1,210 research outputs found
Microbial production of polyhydroxy alkanotes (PHA) from Alcaligens spp. and Pseudomonas oleovorans using different carbon sources
Plastics have resistance to biological breakdown that result in its accumulation in the environment. This emphasizes the need to search for biodegradable polymer, which is easily disposable and degradable. Bacteria synthesize and accumulate polyhydroxy alkanote (PHA) as carbon source under limiting conditions of nutrients. The effect of different nutrient conditions on production of PHA by Alcaligens eutrophus, Alcaligens latus and Pseudomonas oleovorans was screened and characterized in this study. The influence of different carbon sources on PHA production showed that, medium with glucose as carbon source produced the maximum PHA content of 4.14 g/l from A. eutrophus. P.oleovorans produced 2.06 g/l from n-octane as carbon source. The functional groups of the extracted PHA granules were identified as C=O group by fourier transform infrared (FTIR) spectroscopy analysis.Biodegrability studies showed that, the PHA produced is degradable by a number of soil microbes making it an ideal environmentally friendly material for regular human use
Universal compression of Gaussian sources with unknown parameters
For a collection of distributions over a countable support set, the worst
case universal compression formulation by Shtarkov attempts to assign a
universal distribution over the support set. The formulation aims to ensure
that the universal distribution does not underestimate the probability of any
element in the support set relative to distributions in the collection. When
the alphabet is uncountable and we have a collection of Lebesgue
continuous measures instead, we ask if there is a corresponding universal
probability density function (pdf) that does not underestimate the value of the
density function at any point in the support relative to pdfs in .
Analogous to the worst case redundancy of a collection of distributions over
a countable alphabet, we define the \textit{attenuation} of a class to be
when the worst case optimal universal pdf at any point in the support is
always at least the value any pdf in the collection assigns to
divided by . We analyze the attenuation of the worst optimal universal pdf
over length- samples generated \textit{i.i.d.} from a Gaussian distribution
whose mean can be anywhere between to and variance
between and . We show that this attenuation is finite,
grows with the number of samples as , and also specify the
attentuation exactly without approximations. When only one parameter is allowed
to vary, we show that the attenuation grows as , again
keeping in line with results from prior literature that fix the order of
magnitude as a factor of per parameter. In addition, we also specify
the attenuation exactly without approximation when only the mean or only the
variance is allowed to vary
Extreme events and event size fluctuations in biased random walks on networks
Random walk on discrete lattice models is important to understand various
types of transport processes. The extreme events, defined as exceedences of the
flux of walkers above a prescribed threshold, have been studied recently in the
context of complex networks. This was motivated by the occurrence of rare
events such as traffic jams, floods, and power black-outs which take place on
networks. In this work, we study extreme events in a generalized random walk
model in which the walk is preferentially biased by the network topology. The
walkers preferentially choose to hop toward the hubs or small degree nodes. In
this setting, we show that extremely large fluctuations in event-sizes are
possible on small degree nodes when the walkers are biased toward the hubs. In
particular, we obtain the distribution of event-sizes on the network. Further,
the probability for the occurrence of extreme events on any node in the network
depends on its 'generalized strength', a measure of the ability of a node to
attract walkers. The 'generalized strength' is a function of the degree of the
node and that of its nearest neighbors. We obtain analytical and simulation
results for the probability of occurrence of extreme events on the nodes of a
network using a generalized random walk model. The result reveals that the
nodes with a larger value of 'generalized strength', on average, display lower
probability for the occurrence of extreme events compared to the nodes with
lower values of 'generalized strength'
Engineering Functional Quantum Algorithms
Suppose that a quantum circuit with K elementary gates is known for a unitary
matrix U, and assume that U^m is a scalar matrix for some positive integer m.
