bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of new pyrrole and pyrrolo[2,3-d]pyrimidine derivatives of potential antioxidant activity
Authors: El-Bayouki Khairy Abdelhameed Mohsen , Basyouni Wahid Mohmoud , Mostafa Eslam Attya
Published: August 2010

New 2-amino-3-cyanopyrrole derivatives were prepared and converted to 7-deazapurines. 7-Deazaadenine6was synthesized by different methods and alkylated with alkyl iodides to afford the quaternized 3-alkylpyrrolopyrimidinium iodide salts8. The latter salts were dequaternized toN-alkylpyrrolo[2,3-d]pyrimidin-4-amines12. Compounds12were identical to the products obtained from reactions of 4-chloro-7-(4-fluorophenyl)-5-p-tolyl-7H-pyrrolo[2,3-d]pyrimidine11with methyl- or ethylamine in the presence of a catalyst. The thione13and its related 4-methylthio- and 4-ylcarbonothioate derivatives14a,14bwere obtained. The triazolo-17a–17e, benzenesulfonamido-19, and tetrazolopyrrolopyrimidine21derivatives were synthesized. Several examples of the synthesized pyrrole- and pyrrolo[2,3-d]pyrimidine derivatives showed high to remarkable antioxidant scavenging activity as measured by their ability to scavenge the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical
The optimization of the electrochemical preparation of Pedot-Prussian blue hybrid electrode material and application in electrochemical sensors
Authors: Lupu Stelian , Totir Nicolae
Published: August 2010

The electrochemical preparation, characterization and analytical applications of a hybrid material consisting of poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer and Prussian Blue (PB; iron(III) hexacyanoferrate(II)) are presented. The hybrid material was prepared by a two-steps method. In a first step, the organic conducting polymer coating was deposited onto platinum electrode surface from an aqueous solution containing the monomer and ferricyanide ions. In the second step, the resulted modified electrode Pt|PEDOT- FeCN was immersed in an aqueous solution containing Fe3+ ions and the electrode potential was cycled between 0.6 and –0.4 V. The in situ formation of PB inside the PEDOT matrix has been demonstrated using cyclic voltammetry and electrochemical quartz crystal microbalance. The hybrid material maintains the electrochemical features of each component, i.e. organic and inorganic components. The inorganic component showed electrochemical activity only for the Prussian blue/Everitt’s salt redox system. The hybrid material displayed electrocatalytic activity towards dopamine oxidation in the presence of a large excess of ascorbic acid.
The right to treatment for self-inflicted conditions
Authors: Golan Ofra
Published: August 2010

The increasing awareness of personal health responsibility had led to the claim that patients with ‘self-inflicted’ conditions have less of a right to treatment at the public's expense than patients whose conditions arose from ‘uncontrollable’ causes. This paper suggests that regardless of any social decision as to the limits and scope of individual responsibility for health, the moral framework for discussing this issue is equality. In order to reach a consensus, discourse should be according to the common basis of all theories of justice, Aristotle's formal principle of justice: ‘equals must be treated equally and unequals must be treated unequally, in proportion to the relevant inequality’. This paper deals with the question of whether and under what circumstances risk-taking behaviour could be regarded as a ‘relevant inequality’ with respect to the right to health care. Following a discussion of the relevant inequalities in health care, the conclusion is reached that the fact that the condition was avoidably caused by the patient and is therefore his or her fault can not be regarded necessarily as a relevant inequality. Therefore, the issue is one of societal support for health care; after defining relevant inequalities in this respect, the paper attempts to apply them to self-inflicted conditions. This analysis reveals that, in theory, it may be just to restrict societal support in such cases. However, the application of this conclusion requires proof of many factual claims—for which there is often very limited evidence.
Impacts of salinity and simulated herbivory on survival and reproduction of the threatened Gulf of St. Lawrence Aster,Symphyotrichum laurentianum
Authors: Ancheta Justin , Heard Stephen B. , Lyons Jeremy W.
Published: August 2010

Halophytic plants may experience joint, and potentially interacting, effects of salinity and herbivory on their survival and reproduction. We investigated the impacts of salinity and (simulated) herbivory on fitness in the Gulf of St. Lawrence Aster ( Symphyotrichum laurentianum (Fernald) Nesom; Asteraceae). In natural populations, this species experiences varying soil salinity and spill-over herbivory from insects associated with neighbouring seaside goldenrod ( Solidago sempervirens  L.). We subjected S. laurentianum individuals to three levels of simulated herbivory (0%, 20%, and 40% leaf-area removal) and three levels of salinity (0, 10, and 20 g·L–1) in three runs of a growth-chamber experiment. The effects of salinity and herbivory were always additive. Salinity consistently and strongly reduced survivorship, by as much as 80% at 20 g·L–1salt, but significantly affected the seed set of survivors in only one run. Herbivory reduced survival significantly in one run (by 42% at 40% leaf-area removal) and reduced seed set of survivors (by 36% at 40% leaf-area removal) in another. While both stresses can have important effects on S. laurentianum fitness, the effects of salinity were more consistently strong than were the effects of herbivory, for both survival and seed set.
Mapping genetic variation and seed zones forBromus carinatusin the Blue Mountains of eastern Oregon, USAIn this article, mention of companies or trade names does not constitute an endorsement of any product or procedure.
Authors: Johnson R. C. , Erickson Vicky J. , Mandel Nancy L. , St Clair J. Bradley , Vance-Borland Kenneth W.
Published: August 2010

