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Search Results: 1 - 10 of 223806 matches for " R. Ramanna "
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Time-delay, energy-continuum, and systematics of particles
S. R. Jain,R. Ramanna,K. Ramachandra
Physics , 2003,
Abstract: Finding systematics in the mass-lifetime data for all the hadrons has been an outstanding problem. In this work, we show that the product of mass and lifetime for unstable particles is very well-approximated by \hbar 2^n/n where n is an integer specific for a particle. In doing so, we have employed a relation between time-delay and resonances. The energy-continuum has been treated in a way to take advantage of Cantor's mathematical work on continuum. Thus, even though the resonances are designated by complex energy variables where ordering is not possible, in terms of stability, the index n labels these resonances; larger the n, more stable a resonance is.
Quantum Limit on Computational Time and Speed
A. K. Pati,S. R. Jain,A. Mitra,R. Ramanna
Physics , 2002, DOI: 10.1016/S0375-9601(02)01041-1
Abstract: We investigate if physical laws can impose limit on computational time and speed of a quantum computer built from elementary particles. We show that the product of the speed and the running time of a quantum computer is limited by the type of fundamental interactions present inside the system. This will help us to decide as to what type of interaction should be allowed in building quantum computers in achieving the desired speed.
The Prediction of the Maximum Modes of Decay of Mesons
Raja Ramanna
Physics , 1999,
Abstract: In an earlier work, several properties of fundamental particles were brought together by a simple equation based on continuity and discreteness. It is shown here, that the maximum modes of decay of all fundamental particles can also be predicted without any arbitrary parameters. The method used is to break up the mean lifetimes of particles to obtain the maximum modes of decay. This is done by using a binary expansion of $\hbar/MT$ where M is the mass of the particle and T is the mean lifetime. The agreements between that obtained from theory and experiment are remarkable. The ordering of the flavours plays an important part in understanding the reasons for this agreement. It is shown that the Zeno effect in Quantum mechanics is connected with use of the binary series.
The Systematics of Fundamental Particles and Unstable Nuclear Systems Using the Concept of Continuity and Discreteness
Raja Ramanna,Anju Sharma
Physics , 1997,
Abstract: In this review, a new method is proposed based on Cantor's theory of Cardinality to analyze the experimental data on unstable nuclear systems which includes fundamental particles and their flavours, $\beta$-decay including spin and parity, $\alpha$-decay and the systematics of the energy levels of light nuclei. The method also derives a formula for the Binding Energies of unstable nuclei. All this is based on the theory of discreteness and continuity.
Abnormal coronary artery angiography is not associated with adverse pregnancies outcomes  [PDF]
Margriet A. M. Heemskerk, Hemanth Ramanna, Kitty W. M. Bloemenkamp, Christianne J. M. de Groot
Open Journal of Obstetrics and Gynecology (OJOG) , 2012, DOI: 10.4236/ojog.2012.21012
Abstract: Background: Recently, epidemiologic studies have suggested an association between pregnancy complications and the development of coronary artery disease later in life. The current study investigate the relation between obstructive coronary versus normal coronary angiographies and the prevalence of complications during pregnancy including preeclampsia, pregnancy induced-hypertension, low birth weight, and preterm birth. Methods: All consecutive women aged <55 year, who had coronary angiography were included. Based on angiography outcome, patients were classified as normal (controls: no stenosis, wall irregularity without stenosis, or minimal calcification present) or abnormal (subjects). A standard questionnaire was sent to all participating women. The questionnaires inquired into risk factors for coronary vascular disease, in particular history of hypertensive diseases, and specific obstetric history. The results were analyzed using the unpaired t-test, the Chi-squared test, and Pearson’s correlation coefficients as appropriate. A significance level of P < 0.05 was used. Results: Of the 211 consecutive women aged <55 year, 62% (n = 131) had normal coronary angiography and 38% (n = 80) abnormal coronary angiography. We found no differences of reported pregnancy complications including preeclampsia, hypertension, low birth weight, and preterm birth (combined RR = 0.70, 95% C.I. = 0.38 - 1.3) in case of abnormal coronary angiography compared to women with normal coronary angiography. The traditional risk factors hypercholesterolemia, tobacco use, and diabetes were identified as the major risk factors for developing cardiovascular disease, with a relative risk ranging from 4.2 - 1.8. Conclusion: These data suggest that pregnancy complications are not an important denominator for cardiovascular disease.
