40 research outputs found
Evidence of Class Transitions in GRS 1915+105 from IXAE Data
GRS 1915+105 shows at least twelve distinct classes of light curves. By
analysing the data obtained from Indian X-ray Astronomy Experiment (IXAE)
instrument aboard IRS-P3 satellite, we show that in at least two days,
transitions between one class to another were observed. In these days the
so-called class went to class and class went to
class. In the frequency-time plane such transitions exhibited change in
quasi-periodic oscillation (QPO) frequency. We could detect that low-frequency
QPOs can occur in anticipation of a class transition several hundred minutes
before the actual transitionComment: 14 pages, 3 figures, Astrophysical Journa
Bioequivalence study of two formulations containing 400 mg dexibuprofen in healthy Indian subjects
Objective: This study presents the results of two-period, two-treatment crossover investigations on 24 healthy Indian male subjects to assess the bioequivalence of two oral formulations containing 400 mg of dexibuprofen (CAS 51146-56-6). An attempt was also made to study the pharmacokinetics of dexibuprofen in the local population of Indian origin.Method: Both of the formulations were administered orally as a single dose separated by a one-week washout period. The concentration of dexibuprofen in plasma was determined by a validated HPLC method with UV detection using carbamazepine as internal standard. The formulations were compared using the parameters area under the plasma concentration-time curve (AUC0-t), area under the plasma concentration-time curve from zero to infinity (AUC0-∞), peak plasma concentration (Cmax), and time to reach peak plasma concentration (tmax).Results: The results of this investigation indicated that there were no statistically significant differences between the logarithmically transformed AUC0-∞ and Cmax values of the two preparations. The 90 % confidence interval for the ratio of the logarithmically transformed AUC0-t, AUC0-∞ and Cmax were within the bioequivalence limit of 0.8-1.25 and the relative bioavailability of the test formulation was 99.04 % of that of reference formulationjok?.Conclusion: Thus, these findings clearly indicate that the two formulations are bioequivalent in terms of rate and extent of drug absorption. Both preparations were well tolerated with no adverse reactions observed throughout the study
Revelations of the E_6/U(1)_N Model: Two-Loop Neutrino Mass and Dark Matter
The E_6/U(1)_N gauge extension of the Supersymmetric Standard Model, first
proposed by Ma, is shown to have exactly the requisite ingredients to realize
the important new idea that dark matter is the origin of neutrino mass. With
the implementation of a discrete Z_2 X Z_2 symmetry, and particle content given
by three {27} representations of E_6, neutrino masses are naturally generated
in two loops, with candidates of dark matter in the loops. All particles of
this model are expected to be at or below the TeV scale, allowing them to be
observable at the LHC.Comment: 10 pages, 3 figure
Electroweak Baryogenesis and Constraints on Left-handed Majorana Neutrino Masses
The lepton number violating interactions generated by the light Majorana
neutrinos can erase the primordial baryon asymmetry of the universe during the
electroweak phase transition. The Majorana masses of the left-handed neutrinos
are constrained to avoid this problem. These constraints do not depend on the
symmetry breaking mechanism.Comment: 10 pages, LATEX file with a postscript file attached at the end with
instructions to prin
Baryon and Lepton Number Assignment in Models
In models there are new particles whose baryon number is not uniquely
assigned. We point out that the baryon and lepton number assignment to these
particles can change the baryogenesis scenario significantly. We consider
left-right symmetric extension of the standard model in which quantum
number is gauged. The identification of with a generator of is
used to define the baryon and lepton numbers for the exotic particles in a way
that the electroweak baryon and lepton number anomaly corresponding to the
group vanishes, {\it i.e.}, there is no non-perturbative baryon or
lepton number violation during the electroweak phase transition. We study some
consequences of the new assignment.Comment: 14 pages, LaTeX file, 1 submitted Figure file(.eps
Models of Neutrino Masses and Baryogenesis
Majorana masses of the neutrino implies lepton number violation and is
intimately related to the lepton asymmetry of the universe, which gets related
to the baryon asymmetry of the universe in the presence of the sphalerons
during the electroweak phase transition. Assuming that the baryon asymmetry of
the universe is generated before the electroweak phase transition, it is
possible to dicriminate different classes of models of neutrino masses. While
see-saw mechanism and the triplet higgs mechanism are preferred, the Zee-type
radiative models and the R-parity breaking models requires additional inputs to
generate baryon asymmetry of the universe during the electroweak phase
transition.Comment: 27 pages including 5 figures; Review article for Pramana: the Indian
Journal of Physic
A novel ensemble learning-based model for network intrusion detection
Abstract The growth of Internet and the services provided by it has been growing exponentially in the past few decades. With such growth, there is also an ever-increasing threat to the security of networks. Several efficient countermeasures have been placed to deal with these threats in the network, such as the intrusion detection system (IDS). This paper proposes an ensemble learning-based method for building an intrusion detection model. The model proposed in this paper has relatively better overall performance than its individual classifiers. This ensemble model is constructed using lightweight machine learning models, i.e., Gaussian naive Bayes, logistic regression and decision tree as the base classifier and stochastic gradient descent as the meta-classifier. The performance of this proposed model and the individual classifiers used to build the ensemble model is trained and evaluated using three datasets, namely, KDD Cup 1999, UNSW-NB15 and CIC-IDS2017. The performance is evaluated for binary class as well as multiclass classifications. The proposed method also incorporates the usage of a feature selection method called Chi-square test to select only the most relevant features. The empirical results definitively prove that using an ensemble classifier can be immensely helpful in the field of intrusion detection system with unbalanced datasets where misclassifications can be costly
From the Editors
As we were completing the final touches on the 8th volume of The Jefferson Medicine Forum, the members of the editing staff could not help but note the vast variety of medicine we are privileged to witness daily. Textbook cases of malaria, herpes zoster ophthalmicus, and Lyme disease mixed among patients with migrating prostatic radiation seeds or reversible encephalophathy due to hypertension are the perfect example of the marvelous diversity of pathology to which we are exposed. Our residents have interests ranging from coronary heart disease to irritable bowel disease and research throughout the spectrum of internal medicine