Injection at Bottom

Metallurgical and Materials Transactions B - Spout height is a widely used parameter to quantitatively analyze the performance of the submerged gas injection in industrial applications. However,...     

ITER vacuum vessel: Design review and start of procurement process

The ITER vacuum vessel (VV) is one of the most critical components in the ITER project. It is on the critical path in the construction schedule and it is also a safety important class component (SIC), providing the first confinement barrier.As a result of reviews and the latest physics analyses, design requirements have been updated (e.g. ELM/VS coils) and a few design changes have to be implemented. This paper covers the updates of the VV vertical and horizontal EM load conditions during asymmetric VDEs, the design analysis of the ELM/VS coils and their interfaces to the VV, the blanket manifold design and the preparation of the technical specification in preparation for the procurement arrangement to be signed.     

Regulation of polyisoprenylated methylated protein methyl esterase by polyunsaturated fatty acids and prostaglandins

Polyisoprenylation is a set of secondary modifications involving proteins whose aberrant activities are implicated in cancers and degenerative disorders. The last step of the pathway involves an ester‐forming polyisoprenylated protein methyl transferase‐ and hydrolytic polyisoprenylated methylated protein methyl esterase (PMPMEase)‐catalyzed reactions. Omega‐3 and omega‐6 PUFAs have been linked with antitumorigeneis and tumorigenesis, respectively. PUFAs are structurally similar to the polyisoprenyl groups and may interfere with polyisoprenylated protein metabolism. It was hypothesized that PUFAs may be more potent inhibitors of PMPMEase than their more polar oxidative metabolites, the prostaglandins. As such, the relative effects of PUFAs and prostaglandins on PMPMEase could explain the association between cyclooxygenase‐2 (COX‐2) expression in tumors, the chemopreventive effects of the non‐steroidal anti‐inflammatory (NSAIDs) COX‐2 inhibitors and PUFAs. PUFAs such as AA, EPA, and DHA inhibited PMPMEase activity with K_i values of 0.12–3.7 µM. The most potent prostaglandin was 63‐fold less potent than AA. The PUFAs were also more effective at inducing neuroblastoma cell death at physiologically equivalent concentrations. The lost PMPMEase activity in AA‐treated degenerating cells was restored by incubating the lysates with COX‐1 or COX‐2. PUFAs may thus be physiological regulators of cell growth and could owe these effects to PMPMEase inhibition. Practical applications: Some PUFAs have been widely reported to have anticancer benefits. However, the molecular mechanisms for these effects are not well understood. The findings in the current paper appear to suggest that inhibition of PMPMEase may underlie their effects. They also imply that the expression of COX‐2 in various tumors may serve to convert the PUFAs into significantly less inhibitory prostaglandins. From these findings, AA and the other PUFAs, rather than being substrates for the synthesis of tumorigenic agents may actually contribute in suppressing cell proliferation. This being congruent with the lower cancer risks associated with long term use of anti‐inflammatory agents, the practical implications will likely include the nutritional and/or therapeutic management of cancer with the goal of maintaining suitable levels of the fatty acids in tissues.