Seed transfer zones ensure that germplasm selected for restoration is suitable and sustainable in diverse environments. In this study, seed zones were developed for mountain brome ( Bromus carinatus Hook. & Arn.) in the Blue Mountains of northeastern Oregon and adjoining Washington. Plants from 148 Blue Mountain seed source locations were evaluated in common-garden studies at two contrasting test sites. Data on phenology, morphology, and production were collected over two growing seasons. Plant traits varied significantly and were frequently correlated with annual precipitation and annual maximum temperature at seed source locations (P < 0.05). Plants from warmer locations generally had higher dry matter production, longer leaves, wider crowns, denser foliage, and greater plant height than those from cooler locations. Regression models of environmental variables with the first two principal components (PC 1 and PC 2) explained 46% and 40% of the total variation, respectively. Maps of PC 1 and PC 2 generally corresponded to elevation, temperature, and precipitation gradients. The regression models developed from PC 1 and PC 2 and environmental variables were used to map seed transfer zones. These maps will be useful in selecting mountain brome seed sources for habitat restoration in the Blue Mountains.
Phosphorus and land-use changes are significant drivers of cladoceran community composition and diversity: an analysis over spatial and temporal scales
Authors: Richard Albert Marc , Chen Guangjie , MacDonald Graham K. , Vermaire Jesse C. , Bennett Elena M. , Gregory-Eaves Irene
Published: August 2010

We conducted paleolimnological studies over spatial and temporal gradients to define the responses of subfossil cladoceran community composition and diversity to changes in land use and phosphorus concentrations in shallow lakes. We predicted that watershed disturbance by humans, through its impact on water quality, would explain significant variation in cladoceran diversity and composition. Across lakes, water-column total phosphorus concentration was a significant (p < 0.05) predictor of the subfossil cladoceran community composition. Chydorid diversity was also found to be related significantly to phosphorus concentration (r = –0.55, p < 0.05) and the proportion of disturbed land in the watershed (r = –0.47, p < 0.05). However, net load of phosphorus to the watershed rather than proportion of watershed disturbance was a significant predictor of chydorid diversity (r = –0.86, p < 0.001) in our temporal analysis of an eutrophying lake. Given that phosphorus loading to surface waters is often related to phosphorus concentrations in soils, we suggest that the net phosphorus load to the watershed is a more sensitive metric of land-use change and necessary for detecting ecological responses in time series data.
A comparison of stock and individual identification for sockeye salmon (Oncorhynchus nerka) in British Columbia provided by microsatellites and single nucleotide polymorphisms
Authors: Beacham Terry D. , McIntosh B. , Wallace C.
Published: August 2010

Variation at 14 microsatellite loci, one major histocompatibility complex (MHC) locus, and 49 single nucleotide polymorphism (SNPs) loci was surveyed in 44 populations of sockeye salmon ( Oncorhynchus nerka ) over 16 regions from southern and central British Columbia, Canada. Sequential addition of the five highest rated SNPs to the suite of 14 microsatellites provided the equivalent average accuracy when compared with the current suite of microsatellites and MHC. Six microsatellites provided the equivalent average stock identification resolution and individual assignment accuracy compared with 46 SNPs. For regional stock compositions, 53–104 SNPs were projected to be required to provide accuracy and precision equivalent to the microsatellites. For population-specific stock compositions, 75–79 SNPs were projected to be required to provide accuracy and precision equivalent to the microsatellites. Equivalency in individual assignment accuracy to region was estimated to require 100 SNPs of the quality evaluated in the study, whereas equivalent accuracy in assignment to specific populations was estimated to require 124 SNPs. Applications that incorporate the existing power of a combined microsatellite–SNP approach are the best current technique available for sockeye salmon stock identification applications in southern British Columbia.
Are seasonal lakes as productive as permanent lakes? A case study from Ireland
Authors: Cunha Pereira Helder , Allott Norman , Coxon Catherine
Published: August 2010

This paper compares, for the first time, nutrient levels and chlorophyll a measured in a set of seasonal lakes with those reported for permanent lakes in the literature. Twenty-two turloughs (karstic seasonal lakes) in western Ireland were sampled monthly from the onset of flooding (October) until they dried out (6 to 9 months). The turloughs showed similar levels of nutrients and chlorophyll a to those reported for Irish and international lakes. Chlorophyll a peaked between November and February in the majority of turloughs, sometimes with values higher than those measured in mesotrophic lakes in summer. A significant log-linear regression was found between total phosphorus and chlorophyll a, which suggests P limitation of algal biomass in the majority of the turloughs. The regression characteristics were not significantly different than those described in similar studies of permanent lakes. Patterns in seasonal variation of nutrients are also presented, their underlying causes being discussed in relation to their transport within catchments. Our results show that despite being predominantly winter phenomena, turloughs can be as productive as permanent lakes.
Testing early life connectivity using otolith chemistry and particle-tracking simulations
Authors: Ashford Julian , La Mesa Mario , Fach Bettina A. , Jones Christopher , Everson Inigo
Published: August 2010