Biventricular Noncompaction Cardiomyopathy in a Patient Presenting with New Onset Seizure: Case Report
Oghenerukevwe Odiete,Ramanna Nagendra,Mark A. Lawson,Henry Okafor
Case Reports in Cardiology , 2012, DOI: 10.1155/2012/924865
Abstract: Ventricular noncompaction (VNC) of the myocardium is a rare genetic cardiomyopathy caused by a disorder during endocardial morphogenesis and could be accompanied by life-threatening complications. The major clinical manifestations of VNC are heart failure, arrhythmias, and embolic events. The left ventricle is the most commonly reported affected site, but a few cases of right ventricular involvement have also been reported. We report a case of biventricular noncompaction cardiomyopathy in a 31-year-old woman presenting with a new onset seizure. On the second day of her telemetry-monitored hospitalization, she suffered a witnessed ventricular fibrillation arrest requiring emergency direct-current cardioversion and induced hypothermia. Transthoracic echocardiography (TTE) showed isolated left ventricular (LV) noncompaction and depressed LV systolic function. Subsequent cardiac magnetic resonance imaging (MRI) revealed both left and right ventricular noncompaction. This unusual presentation highlights the importance of a complete and thorough evaluation of patients even when presenting with apparently noncardiac symptom(s).
Technical note: Image guided internal fiducial placement for stereotactic radiosurgery (CyberKnife)
Mallarajapatna Govindarajan,Susheela Sridhar,Kallur Kumar,Ramanna Nagaraj
Indian Journal of Radiology and Imaging , 2011,
Abstract: Internal gold fiducials are necessary for tracking the translational and rotational movements of target lesions during stereotactic radiosurgery. The fiducials are generally placed under image guidance in and around the lesions by interventional radiologists. Specific challenges are encountered during the procedure. This article discusses the basic principles and techniques as well as the specific complications.
Biventricular Noncompaction Cardiomyopathy in a Patient Presenting with New Onset Seizure: Case Report
Oghenerukevwe Odiete,Ramanna Nagendra,Mark A. Lawson,Henry Okafor
Case Reports in Cardiology , 2012, DOI: 10.1155/2012/924865
Abstract: Ventricular noncompaction (VNC) of the myocardium is a rare genetic cardiomyopathy caused by a disorder during endocardial morphogenesis and could be accompanied by life-threatening complications. The major clinical manifestations of VNC are heart failure, arrhythmias, and embolic events. The left ventricle is the most commonly reported affected site, but a few cases of right ventricular involvement have also been reported. We report a case of biventricular noncompaction cardiomyopathy in a 31-year-old woman presenting with a new onset seizure. On the second day of her telemetry-monitored hospitalization, she suffered a witnessed ventricular fibrillation arrest requiring emergency direct-current cardioversion and induced hypothermia. Transthoracic echocardiography (TTE) showed isolated left ventricular (LV) noncompaction and depressed LV systolic function. Subsequent cardiac magnetic resonance imaging (MRI) revealed both left and right ventricular noncompaction. This unusual presentation highlights the importance of a complete and thorough evaluation of patients even when presenting with apparently noncardiac symptom(s). 1. Introduction Ventricular noncompaction (VNC) of the myocardium is a rare genetic cardiomyopathy that is believed to arise from arrested endomyocardial development during embryogenesis [1]. It is a rare idiopathic cardiomyopathy with an incidence of about 0.05% [2, 3]. VNC is classified by the American Heart Association as a primary genetic cardiomyopathy [1] and is characterized by an altered myocardial wall with prominent trabeculae and deep intertrabecular recesses. This results a thickened bilayer of compacted and noncompacted myocardium [4], caused by the arrest of the normal process of endomyocardial morphogenesis. The normal process of trabeculation has been shown to be dependent upon secretion of neuregulin growth factors from the endocardium. Angiogenic factors, such as vascular endothelial growth factor and angiopoietin-1, may also be critical for normal trabeculae formation [5, 6]. The major clinical manifestations of VNC are heart failure, arrhythmias, sudden cardiac death, cardioembolic events, and syncope [7–9]. To our knowledge, seizures have not been previously reported as a manifestation of this condition. Here, we report a case of biventricular noncompaction cardiomyopathy in a young female presenting with new-onset tonic-clonic seizure. 2. Case Presentation A 31-year-old woman presented with a witnessed loss of consciousness while driving. The episode lasted for about five-to-ten minutes and was associated with
