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[en] Effects of rate of pressure application and forms and type of sample on porosity and pore size distribution of concrete estimated through mercury intrusion porosimetry (MIP) are presented in this experimental work. Two different forms of concrete sample, namely, crushed chunks of concrete and small core drilled out from the concrete beam specimens, were used for this study. The results exhibit that the rate of pressure application in mercury porosimetry has little effect on porosity and pore size distribution of concrete. It is also demonstrated that small cores drilled out from large concrete specimens are preferable as samples for performing porosimetry test on concrete
[en] Permeation quality of laboratory cast concrete beams was determined through initial surface absorption test (ISAT). The pore system characteristics of the same concrete beam specimens were determined through mercury intrusion porosimetry (MIP). Data so obtained on the measured initial surface absorption rate of water by concrete and characteristics of pore system of concrete estimated from porosimetry results were used to develop correlations between them. Through these correlations, potential of MIP in assessing the durability quality of concrete in actual structure is demonstrated
[en] In this study, in situ strength of concrete was determined through compression test of cores drilled out from laboratory cast beams. The apparent porosity and pore size distribution of the same concrete were determined through mercury intrusion porosimetry, performed on small-drilled cores. The normal-strength concrete mixes used in the experimental investigation were designed to exhibit a wide variation in their strengths. To ensure further variation in porosity, pore size distribution and strength, two modes of compaction, two varieties of coarse aggregates, different levels of age, curing period and exposure condition of concrete were also introduced in experimental scheme. With the data so generated, an appraisal of the most frequently referred relationships involving strength, porosity and pore size of cement-based materials was carried out. Finally, a new empirical model relating the in situ strength of concrete with porosity, pore size characteristics, cement content, aggregate type, exposure conditions, etc., is presented
[en] Abstracts: Although Metastatic-tumor antigen 1 (MTA1) is differentially expressed in metastatic cancer and coregulates the status and activity of nuclear receptors, its role upon estrogen receptor β (ERβ) – a potent tumor suppressor, remains poorly understood. Here we investigated whether MTA1 regulates the expression and functions of ERβ, an ER isoform predominantly expressed in salivary gland cancer cells. We found that the depletion of the endogenous MTA1 in the HSG and HSY salivary duct carcinoma cell lines enhances the expression of ERβ while MTA1 overexpression augmented the expression of ERβ in salivary duct carcinoma cells. Furthermore, MTA1 knockdown inhibited the proliferations and invasion of HSG and HSY cells. The noted ERβ downregulation by MTA1 overexpression involves the process of proteasomal degradation, as a proteasome inhibitor could block it. In addition, both MTA1 knockdown and ERβ overexpression attenuated the cell migration and inhibited the ERK1/2 signaling in the both cell lines. These findings imply that MTA1 dysregulation in a subset of salivary gland cancer might promote aggressive phenotypes by compromising the tumor suppressor activity of ERβ, and hence, MTA1-ERβ axis might serve a new therapeutic target for the salivary gland cancer. - Highlights: • MTA1 silencing upregulates ERβ expression in salivary gland carcinoma cells. • MTA1 overexpression downregulates ERβ expression via proteasomal degradation. • Upregulation of ERβ expression inhibits cell migration and ERK signaling. • MTA1 knockdown inhibits cell proliferation and invasion
[en] The electrochemical oxidation of alkylamines provides a method for modification of carbon, and other surfaces via formation of a radical amine that reacts with the surface. Direct electrochemical oxidation of an alkylamine functional group of a redox complex provides a simple route to preparation of a redox active layer on carbon surfaces. Here we report on oxidation of an osmium redox complex, containing an alkylamine ligand distal to the metal co-ordination site, on carbon electrodes to directly produce a redox active film on the surface. The presence of the redox-active layer of osmium complexes is confirmed by cyclic voltammetry and X-Ray photoelectron spectroscopy. The average surface coverage of the attached film upon electrolysis of an [Os(2,2′-bipyridine)_2(4-aminomethylpyridine)Cl].PF_6 complex is 0.84 (± 0.3) × 10"−"1"0 moles cm"−"2, demonstrating that coverages close to that predicted for a close-packed monolayer of complex is attained. The bioelectrocatalytic activity of the modified electrode was evaluated for oxidation of glucose in presence of glucose oxidase in solution. Hence, electrochemical coupling of alkylamine functionalised osmium redox complexes provides a simple and efficient methodology for obtaining redox active monolayers on carbon surfaces with potential applications to biosensor and biofuel cell device development
