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A Fully Automated High-Throughput Training System for Rodents
Addressing the neural mechanisms underlying complex learned behaviors requires training animals in well-controlled tasks, an often time-consuming and labor-intensive process that can severely limit the feasibility of such studies. To overcome this constraint, we developed a fully computer-controlled general purpose system for high-throughput training of rodents. By standardizing and automating the implementation of predefined training protocols within the animal’s home-cage our system dramatically reduces the efforts involved in animal training while also removing human errors and biases from the process. We deployed this system to train rats in a variety of sensorimotor tasks, achieving learning rates comparable to existing, but more laborious, methods. By incrementally and systematically increasing the difficulty of the task over weeks of training, rats were able to master motor tasks that, in complexity and structure, resemble ones used in primate studies of motor sequence learning. By enabling fully automated training of rodents in a home-cage setting this low-cost and modular system increases the utility of rodents for studying the neural underpinnings of a variety of complex behaviors
Polarization Sensitive Optical Coherence Tomography for Blood Glucose Monitoring in Human Subjects
A device based on Polarization sensitive optical coherence tomography is
developed to monitor blood glucose levels in human subjects. The device was
initially tested with tissue phantom. The measurements with human subjects for
various glucose concentration levels are found to be linearly dependent on the
degree of circular polarization obtainable from the PS-OCT.Comment: 12 pages, 5 figure
The mcm17 mutation of yeast shows a size-dependent segregational defect of a mini-chromosome
Mini-chromosome-maintenance (mcm) mutants were described earlier as yeast mutants which could not stably maintain mini-chromosomes. Out of these, the ARS-specific class has been more extensively studied and is found to lose chromosomes and mini-chromosomes due to a defect in the initiation of DNA replication at yeast ARSs. In the present study we have identified a number of mcm mutants which show size-dependent loss of mini-chromosomes. When the size of the mini-chromosome was increased, from about 15 kb to about 60 kb, there was a dramatic increase in its mitotic stability in these mutants, but not in the ARS-specific class of mutants. One mutant, mcm17, belonging to the size-dependent class was further characterized. In this mutant, cells carried mini-chromosomes in significantly elevated copy numbers, suggesting a defect in segregation. This defect was largely suppressed in the 60-kb mini-chromosome. A non-centromeric plasmid, the TRP1ARS1 circle, was not affected in its maintenance. This mutant also displayed enhanced chromosome-III loss during mitosis over the wild-type strain, without elevating mitotic recombination. Cloning and sequencing of MCM17 has shown it to be the same as CHL4, a gene required for chromosome stability. This gene is non-essential for growth, as its disruption or deletion from the chromosome did not affect the growth-rate of cells at 23 °C or 37 °C. This work suggests that centromere-directed segregation of a chromosome in yeast is strongly influenced by its length
Non-zero trilinear parameter in the mSUGRA model - dark matter and collider signals at Tevatron and LHC
Phenomenologically viable and interesting regions of parameter space in the
minimal super-gravity (mSUGRA) model with small and small
consistent with the WMAP data on dark matter relic density and the bound on the
mass of the lightest Higgs scalar 114 GeV from LEP2 open up if the
rather adhoc assumption =0, where is the common trilinear soft
breaking parameter, employed in most of the existing analyses is relaxed. Since
this region corresponds to relatively light squarks and gluinos which are
likely to be probed extensively in the very early stages of the LHC
experiments, the consequences of moderate or large negative values of are
examined in detail. We find that in this region several processes including
lightest supersymmetric particle (LSP) pair annihilation, LSP - lighter tau
slepton () coannihilation and LSP - lighter top squark
() coannihilation contribute to the observed dark matter relic
density. %\sout{The possibility that a relic density producing
can be %observed at the current experiments at the Tevatron is wide open.} The
possibility that a that can participate in coannihilation with
the lightest neutralino to satisfy the WMAP bound on relic density and at the
same time be observed at the current experiments at the Tevatron is wide open.
