160 research outputs found
Detecting Ontological Conflicts in Protocols between Semantic Web Services
The task of verifying the compatibility between interacting web services has
traditionally been limited to checking the compatibility of the interaction
protocol in terms of message sequences and the type of data being exchanged.
Since web services are developed largely in an uncoordinated way, different
services often use independently developed ontologies for the same domain
instead of adhering to a single ontology as standard. In this work we
investigate the approaches that can be taken by the server to verify the
possibility to reach a state with semantically inconsistent results during the
execution of a protocol with a client, if the client ontology is published.
Often database is used to store the actual data along with the ontologies
instead of storing the actual data as a part of the ontology description. It is
important to observe that at the current state of the database the semantic
conflict state may not be reached even if the verification done by the server
indicates the possibility of reaching a conflict state. A relational algebra
based decision procedure is also developed to incorporate the current state of
the client and the server databases in the overall verification procedure
Three Essays on Robust Estimation of Key Factors Underlying the Changes to the U.S. Income Distribution
This dissertation consists of three chapters and mainly focuses on the robust estimation of different important factors contributing changes to the U.S. income inequality over the last two decades. The primary objective is to precisely estimate different labor market outcomes when the behaviors of the tails of the distribution bear much importance. These studies are very relevant in the current context of the U.S. labor market because over the last three decades the U.S. income distribution have come very skewed and therefore, we are more interested at the behaviors of the the upper and lower-tails of the U.S. income distribution compared to the middle.
The first chapter of the dissertation proposes a semi-parametric procedure to determine the contribution of human capital variables in explaining the changes of U.S. wage distribution function over the period of 1990-2000. The effects of these factors are estimated by using the Chamberlain\u27s two stage Box-Cox quantile regression approach. One of the main contributions of this chapter is that it relaxes the linearity assumption of the conditional quantile function to estimate the counterfactual wage distribution function consistently. This chapter also shows that the proposed method provides better estimates of capturing the effects of human capital variables in the two tails of the U.S. wage distribution while the results of other parts of the distribution are comparable with the estimates of the previous study which used the linear quantile regression approach.
The second chapter proposes a semi-parametric estimation method known as `Box-Cox Unconditional Quantile Regression\u27 to explain the increasing trend of the U.S. wage inequality over the last two decades for men and women separately. Box-Cox Unconditional Quantile Regression is a generalization of the Linear Unconditional Quantile Regression model proposed by Firpo, Fortin and Lemieux (2009). The main contribution of this chapter is to determine the role of unionization in explaining the rising wage gap between the upper and lower tails of the U.S. wage distribution function during the period 1990-2010. I also show that proposed Box-Cox unconditional Quantile Regression model precisely estimates the parameters compared to the Linear Unconditional Quantile Regression model at the two tails of the U.S. wage distribution function while the results of the rest of the part of the distribution are comparable with the estimates of the previous study by Firpo et al. (2009). To summarize, this proposed approach is most applicable in cases where the behavior of the tails of the distribution bears much importance. I find that declining unionization can explain around 20-25 percent of the total fall in the 50/10 percentile wage gap and does not have much impact on the rise in the 90/50 percentile wage gap for men over the period 1990-2010. For women, unionization has very little impact on the rising wage gaps at different parts of the wage distribution over the last two decades.
In the third chapter I propose an extension of Rosen\u27s (1986) theory of equalizing differences model by incorporating the role of different types of cognitive and noncognitive skills in worker\u27s job preference function to explain the U.S. labor market sorting mechanism. I show that ignoring the impact of worker\u27s skills on occupational choice decision leads to bias and inconsistent results because of sample selection specification error. This chapter proposes a solution of the problem by using workers\u27 education level as the proxy of the cognitive skills. This chapter also tests the implication of the proposed labor market sorting model by using the current population survey and Occupational Information Network data sets and finds that a positive and statistically significant relationship exists between noncognitive skills and workers sorting behavior. The empirical results suggest that the relative employment share of women is higher in the occupation in which the people\u27s task is more important because of their job preferences, which depend on the level of different types of noncognitive skills such as interpersonal and social skills. This type of sorting behavior can explain a large portion of the male-female wage gap
Integrability Lost
It is known that classical string dynamics in pure AdS_5\times S^5 is
integrable and plays an important role in solvability. This is a deep and
central issue in holography. Here we investigate similar classical
integrability for a more realistic confining background and provide a negative
answer. The dynamics of a class of simple string configurations in AdS soliton
background can be mapped to the dynamics of a set of non-linearly coupled
oscillators. In a suitable limit of small fluctuations we discuss a
quasi-periodic analytic solution of the system. However numerics indicates
chaotic behavior as the fluctuations are not small. Integrability implies the
existence of a regular foliation of the phase space by invariant manifolds. Our
numerics shows how this nice foliation structure is eventually lost due to
chaotic motion. We also verify a positive Lyapunov index for chaotic orbits.
