bluuebunny/crossref_metadata_2025 huggingface dataset:
An Exploratory Framework for Combining CFD Analysis and Evolutionary Optimization Into a Single Integrated Computational Environment
Authors: McCorkle Douglas S. , Bryden Kenneth M.
Published: June 2012

Several recent reports and workshops have identified integrated computational engineering as an emerging technology with the potential to transform engineering design. The goal is to integrate geometric models, analyses, simulations, optimization and decision-making tools, and all other aspects of the engineering process into a shared, interactive computer-generated environment that facilitates multidisciplinary and collaborative engineering. While integrated computational engineering environments can be constructed from scratch with high-level programming languages, the complexity of these proposed environments makes this type of approach prohibitively slow and expensive. Rather, a high-level software framework is needed to provide the user with the capability to construct an application in an intuitive manner using existing models and engineering tools with minimal programming. In this paper, we present an exploratory open source software framework that can be used to integrate the geometric models, computational fluid dynamics (CFD), and optimization tools needed for shape optimization of complex systems. This framework is demonstrated using the multiphase flow analysis of a complete coal transport system for an 800 MW pulverized coal power station. The framework uses engineering objects and three-dimensional visualization to enable the user to interactively design and optimize the performance of the coal transport system.
Modal Characterization of MEMS Switches via Output Only and Input/Output Identification Methods
Authors: Book Joel M. , Asokanthan Samuel F.
Published: June 2012

MEMS devices typically have moving or oscillating mechanical parts, and characterization of their dynamics, including their modal parameters, is highly desirable. This paper is concerned with experimental implementation of a Stochastic Subspace Identification (SSI) algorithm as well a base excitation based identification algorithm for experimental modal analysis of a micro-cantilever switch. A white noise signal applied to the built-in electrostatic actuator in the switches excited a response measured using microscanning Laser Doppler Vibrometry (LDV). In the case of identification via the SSI, only the output response was used while the base excitation based algorithm employed the input and the output signals. The modal parameters found using MACEC matched well with those predicted by theory, and the results obtained via the two experimental identification approaches are in good agreement, thus providing confidence in using the SSI approach for experimental modal analysis of MEMS structures.
Development of System for High Quality Wood Grain Design
Authors: Mori Takuya , Shibasaki Satoshi , Aoyama Hideki
Published: June 2012

Various approaches for generating woodgrain patterns using computer graphics have been proposed so far. However, it is difficult to reproduce real woodgrain patterns using such conventional methods. In this paper, a new approach for generating woodgrain patterns is proposed. Virtual trees are generated by simulating tree growth in consideration of environmental conditions. Moreover, fine tree tissues and reflection properties at the wood surface are modeled. By applying these modeled factors, more diverse and accurate woodgrain patterns can be generated. With this approach, various types of virtual trees can be obtained by changing growth conditions such as period and location of growth or form of tissue in trees without the need to reset complicated parameters of each tree species. After this, the virtual trees can be cut at arbitrary areas, thus allowing a variety of woodgrain patterns to be generated by easy parameter setup.
Experimental System and Validation for Energy-Based Characterization
Authors: Pan Jan Wei , Cheng Jinquan , Furukawa Tomonari , Iliopoulos Athanasios P. , Michopoulos John G.
Published: June 2012

This paper presents the experimental system and experimental validation of an energy-based characterization for the identification of elastic constants. Unlike the standard uniaxial testing machine, which uses a contact strain sensor such as extensometer, the developed system uses a non-contact optic sensor as an advantage to measure and derive external work and strain measurements for characterizing the elastic constants. To investigate the validity of the energy-based characterization, a graphical user interface and the experimental system were developed for the tensile tests of aluminum open-hole specimens. During the validation, the means and variances of the characterization results were analyzed. The reliability of its recursive estimation was further investigated by the convergence of covariance at every new measurement. Results showed that the recursive estimation allows identification of elastic constants of a test coupon at every acquisition of sensor data in an online manner. The identification of all the constants during deformation thus demonstrated the overall validity and efficiency of the energy-based characterization.
A Heterogeneous System-Level Power Macro-Modeling for Network-on-Chip Router
Authors: Wu Ning , Zhou Fang , Zhang Ying , Ge Fen
Published: June 2012