Study of impurity distribution in mechanically polished, chemically treated and high vacuum degassed pure Niobium samples using TOFSIMS technique
A. Bose,S. C. Joshi Raja Ramanna Centre for Advanced Technology
Physics , 2015,
Abstract: The performance of Superconducting radio frequency cavities (SRF) is strongly influenced by various impurities within the penetration depth (~50nm) of Nb, which in turn depends on the applied surface treatments. The effect of these surface treatments on the impurities of Nb has been explored using various surface analytical treatments. But, the results are still inadequate in many aspects and the effect of sequential SRF treatments on the impurity distribution has not been explored. The present study analyses various impurities within the penetration depth of Nb samples, treated by SRF cavity processing techniques like colloidal silica polishing (simulating centrifugal barrel polishing), buffer chemical polishing (BCP), high pressure rinsing (HPR) and degassing under high vacuum (HV) condition at 600{\deg}C for 10hrs. Static, dynamic and slow sputtering modes of Time of flight secondary ion mass spectrometry (TOFSIMS) technique was employed to study the effect of the above treatments on interstitial impurities, hydrocarbons, oxides, acidic residuals, reaction products and metallic contaminations. The study confirms that the impurity distribution in Nb is not only sensitive to the surface treatment, but also to their sequence. Varying the treatment sequence prior to HV degassing treatments affected the final impurity levels in HV degassed bulk Nb samples. BCP treated samples, exhibited minimum hydrocarbon and metallic contamination but, led to extensive contamination of the oxide layer with residuals and reaction products of acids used in BCP solution. HPR treatment, on the other hand was effective in reducing the acidic impurities on the top surface. The study also establishes the application of TOFSIMS technique to analyze and evolve SRF treatments.
Stable Expression of mtlD Gene Imparts Multiple Stress Tolerance in Finger Millet
Ramanna Hema, Ramu S. Vemanna, Shivakumar Sreeramulu, Chandrasekhara P. Reddy, Muthappa Senthil-Kumar, Makarla Udayakumar
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099110
Abstract: Finger millet is susceptible to abiotic stresses, especially drought and salinity stress, in the field during seed germination and early stages of seedling development. Therefore developing stress tolerant finger millet plants combating drought, salinity and associated oxidative stress in these two growth stages is important. Cellular protection through osmotic adjustment and efficient free radical scavenging ability during abiotic stress are important components of stress tolerance mechanisms in plants. Mannitol, an osmolyte, is known to scavenge hydroxyl radicals generated during various abiotic stresses and thereby minimize stress damage in several plant species. In this study transgenic finger millet plants expressing the mannitol biosynthetic pathway gene from bacteria, mannitol-1-phosphate dehydrogenase (mtlD), were developed through Agrobacterium tumefaciens-mediated genetic transformation. mtlD gene integration in the putative transgenic plants was confirmed by Southern blot. Further, performance of transgenic finger millet under drought, salinity and oxidative stress was studied at plant level in T1 generation and in T1 and T2 generation seedlings. Results from these experiments showed that transgenic finger millet had better growth under drought and salinity stress compared to wild-type. At plant level, transgenic plants showed better osmotic adjustment and chlorophyll retention under drought stress compared to the wild-type. However, the overall increase in stress tolerance of transgenics for the three stresses, especially for oxidative stress, was only marginal compared to other mtlD gene expressing plant species reported in the literature. Moreover, the Agrobacterium-mediated genetic transformation protocol developed for finger millet in this study can be used to introduce diverse traits of agronomic importance in finger millet.
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