We measured the otolith chemistry of adult Scotia Sea icefish ( Chaenocephalus aceratus ), a species with a long pelagic larval phase, along the Antarctic Circumpolar Current (ACC) and compared the chemistry with simulated particle transport using a circulation model. Material laid down in otolith nuclei during early life showed (i) strong heterogeneity between the Antarctic Peninsula and South Georgia consistent with a population boundary, (ii) evidence of finer-scale heterogeneity between sampling areas on the Antarctic Peninsula, and (iii) similarity between the eastern and northern shelves of South Georgia, indicating a single, self-recruiting population there. Consistent with the otolith chemistry, simulations of the large-scale circulation predicted that particles released at depths of 100–300 m on the Antarctic Peninsula shelf during spring, corresponding to hatching of icefish larvae from benthic nests, are transported in the southern ACC, missing South Georgia but following trajectories along the southern Scotia Ridge instead. These results suggest that the timing of release and position of early life stages in the water column substantially influence the direction and extent of connectivity. Used in complement, the two techniques promise an innovative approach for generating and testing predictions to resolve early dispersal and connectivity of populations related to the physical circulation of oceanic systems.
Towards relativistic atomic physics. Part 1. The rest-frame instant form of dynamics and a canonical transformation for a system of charged particles plus the electro-magnetic field
Authors: Alba David , Crater Horace W. , Lusanna Luca
Published: August 2010

A complete exposition of the rest-frame instant form of dynamics for arbitrary isolated systems (particles, fields, strings, fluids) admitting a Lagrangian description is given. The starting point is the parametrized Minkowski theory describing the system in arbitrary admissible noninertial frames in Minkowski space-time, which allows one to define the energy-momentum tensor of the system and to show the independence of the description from the clock synchronization convention and from the choice of the 3-coordinates. The restriction to the inertial rest frame, centered on the inertial observer having the Fokker–Pryce center-of-inertia world line, and the study of relativistic collective variables replacing the nonrelativistic center of mass lead to the description of the isolated system as a decoupled globally defined noncovariant canonical external center of mass carrying a pole–dipole structure (the invariant mass M and the rest spin [Formula: see text] of the system) and an external realization of the Poincaré group. Mc and [Formula: see text] are the energy and angular momentum of a unfaithful internal realization of the Poincaré group built with the energy-momentum tensor of the system and acting inside the instantaneous Wigner 3-spaces where all the 3-vectors are Wigner covariant. The vanishing of the internal 3-momentum and of the internal Lorentz boosts eliminate the internal 3-center of mass inside the Wigner 3-spaces, so that at the end the isolated system is described only by Wigner-covariant canonical internal relative variables. Then an isolated system of positive-energy-charged scalar articles with mutual Coulomb interaction plus a transverse electromagnetic field in the radiation gauge is investigated as a classical background for defining relativistic atomic physics. The electric charges of the particles are Grassmann-valued to regularize the self-energies. The external and internal realizations of the Poincaré algebra in the rest-frame instant form of dynamics are found. This allows one to define explicitly the rest-frame conditions and their gauge-fixings (needed for the elimination of the internal 3-center of mass) for this isolated system. It is shown that there is a canonical transformation that allows one to describe the isolated system as a set of Coulomb-dressed charged particles interacting through a Coulomb plus Darwin potential plus a free transverse radiation field: these two subsystems are not mutually interacting (the internal Poincaré generators are a direct sum of the two components) and are interconnected only by the rest-frame conditions and the elimination of the internal 3-center of mass. Therefore in this framework with a fixed number of particles there is a way out from the Haag theorem, at least at the classical level.
Towards relativistic atomic physics. Part II. Collective and relative relativistic variables for a system of charged articles plus the electromagnetic field
Authors: Alba David , Crater Horace W. , Lusanna Luca
Published: August 2010

In this second paper, we complete the classical description of an isolated system of “charged positive-energy particles, with Grassmann-valued electric charges and mutual Coulomb interaction, plus a transverse electromagnetic field” in the rest-frame instant form of dynamics. In particular, we show how to determine a collective variable associated with the internal 3-center of mass on the instantaneous 3-spaces, to be eliminated with the constraints [Formula: see text]. Here, [Formula: see text] is the Lorentz boost generator in the unfaithful internal realization of the Poincaré group and its vanishing is the gauge-fixing to the rest-frame conditions [Formula: see text]. We show how to find this collective variable for the following isolated systems: (a) charged particles with a Coulomb plus Darwin mutual interaction; (b) transverse radiation field; (c) charged particles with a mutual Coulomb interaction plus a transverse electro-magnetic field. Then we define the Dixon multipolar expansion for the open particle subsystem. We also define the relativistic electric dipole approximation of atomic physics in the rest-frame instant form and we find a possible relativistic generalization of the electric dipole representation.
Elastic properties of zinc-phosphate glasses doped with erbium trioxide
Authors: Eraiah B. , Ramakrishnaiah  , Anavekar R. V.
Published: August 2010