A heterogeneous macro-model for power extraction of the Network-on-Chip router at system level is proposed, with higher accuracy to overcome the shortcoming of existing architecture-level power simulators, which is aimed to evaluate the network performance rapidly and guide the communication structure design. Each module of the router is modeled by different methods according to different characteristics. The input/output ports, the routing algorithm and the crossbar switch are established by multiple linear regression because of their single data flow state. The arbiter is established based on BP neural network due to its numerous states. Several experiments with different traffic loads and input sequences are carried out to verify the power model. Experimental results show that our power model is higher speed over the gate-level simulation, and the average estimation error is 5.0%. As a case study, we use the proposed model to evaluate the performance of different core mappings for H.264 decoder in system-level low power design.
DVS Scheduling for Reducing Both Dynamic and Leakage Energy for (M,K)-Firm Real-Time Systems
Authors: Niu Linwei , Xie Yuanchang
Published: June 2012

While the dynamic voltage scaling (DVS) techniques are efficient in reducing the dynamic energy consumption for the processor, varying voltage alone becomes less effective for the overall power reduction as the leakage power is growing rapidly, i.e., five times per technical generation as predicted. On the other hand, Quality of Service (QoS) is also a primary concern in the development of today’s pervasive computing systems. In this paper, we study the problem of minimizing the overall energy consumption for soft real-time systems while ensuring the QoS-guarantee. In our research, the QoS requirements are deterministically quantified with the (m,k)-constraints, which require that at least m out of any k consecutive jobs of a task meet their deadlines. Two approaches are proposed in this paper. One statically determines the mandatory jobs that have to meet their deadlines in order to satisfy the (m,k)-constraints, and the other one does so dynamically. Moreover, we present efficient scheduling techniques to reduce the overall energy by procrastinating the execution of mandatory jobs and thus to merge the idle intervals. The simulation results demonstrate that our proposed techniques significantly outperformed previous research in both overall and idle energy reduction while providing the (m,k)-guarantee.
Tuple-Based Morphisms for E-Procurement Solutions
Authors: de Beca Miguel Ferro , Sarraipa Joao , Agostinho Carlos , Jardim-Goncalves Ricardo
Published: June 2012

The need to collaborate and establish partnerships to reach global business and markets is more common than ever amongst competitive companies, in particular, manufacturers. This need has required that businesses procure their supply needs on a global scale, thus forcing them to interact with a wide variety of potential suppliers coming from various countries. The advent of e-procurement has facilitated the exchange of procurement information amongst suppliers and their clients. However, due to the great variety of different sources of data models and semantics, businesses still face some difficulties exchanging vital information electronically and seamlessly. This situation is even worse with the advent of the evolution of the enterprise systems and applications, whose dynamics result in increasing the interoperability problem due to the continuous need for model adjustments and semantics harmonization. In order to contribute to a long term stable interoperable enterprise operating environment and facilitate the usage of existing and future e-procurement solutions, the authors propose the integration of traceability functionalities in information systems as a way to support such sustainability. Data, semantic, and structural mappings between partner enterprises should be modelled as tuples, and stored in a ‘Mediator Knowledge Base’ for communication support with reasoning capabilities, thus allowing to trace, monitor and support the stability maintenance of a system’s interoperable state. The mapping stored also contains an ATL code expression, which with the aid of model transformation tools, can be utilized to perform the mapping between two different enterprise data models, thus facilitating future automation.
Experimental Considerations in Single Asperity Interactions
Authors: Burbridge Daniel J. , Gordeev Sergey N.
Published: June 2012

In the interest of understanding contact mechanics, friction and wear processes where plastic deformation occurs between rough surfaces, significant effort has and continues to be applied to understand single asperity elastic-plastic contacts. The main tools used in obtaining experimental data with which to inform and validate simulation methods in this area of study are nano and micro indenters. This article presents some of the less commonly considered phenomena which may affect the interpretation of experimental data from such apparatus. The interpretation of AFM pull off data is briefly discussed and invasive effects of electron imaging are highlighted.
The Influence of Initial Residual Stress State on the Steady State Behaviour of Cyclically Loaded Coupled Contacts
Authors: Flicek Robert , Dini Daniele , Hills David A.
Published: June 2012

