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THE EFFECT OF MAGNETIC FIELDS ON LOW FREQUENCY OSCILLATING NATURAL CONVECTION WITH PRESSURE GRADIENT

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Applied Mathematics and Mechanics(English Edition) 2003年第3期24卷 274-283页

作者： G.C.Sharma madhu jain Mahesh Chandra School of Mathematical Sciences Institute of Basic ScienceSchool of Mathematical SciencesInstitute of Basic ScienceSchool of Mathematical SciencesInstitute of Basic Science KhandariAgra-282002IndiaKhandariAgra-282002IndiaKhandariAgra-282002India

The oscillating natural convection in the presence of transverse magnetic field with time depending pressure gradient is studied. The analysis of the problem is carried out by assuming that the fluid is flowing in a parallel plate configuration. The emphasis is on low frequency oscillating convective flows induced by g-jitter associated with micro gravity because of their importance to the space processing materials. A general solution for an oscillating flow in the presence of transverse magnetic field is carried out. Some special cases of the oscillating flow and its response to an applied magnetic field are performed. It was observed that the behavior of oscillating free convective flows depends on frequency, amplitude of the driving buoyancy forces, temperature gradient,magnetic field and the electric conditions of the channel walls. In the absence of magnetic field, buoyancy force plays a predominant role in driving the oscillatory flow pattern, and velocity magnitude is also affected by temperature gradients. To suppress the oscillating flow external magnetic field can be used. It is also found that the reduction of the velocity is inversely proportional to the square of the applied magnetic field with conducting wall but directly proportional to the inverse of the magnetic field with insulating wall. Detailed calculations and computational results are also carried out to depict the real situation.

关键词： convection g- jitter acceleration buoyancy force magnetic field pressure gradient

An association between maternal lead and cadmium levels and birth weight of the babies in North Indian population

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Open Journal of Obstetrics and Gynecology 2013年第3期3卷 331-336页

作者： Divya Dwivedi madhu jain Shuchi jain Department of Obstetrics & Gynaecology Institute of Medical Sciences Banaras Hindu University Varanasi India

Lead is listed as the 2nd and Cadmium as the 7th hazardous substance by the Agency for Toxic Substances and Disease Registry (ATSDR). Exposure to Lead and Cadmium above the permissible levels among pregnants may cause adverse effects on newborns in the form of Low Birth Weight and Preterm Labor, etc. The objectives of this study were to find out the level of Lead and Cadmium in maternal venous blood and cord blood and to find out the association of the levels of these metals with birth weight of babies. For this, the venous blood and cord blood were collected and quantitative estimation of Lead and Cadmium was carried out by Double Beam Atomic Absorption Spectrophotometer in 1000 women with average Body Mass Index. Results showed higher mean maternal blood Lead level (11.08 μg/dl with range of 2.6 - 21.3) than the normal recommended by Centre of Disease Control and Prevention (10 μg/dl). On the contrary, the mean Cadmium level was 0.095 μg/dl, which was below the normal value as assigned by WHO (0.1 μg/dl). In high Lead exposure group (>10 μg/dl), 43.7% of babies and in high Cadmium exposure group (>0.1 μg/dl), 46.2% of babies were found to have low birth weight. However, this was not statistically significant. Further research in this area in a larger sample size may provide information relevant enough to be transferred to decision makers to implement measures to effectively reduce heavy metals from the environment, thereby protecting future generations from their deleterious effects.

关键词： Lead Cadmium Environmental Exposure Birth Weight Venous Blood Cord Blood

An unusual case of ovarian torsion with infarction simulating malignancy in an adolescent girl

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Open Journal of Obstetrics and Gynecology 2011年第3期1卷 124-127页

作者： madhu jain Kusum Lata Shivi jain 不详

Torsion of the ovary is an uncommon condition. It is the 5th most common gynaecological emergency. It most commonly occur in reproductive age group, on right side, often in presence of congenital abnormalities of adnexa but may occur in their absence too. Adnexal torsion often poses a diagnostic challenge because of non specific symptoms of presentation. Ultrasound with colour Doppler may be helpful.

关键词： Adenexal Torsion Ovarian Infarction Colour Doppler

Diagnostic Accuracy of Sonosalpingography for Assessing Tubal Pathology in Women with Secondary Infertility Taking Laparoscopy as Gold Standard

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Surgical Science 2012年第8期3卷 414-417页

作者： Amit Nandan Dhar Dwivedi madhu jain Suchi Tripathi Sunny Garg Shivi jain Institute of Medical Sciences: BHU Varanasi. India