New glasses of the system xEr2O3-(60-x)ZnO-40P2O5 (where x = 0.1 to 0.5 mol%) have been prepared by using a conventional meltquenching method. We have measured the densities of these glasses by using a displacement method, and corresponding molar volumes have also been calculated. We have measured both longitudinal and transverse ultrasonic sound velocities of these glasses using a pulse-echo superposition method. These ultrasonic velocities have been used to calculate the elastic moduli, Poisson ratio, and Debye temperatures. The variations of density, molar volume, ultrasonic sound velocities, elastic moduli, Poisson ratio, and Debye temperature have been discussed with respect to Er2O3 concentration.
The unsteady Boltzmann kinetic equation and non-equilibrium thermodynamics of an electron gas for the Rayleigh flow problem
Authors: Abourabia A. M. , Abdel Wahid T. Z.
Published: August 2010

In the framework of irreversible thermodynamics, the characteristics of the Rayleigh flow problem of a rarified electron gas extracted from neutral atoms is examined and proved to obey the entropic behavior for gas systems. A model kinetic equation of the BGK (Bhatnager–Gross–Krook) type is solved, using the method of moments with a two-sided distribution function. Various macroscopic properties of the electron gas, such as the mean velocity, the shear stress, and the viscosity coefficient, together with the induced electric and magnetic fields, are investigated with respect to both distance and time. The distinction between the perturbed velocity distribution functions and the equilibrium velocity distribution function at different time values is illustrated. We restrict our study to the domain of irreversible thermodynamics processes with small deviation from the equilibrium state to estimate the entropy, entropy production, entropy flux, thermodynamic force, and kinetic coefficient and verify the celebrated Boltzmann H-theorem for non-equilibrium thermodynamic properties of the system. The ratios between the different contributions of the internal energy changes, based upon the total derivatives of the extensive parameters, are predicted via Gibbs’ equation for both diamagnetic and paramagnetic plasmas. The results are applied to a typical model of laboratory argon plasma.
Longitudinal coupling impedance for particle beams with Gaussian charge distributions in the longitudinal and transverse directions
Authors: Okoor Sondos , Al-Khateeb A. M. , Odeh I. M.
Published: August 2010

The longitudinal coupling impedance is obtained analytically for a smooth and resistive cylindrical pipe of finite wall thickness. We assumed a particle beam with Gaussian charge distribution in the longitudinal and transverse directions. For wall thicknesses d less than the skin depth, the impedance increases because of coupling with the vacuum outside the pipe, while for thicknesses d nearly of the order of the skin depth, the impedance becomes independent of the wall thickness. The resistive wall impedance decreases with increasing wall conductivity and it has its maximum values at low frequencies. By increasing beam energies, the space charge impedance decreases while the resistive wall contribution increases. Gaussian and uniform beams have nearly the same impedance at low energy, independent of the wall thickness, while at higher energies obvious differences are observed at wall thicknesses below the skin penetration depth.
Quantitative spectroscopy of the aurora. VI. The auroral spectrum from 275 to 815 nm observed by the OSIRIS spectrograph on board the Odin spacecraft
Authors: Gattinger R. L. , Vallance Jones A. , Degenstein D. A. , Llewellyn E. J.
Published: August 2010

Terrestrial auroral spectra over the 275 to 815 nm wavelength range have been recorded by the OSIRIS imaging spectrograph on board the Odin spacecraft. The spectra are from the dark polar region and are averaged over limb tangent altitudes from 100 to 105 km. All wavelengths are exposed simultaneously, thus avoiding the effect of temporal intensity variations inherently present in spectrally scanning systems. Particular care has been taken to quantify the relative spectral sensitivity over the entire wavelength range, and there is an estimated 5% precision in the measurements. To maintain accurate on-orbit spectral calibrations, an atmospheric radiation model with multiple Rayleigh scatter is employed to regularly update the OSIRIS spectral response throughout the mission. A calibrated auroral spectrum is presented, together with matching synthetic spectra for many of the observed features, for potential use as a reference spectrum in general atmospheric research. The relative intensities of the brighter auroral band systems and atomic lines are reviewed. Finally, the observed spectrum is made freely available in digital format in long term archives.
Intermittency and related issues in 16O-Ag/Br collision at 200A GeV/c
Authors: Ghosh M. K. , Haldar P. K. , Manna S. K. , Mukhopadhyay A. , Singh G.
Published: August 2010