The Melan’s shakedown theorem applies to uncoupled frictional contact problems, but is known formally not to apply in the case of coupled contacts. In this paper we look at two example coupled problems (one very strongly coupled) in detail and show that, in fact, for these specific cases, shakedown does occur for a range of initial load states.
Compositional depth profiling of TaCN thin films
Authors: Adelmann Christoph , Conard Thierry , Franquet Alexis , Brijs Bert , Munnik Frans , Burgess Simon , Witters Thomas , Meersschaut Johan , Kittl Jorge A. , Vandervorst Wilfried , Van Elshocht Sven
Published: June 2012

The composition profiling of thin TaCN films was studied. For the composition profile determination using x-ray photoemission spectrometry (XPS) in combination with Ar sputtering, preferential sputtering effects of N with respect to Ta and C were found to lead to inaccurate elemental concentrations. Sputter yield calculations for the given experimental conditions allowed for the correction of a part of the error, leading to fair accuracy by reference-free measurements. Further improvement of the accuracy was demonstrated by the calibration of the XPS compositions against elastic recoil detection analysis (ERDA) results. For Auger electron spectrometry (AES) in combination with Ar sputtering, accurate results required the calibration against ERDA. Both XPS and AES allowed for a reliable and accurate determination of the compositional profiles of TaCN-based thin films after calibration. Time-of-flight secondary-ion mass spectrometry was also used to assess the composition of the TaCN films. However, the analysis was hampered by large matrix effects due to small unintentional oxygen contents in the films. Energy-dispersive x-ray spectrometry is also discussed, and it is shown that an accurate reference-free measurement of the average film concentration can be achieved.
Indium and impurity incorporation in InGaN films on polar, nonpolar, and semipolar GaN orientations grown by ammonia molecular beam epitaxy
Authors: Browne David A. , Young Erin C. , Lang Jordan R. , Hurni Christophe A. , Speck James S.
Published: June 2012

The effects of NH3 flow, group III flux, and substrate growth temperature on indium incorporation and surface morphology have been investigated for bulk InGaN films grown by ammonia molecular beam epitaxy. The incorporation of unintentional impurity elements (H, C, O) in InGaN films was studied as a function of growth temperature for growth on polar (0001) GaN on sapphire templates, nonpolar (101¯0) bulk GaN, and semipolar (112¯2), (202¯1) bulk GaN substrates. Enhanced indium incorporation was observed on both (101¯0) and (202¯1) surfaces relative to c-plane, while reduced indium incorporation was observed on (112¯2) for co-loaded conditions. Indium incorporation was observed to increase with decreasing growth temperature for all planes, while being relatively unaffected by the group III flux rates for a 1:1 Ga:In ratio. Indium incorporation was found to increase at the expense of a decreased growth rate for higher ammonia flows; however, smooth surface morphology was consistently observed for growth on semipolar orientations. Increased concentrations of oxygen and hydrogen were observed on semipolar and nonpolar orientations with a clear trend of increased hydrogen incorporation with indium content.
Mucus-Penetrating Nanoparticles for Vaginal Drug Delivery Protect Against Herpes Simplex Virus
Authors: Ensign Laura M. , Tang Benjamin C. , Wang Ying-Ying , Tse Terence A. , Hoen Timothy , Cone Richard , Hanes Justin
Published: June 2012

Mucus-penetrating particles improve drug delivery to the mucosal surface of the mouse vagina and deliver acyclovir for enhanced protection against vaginal herpes infection in mice.
Autoimmune Diabetes Inflames the Heart
Authors: Eckel Robert H. , Eisenbarth George S.
Published: June 2012

Patients with type 1 diabetes tend to suffer subsequent and persistent inflammation of cardiac tissue after a heart attack.
Positive Regulation of Leptospira interrogans kdp Expression by KdpE as Demonstrated with a Novel β-Galactosidase Reporter in Leptospira biflexa
Authors: Matsunaga James , Coutinho Mariana L.
Published: June 2012

