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Functional significance of erythropoietin receptor on tumor cells

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World Journal of Gastroenterology 2006年第46期12卷 7460-7462页

作者： Kodetthoor B udupa Reynolds Institute on Aging Department of Geriatrics Physiology and Biophysics University of Arkansas for Medical Sciences and Central Arkansas Veterans Healthcare System 4300 West Seventh Street Little Rock AR United States

Erythropoietin (Epo) is the regulator of red blood cell formation. Its receptor (EpoR) is now found in many cells and tissues of the body. EpoR is also shown to occur in tumor cells and Epo enhances the proliferation of these cells through cell signaling. EpoR antagonist can reduce the growth of the tumor in vivo. In view of our current knowledge of Epo, its recombinant forms and receptor, use of Epo in cancer patients to enhance the recovery of hematocrit after chemotherapy treatment has to be carefully evaluated.

关键词： Erythropoietin Tumor cell Receptor Cell signaling Proliferation Erythroid cell

Pressure pulsation in stages of electric submersible pump at shut-off under various speeds

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排灌机械工程学报 2020年第7期38卷 649-657页

作者： DHANASEKARAN Arumugam kumaraswamy Sivasailam Department of Mechanical Engineering Chennai Institute of TechnologyChennaiTamilnadu 600069India Department of Mechanical Engineering Indian Institute of Technology MadrasChennaiTamilnadu 600036India

Electric submersible pumps were widely used in agricultural fields,petroleum and various other industries. The pressure pulsation caused fatigue failure due to vibration in electric submersible pump and affects the life and performance of its system. The objective of this study was to experimentally investigate the characteristics of pressure pulsation which were generated at various stages of a multistage electric submersible pump during closed valve operation at different speeds. An electric submersible pump with five stages was selected for conducting experiments. A variable frequency drive( VFD)was used to operate the electric submersible pump at five different speed settings from 40 to 60 Hz. Piezoresistive pressure transducers were mounted at each stage of the electric submersible pump to capture the unsteady pressure signals. At each speed setting,the electric submersible pump was operated at the shut-off condition and the signals of unsteady pressure from all the five stages were captured. A fast fourier transformation( FFT) was carried out on the pressure signals to convert into frequency *** the spectra of pressure pulsation signals,the characteristics of pressure pulsation are obtained for each stage and for various speed settings which were then used to understand its variation with speed and stages.

关键词： electric submersible pump shut-off stage pressure pulsation variable frequency

Dynamic hesitant fuzzy linguistic group decision-making from a reliability perspective

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1009-1021页

作者： MA Zhenzhen PONNAMBALAM kumaraswamy ZHU Jianjun ZHANG Shitao College of Economics and Management Nanjing University of Aeronautics and Astronautics Department of Systems Design Engineering University of Waterloo School of Mathematics & Physics Science and Engineering Anhui University of Technology

A dynamic hesitant fuzzy linguistic group decisionmaking(DHFLGDM) problem is studied from the perspective of information reliability based on the theory of hesitant fuzzy linguistic term sets(HFLTSs). First, an approach is applied to transform the dynamic HFLTSs(DHFLTSs) into a set of proportional linguistic terms to eliminate the time dimension. Second, expert reliability is measured by considering both group similarity and degree of certainty, and an optimization method is employed to quantify the linguistic terms by maximizing the group similarity. Third, through computing the attribute stability as well as its reliability, a combination rule which considers both reliability and weight is proposed to aggregate the information, and then the aggregated grade values and degree of stability are used to make a selection. Finally,the application and feasibility of the proposed method are verified through a case study and method comparison.