At the LHC a large number of squark - gluino events lead to a very distinctive
semi-inclusive signature +X (anything without a tau lepton)
with a characteristic size much larger than +X or +X
events.Comment: Some minor changes made in the text. To appear in Phys Rev
Gold Market Analyzer using Selection based Algorithm
Gold is the most important and valuable element right from its discovery. It is the most significant element at present and also the most valuable asset to. In the present market scenario the investors use gold as the security for their shares investment. During International trade all the countries use gold as their main mode of transaction. It is seen that all the currencies accepted by the International market are having the gold as the backup for their economy. The prices of gold are rising day by day continuously. As we see in the history of gold market the present prices of gold are much high as compare to the past values and that's why the gold market has attracted the most attention. The paper focus on the continuous changing in the gold rates, investment policies depend on the forecasting of trends in gold which will help the data mining companies to minimize the risk The description of the future situation on the basis of present trends is just not limited to the forecasting the prices. The knowledge discovers by the data mining techniques is gathered from the different gold related websites and also from the jewellers database. It is much more important for the ornaments making companies to know the demand and the requirements for the ornaments during the unstable (uncertain) market conditions. For the classification purpose the maid and sale database was gathered from the nearest jewellery shops of the past 5 years. The prediction is done after complete analysis of the gathered data set. With this the paper concentrate on making the information available about the government and private schemes related to gold market on one place. The paper proposes the system that gives the total access to the registered user and limited access to the unregistered user to get the required information of gold. The latest updates are provided to the registered user by sending mail or text message when the user was offline
Scaling of NonOhmic Conduction in Strongly Correlated Systems
A new scaling formalism is used to analyze nonlinear I-V data in the vicinity
of metal-insulator transitions (MIT) in five manganite systems. An exponent,
called the nonlinearity exponent, and an onset field for nonlinearity, both
characteristic of the system under study, are obtained from the analysis. The
onset field is found to have an anomalously low value corroborating the
theoretically predicted electronically soft phases. The scaling functions above
and below the MIT of a polycrystalline sample are found to be the same but with
different exponents which are attributed to the distribution of the MIT
temperatures. The applicability of the scaling in manganites underlines the
universal response of the disordered systems to electric field
Transport and Magnetic Properties of FexVse2 (x = 0 - 0.33)
We present our results of the effect of Fe intercalation on the structural,
transport and magnetic properties of 1T-VSe2. Intercalation of iron, suppresses
the 110K charge density wave (CDW) transition of the 1T-VSe2. For the higher
concentration of iron, formation of a new kind of first order transition at
160K takes place, which go on stronger for the 33% Fe intercalation.
Thermopower of the FexVSe2 compounds (x = 0 - 0.33), however do not show any
anomaly around the transition. The intercalation of Fe does not trigger any
magnetism in the weak paramagnetic 1T-VSe2, and Fe is the low spin state of
Fe3+.Comment: 7 pages, 8 figures, 2 table
Top squark and neutralino decays in a R-parity violating model constrained by neutrino oscillation data
In a R-parity violating (RPV) model of neutrino mass with three bilinear
couplings and three trilinear couplings , where is
the lepton index, we find six generic scenarios each with a distinctive pattern
of the trilinear couplings consistent with the oscillation data. These patterns
may be reflected in direct RPV decays of the lighter top squark or in the RPV
decays of the lightest superparticle, assumed to be the lightest neutralino.
Typical signal sizes at the Tevatron RUN II and the LHC have been estimated
and the results turn out to be encouraging.Comment: 20 pages, 4 figures, LaTex,typos corrected and reference added for
section 2, a paragraph has been added in the conclusion par
Chaperone-like activity of tubulin. Binding and reactivation of unfolded substrate enzymes
The eukaryotic cytoskeletal protein tubulin is a heterodimer of two subunits, α and β , and is a building block unit of microtubules. In a previous communication we demonstrated that tubulin possesses chaperonelike activities by preventing the stress-induced aggregation of various proteins (Guha, S., Manna, T. K., Das, K. P., and Bhattacharyya, B. (1998) J. Biol. Chem. 273, 30077-30080). As an extension of this observation, we explored whether tubulin, like other known chaperones, also protected biological activity of proteins against thermal stress or increased the yields of active proteins during refolding from a denatured state. We show here that tubulin not only prevents the thermal aggregation of alcohol dehydrogenase and malic dehydrogenase but also protects them from loss of activity. We also show that tubulin prevents the aggregation of substrates during their refolding from a denatured state and forms a stable complex with denatured substrate. The activity of malic dehydrogenase, α -glucosidase, and lactate dehydrogenase during their refolding from urea or guanidium hydrochloride denatured states increased significantly in presence of tubulin compared with that without tubulin. These results suggest that tubulin, in addition to its role in mitosis, cell motility, and other cellular events, might be implicated in protein folding and protection from stress
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