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A new shaft element is proposed for viscoelastic rotors in a spinning frame considering the shear deformation in addition to bending deformation. The Maxwell–Wiechert model is considered here to replicate linear viscoelastic behavior. This model considers additional internal damping displacement variables between elastic and viscous elements and the stress depends not only on the elastic strain and elastic strain rate, but also on additional strains and their rates corresponding to the damping variables. The present work assumes that these additional strains can be derived from continuous fictitious displacement variables, which in turn are interpolated from their nodal values using the Timoshenko beam shape functions. Therefore, in addition to the standard degrees of freedom for a three-dimensional shaft, extra degrees of freedom are defined at the nodes. The finite element matrices are assembled in state space. The time domain equations are then used for stability analysis and computation of response to a unit step load and an unbalance. [ABSTRACT FROM AUTHOR]

The formation of nanocrystals in Zr-based alloys through three different routes, viz by rapid solidification of alloys, by crystallization of rapidly solidified metallic glasses and by crystallization of bulk metallic glasses has been described. The nanocrystal forming behaviors of rapidly solidified metallic glasses and bulk metallic glasses have been compared and contrasted. The rapidly solidified alloys, which have been examined for this purpose, are Zr76Fe24-xNix (x = 0,4,8,12,16,24) and Zr69.5Cu12Ni11Al7.5. In the Zr69.5Cu12Ni11Al7.5 alloy, formation of a quasicrystalline phase was observed on crystallization. Bulk glass having the composition Zr52Ti6Al10Cu18Ni14 has been produced by copper mould casting. This has been crystallized in order to obtain nanocrystalline phases having Zr2Ni and Zr2Cu structures. The nanocrystalline and the nanoquasicrystalline microstructures have been examined in considerable detail in order to find out the nature of the various types of interfaces in them. Particularly the nanograin boundaries were examined by high-resolution transmission electron microscope (HREM) and their structure has been compared with that of the grain boundary in large grained material. The change in nature of these interfaces and their number with coarsening of the nanocrystal is also investigated. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses operations research.

Cellular temperature and pH govern many cellular physiologies, especially of cancer cells. Besides, attaining higher cellular temperature plays key role in therapeutic efficacy of hyperthermia treatment of cancer. This requires bio-compatible, non-toxic and sensitive probe with dual sensing ability to detect temperature and pH variations. In this regard, fluorescence based nano-sensors for cancer studies play an important role. Therefore, a facile green synthesis of orange carbon nano-dots (CND) with high quantum yield of 90% was achieved and its application as dual nano-sensor for imaging intracellular temperature and pH was explored. CND was synthesized from readily available, bio-compatible citric acid and rhodamine 6G hydrazide using solvent-free and simple heating technique requiring purification by dialysis. Although the particle size of 19 nm (which is quite large for CND) was observed yet CND exhibits no surface defects leading to decrease in photoluminescence (PL). On the contrary, very high fluorescence was observed along with good photo-stability. Temperature and pH dependent fluorescence studies show linearity in fluorescence intensity which was replicated in breast cancer cells. In addition, molecular nature of PL of CND was established using pH dependent fluorescence study. Together, the current investigation showed synthesis of highly fluorescent orange CND, which acts as a sensitive bio-imaging probe: an optical nano-thermal or nano-pH sensor for cancer-related studies., (© 2021. The Author(s).)

The reaction of freshly prepared Na[In(SeCH 2 C 6 H 5 ) 4 ] with the mixture of CuCl and triphenylphosphine in methanol yielded [(PPh 3 ) 2 CuIn(SeCH 2 C 6 H 5 ) 4 ]. The X-ray structure of the complex revealed the monomeric form of [(Ph 3 P) 2 Cu(μ-SeCH 2 Ph) 2 In(SeCH 2 Ph) 2 ] consisting of tetrahedral Cu(i) and In(iii) centers, bridged by two benzyl selenolate ligands. The complex on pyrolysis in a furnace or in oleylamine/HDA yielded tetragonal CuInSe 2 . The morphology and composition of nanostructures were investigated by pXRD, SEM, TEM and EDX analysis. The band gap of the CuInSe 2 nanostructures, obtained from pyrolysis in HDA and OA has been deduced from DRS as 1.85 and 1.86 eV, respectively., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

The ameliorative properties of bioactive compound andrographolide (ANDRO), aqueous extract of Andrographis paniculata (AE-AP) and vitamin E (vit.E) were tested against nicotine induced liver, kidney, heart, lung and spleen toxicity. A group of male Wistar rats were intraperitoneally administered vehicle, nicotine (1mg/kg body weight/day), nicotine+ANDRO (250mg/kg body weight/day), nicotine+AE-AP (250mg/kg body weight/day) and nicotine+vit.E (50mg/kg body weight/day) for the period of 7 days. The significantly increased levels of lipid peroxidation, protein oxidation and the decreased antioxidant enzyme status were noted in nicotine treated group as compared to vehicle treated group. ANDRO, AE-AP and vit.E significantly reduced the lipid peroxidation, protein oxidation and increased the antioxidant enzyme status. This indicates A. paniculata and vit.E may act as putative protective agent against nicotine induced tissue injury and may pave a new path to develop suitable drug therapy., (Copyright © 2007 Elsevier B.V. All rights reserved.)