Leptospirosis is a potentially deadly zoonotic disease that afflicts humans and animals.Leptospira interrogans, the predominant agent of leptospirosis, encounters diverse conditions as it proceeds through its life cycle, which includes stages inside and outside the host. Unfortunately, the number of genetic tools available for examining the regulation of gene expression inL. interrogansis limited. Consequently, little is known about the genetic circuits that control gene expression inLeptospira. To better understand the regulation of leptospiral gene expression, theL. interrogans kdplocus, encoding homologs of the P-type ATPase KdpABC potassium transporter with their KdpD sensors and KdpE response regulators, was selected for analysis. We showed that akdpEmutation inL. interrogansprevented the increase inkdpABCmRNA levels observed in the wild-typeL. interrogansstrain when external potassium levels were low. To confirm that KdpE was a positive regulator ofkdpABCtranscription, we developed a novel approach for constructing chromosomal genetic fusions to the endogenousbgaL(β-galactosidase) gene of the nonpathogenLeptospira biflexa. We demonstrated positive regulation of akdpA′-bgaLfusion inL. biflexaby theL. interrogansKdpE response regulator. A controllipL32′-bgaLfusion was not regulated by KdpE. These results demonstrate the utility of genetic fusions to thebgaLgene ofL. biflexafor examining leptospiral gene regulation.
New Molecular Quantitative PCR Assay for Detection of Host-Specific Bifidobacteriaceae Suitable for Microbial Source Tracking
Authors: Gómez-Doñate Marta , Ballesté Elisenda , Muniesa Maite , Blanch Anicet R.
Published: June 2012

Bifidobacterium
spp. belong to the commensal intestinal microbiota of warm-blooded animals. Some strains of
Bifidobacterium
show host specificity and have thus been proposed as host-specific targets to determine the origin of fecal pollution. Most strains have been used in microbial-source-tracking (MST) studies based on culture-dependent methods. Although some of these approaches have proved very useful, the low prevalence of culturable
Bifidobacterium
strains in the environment means that molecular culture-independent procedures could provide practical applications for MST. Reported here is a set of common primers and four
Bifidobacterium
sp. host-associated (human, cattle, pig, and poultry) probes for quantitative-PCR (qPCR) assessment of fecal source tracking. This set was tested using 25 water samples of diverse origin: urban sewage samples, wastewater from four abattoirs (porcine, bovine, and poultry), and water from a river with a low pollution load. The selected sequences showed a high degree of host specificity. There were no cross-reactions between the qPCR assays specific for each origin and samples from different fecal origins. On the basis of the findings, it was concluded that the host-specific qPCRs are sufficiently robust to be applied in environmental MST studies.
Conjugal Transfer of Polychlorinated Biphenyl/Biphenyl Degradation Genes in Acidovorax sp. Strain KKS102, Which Are Located on an Integrative and Conjugative Element
Authors: Ohtsubo Yoshiyuki , Ishibashi Yoko , Naganawa Hideaki , Hirokawa Satoshi , Atobe Satomi , Nagata Yuji , Tsuda Masataka
Published: June 2012

A polychlorinated biphenyl (PCB)/biphenyl degradation gene cluster in
Acidovorax
sp. strain KKS102, which is very similar to that in Tn
4371
from
Cupriavidus oxalaticus
A5, was transferred to several proteobacterial strains by conjugation. The mobilized DNA fragment consisted of 61,807 bp and carried genes for mating-pair formation (
mpf
), DNA transfer (
dtr
), integrase (
int
), and replication-partition proteins (
rep
-
parAB
). In the transconjugants, transferred DNA was integrated at ATTGCATCAG or similar sequences. The circular-form integrative and conjugative element (ICE) was detected by PCR, and quantitative PCR analyses revealed that, in KKS102 cells, the ratio of the circular form to the integrated form was very low (approximately 10
−5
). The circular form was not detected in a mutant of the
int
gene, which was located at the extreme left and transcribed in the inward direction, and the level of
int
transcriptional activity was much higher in the circular form than in the integrated form. These findings clearly demonstrated that the genes for PCB/biphenyl degradation in KKS102 cells are located on an ICE, which was named ICE
KKS102
4677
. Comparisons of similar ICE-like elements collected from the public database suggested that those of beta- and gammaproteobacteria were distinguishable from other ICE-like elements, including those in alphaproteobacteria, with respect to the gene composition and gene organization.
The Extracytoplasmic Function Sigma Factor σ
S
Protects against both Intracellular and Extracytoplasmic Stresses in Staphylococcus aureus
Authors: Miller Halie K. , Carroll Ronan K. , Burda Whittney N. , Krute Christina N. , Davenport Jessica E. , Shaw Lindsey N.
Published: June 2012