We show that a function of U can be realized on a quantum computer with at most
O(mK+m^2log m) elementary gates. The functions of U are realized by a generic
quantum circuit, which has a particularly simple structure. Among other
results, we obtain efficient circuits for the fractional Fourier transform.Comment: 4 pages, 2 figure
Zero delay synchronization of chaos in coupled map lattices
We show that two coupled map lattices that are mutually coupled to one
another with a delay can display zero delay synchronization if they are driven
by a third coupled map lattice. We analytically estimate the parametric regimes
that lead to synchronization and show that the presence of mutual delays
enhances synchronization to some extent. The zero delay or isochronal
synchronization is reasonably robust against mismatches in the internal
parameters of the coupled map lattices and we analytically estimate the
synchronization error bounds.Comment: 9 pages, 9 figures ; To appear in Phys. Rev.
Antiurolithic Activity of Aqueous Extracts of Leaves Of Capparis Moonii in Ethylene Glycol-Induced Urolithiasis Model Using Rats
This present study evaluated Capparis moonii for urolithiasis and related problems in human. As conventional medicines are typically taken by the oral route, same course of administration was used for assessment of antilithiatic consequence of the extracts of Capparis moonii at a dose of 200mg/kg and Cystone herbal tablet at a dose of 100mg/kg aligned with ethylene glycol induced urolithiasis in rats. In the present study, male rats were selected to persuade urolithiasis because the urinal system of male rats resembles that of humans and also the quantity of stone deposition in female rats was drastically fewer. Substantiation in preceding studies indicated that in response to 14 day period of ethylene glycol (1% v/v) administration, young male albino rats form renal calculi encompassed mainly of calcium oxalate. The biochemical mechanisms for this progression are related to a raised in the urinal concentration of oxalate. Stone development in ethylene glycol fed animals is caused by hyperoxaluria, which causes augmented renal retention and emission of oxalate. In the present study oxalate and calcium excretion progressively augmented in calculi- induced animals, since it is customary that hyperoxaluria, is a far more risk reason in the pathogenesis of renal stones than hypercalciuria, and the changes in urinal oxalate levels are comparatively much more important than those of calcium. Augmented urinal calcium is a feature favouring the nucleation and precipitation of calcium oxalate (or) apatite (calcium phosphate) from urine and consequent crystal growth. Conversely, extracts of Capparis moonii treated animals lowered the levels of oxalate as well as calcium excretion. In the present study, Capparis moonii are having good antioxidant and antiurolithiatic activity, it was proved obviously in this juncture. Meticulous percevings of the patho-physiology of illness and method of action of these herbal medicines have great importance in improvement of effective and safe antiurolithiatic agent. The antioxidant action was calculated as free radical scavenging activity technique, Nitric oxide scavenging, DPPH method, Reducing control determination technique, Hydrogen peroxide method. All the methods depict good response due to thepresence of phenolic compounds and flavonoids in three species. The herbal drugs exert their urolithiatic consequence by varying the ionic content of urine lessening the ca+ and oxalate ion strength or escalating magnesium and citrate excretion and also with diuretic activity. In this respect this information provides a fruitful area for scientific research by willing investigators.An attempt may be made to develop new herbal formulation to treat Kidney stone by Capparis moonii plants. 5this present study we can conclude by using this Capparis moonii, we can go for herbal formulation development to treat Kidney stone
Classical bifurcations and entanglement in smooth Hamiltonian system
We study entanglement in two coupled quartic oscillators. It is shown that
the entanglement, as measured by the von Neumann entropy, increases with the
classical chaos parameter for generic chaotic eigenstates. We consider certain
isolated periodic orbits whose bifurcation sequence affects a class of quantum
eigenstates, called the channel localized states. For these states, the
entanglement is a local minima in the vicinity of a pitchfork bifurcation but
is a local maxima near a anti-pitchfork bifurcation. We place these results in
the context of the close connections that may exist between entanglement
measures and conventional measures of localization that have been much studied
in quantum chaos and elsewhere. We also point to an interesting near-degeneracy
that arises in the spectrum of reduced density matrices of certain states as an
interplay of localization and symmetry.Comment: 7 pages, 6 figure
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