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Mysteries of R^ik=0： A novel paradigm in Einstein＇s theory of gravitation

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Frontiers of physics 2014年第1期9卷 98-112页

作者： ram gopal vishwakarma Unidad Academica de Matemdticas Universidad Autdnoma de Zacatecas C.P. 98068 Zacatecas ZAC Mexico

Despite a century-long effort, a proper energy-stress tensor of the gravitational field, could not have been discovered. Furthermore, it has been discovered recently that the standard formulation of the energy-stress tensor of matter, suffers from various inconsistencies and paradoxes, concluding that the tensor is not consistent with the geometric formulation of gravitation [Astrophys. Space Sci., 2009, 321： 151; Astrophys. Space Sei., 2012, 340： 373]. This perhaps hints that a consistent theory of gravitation should not have any bearing on the energy-stress tensor. It is shown here that the so-called ＂vacuum＂ field equations Rik = 0 do not represent an empty spacetime, and the energy, momenta and angular momenta of the gravitational and the matter fields are revealed through the geometry, without including any formulation thereof in the field equations. Though, this novel discovery appears baffling and orthogonal to the usual understanding, is consistent with the observations at all scales, without requiring the Moreover, the resulting theory circumvents the besides explaining some unexplained puzzles. hypothetical dark matter, dark energy or inflation long-standing problems of the standard cosmology

关键词： general relativity and gravitation - fundamental problems and general formalism cos-mological observations

A critique of supernova data analysis in cosmology

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Research in Astronomy and Astrophysics 2010年第12期10卷 1195-1198页

作者： ram gopal vishwakarma Jayant V. Narlikar Unidad Académica de Matemáticas Universidad Autónoma de Zacatecas Inter-University Centre for Astronomy and Astrophysics

Observational astronomy has shown significant growth over the last decade and has made important contributions to cosmology. A major paradigm shift in cosmology was brought about by observations of Type Ia supernovae. The notion that the universe is accelerating has led to several theoretical challenges. Unfortunately, although high-quality supernovae data-sets are being produced, their statistical anal- ysis leaves much to be desired. Instead of using the data to directly test the model, several studies seem to concentrate on assuming the model to be correct and limiting themselves to estimating model parameters and internal errors. As shown here, the important purpose of testing a cosmological theory is thereby vitiated.

关键词： cosmology: observations -- supernovae Ia: general

Lumped parameter analytic modeling and behavioral simulation of a 3-DOF MEMS gyro-accelerometer

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Acta Mechanica Sinica 2015年第6期31卷 910-919页

作者： Payal Verma Sandeep K.Arya ram gopal MEMS & Micro-sensors Group CSIR – Central Electronics Engineering Research Institute Department of Electronics & Communication Engineering Guru Jambheshwar University of Science & Technology

A new analytical model of a 3-degree-of-freedom （3-DOF） gyro-accelerometer system consisting of a 1-DOF drive and 2-DOF sense modes is presented. The model constructs lumped differential equations associated with each DOFof the system by vector analysis. The coupled differential equations thus established are solved analytically for their responses in both the time and frequency domains. Considering these frequency response equations, novel device design concepts are derived by forcing the sense phase to zero, which leads to a certain relationship between the structural frequencies, thereby causing minimization of the damping effect on the performance of the system. Furthermore, the feasibility of the present gyro-accelerometer structure is studied using a unique discriminatory scheme for the detection of both gyro action and linear acceleration at their events. This scheme combines the formulated settled transient solution of the gyro-accelerometer with the processes of synchronous demodulation and filtration, which leads to the in-phase and quadrature components of the system＇s output signal. These two components can be utilized in the detection of angular motion and linear acceleration. The obtained analytical results are validated by simulation in a MATLAB/Simulink environment, and it is found that the results are in excellent agreement with each other.