Context: Secondary infertility is a major public health issue with growing urbanisation and increasing age of marriage among women. Disease limited to low socioeconomic strata is commonly seen in general population. Judicious and accurate assessment of underlying pathology targeting tubes should be undertaken. Aims: The aim of this observational study was to assess the diagnostic accuracy of sonosalpingography taking laparoscopy as gold standard in patients of secondary infertility. Main aim was to assess tubal factors as an underlying cause and to assess feasibility of a radiation free protocol in patients of reproductive age group. Settings and Design: The study was carried out in a hospital setting. A total of 123 patients were selected. Patients of primary infertility were excluded. Sonosalpingography was performed by a single experienced radiologist. This was confirmed by laparoscopy conducted by an experienced gynaecologist. Methods and Material: A detailed clinical and physical examination including internal examination was done. This was followed by sonosalpingography using high frequency TVS probe (Philips IU 22). All patients were subjected to laparoscopic evaluation on the same day. Statistical analysis: Sensitivity, specificity, diagnostic accuracy and predictive values. Results: Sonosalpingography was 72.91% sensitive, 81.33% specific with diagnostic accuracy of 78.05% and positive predictive value of 71.42% for tubal pathologies. Conclusions: Sonosalpingography is a very useful complementary diagnostic modality in assessment of tubal pathology. This should precede direct laparoscopic evaluation. Patients of secondary infertility can be assessed with a combination of sonosalpingography and laparoscopy. This saves the patient of radiation exposure as well as pain of contrast

关键词： Sonosalpingography Secondary Infertility Laparoscopy Chromopertubation

MRI is a state of art imaging modality in characterization of indeterminate adnexal masses

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Journal of Biomedical Science and Engineering 2013年第3期6卷 309-313页

作者： Amit Nandan Dhar Dwivedi Shivi jain Ram Chandra Shukla madhu jain Arvind Srivastava Ashish Verma Department of Obstetrics and Gynecology Institute of Medical Science Varanasi India Department of Radiodiagnosis and Imaging Institute of Medical Science Varanasi India

Aims and Objectives: The aim of this diagnostic observational study was to find an association of final diagnosis of adnexal masses suggested by MRI and compare it as an imaging modality in determining the origin, nature (benign/malignant) & characteristics of adnexal masses by calculating sensitivity, specificity, and diagnostic accuracy. Materials and Methods: The present study was carried out in 90 patients in the department of radio diagnosis and imaging, institute of medical sciences, Banaras Hindu University (BHU). The patients were referred from department of obstetrics & gynecology, institute of medical sciences. Majority of the referred cases were those who had clinical features of abdominal pain, abdominal lump, menstrual irregularity, ascites, and anorexia or weight loss & in whom adnexal mass was suspected clinically. Magnetic resonance imaging was performed using 1.5 Tesla MR Scanner, Magnetom Avanto (Siemens Healthcare). Results: Out of 114 masses, 17 (14.9%) were malignant. The benign adnexal masses were maximum in the age group 20 - 39 years (56/97, 57.7%), while malignant masses were mainly found in women ≥60 years of age (11/17, 64.7%). CA-125 level was grossly elevated in association with 35.3% of the malignant masses. On MRI, the sensitivity for the mass of ovarian origin was (97.7%) and specificity was (73.1%). The diagnostic accuracy was (92.1%). The mass of uterine origin had a sensitivity of (73.1%) and diagnostic accuracy (99.1%). Conclusion: MRI, because of its accuracy in identifying the origin of adnexal mass and characterizing the solid, hemorrhagic, fatty and fibrous content, may obviate surgery or significantly contribute to preoperative planning for a sonographically indeterminate mass. MRI is the state of the art imaging modality for evaluation of adnexal masses with an overall high diagnostic accuracy.

关键词： MRI Adnexal Masses Diagnostic Accuracy

Hot deformation behavior and processing maps of Ti-15Al-12Nb alloy

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Rare Metals 2022年第7期41卷 2316-2323页

作者： Ravindranadh Bobbili Vemuri madhu Defense Metallurgical Research Laboratory Hyderabad 500058India

The isothermal hot compression tests of Ti-15Al-12Nb alloy under wide range of strain rates(0.01-10.00 s^(-1)and deformation temperatures(950,1000,1050,and 1100℃)were carried out using Gleeble-3500 thermo-simulation machine.A constitutive equation represented as a function of temperature,strain rate and true strain was developed,and the hot deformation appar-ent activation energy is calculated to be about 453 kJ·mol^(-1).By employing dynamic material model(DMM),the processing maps of Ti-15Al-12Nb alloy at various strains were *** efficiency of about 57%for power dissipation is obtained at high temperature and low strain *** to the high power dissipation efficiency and excellent processing ability in dynamic recrystallization(DRX)zone for metal material,the optimum processing conditions are selected as the temperature range of 1050-1100℃and the strain rate range of 0.01-0.10 s^(-1).Using transmission electron microscopy(TEM)studies,it is found that the dislocation density is directly associated with the value of processing *** is observed that when the processing effi-ciency is about 22%,the dislocation density is reasonably *** flow instability region occurs at strain rate of 10.00 s^(-1)with cracks,which should be avoided during hot processing to obtain the required mechanical properties.