In this paper we present some results on the nonstatistical fluctuation in the 1-dimensional (1-d) density distribution of singly charged produced particles in the framework of the intermittency phenomenon. A set of nuclear emulsion data on 16O-Ag/Br interactions at an incident momentum of 200A GeV/c, was analyzed in terms of different statistical methods that are related to the self-similar fractal properties of the particle density function. A comparison of the present experiment with a similar experiment induced by the 32S nuclei and also with a set of results simulated by the Lund Monte Carlo code FRITIOF is presented. A similar comparison between this experiment and a pseudo-random number generated simulated data set is also made. The analysis reveals the presence of a weak intermittency in the 1-d phase space distribution of the produced particles. The results also indicate the occurrence of a nonthermal phase transition during emission of final-state hadrons. Our results on factorial correlators suggests that short-range correlations are present in the angular distribution of charged hadrons, whereas those on oscillatory moments show that such correlations are not restricted only to a few particles. In almost all cases, the simulated results fail to replicate their experimental counterparts.
Multifractal detrended fluctuation analysis of SENSEX fluctuation in the Indian stock market
Authors: Dutta Srimonti
Published: August 2010

The fluctuation of SENSEX in the Indian stock market for the period Jan 2003–Dec 2009 is studied using the multifractal detrended fluctuation analysis (MFDFA) approach. The effect of the fall in the stock market in 2008 is also investigated. The data exhibits that the nonstationary time series of SENSEX fluctuations are multifractal in nature. An increase in the degree of multifractality prior to the anomalous behaviour in the SENSEX values is also observed. The increase in the degree of correlation for the period 2007–2009 is also responsible for the meteoric rise and the catastrophic fall in the values of SENSEX.
Electric field emission of electrons from negatively charged spherical particles in a dusty plasma in the regime of nonlinear screening
Authors: Prakash Gyan
Published: August 2010

This note presents a discussion of the electric field emission from negatively charged spherical particles in a dusty plasma in the regime of nonlinear screening. Using the appropriate representation of the nonlinear screening by Gurevich and the matrix method, the tunneling probability of an electron through the potential energy barrier around the particle has been evaluated as a function of its radial energy; corresponding values of the current density have also been obtained. A discussion of numerical results, thus obtained concludes the presentation.
The effects of variable fluid properties and viscous dissipation on forced convection of viscoelastic liquids in a thin film over an unsteady stretching sheet
Authors: Abd El-Aziz Mohamed
Published: August 2010

An analysis is performed to study the effect of variable viscosity and variable thermal conductivity on the flow and heat transfer of a thin viscoelastic liquid (obeying Walters' liquid B model) film on a horizontal unsteady stretching sheet taking into account the effect of viscous dissipation. The fluid viscosity is assumed to decrease exponentially with temperature but the thermal conductivity is assumed to vary as a linear function of temperature. Numerical solutions are obtained for some representative values of the viscosity and thermal conductivity variation parameters, unsteadiness parameter, and Eckert number. Typical temperature and velocity profiles, dimensionless film thickness, free-surface velocity and temperature, local skin-friction coefficient, and the local surface heat flux are obtained for a wide range of governing parameters. In general, it is found that a viscoelastic fluid is more sensitive to the variable fluid properties effect than a Newtonian fluid. Also, for constant and (or) variable fluid properties, the film thickness and the local surface heat flux of a viscoelastic fluid is small compared to that of a Newtonian fluid. For all values of the variable viscosity parameter and for both viscoelastic and Newtonian fluid films, the viscous dissipation effect increases the free-surface temperature significantly whereas it reduces the heat transfer rate markedly. However, viscous dissipation does not influence the velocity profiles of both Newtonian and viscoelastic liquid films impressively although the film thickness changes noticeably.
The first-order structural phase transition of YSb
Authors: Fu Hongzhi , Liu WenFang , Gao Tao
Published: August 2010

The high-pressure induced phase transition of YSb has been studied using the density functional theory method within the generalized gradient approximation. It was found that the first-order structural phase transition began to occur at 30.8 GPa, agreeing well with available experiments and theoretical calculations. In this phase transition, we do not find changes in the heat capacity and thermal expansion coefficients at lower and higher temperature, but the transition pressures decrease with temperature. The bulk modulus and Debye temperature decrease with increasing temperature, while they increase with increasing pressure. Also, the density of states and band structure of these two compounds with B1 and B2 structures have been presented and analyzed.
THERMODYNAMIC STABILITY OF A FLUID WITH VARIABLE EQUATION OF STATE
Authors: MAZUMDER NAIRWITA , BISWAS RITABRATA , CHAKRABORTY SUBENOY
Published: August 2010

This paper deals with general thermodynamics for the universe filled with a perfect fluid, obeying an equation of state p = ω(z)ρ where the varying equation of the state parameter is chosen as two-index parametrization models namely: (a) linear redshift parametrization: ω(z) = ω0 + ω1z or (b) Jassal–Bagla–Padmanabhan (JBP) parametrization: [Formula: see text] where ω0, ω1 are constants. The behavior of temperature and the thermodynamic stability have been discussed. The thermal equation of state depends on both temperature and volume. As the universe evolves the fluid cools down obeying third law of thermodynamics and there will be thermodynamic stability during the expansion process without any phase transition or passing through any critical point.
SOME COSMOLOGICAL MODELS IN SCALAR–TENSOR THEORIES
Authors: SINGH J. K.
Published: August 2010

