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201.
202.
Different aspects of mathematical modeling for the axial crushing of cylindrical tubes with straight fold have been discussed. The variation of circumferential strain during the formation of a fold has been taken into account. The present paper tries to answer questions such as (a) how great is the inside and outside folding, and (b) how the crushing load varies. In the present paper, the influence of the consideration of the conservation of mass on the mathematical formulation has been studied. The results of average and varying circumferential strain have also been compared. 相似文献
203.
Ullah MF Ahmad A Zubair H Khan HY Wang Z Sarkar FH Hadi SM 《Molecular nutrition & food research》2011,55(4):553-559
Scope: Worldwide geographical variation in cancer incidence indicates a correlation between dietary habits and cancer risk. Epidemiological studies have suggested that populations with high isoflavone intake through soy consumption have lower rates of breast, prostate, and colon cancer. Isoflavone genistein in soybean is considered a potent chemopreventive agent against cancer. Although several mechanisms have been proposed, a clear anticancer action mechanism of genistein is still not known. Methods and results: Here, we show that the cytotoxic action of genistein against breast cancer cells involves mobilization of endogenous copper. Further, whereas the copper specific chelator neocuproine is able to inhibit the apoptotic potential of genistein, the molecules which specifically bind iron (desferroxamine mesylate) and zinc (histidine) are relatively ineffective in causing such inhibition. Also, genistein‐induced apoptosis in these cells is inhibited by scavengers of reactive oxygen species (ROS) implicating ROS as effector elements leading to cell death. Conclusions: As copper levels are known to be considerably elevated in almost all types of cancers, in this proof‐of‐concept study we show that genistein is able to target endogenous copper leading to prooxidant signaling and consequent cell death. We believe that such a mechanism explains the anticancer effect of genistein as also its preferential cytotoxicity towards cancer cells. 相似文献
204.
Sahar Noori Andleeb Zehra Naqvi Wajid Husain Ansari Mohd Akram Kabir-ud-Din 《Journal of surfactants and detergents》2014,17(3):409-417
Three counterion coupled gemini (cocogem) surfactants in the series 1,6‐bis(N,N‐alkyldimethylammonium) adipate, referred as n‐6‐n (n = 12, 14, 16), were synthesized, purified and characterized by 1H NMR and 13C NMR. Their physicochemical properties were investigated by electrical conductivity and surface tension measurements. The degree of ionization, critical micelle concentration (CMC), surface excess at the air/solution interface (Γmax), minimum area per surfactant molecule at the air/solution interface (Amin), surface tension at the CMC (γCMC), and pC20 (negative log of the surfactant molar concentration, required to reduce the surface tension of water by 20 mN m?1) were calculated. Increase in tail length of the surfactants increases the efficiency of surfactants to decrease the surface tension of water. Thermodynamic parameters, viz. molar free energy at the maximum adsorption attained at CMC (Gmin), standard Gibb's energy of micellization (), and standard Gibbs energy of adsorption (), were also calculated. The and values show that the monomers were preferred to be adsorbed at the air/water interface and then in the micellar formation in the bulk. Additionally, fluorescence measurements were used to find the aggregation number. Other relevant surface properties (Krafft point, emulsion stability, foaming ability, micellar stability and dye solubilization ability) were also evaluated. These results suggest that with respect to emulsion formation, micellar stability and dye solubilization, the cocogem with a 16‐carbon chain gives better results, producing 89 % more stable foams and shows better aggregational behavior. 相似文献
205.
Jagtap R. M. Pardeshi S. K. Nabi Aiman Hussain Zakir Mir Sajjad Husain Rizvi Masood Ahmad 《Microsystem Technologies》2021,27(4):1133-1143
Microsystem Technologies - A target synthesis of selected biocompatible chiral Thiazolidine-4-carboxylic acid derivatives was attempted to investigate the influence of number, type and position of... 相似文献
206.
Rehan Maaz Hasbullah Halabi Faye Ibrahima Rehan Waqas Chughtai Omer Rehmani Mubashir Husain 《Wireless Networks》2019,25(2):915-915
Wireless Networks - The original version of this article contained an error in co-author’s affiliation. The correct affiliation of Dr. Waqas Rehan is given in this erratum. 相似文献
207.