关键词： Hot deformation Processing map Ti–15Al–12Nb

Antioxidant and modulatory role of Chlorophytum borivilianum against arsenic induced testicular impairment

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Journal of Environmental Sciences 2012年第12期24卷 2159-2165页

作者： Garima Sharma madhu Kumar Cell and Molecular Biology Laboratory Department of ZoologyCentre for Advanced studiesUniversity of RajasthanJaipur 302055India

Arsenic has a suppressive influence on spermatogenesis and induces impairment in male reproductive system due to oxidative stress. The present study was aimed to test the arsenic induced toxicity and protection by Chlorophytum borivilianum. The effect of sodium arsenite （4 mg/（kg body weight （bw）.day）） via double distilled water without or with C. borivilianum （800 mg/（kg ***）） was evaluated in Swiss albino mice for 30 days. The radical scavenging activity of the aqueous C. borivilianum root extract was measured using DPPH （1,1-diphenyl-2-picryl hydrayzyl） radical. Qualitative assessment of various cell types in the testis, sperm count and motility, testicular activity of lipid peroxidation （LPO）, reduced glutathione （GSH）, acid and alkaline phosphatase, cholesterol and serum testosterone were monitored. Arsenic treatment showed a significant increase in LPO, acid and alkaline phosphatase, cholesterol and decrease in sperm count, sperm motility, GSH and serum testosterone. Combined treatment showed significant decrease in LPO, acid and alkaline phosphatase, cholesterol and elevation in sperm count, sperm motility, GSH and serum testosterone. Testicular histopathology showed that C. borivilianum had reduced degeneration of germ cell in the seminiferous tubules and loss of sperms induced by arsenic intoxication. The results thus led us to conclude that administration of C. borivilianum root extract is found to be protective against arsenic induced toxicity.

关键词： DPPH radical assay Chlorophytum borivilianum reduced glutathione lipid peroxidation arsenic testosterone

An efficient approach for anti-jamming in IRNSS receivers using improved PSO based parametric wavelet packet thresholding

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Satellite Navigation 2022年第3期3卷 51-70,I0003页

作者： Jacob Silva Lorraine Kambham madhu Ramarakula Department of ECE University College of EngineeringJNTUKKakinadaAndhra Pradesh533003India

The Indian Regional Navigation Satellite System provides accurate positioning service to the users within and around India,extending up to 1500 ***,when a receiver encounters a Continuous Wave Interference,its positioning accuracy degrades,or sometimes it even fails to *** Packet Transform(WPT)is the most widely used technique for anti-jamming in Global Navigation Satellite System *** the conventional method suffers from threshold drifting and employs inflexible thresholding ***,to address these issues,an efficient approach using Improved Particle Swarm Optimization based Parametric Wavelet Packet Thresholding(IPSO-PWPT)is ***,a new parameter adaptive thresholding function is ***,a new form of inertia weight is presented to enhance the performance of ***,IPSO is used to optimize the key parameters of ***,the implementation of the IPSO-PWPT anti-jamming algorithm is *** performance of the proposed technique is evaluated for various performance metrics in four jamming *** evaluation results manifest the proposed method’s efficacy compared to the conventional WPT in terms of anti-jamming ***,the results show the ability of the new thresholding function to process various signals ***,the findings reveal that the improved PSO outperforms the variants of PSO.

关键词： Continuous wave interference(CWI) IRNSS Particle swarm optimization(PSO) Wavelet packet transform(WPT)

Reliability Enhanced Multi-objective Economic Dispatch Strategy for Hybrid Renewable Energy System with Storage

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Journal of the Operations Research Society of China 2023年第1期11卷 51-81页

作者： Anongpun Man-Im Weerakorn Ongsakul Nimal madhu Department of Energy Environment and Climate ChangeSchool of EnvironmentResources and DevelopmentAsian Institute of TechnologyKlong LuangPathumthani12120Thailand

An optimal dispatch strategy for the economic operation of hybrid renewable energy system with storage is presented in this paper. Solar photovoltaic (PV), Wind and Battery Storage are the prime components of interest constituting the hybrid system. In addition to the economic aspect of the systems, the formulation focuses on renewable prioritized operation, system reliability and environmental sustainability enhancement. Being a multi-objective (MO) problem, a modified non-dominated sorting particle swarm optimization is used for solving the problem, considering operational cost, pollutant emission, and expected energy not served as operational objectives. The non-dominated sorting particle swarm optimization (NSPSO) is augmented with crowding distance technique, stochastic weight trade-off and chaotic mutation approaches, to control the exploration of global and particle bests, alleviating premature convergence, and enhancing solution search capability. A two-stage approach is used to derive the best solution. A modified IEEE 30-bus test system is used to demonstrate the results. By using the proposed approach, a lower and wider Pareto front is obtained, in comparison with prominent optimization approaches.

关键词： Multi-objective economic dispatch Emission reduction Particle swarm optimization Hybrid energy system Expected energy not served Battery energy storage