2,078 research outputs found
Research and development work carried out on edible oysters in Gujarat
Oyster resources survey was conducted by
the transect method from Jakhau in the Gulf of
Kutch to Umargaon in south Gujarat. Crassostrea
gryphoides was dominant followed by Saccostrea
cucullata and C. rividari
A Non - Singular Cosmological Model with Shear and Rotation
We have investigated a non-static and rotating model of the universe with an
imperfect fluid distribution. It is found that the model is free from
singularity and represents an ever expanding universe with shear and rotation
vanishing for large value of time.Comment: 10 pages, late
ESTIMATION OF GUGGULSTERONE-Z IN GOKSHURADI GUGGULU USING REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY
Objective: A study was aimed to estimate guggulsterone-Z (GZ) in Gokshuradi Guggulu (GG).Methods: An analytical method was developed and validated using Waters Alliance high-performance liquid chromatography system (Empower software), equipped with photodiode array detector. Separation was achieved using Phenomenex, C-18 (250 mm×4.6 mm, 5 μ) column. Mobile phase consisted of acetonitrile:water (70:30,v/v). Flow rate was set to 1 ml/min and detection was performed at 251 nm.Results and Discussion: Validation parameters such as linearity, precision, accuracy, limit of detection, limit of quantification, and robustness were performed. Amount of GZ was estimated using linearity equation.Conclusion: GG was found to contain 0.815±0.03 g% w/w GZ. Validated method may be used as one of the parameters to standardize the formulation
Observational study of scalpel versus electrocautery for subcutaneous incision in elective gynaecological surgeries
Background: Considering higher rate of postoperative wound complications in Government set up hospitals, this study was an attempt to compare incision time, incisional blood loss, hospital stay, post-operative pain and postoperative wound complications when subcutaneous tissue is opened with either scalpel or electrocautery in elective gynaecological surgeries after keeping all other clinical and surgical variables same i.e. age, BMI, haemoglobin, incision depth and hospital stay.Methods: This was a prospective observational comparative study conducted in one of the tertiary teaching hospital in Western Maharashtra, India over 12 months. All patients (n=100) were divided into 2 groups. Group A in which skin and subcutaneous tissue was dissected by using scalpel and Group B in which after skin, anterior abdominal wall was opened by using electrocautery. Data analyzed for indication, incisional blood loss, incision time, postoperative pain, wound complications and hospital stay.Results: There were no significant association between preoperative diagnosis and the development of a post-operative wound complications. Mean incision blood loss was found to be significantly higher in group A compared to group B patients. Postoperative pain was significantly higher in group A (P value <0.05). Among wound complications, no statistically significant differences were seen regarding wound complications for the two groups.Conclusions: Electrosurgical dissection for abdominal incision is safe, less time consuming and with less blood loss during subcutaneous incision and produces less postoperative pain. We conclude that the method of subcutaneous tissue incision was unrelated to the development of postoperative abdominal incision problems
Thermal Particle Creation in Cosmological Spacetimes: A Stochastic Approach
The stochastic method based on the influence functional formalism introduced
in an earlier paper to treat particle creation in near-uniformly accelerated
detectors and collapsing masses is applied here to treat thermal and
near-thermal radiance in certain types of cosmological expansions. It is
indicated how the appearance of thermal radiance in different cosmological
spacetimes and in the two apparently distinct classes of black hole and
cosmological spacetimes can be understood under a unifying conceptual and
methodological framework.Comment: 17 pages, revtex (aps, eqsecnum), submitted to PRD, April 199
Radiation from a uniformly accelerating harmonic oscillator
We consider a radiation from a uniformly accelerating harmonic oscillator
whose minimal coupling to the scalar field changes suddenly. The exact time
evolutions of the quantum operators are given in terms of a classical solution
of a forced harmonic oscillator. After the jumping of the coupling constant
there occurs a fast absorption of energy into the oscillator, and then a slow
emission follows. Here the absorbed energy is independent of the acceleration
and proportional to the log of a high momentum cutoff of the field. The emitted
energy depends on the acceleration and also proportional to the log of the
cutoff. Especially, if the coupling is comparable to the natural frequency of
the detector () enormous energies are radiated away
from the oscillator.Comment: 26 pages, 1 eps figure, RevTeX, minor correction in grammar, add a
discussio
Quantum Theory of Non-Relativistic Particles Interacting with Gravity
We investigate the effects of the gravitational field on the quantum dynamics
of non-relativistic particles. We consider N non-relativistic particles,
interacting with the linearized gravitational field. Using the Feynman - Vernon
influence functional technique, we trace out the graviton field, to obtain a
master equation for the system of particles to first order in . The
effective interaction between the particles, as well as the self-interaction is
non-local in time and in general non-markovian. We show that the gravitational
self-interaction cannot be held responsible for decoherence of microscopic
particles due to the fast vanishing of the diffusion function. For macroscopic
particles though, it leads to diagonalization to the energy eigenstate basis, a
desirable feature in gravity induced collapse models. We finally comment on
possible applications.Comment: Latex,14 pages, replaced to correct the titl
Relation Between Einstein And Quantum Field Equations
We show that there exists a choice of scalar field modes, such that the
evolution of the quantum field in the zero-mass and large-mass limits is
consistent with the Einstein equations for the background geometry. This choice
of modes is also consistent with zero production of these particles and thus
corresponds to a preferred vacuum state preserved by the evolution. In the
zero-mass limit, we find that the quantum field equation implies the Einstein
equation for the scale factor of a radiation-dominated universe; in the
large-mass case, it implies the corresponding Einstein equation for a
matter-dominated universe. Conversely, if the classical radiation-dominated or
matter-dominated Einstein equations hold, there is no production of scalar
particles in the zero and large mass limits, respectively. The suppression of
particle production in the large mass limit is over and above the expected
suppression at large mass. Our results hold for a certain class of conformally
ultrastatic background geometries and therefore generalize previous results by
one of us for spatially flat Robertson-Walker background geometries. In these
geometries, we find that the temporal part of the graviton equations reduces to
the temporal equation for a massless minimally coupled scalar field, and
therefore the results for massless particle production hold also for gravitons.
Within the class of modes we study, we also find that the requirement of zero
production of massless scalar particles is not consistent with a non-zero
cosmological constant. Possible implications are discussed.Comment: Latex, 24 pages. Minor changes in text from original versio
Measurement of neutral current e+/-p cross sections at high Bjorken x with the ZEUS detector
The neutral current e+/-p cross section has been measured up to values of
Bjorken x of approximately 1 with the ZEUS detector at HERA using an integrated
luminosity of 187 inv. pb of e-p and 142 inv. pb of e+p collisions at sqrt(s) =
318GeV. Differential cross sections in x and Q2, the exchanged boson
virtuality, are presented for Q2 geq 725GeV2. An improved reconstruction method
and greatly increased amount of data allows a finer binning in the high-x
region of the neutral current cross section and leads to a measurement with
much improved precision compared to a similar earlier analysis. The
measurements are compared to Standard Model expectations based on a variety of
recent parton distribution functions.Comment: 39 pages, 9 figure
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