关键词： Microelectromechanical systems (MEMS) ·Multimeasurement system. Gyro-accelerometer Gyro-accelerometer model - Transient model

Micropropagation protocol for Salvadora oleoides

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Journal of Forestry Research 2019年第1期30卷 87-93页

作者： Ravindra Kumar Raoof Ahmad Najar Kunj Bihari Gupta ram gopal Saini Department of Biochemistry and Microbial Sciences School of Basic and Applied Sciences Central University of Punjab Department of Plant Sciences School of Basic and Applied Sciences Central University of Punjab Centre for Interdisciplinary Biomedical Research Adesh University

Salvadora oleoides Decne. is a pharmaceutically important plant. Owing to poor seed formation, viability and, germination, and to anthropogenic disturbances, this species is on the verge of extinction. A reproducible micropropagation protocol to increase the population through tissue culture has been standardized and the results are reported here. Callus tissues were initiated from young leaves and stem explants. Leaf calluses proliferated with 1.5 mg/L BAP and 0.9 mg/L 2, 4-D with additives and continuous slow proliferation up to 15 weeks on 0.5 mg/L BAP and additives with 200 mg/L activated *** shoot initiation took place from stem node explants after 12 days; 4–5 shoots per node were produced in 30 days. Shoot clumps elongated and grew further on MS media supplemented with 2 mg/L BAP, 0.2 mg/L NAA and additives, which generated 20–23 shoots. The elongated shoots induced tap roots with 4 mg/L NAA and200 mg/L activated charcoal in 12 days. In vitro raised plants produced secondary roots when transferred to pots containing vermiculite maintained at 28–35 ℃. The plantlets successfully acclimatised in pots containing soil in natural conditions.

关键词： Salvadora oleoides Endangered species Micropropagation Explants Calluses Acclimatize

Ultrasonically Assisted Synthesis of Aromatic Sulfonic Acids under Vilsmeier Haack Conditions in Acetonitrile Medium

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International Journal of Organic Chemistry 2012年第4期2卷 336-340页

作者： Kamatala Chinna Rajanna Purugula Venkanna Mukka Satish Kumar Soma ram gopal Department of Chemistry Osmania University Hyderabad India

Sulfonation of aromatic compounds (Phenols, Anilines) is triggered by Vilsmeier Haack (VH) reagent (DMF/POCl3) or (DMF/SOCl2) in the presence of NaHSO3 under Sonication and conventional stirred conditions at room temperature. The reactions afforded corresponding Sulfonic acid derivatives in very good yields. The results obtained under Sonication were enhanced when compared with the yields of the conventional method.

关键词： Vilsmeier Haack (VH) Reagent Sulfonation NaHSO3 Sonication Aromatic Compounds

Soil and water conservation measures improve soil carbon sequestration and soil quality under cashews

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International Journal of Sediment Research 2021年第2期36卷 190-206页

作者： gopal ramdas Mahajan Bappa Das Sandrasekaran Manivannan Begur Lakshminarasimha Manjunath ram Ratan Verma Sujeet Desai Rahul Mukund Kulkarni Ashish Marotrao Latar Reshma Sale Dayesh Murgaonkar Kiran Puna Patel Shaiesh Morajkar Ashwini Desai Natasha Barnes Heena Mulla Natural Resource Management ICAR-Central Coastal Agricultural Research Institute ICAR-Indian Institute of Soil and Water Conservation Regional Centre Division of Fruit Crops ICAR-Indian Institute of Horticultural Research Division of Crop Production Indian Institute of Sugarcane Research Institute of Agricultural Sciences Banaras Hindu University Biological Oceanography Division CSIReNational Institute of Oceanography Goa University

Land degradation is becoming a serious problem in the west coast region of India where one of the world’s eight biodiversity hotspots, the ‘Western Ghats’, is present. Poor land management practices and high rainfall have led to increasing problems associated with land degradation. A long-term(13-year)experiment was done to evaluate the impact of soil and water conservation measures on soil carbon sequestration and soil quality at three different depths under cashew nut cultivation on a 19% slope. Five soil and water conservation measures-continuous contour trenches, staggered contour trenches, halfmoon terraces, semi-elliptical trenches, and graded trenches all with vegetative barriers of Stylosanthes scabra and Vetiveria zizanoides and control were evaluated for their influence on soil properties,carbon sequestration, and soil quality under cashews. The soil and water conservation measures improved significantly the soil organic carbon, soil organic carbon stock, carbon sequestration rate and microbial activity compared to the control condition(without any measures). Among the measures tested, continuous contour trenches with vegetative barriers outperformed the others with respect to soil organic carbon stock, sequestration rate, and microbial activity. The lower metabolic quotient with the measures compared to the control indicated alleviation of environmental stress on microbes. Using principal component analysis and a correlation matrix, a minimum dataset was identified as the soil available nitrogen, bulk density, basal soil respiration, soil p H, acid phosphatase activity, and soil available boron and these were the most important soil properties controlling the soil quality. Four soil quality indices using two summation methods(additive and weighted) and two scoring methods(linear and non-linear) were developed using the minimum dataset. A linear weighted soil quality index was able to statistically differentiate the effect of soil and water conservation me