[en] Impingement of energetic particles/ions on material surfaces is of great interest as these impacts give rise to various interesting phenomena, such as sputtering, back-scattering, crater formation, emission of electrons and photons from material surfaces etc. Surface erosion occurring in the plasma-facing material of nuclear fusion reactors reduce their performance and this motivated the course of the current work in understanding the underlying physics of solid–particle interactions. In the present work, we have studied sputtering, crater formation and its characteristics on the surface of a plasma-facing material due to the impact of a low to high energy dust particle (a conglomerate of a few to a thousand atoms) using the molecular dynamics method. Sputtering yield, excavated atoms from the crater, crater depth, height of crater rim, radius and aspect ratio of the crater are calculated for a range of incident energies (10 eV to 10 keV), and the variation of these parameters with varying size (formed of 14, 32, 64 atoms) of dust particle at different temperatures of the target material are computed.
[en] The thorough studies conducted on water hydraulic solenoid operated directional valve for Indian Pressurised Heavy Water Reactors (PHWRs) were helpful in maintenance of the old valves and for making spares indigenously. Indigenous manufacture of these valves has been started based on the studies. (author). 4 figs
[en] For PFBR off-load refuelling is envisaged. The transfer operations within the main vessel will be carried out by a straight-pull machine, whereas transfers between a position in the main vessel to another on the storage side will be carried out by Inclined Fuel Translift Mechanism (IFTM). The paper deals with the requirements of IFTM and the possible concepts which were considered for it. The different concepts considered were Swing type system, Rotary X-frame system and Rotating shielded system. The basis of selection of Rotating shielded leg system is presented along with its salient features. (author)
[en] Drug induced pulmonary toxicity is not uncommon with the use of various chemotherapeutic agents. Cyclophosphamide is a widely used chemotherapeutic drug in the treatment of breast cancer. Although rare, lung toxicity has been reported with cyclophosphamide use. Detection of bleomycin induced pulmonary toxicity and pattern of "1"8F-fluorodeoxyglucose ("1"8F-FDG) uptake in lungs on fluorodeoxyglucose positron emission tomography-computed tomography ("1"8F-FDG PET-CT) has been elicited in literature in relation to lymphoma. However, limited data is available regarding the role of "1"8F-FDG PET-CT in monitoring drug induced pulmonary toxicity in breast cancer. We here present two cases of cyclophosphamide induced drug toxicity. Interim "1"8F-FDG PET-CT demonstrated diffusely increased tracer uptake in bilateral lung fields in both these patients. Subsequently there was resolution of lung uptake on "1"8F-FDG PET-CT scan post completion of chemotherapy. These patients did not develop significant respiratory symptoms during chemotherapy treatment and in follow up
[en] In this paper, effect of thermal radiation on the unsteady 3-dimensional flow of nanofluid (Cu-water) past a vertical flat surface is examined in rotating frame of reference. The surface is assumed to be executing harmonic oscillations about a constant mean velocity. By the use of appropriate transformations, governing equations and boundary conditions are obtained in dimensionless form. Due to non-availability of analytical methods for the solution of 3D boundary-layer equations, we have chosen to employ explicit finite difference method to obtain the solution of the set of equations, and utilized MATLAB to extract information about the profiles of velocity and temperature, skin-friction and rate of heat transfer. Von-Neumann stability analysis of this scheme is also done to ensure the accuracy of solutions and boundedness of errors. The results reveal that thermal radiation elevates the rate of heat transfer in primary direction whereas rotation has opposite influence on it.