A class of non-static solutions to the Einstein field equations has been investigated in the context of Bianchi type-V spacetime in a family of scalar–tensor theories in the presence as well as absence of the magnetic field. The physical and kinematical behaviors of the models have been discussed. The energy conditions of the models have also been verified.
DILUTION OF ZERO-POINT ENERGIES IN THE COSMOLOGICAL EXPANSION
Authors: BRANCHINA VINCENZO , ZAPPALÀ DARIO
Published: August 2010

The vacuum fluctuations of all quantum fields filling the universe are supposed to leave enormous energy and pressure contributions which are incompatible with observations. It has been recently suggested that, when the effective nature of quantum field theories is properly taken into account, vacuum fluctuations behave as a relativistic gas rather than as a cosmological constant. Accordingly, zero-point energies are tremendously diluted by the universe expansion but provide an extra contribution to radiation energy. Ongoing and future cosmological observations could offer the opportunity to scrutinize this scenario. The presence of such additional contribution to radiation energy can be tested by using primordial nucleosynthesis bounds or measured on Cosmic Background Radiation anisotropy.
Resilient localization for sensor networks in outdoor environments
Authors: Kwon Youngmin , Mechitov Kirill , Sundresh Sameer , Kim Wooyoung , Agha Gul
Published: August 2010

The process of determining the physical locations of nodes in a wireless sensor network is known as
localization
. Self-localization is critical for large-scale sensor networks, because manual or assisted localization is often impractical due to time requirements, economic constraints, or inherent limitations of the deployment scenarios. We propose scalable solutions for reliably localizing wireless sensor networks in environments conducive to several types of ranging errors. We follow a hybrid hardware-software approach for acoustic ranging or radio interferometry to acquire internode distance measurements, and a resilient self-localization algorithm to compute the node location estimates. The acoustic ranging method improves on previous work, extending the practical measurement range up to 35 m in grassy outdoor environments, achieving a distance-invariant median measurement error of about 1% (33 cm). The localization algorithm is based on
least-squares scaling
with soft constraints. Empirical evaluation using ranging results obtained from sensor network field experiments and simulations confirms that our approach is more resilient than multidimensional scaling (MDS) algorithms against large-magnitude ranging errors and sparse range measurements: conditions that are common in large-scale outdoor sensor network deployments.
Modeling latency—lifetime trade-off for target detection in mobile sensor networks
Authors: Wang Chao , Ramanathan Parameswaran , Saluja Kewal K.
Published: August 2010

Two important measures of performance for the surveillance applications of the mobile sensor networks are detection latency and system lifetime. Previous work on modeling detection delay has assumed that sensor measurements are delivered to the fusion center with zero delay. Such approaches can require excessive energy, resulting into reduced lifetime. This article argues that a trade-off between detection latency and system lifetime can be made by employing an energy aware transmission scheme. The article formulates the trade-off as an optimization problem, and presents an analytic method to model both detection latency and system lifetime. The model is substantiated by using simulation.
Everywhere sparse approximately optimal minimum energy data gathering and aggregation in sensor networks
Authors: Kalpakis Konstantinos
Published: August 2010

We consider two related data gathering problems for wireless sensor networks (WSNs). The MLDA problem is concerned with maximizing the system lifetime
T
so that we can perform
T
rounds of data gathering with in-network aggregation, given the initial available energy of the sensors. The M
2
EDA problem is concerned with minimizing the maximum energy consumed by any one sensor when performing
T
rounds of data gathering with in-network aggregation, for a given
T
.

We provide an effective algorithm for finding an everywhere sparse integral solution to the M
2
EDA problem which is within a factor of α = 1+ 4
n
/
T
of the optimum, where
n
is the number of nodes. A solution is everywhere sparse if the number of communication links for any subset
X
of nodes is
O
(
X
), in our case at most 4|
X
|. Since often
T
= ω(
n
), we obtain the first everywhere sparse, asymptotically optimal integral solutions to the M
2
EDA problem. Everywhere sparse solutions are desirable since then almost all sensors have small number of incident communication links and small overhead for maintaining state.

We also show that the MLDA and M
2
EDA problems are essentially equivalent, in the sense that we can obtain an optimal fractional solution to an instance of the MLDA problem by scaling an optimal fractional solution to a suitable instance of the M
2
EDA problem. As a result, our algorithm is effective at finding everywhere sparse, asymptotically optimal, integral solutions to the MLDA problem, when the initial available energy of the sensors is sufficient for supporting optimal system lifetime which is ω(
n
).
Identification of Cognitive Processes of Effective and Ineffective Students During Computer Programming
Authors: Renumol V.G. , Janakiram Dharanipragada , Jayaprakash S.
Published: August 2010