Rashmi Rao Amjad Husain Alok C. Bharti Manoj K. Kashyap 《Proteomics. Clinical applications》2019,13(4)
The renin–angiotensin system (RAS) plays a central role in the regulation of homeostasis and blood pressure. This involves an important enzyme called angiotensin‐converting enzyme that leads to the conversion of angiotensin I into angiotensin II. RAS has been reported to show association with inflammation, and in sporadic studies, with cancer. In particular, angiotensin II has been reported to be prevalent in the hypoxic microenvironment and associated with cancer signaling pathways. In a recent study, Bratlie et al. (Proteomics Clin. Appl. 2019 , 4, 1800102) is shown to exploit 2D gel electrophoresis, and mass spectrometry (MS) to identify differentially expressed proteins by comparing low‐grade dysplasia in Barrett's Esophagus (BE) following administration of agents that interfere with RAS, that is, enalapril and candesartan, and identified specific modulation of HSP60, PDIA3, and PPA1. Though 2D gel coupled with MS is a commonly‐used tool for studying proteomes, it still has limitations in terms of a comprehensive analysis due to lack of absolute quantitation in a high‐throughput manner. Despite technical limitations and the small size of the study, preliminary data emerging from the investigation show interference caused by clinically approved RAS inhibitors resulting in alteration of molecular markers associated with tumorigenicity. The authors propose potential factors that may influence the progression of the disease. However, these are conspicuous changes in high‐abundance proteins only. Therefore, there is a need to carry out detailed experimental studies either using an in vitro labeling technique (isobaric labeling for relative and absolute quantitation) for tissues or an in vivo labeling technique (stable isotope labeling in animal cell culture) coupled with LC‐MS/MS to identify differentially‐regulated proteins to delineate the role of RAS in BE. 相似文献
208.
Raza Mohammad Moeen Hasan Aalam Shah Masheerul Sadiq Mohd Sarvar Mohd Zulfequar Mohammad Husain Samina Ali Javid 《Journal of Materials Science: Materials in Electronics》2022,33(3):1211-1227
Journal of Materials Science: Materials in Electronics - Vertically aligned carbon nanotubes having the advanced atomic configuration, structural properties, and electronic conductivity, which... 相似文献
209.
Electroosmotically enhanced microchannel heat sinks 总被引:1,自引:0,他引:1
The present study investigates the microchannel heat sink for pure electroosmotic, pressure-driven, and mixed (electroosmotic
and pressure-driven) flows. A three-dimensional numerical analysis is performed for electroosmotic and mixed flows. Electroosmotic
flow (EOF) induced in an ionic solution in the presence of surface charge and electric field is investigated with hydrodynamic
pressure-driven flow (PDF) to enhance heat removal through the microchannel heat sink. In a pressure-driven microchannel heat
sink, the application of an external electric field increases the flow rate that consequently reduces the thermal resistance.
The effects of ionic concentration represented by the zeta potential and Debye thickness are studied with the various steps
of externally applied electric potential. A higher value of zeta potential leads to higher flow rate and lower thermal resistance,
which consequently reduce the temperature of the microprocessor chip and load of the micropump used to supply coolant to the
microchannels.
This paper was recommended for publication in revised form by Associate Editor Do Hyung Lee
Afzal Husain received B.E. and M.Tech. degrees in Mechanical Engineering with specialization in Thermal Sciences from Aligarh Muslim University,
India in 2003 and 2005, respectively. Currently he is pursuing Ph.D. degree in Thermodynamics and Fluid Mechanics in Inha
University, Republic of Korea. His research interests are numerical analysis and optimization of heat transfer systems using
computational fluid dynamics and surrogate models, development of heat transfer augmentation techniques for conventional and
micro systems, thermal analysis of microelectromechanical systems (MEMS), and electronic cooling.
Kwang-Yong Kim received a B.S. degree from Seoul National University in 1978, and his M.S. and Ph.D. degrees from Korea Advanced Institute
of Science and Technology (KAIST), Korea, in 1981 and 1987, respectively. Presently, he is professor and chairman, School
of Mechanical Engineering, Inha University, Incheon, Korea. Prof. Kim is presently the editor-in-chief of Transactions of
Korean Society of Mechanical Engineers (KSME), the editor-in-chief of International Journal of Fluid Machinery and Systems
(IJFMS), and chief vice president of Korean Fluid Machinery Association (KFMA). Prof. Kim is Fellow of American Society of
Mechanical Engineers (ASME). 相似文献
210.
Shiva Kumar Singh M. Husain V. P. S. Awana 《Journal of Superconductivity and Novel Magnetism》2012,25(6):1701-1706
Here we study the effect of Ca doping on the charge-transfer mechanism of polycrystalline YBa2Cu3O7??? compound. The samples of composition Y1?x Ca x Ba2Cu3O7??? (x=0.00,0.05,0.10,0.20 and 0.30) are synthesized through standard solid-state reaction route. Carrier doping is controlled by annealing of samples in oxygen and subsequently in reducing atmosphere. Samples are investigated using resistivity, dc magnetization (M?CT) and magnetization with field (M?CH) measurements. With increase of Ca the transition temperature (T c) decreases in oxygenated samples, whereas the same increases in reduced samples. Further reduction of samples at higher temperatures (>600?°C) though results in non-superconducting nature up to Ca concentration of x=0.20, the x=0.30 sample is superconducting below 30?K. This provides a remarkably simple and effective way to study the relationship between structure, superconductivity, and associated electronic properties. Variation in Cu1?CO4, Cu2?CO4 and Cu2?CO2 bond lengths with oxygen content, is seen through the structural refinement of XRD pattern. The effective coordination of Cu2 atom with oxygen changes with the change in these bond lengths and hence the holes in the CuO2 planes. The charge-transfer mechanism from CuO x chains to CuO2 planes and thus effective hole doping is discussed in the context of the results observed. 相似文献