关键词： dynamic decision-making hesitant fuzzy linguistic term sets(HFLTSs) proportional linguistic terms group similarity degree of certainty

Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

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World Journal of Gastroenterology 2006年第46期12卷 7428-7432页

作者： Parimal Chowdhury Kodetthoor B udupa Departments of Physiology and Biophysics University of Arkansas for Medical Sciences 4301 W Markham Street Little Rock Arkansas 72205 United States Departments of Physiology and Biophysics and Geriatrics University of Arkansas for Medical Sciences 4301 W Markham Street Little Rock Arkansas 72205 United StatesMedical Service Central Arkansas Veterans Healthcare System Little Rick Arkansas 72205 United States

Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine, a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems. In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

关键词： Cell Proliferation Nicotine AR42J cells Pancreatic acinar cells ERK activation

Enhancement of seal life through carbon composite back-up rings under shock loading conditions in defence applications

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Defence Technology（防务技术） 2016年第1期12卷 39-45页

作者： Shankar BHAUMIK A.kumaraswamy S.GURUPRASAD R&DE(Engrs.) Pune 411015MaharashtraIndiab defence institute of advanced technology(du) Pune 411025MaharashtraIndia

The life of Nitrile Butadiene Rubber(NBR) O-ring seal having shore hardness of A70 and A90 under shock loading conditions was investigated by a specially designed pneumo-hydraulic shock test rig. Shock tests have been carried out on bare seals, seal with conventional polytetrafluoroethylene(PTFE) back-up rings and seal with newly developed carbon composite back-up rings to study its behaviour under different operating conditions until failure. Experiments were conducted by varying annular gap ranging from 0.3 to 0.5 mm, oil temperature from 30 ℃ to 70 ℃ and rate of pressure rise from 600 to 2400 MPa/s. Significant enhancement in seal life was observed with carbon composite back-up ring at reduced annular clearances compared to seal life with conventional PTFE back-up ring and without back-up rings.

关键词：碳纤维复合材料密封寿命载荷条件冲击试验台压力上升应用国防 O型密封圈

Formation of microstructural features in hot-dip aluminized AISI 321 stainless steel

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 190-198页

作者： Prashant Huilgol K.Rajendra udupa K.Udaya Bhat Department of Metallurgical & Materials Engineering National Institute of Technology Karnataka

Hot-dip aluminizing（HDA） is a proven surface coating technique for improving the oxidation and corrosion resistance of ferrous substrates. Although extensive studies on the HDA of plain carbon steels have been reported, studies on the HDA of stainless steels are limited. Because of the technological importance of stainless steels in high-temperature applications, studies of their microstructural development during HDA are needed. In the present investigation, the HDA of AISI 321 stainless steel was carried out in a pure Al bath. The microstructural features of the coating were studied using scanning electron microscopy and transmission electron microscopy. These studies revealed that the coating consists of two regions： an Al top coat and an aluminide layer at the interface between the steel and Al. The Al top coat was found to consist of intermetallic phases such as Al_7Cr and Al_3Fe dispersed in an Al matrix. Twinning was observed in both the Al_7Cr and the Al_3Fe phases. Furthermore, the aluminide layer comprised a mixture of nanocrystalline Fe_2Al_5, Al_7Cr, and Al. Details of the microstructural features are presented, and their formation mechanisms are discussed.

关键词： hot-dip aluminizing aluminide layer intermetallic phases microstructural features stainless steel

Influence of welding consumables on tensile and impact properties of multi-pass SMAW Armox 500T steel joints vis-a-vis base metal

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Defence Technology（防务技术） 2018年第3期14卷 188-195页

作者： Ambuj Saxena A.kumaraswamy G.Madhusudhan Reddy Vemuri Madhu Defence Institute of Advanced Technology(DU) Pune 411025India Defence Metallurgical Research Laboratory KanchanbaghHyderabad 500048India

In this investigation, comparative study of tensile and impact properties of multi-pass SMAW Armox500 T steel joints fabricated by austenitic stainless steel(ASS) and low hydrogen ferritic steel(LHF)consumables vis-a-vis base metal was carried out. The tensile tests were conducted on computer controlled Walter t Bai Ag UTM at a nominal strain rate of 10à3 sà1. Subsequently, charpy impact tests were carried out on an instrumented Zwick-Roell test setup to obtain load vs. displacement and maximum energy absorbed vs. displacement of the specimen. It was observed that, the joint efficiency of weldment processed by LHF consumable was 41.7% and weldment processed by ASS was 30.6% of its base metal indicating the influence of electrode consumable on tensile properties of the joints. On the contrary, impact toughness of weldment processed by ASS was 20% more and weldment processed by LHF was 12% less than that of base metal. Microstructural studies also revealed that, ASS can be considered as a candidate welding consumable for good strain hardening and toughness of the welding joint in impact applications. However, LHF steel consumable is recommended for welding joints that requires higher joint efficiency under tensile loading conditions.