Identifying the set of cognitive processes (CPs) a student can go through during computer programming is an interesting research problem. It can provide a better understanding of the human aspects in computer programming process and can also contribute to the computer programming education in general. The study identified the presence of a set of 42 CPs in computer programming (C language). The study used Verbal Protocol Analysis (VPA) in identifying these CPs. It is a qualitative study on the Verbal Protocols (VPs) of 19 students. Some of the CPs have been inferred by referring to the literature and some have been additionally identified by this study. The additional CPs found are confusion, hypothesis, interrogation, iteration, monitoring, recollection, recurrence, and translation. It is observed that programming involves the interplay of lower and higher CPs and needs various cognitive skills, which increase the processing load on the brain and make the programming process difficult and complex to learn and practice. The same set of CPs was found in both the effective and ineffective subjects. The research results can provide deeper knowledge to teachers on cognitive aspects of programming and the cognitive behavior of students during the programming process.
MLeXAI
Authors: Russell Ingrid , Markov Zdravko , Neller Todd , Coleman Susan
Published: August 2010

Our approach to teaching introductory artificial intelligence (AI) unifies its diverse core topics through a theme of machine learning, and emphasizes how AI relates more broadly with computer science. Our work, funded by a grant from the National Science Foundation, involves the development, implementation, and testing of a suite of projects that can be closely integrated into a one-term AI course. Each project involves the development of a machine learning system in a specific application. These projects have been used in six different offerings over a three-year period at three different types of institutions. While we have presented a sample of the projects as well as limited preliminary experiences in other venues, this article presents the first assessment of our work over an extended period of three years. Results of assessment show that the projects were well received by the students. By using projects involving real-world applications we provided additional motivation for students. While illustrating core concepts, the projects introduced students to an important area in computer science, machine learning, thus motivating further study.
Risk forecast using hidden Markov models
Authors: Pak Charles , Cannady James
Published: August 2010

Today's fast moving technologies create innovative ideas, products, and services, but they also bring with them new security risks. The gap between new technologies and the security needed to keep them from opening up new risks in information systems (ISs) can be difficult to close completely. Changes in ISs are inevitable because computing environments, intentionally or unintentionally, are always changing. These changes bring with them vulnerabilities on new or existing ISs, which cause security states to move between mitigated, vulnerable, and compromised states. In previous work, we introduced the near real-time risk assessment using hidden Markov models (HMMs). This paper applies that theory to a prototype MatLab™ environment.
An acylic polyisoprenoid derivative, geranylgeranylacetone protects against visceral adiposity and insulin resistance in high-fat-fed mice
Authors: Adachi Hironori , Kondo Tatsuya , Ogawa Rei , Sasaki Kazunari , Morino-Koga Saori , Sakakida Michiharu , Kawashima Junji , Motoshima Hiroyuki , Furukawa Noboru , Tsuruzoe Kaku , Miyamura Nobuhiro , Kai Hirofumi , Araki Eiichi
Published: August 2010

Induction of heat shock protein (HSP)72 improves insulin resistance and obesity in diabetic animal models. Geranylgeranylacetone (GGA), known as an antiulcer drug, induces HSP72 and protects organs against several cellular stresses. This study investigated whether GGA administration would induce HSP72 in liver and render physiological protection against high-fat feeding in mice. A single and 4-wk oral administration of 200 mg/kg GGA was performed in high-fat diet (HFD)-fed mice. Metabolic parameters, cytokines, and gene expressions related to insulin signaling were evaluated. A single administration of GGA induced HSP72 in liver of normal chow-fed and HFD-fed mice. Insulin resistance after HFD was slightly ameliorated. Four weeks of GGA administration also increased HSP72 in liver and significantly improved insulin resistance and glucose homeostasis upon glucose challenge. Activation of c-jun NH2-terminal kinase (JNK) was attenuated, and insulin signaling was improved in the liver of HFD mice. Visceral adiposity was decreased in GGA-treated mice, accompanied by reduced leptin and increased adiponectin levels. GGA can be a novel therapeutic approach to treat metabolic syndrome as well as type 2 diabetes by improving insulin signaling and reducing adiposity. These beneficial effects of GGA could be mediated through HSP72 induction and JNK inactivation in the liver.
Selenocysteine, Pyrrolysine, and the Unique Energy Metabolism of Methanogenic Archaea
Authors: Rother Michael , Krzycki Joseph A.
Published: August 2010

Methanogenic archaea are a group of strictly anaerobic microorganisms characterized by their strict dependence on the process of methanogenesis for energy conservation. Among the archaea, they are also the only known group synthesizing proteins containing selenocysteine or pyrrolysine. All but one of the known archaeal pyrrolysine-containing and all but two of the confirmed archaeal selenocysteine-containing protein are involved in methanogenesis. Synthesis of these proteins proceeds through suppression of translational stop codons but otherwise the two systems are fundamentally different. This paper highlights these differences and summarizes the recent developments in selenocysteine- and pyrrolysine-related research on archaea and aims to put this knowledge into the context of their unique energy metabolism.
The Minimally Invasive Effect of Breast Approach Endoscopic Thyroidectomy: An Expert′s Experience
Authors: Zhang Wei , Jiang Zhi-guo , Jiang Dao-zhen , Zheng Xiang-min , Shen Hong-liang , Shan Cheng-xiang , Liu Sheng , Qiu Ming
Published: August 2010