关键词： Land degradation Microbial activity Microbial biomass carbon Minimum dataset Soil erosion Western Ghats

Shifting paradigm in brain abscess management at tertiary care centre in Nepal

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Neuroimmunology and Neuroinflammation 2018年第6期5卷 10-17页

作者： Prakash Kafle Mohan Raj Sharma Sushil Krishna Shilpakar gopal Sedain Amit Pradhanang ram Kumar Shrestha Binod Raj Bhandari Christine Groves Department of Neurosurgery Nobel Medical College Teaching HospitalBiratnagar56613Nepal Department of Neurosurgery Tribhuvan University Teaching HospitalKathmandu44613Nepal Department of Physical Medicine and Rehabilitation Indiana University School of MedicineIndianapolisIN46202USA

Aim: Brain abscess is a challenging clinical entity with substantial high case fatality rates despite significant advances in imaging techniques,laboratory modalities,surgical interventions,and antimicrobial *** and cardiogenic sources are among the most *** clinical presentation is seen in very few cases *** hole with aspiration works well with good clinical *** of primary source in cases of ear infection in the single setting results in good outcomes,reduces for additional surgery,and decreases the duration of hospital ***: This is prospective observational study conducted at Institute of Medicine,Tribhuvan University Teaching Hospital,Kathmandu,Nepal over the period of two and a half years(from September 2014 to March 2017).We analyzed the demographic profile,management strategies and outcome of these cases diagnosed with brain abscess using Microsoft Excel ***: A total of 51 cases were undertaken for surgical *** were 35 males and 16 females with the male to female ratio of 2.18:*** mean age of the study population was 16.76 years with age range from 4 months to 60 *** source was the most *** lobe was the most common abscess *** was the most common clinical presentation and was seen in 86.27%of the study *** cases were initially managed with burrhole and aspiration of the *** 3.92%(n = 2)of cases subsequently required surgical excision of the abscess *** 11.76%(n = 6)of the cases required multiple *** 19.61%(n = 10)showed positive *** aeruginosa and *** were the most common organisms *** rate among the study group was 3.92%.Conclusion: With the advent of modern technology in neuroimaging,mortality due to brain abscess has significantly *** involvement of the otorhinolaryngology team and efforts in addressing the primary source have further helped in improving outcomes i

关键词： Abscess otogenic brain abscess tubercular abscess

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金属钛夹联合尼龙绳在内镜治疗术中的应用

长江大学学报（自科版）（下旬） 2016年第4期13卷 11-13,70页

作者： ram gopal Nemkul 胡帝邹传鑫长江大学第二临床医学院荆州市中心医院消化内科湖北荆州434020

目的：探讨金属钛夹联合尼龙绳在消化内镜各种操作中的应用价值。方法：对医院2014年6月至2015年6月间23例不同类型消化道疾病联合应用金属钛夹和尼龙绳进行内镜下治疗的效果进行回顾性分析。结果：23例患者中上消化道病变3例（13.0%）... 详细信息

目的：探讨金属钛夹联合尼龙绳在消化内镜各种操作中的应用价值。方法：对医院2014年6月至2015年6月间23例不同类型消化道疾病联合应用金属钛夹和尼龙绳进行内镜下治疗的效果进行回顾性分析。结果：23例患者中上消化道病变3例（13.0%）,结肠病变20例（87.0%）。其中内镜下应用金属钛夹联合尼龙绳结扎进行息肉切除22例（95.7%）,内镜下尼龙绳结扎联合金属钛夹荷包缝合内镜下粘膜下剥离术中穿孔创面1例（4.3%）。所有患者术后均未见迟发出血及穿孔表现。术后1~3月内复查,所有患者均未见尼龙绳及金属钛夹残留。结论：金属钛夹联合尼龙绳结扎在治疗和预防各种临床内镜操作中出血及穿孔的疗效肯定。

关键词：消化系统疾病金属钛夹尼龙绳内镜下治疗出血穿孔