Neutron Acceleration in Uniform Electromagnetic Fields

The question as to whether neutron acceleration can occur in uniform electromagnetic fields is examined. Although such an effect has been predicted using the canonical equations of motion some doubt has been raised recently as to whether it is in principle observable for a spin 1/2 particle. To resolve this issue a gedanken experiment is proposed and analyzed using a wave packet construction for the neutron beam. By allowing arbitrary orientation for the neutron spin as well as for the electric and magnetic fields a non vanishing acceleration of the center of the neutron wave packet is found which confirms the predictions of the canonical formalism.Comment: 11 page

Classical and Quantum Interaction of the Dipole

A unified and fully relativistic treatment of the interaction of the electric and magnetic dipole moments of a particle with the electromagnetic field is given. New forces on the particle due to the combined effect of electric and magnetic dipoles are obtained. Four new experiments are proposed, three of which would observe topological phase shifts.Comment: 10 pages, Latex/Revtex. Some minor errors have been correcte

Gravitational Phase Operator and Cosmic Strings

A quantum equivalence principle is formulated by means of a gravitational phase operator which is an element of the Poincare group. This is applied to the spinning cosmic string which suggests that it may (but not necessarily) contain gravitational torsion. A new exact solution of the Einstein- Cartan-Sciama-Kibble equations for the gravitational field with torsion is obtained everywhere for a cosmic string with uniform energy density, spin density and flux. A novel effect due to the quantized gravitational field of the cosmic string on the wave function of a particle outside the string is used to argue that spacetime points are not meaningful in quantum gravity.Comment: 22 pages, to be published Phys. Rev. D. Some minor changes have been made and a reference has been added to the paper of D.V. Gal'tsov and P.S. Letelier, Phys. Rev. D 47 (1993) 4273, which first contained the metric (2.2) external to the cosmic string. The present paper extends this solution to a regular solution inside the string as wel

Acanthosis nigricans: A flag for insulin resistance

Objectives: Acanthosis nigricans refers to the velvety, black  hyperpigmentation seen in the flexures. It is a cutaneous marker for insulin resistance (IR), some metabolic disorders and rarely malignancy. When secondary to IR, it is asymptomatic, except for the  hyperpigmentation. The neck is the most accessible and easiest to grade. Our aim was to identify the predictive value of the grades of acanthosis nigricans in identifying IR, the predictive value of the textures of acanthosis nigricans in identifying IR, and the diagnostic utility of  acanthosis nigricans grading in comparison to the laboratory tests.Settings and subjects: The institutional ethics committee of Sri  Ramachandra University approved this study. Three hundred, consecutively presenting adults (50 males) with acanthosis nigricans on the neck were enrolled.Design: History, physical parameters and acanthosis nigricans grades, location and textures were noted. An oral glucose tolerance test (OGTT), fasting serum insulin and homeostasis model assessment of IR (HOMA IR) were carried out. The acanthosis nigricans grades were correlated to establish any association. Thirty obese controls without acanthosis nigricans were included.Outcome measures: OGTT, fasting serum insulin and HOMA IR were the outcome measures studied.Results: This cross-sectional study revealed that 94 subjects with acanthosis nigricans (31.34%) had IR. Grades III and IV, and textures II and III, were more predictive of IR. Acanthosis nigricans grading was insignificant in the non-insulin-resistant group. Acne (p-value 0.379), hirsutism (p-value 0.12) and acrochorda (p-value 0.415) were not significantly associated with IR.Conclusion: Severe grades and higher textures of acanthosis nigricans are reliable clinical diagnostic tools for IR. The absence of acanthosis nigricans was not associated with IR. Acanthosis nigricans grading is an inexpensiveand non-invasive way of identifying pre-diabetes

PHYTOCHEMICAL AND PHARMACOLOGICAL EVALUATION OF ACALYPHA COMMUNIS MULL. ARG. FOR THEIR HEPATOPROTECTIVE ACTIVITY

Objective: Acalypha communis is a synonym of Ricinocarpus communis (Müll.Arg.) belonging to the family of Euphorbiaceae. A. communis possess awide variety of activities like antimicrobial. Hence, the present study was intended to evaluate ethanolic leaf extract of A. communis for hepatoprotectiveactivities.Methods: The hepatoprotective activity was studied by paracetamol (2 g/kg) and D-galactosamine (400 mg/kg) induced models. Acute toxicity studyand preliminary phytochemical screening were also studied to evaluate the toxicity.Results: No toxicity profile was observed in rats after oral administration of the ethanolic leaf extract at the dose of 5 g/kg body weight. Thedifferent dose of 200 mg/kg and 400 mg/kg administered with the extract of A. communis. There was significant (p<0.001) reduction in biochemicalparameters with respect to control. Phytochemical screening of the plant extract revealed the presence of tannins, alkaloids, flavonoids and saponins,and terpenoids.Conclusion: It can be concluded that the hepatoprotective activity elucidated by A. communis could be mainly due to the presences of high-value classof compound like the phenolic group as the major content in the plants.Keywords: Acalypha communis, Paracetamol, D-galactosamine, Biochemical parameters and histopathological studies