Our dynamics is roughly similar to other known non-integrable coupled
oscillators systems like Henon-Heiles equations.Comment: Acknowledged grant
A Multi-objective Perspective for Operator Scheduling using Fine-grained DVS Architecture
The stringent power budget of fine grained power managed digital integrated
circuits have driven chip designers to optimize power at the cost of area and
delay, which were the traditional cost criteria for circuit optimization. The
emerging scenario motivates us to revisit the classical operator scheduling
problem under the availability of DVFS enabled functional units that can
trade-off cycles with power. We study the design space defined due to this
trade-off and present a branch-and-bound(B/B) algorithm to explore this state
space and report the pareto-optimal front with respect to area and power. The
scheduling also aims at maximum resource sharing and is able to attain
sufficient area and power gains for complex benchmarks when timing constraints
are relaxed by sufficient amount. Experimental results show that the algorithm
that operates without any user constraint(area/power) is able to solve the
problem for most available benchmarks, and the use of power budget or area
budget constraints leads to significant performance gain.Comment: 18 pages, 6 figures, International journal of VLSI design &
Communication Systems (VLSICS
Confining Backgrounds and Quantum Chaos in Holography
Classical world-sheet string theory has recently been shown to be
nonintegrable and chaotic in various confining string theory backgrounds -- the
AdS soliton background in particular. In this paper we study a minisuperspace
quantization of the theory and look at properties of the spectrum like the
distribution of level spacing, which are indicative of quantum order or chaos.
In the quantum spectrum we find a gradual transition from chaotic (Wigner GOE)
to integrable (Poisson) regime as we look at higher energies. This is expected
since our system is integrable asymptotically, and at higher energies, the
dynamics is entirely dominated by the kinetic terms.Comment: 10 pages, 5 figures; v2: References adde
Dissipative nonlinear dynamics in holography
We look at the response of a nonlinearly coupled scalar field in an
asymptotically AdS black brane geometry and find a behavior very similar to
that of known dissipative nonlinear systems like the chaotic pendulum.
Transition to chaos proceeds through a series of period-doubling bifurcations.
The presence of dissipation, crucial to this behavior, arises naturally in a
black hole background from the ingoing conditions imposed at the horizon.
AdS/CFT translates our solution to a chaotic response of the operator dual to
the scalar field. Our setup can also be used to study quenchlike behavior in
strongly coupled nonlinear systems
A Comparative Study on Physical Variables of Club and Non-Club Cricketers in Kolkata India
The purpose of the study was to compare the physical fitness components among the club and non-club cricketers. 30 (15 club & 15 non-club) cricketers were selected as subjects. The age of the subjects was 17 to 28 years. Age, Height and Weight were taken as personal data. Selected physical fitness components were measured as criterion by standard tests. The subject was taken randomly. Data were collected in the afternoon (3-4:30 p.m.) consecutively four days. Mean, Standard Deviation and independent t-test was used. Significant level was set at 0.05 levels. Club cricketers were significantly better than nonclub cricketers on Agility, Sit-ups & standing broad jump and there were insignificant difference between club and non-club cricketers on selected other physical fitness components
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Linkage of a nitrilase-containing Nit1C gene cluster to cyanide utilization in Pseudomonas fluorescens NCIMB 11764.