关键词： SMAW 不锈钢金属相焊接张力关节性质传递

Parametric study of single confined fragment launch explosive device

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Defence Technology（防务技术） 2019年第2期15卷 179-185页

作者： Pankaj K.Choudha A.kumaraswamy Kusumkant D.Dhote Armament Research & Development Establishment (DRDO) Defence Institute of Advanced Technology

In this article, parametric study of single confined fragment launch device was carried out. The configuration proposed was further studied to derive the empirical relationship for effect of fragment size,charge size, confinement thickness on fragment velocity. The simulations were carried out using ANSYSAUTODYNE explicit solver. Fragment velocities were estimated as a function of different parametric combinations of explosive quantities, charge length to diameter ratio, fragment height to diameter ratio,confinement thickness, fragment material and fragment mass. The data was further converted to charge to metal ratio under fragment and confinement. It was observed that, increase in confinement thickness,charge quantity and decrease in fragment height increases the fragment velocity. It is also noted that,charge to metal mass ratio under fragment significantly affects the fragment velocity. At the end, an empirical relationship for fragment velocity interms of all these parameters was established. Using these relations, two velocities 1831.92 m/s and 2523.9 m/s required for NATO STANAG 4496 IM test were estimated. The design parameters for these velocities are presented. Also, the results estimated using the empirical relationship has been compared with published experimental data. Error in the predicted velocities is within the acceptable range. The empirical relationship proposed will be useful for finalization of design of the fragment launch device.

关键词： Confinement Fragment size Empirical relationship Fragment velocity Insensitive munition test Fragment launching device

In vitro analysis on bactericidal screening and antioxidant potentiality of leaf and root extracts of Thottea siliquosa(Lam.)Ding *** ethnobotanical plant

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Asian Pacific Journal of Tropical Biomedicine 2013年第11期3卷 859-865页

作者： Saiba Abdul Wahab Nusaiba kumaraswamy Murugan College of Pharmaceutical Sciences Medical College Plant Biochemistry and Molecular Biology Laboratory Department of BotanyUniversity College

Objective:Natural products of plant origin are potential source of novel antimicrobial and antioxidative *** siliquosa(Lam.)Ding Hou.(***).A medicinal herb used by local tribals for treating various *** present study aims at the phytochemical screening,GC-MS analysis,in vitro antibacterial activity and antioxidant potentiality of root and leaf extracts of ***:Hot continuous Soxhlct extraction,GC-MS analysis,antibacterial analysis by disc diffusion,microdilution assay and antioxidant potentialities by hydroxyl radical and nitric oxide radical *** data was statistically ***:Phytochemical screening of the ethyl acetate and methanolic extract of leaf and root revealed the presence of phenols,alkaloids,tannins and *** extract revealed a pool of phytochemicals by comparison with authentic standards from spectral *** the extracts has shown their broad spectrum of inhibition against the selected bacteria Staphylococcus aureus,Escherichia coli,Pseudomonas aeruginosa and Klebsiella pneumonia compared with standard antibiotic drug *** extracts showed antioxidant activity by scavenging of free radicals such as hydroxyl and nitric *** IC_(50)values of the ethyl acetate extracts leaf and root and standard in this assay were I67.5±0.67,99.4±1.2,192±2.5μg/mL *** those methanolic extracts of leaf and root were 269.5±0.89 and 289.1±2.66μg/mL ***,ethyl acetate and methanolic extracts also caused a moderate dose-dependent inhibition of nitric oxide with an IC_(50)range 65.5±1.55 to 148±3.09μg/*** inhibitory activities were found to be dose ***:The present study provides evidence that ethyl acetate and methanol extract of leaf and root of *** are potential source of natural antioxidants and bactericidal *** is essential that research should continue to isolate and purify the bio active components of this natural p

关键词： Antibacterial activity Antioxidant potentiality Phytochemicals Soxhlet extraction Thottea siliquosa