We evaluated the invasiveness of breast approach endoscopic thyroidectomy (BAET) carried out by surgeon very experienced in this procedure. Twenty‐four patients who underwent BAET and 19 patients who underwent conventional thyroidectomy were the study population. Postoperative pain was assessed by a visual analog scale (VAS). The values 2, 12, and 24 h after surgery were significantly lower in the BAET group than those in the conventional group. Serum IL‐6 and CRP levels were measured by an ELISA preoperatively and at 2, 12, 24 and 48 h after operation. Their values increased significantly after both procedures when compared to preoperative levels with significant differences between the two groups detected at the 24‐hour and 48‐hour time points. Subjective and objective evidence supported the notion that BAET could become a minimally invasive procedure if the surgeon gained sufficient experience.
Therapeutic Strategies for SLE Involving Cytokines: Mechanism-Oriented Therapies Especially IFN- Targeting Gene Therapy
Authors: Hayashi Toshiharu
Published: August 2010

Systemic lupus erythematosus (SLE: lupus) is a chronic complicated autoimmune disease and pathogenesis is still unclear. However, key cytokines have been recognized. Interferon (IFN)- and also IFN are of particular importance. Depending on the concept that lupus is a helper T(Th)1 disease and that dendritic cells (DCs) determine the direction of lupus, balance shift of Th1/Th2 and immunogenic/tolerogenic DCs is reviewed for therapy. (IFN)-- and IFN--targeted (gene) therapies are introduced. These consist of Th1/Th2 balance shift and elimination of IFN- and IFN--related cytokines such as (interleukin)IL-12 and IL-18. Other approaches include suppression of immunocompetent cells, normalization of abnormal T-cell function, costimulation blockade, B lymphocyte stimulator (Blys) blockade, and suppression of nephritic kidney inflammation. Moreover, balance shift of IFN- and tumor necrosis factor (TNF)- together with regulatory T(Treg) cells are briefely introduced. Clinical application will be discussed.
Hepatitis C and Kidney Disease
Authors: Hayat Ashik , Mitwalli Ahmad
Published: August 2010

Multiple extrahepatic manifestations have been associated with chronic hepatitis C, the most important among them being cryoglobulinemia, glomerulonephritis, porphyria cutanea tarda, lichen planus, seronegative arthritis, and lymphoproliferative disorders as in the sudies of Bonkovsky and Mehta (2001) and El-Serag et al. (2002). We will discuss in this paper chronic hepatitis C- related kidney disease and course and management of patients with chronic hepatitis C in special circumstances like hemodialysis and kidney transplantation.
PPARαin Obesity: Sex Difference and Estrogen Involvement
Authors: Yoon Michung
Published: August 2010

Peroxisome proliferator-activated receptorα(PPARα) is a member of the steroid hormone receptor superfamily and is well known to act as the molecular target for lipid-lowering drugs of the fibrate family. At the molecular level, PPARαregulates the transcription of a number of genes critical for lipid and lipoprotein metabolism. PPARαactivators are further shown to reduce body weight gain and adiposity, at least in part, due to the increase of hepatic fatty acid oxidation and the decrease in levels of circulating triglycerides responsible for adipose cell hypertrophy and hyperplasia. However, these effects of the PPARαligand fenofibrate on obesity are regulated with sexual dimorphism and seem to be influenced by the presence of functioning ovaries, suggesting the involvement of ovarian steroids in the control of obesity by PPARα. In female ovariectomized mice, 17β-estradiol inhibits the actions of fenofibrate on obesity through its suppressive effects on the expression of PPARαtarget genes, and these processes may be mediated by inhibiting the coactivator recruitment of PPARα. Thus, it is likely that PPARαfunctions on obesity may be enhanced in estrogen-deficient states.
48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis
Authors: Zantour Baha , Sfar Mohamed Habib , Younes Samia , Alaya Wafa , Kamoun Mahdi , Mkaouar Emna , Jerbi Saida
Published: August 2010

A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family.
Impact of HIV/Aids on Child Mortality before the Highly Active Antiretroviral Therapy Era: A Study in Pointe-Noire, Republic of Congo
Authors: Lallemant Camille , Halembokaka Gaston , Baty Gaelle , Ngo-Giang-Huong Nicole , Barin Francis , Le Coeur Sophie
Published: August 2010

Few studies have documented the contribution of HIV/AIDS to mortality among children under 15 years. From June 30 to October 19, 2001, all child deaths (n=588) registered to the morgue and/or hospitals of the city of Pointe-Noire, Congo, were investigated using a combined approach including an interview of relatives andpostmortemclinical and biological HIV diagnosis. Twenty-one percent of children were HIV positive, while 10.5% of deaths were attributed to AIDS. The most common causes of death in HIV-infected children were pneumonia (30%), pyrexia (22%), diarrhoea (16%) and wasting syndrome (16%). Infant mortality rate was estimated 6.3 times higher in children born to HIV-infected mothers compared to HIV-uninfected mothers. This study provides a direct measure of HIV/AIDS as impact on child mortality using a rapid and reliable method. A significant number of deaths could be prevented if HIV infection was diagnosed earlier and infants were provided with antiretroviral treatments.