Pseudomonas fluorescens NCIMB 11764 (Pf11764) is uniquely able to grow on the poison cyanide as its sole nitrogen source. It does so by converting cyanide oxidatively to carbon dioxide and ammonia, the latter being assimilated into cellular molecules. This requires a complex enzymatic machinery that includes nitrilase and oxygenase enzymes the nature of which are not well understood. In the course of a proteomics analysis aimed at achieving a better understanding of the proteins that may be required for cyanide degradation by Pf11764, an unknown protein of 17.8 kDa was detected in cells exposed to cyanide. Analysis of this protein by ESI-coupled mass spectrometry and bioinformatics searches gave evidence of strong homology with a protein (Hyp1) of unknown function (hypothetical) present in the bacterium Photorhabdus luminescens subsp. laumondii TTO1 (locus plu_1232). A search of available microbial genomes revealed a number of Hyp1 orthologs the genes of which are found in a conserved gene cluster known as Nit1C. Independent studies revealed that in addition to Hyp1, Pf11764 possesses a gene (nit) specifying a nitrilase enzyme whose closest homologue is a nitrilase found in Nit1C gene clusters (77% amino acid identity). DNA sequence analysis has further revealed that indeed, hyp1Pf11764 and nitPf11764 are contained in a cluster that includes also a gene specifying an oxygenase. Given the possible connection of Nit1C-endoded nitrilase and oxygenase enzymes to enzymatic cyanide degradation, there is strong reason for thinking that the genes specifying these enzymes contribute to bacterial growth on cyanide in those bacteria containing the Nit1C cluster. Because the biological function of the Hyp1 protein is currently unknown, it was cloned and the protein expressed in E. coli so that its properties could further be explored. Unfortunately, the expression of the protein in an insoluble form complicated these analyses. However, at least two lines of evidence suggest a possible role as a regulator of gene expression. First, over-expression of the protein was accompanied by the parallel elevation of the putative vector-encoded b-lactamase, implying that Hyp1Pf11764 can affect the expression of other genes. Second, a comparison of the amino acid sequence of select peptide fragments of Hyp1Pf11764, by conducting searches for homology with proteins in the existing nonredundant protein database, consistently revealed motifs in common with those present in bacterial response regulators that are part of two-component signal transduction systems widely distributed in bacteria
PREPARATION AND CHARACTERIZATION OF ANDROGRAPHOLIDE NANOPARTICLES FOR VISCERAL LEISHMANIASIS CHEMOTHERAPY: IN VITRO AND IN VIVO EVALUATIONS
Objective: To overcome low physiological solubility, poor bioavailability, the short plasma half-life of andrographolide (AG), a delivery system based on poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) were developed to increase the efficiency of AG against visceral leishmaniasis (VL). Methods: Andrographolide-PLGA nanoparticles (AGnp) were prepared with Pgp efflux inhibitor vitamin E TPGS (D-α-tocopheryl polyethylene glycol 1000 succinate) by emulsion solvent evaporation method and characterized. Antileishmanial activity was evaluated using in vitro and in vivo VL infection model. Results: The particle size of AGnp was found to be171.4±11.5 nm with an encapsulation efficiency of 81%. The AGnp reduced AG cellular toxicity, retained it's in vitro antileishmanial activity and lead to a reduction (99.9%) of parasite burden in the Leishmania donovani infected spleen and liver. AGnp was more active in infected mice liver at low dose than in spleen. Therapeutic indexes (TI) were 6.9-fold greater in AG and 68-fold in AGnp compared to amphotericin B (AmB) when evaluated in L. donovani infected spleen. Conclusion: Incorporation of AG in PLGA nanoparticles, provided controlled and improved in vivo performance against V
In Silico Molecular Insights on the Structure-Function Aspects of ACC Deaminase of a Non-Pathogenic Klebsiella Pneumoniae
Bacterial 1-aminocyclopropane-1-carboxylic acid deaminase (ACCD) is known to involve in breaking down the 1-aminocyclopropane-1-carboxylic acid (ACC), immediate precursor of ethylene, into a-ketobutyrate and ammonia. This is required when stress (biotic or abiotic) induced ethylene content is accelerated in plant cells resulting in reduction in plant biomass and yield. Klebsiellapneumoniae, although previously considered only as a pathogenic bacteria, there are some strains reported till date to prove it as a plant growth promoting bacteria (PGPB). ACCD activity has reported from the said strain but the present study is emphasized on its molecular proteomic structures and functions studied in silico. The present work revealed that the ACCD of K. pneumoniae is a 36.5 kDatetrameric stable protein found in intracellular condition. The phylogenetic analysis clearly depicts its similarity with several other ACCD reported from different bacterial genera. The structure-function insight would definitely help future researchers in designing wet lab as well as dry lab experiments
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