Previously we identified a novel component of the
Staphylococcus aureus
regulatory network, an
e
xtra
c
ytoplasmic
f
unction σ-factor, σ
S
, involved in stress response and disease causation. Here we present additional characterization of σ
S
, demonstrating a role for it in protection against DNA damage, cell wall disruption, and interaction with components of the innate immune system. Promoter mapping reveals the existence of three unique
sigS
start sites, one of which appears to be subject to autoregulation. Transcriptional profiling revealed that
sigS
expression remains low in a number of
S. aureus
wild types but is upregulated in the highly mutated strain RN4220. Further analysis demonstrates that
sigS
expression is inducible upon exposure to a variety of chemical stressors that elicit DNA damage, including methyl methanesulfonate and ciprofloxacin, as well as those that disrupt cell wall stability, such as ampicillin and oxacillin. Significantly, expression of
sigS
is highly induced during growth in serum and upon phagocytosis by RAW 264.7 murine macrophage-like cells. Phenotypically, σ
S
mutants display sensitivity to a broad range of DNA-damaging agents and cell wall-targeting antibiotics. Furthermore, the survivability of σ
S
mutants is strongly impacted during challenge by components of the innate immune system. Collectively, our data suggest that σ
S
likely serves dual functions within the
S. aureus
cell, protecting against both cytoplasmic and extracytoplasmic stresses. This further argues for its important, and perhaps novel, role in the
S. aureus
stress and virulence responses.
Synthesis of Lipoteichoic Acids in Bacillus anthracis
Authors: Garufi Gabriella , Hendrickx Antoni P. , Beeri Karen , Kern Justin W. , Sharma Anshika , Richter Stefan G. , Schneewind Olaf , Missiakas Dominique
Published: June 2012

Lipoteichoic acid (LTA), a glycerol phosphate polymer, is a component of the envelope of Gram-positive bacteria that has hitherto not been identified in
Bacillus anthracis
, the causative agent of anthrax. LTA synthesis in
Staphylococcus aureus
and other microbes is catalyzed by the product of the
ltaS
gene, a membrane protein that polymerizes polyglycerol phosphate from phosphatidyl glycerol. Here we identified four
ltaS
homologues, designated
ltaS1
to -
4
, in the genome of
Bacillus anthracis
. Polyglycerol phosphate-specific monoclonal antibodies were used to detect LTA in the envelope of
B. anthracis
strain Sterne (pXO1
+
pXO2
−
) vegetative forms.
B. anthracis
mutants lacking
ltaS1
,
ltaS2
,
ltaS3
, or
ltaS4
did not display defects in growth or LTA synthesis. In contrast,
B. anthracis
strains lacking both
ltaS1
and
ltaS2
were unable to synthesize LTA and exhibited reduced viability, altered envelope morphology, aberrant separation of vegetative forms, and decreased sporulation efficiency. Expression of
ltaS1
or
ltaS2
alone in
B. anthracis
as well as in other microbes was sufficient for polyglycerol phosphate synthesis. Thus, similar to
S. aureus
,
B. anthracis
employs LtaS enzymes to synthesize LTA, an envelope component that promotes bacterial growth and cell division.
Serum (1→3)-β-
d
-Glucan Measurement in Coccidioidomycosis
Authors: Thompson George R. , Bays Derek J. , Johnson Suzanne M. , Cohen Stuart H. , Pappagianis Demosthenes , Finkelman Malcolm A.
Published: June 2012

The serum (1→3)-β-
d
-glucan assay has emerged as an important diagnostic test for invasive fungal disease. The utility of this assay in coccidioidomycosis has not been previously studied. Using a cutoff value of ≥80 pg/ml, we found the sensitivity (43.9%), specificity (91.1%), positive predictive value (81.8%), and negative predictive value (64.1%) to be similar to those of the assay in diagnosing other invasive mycoses.
From Quellung to Multiplex PCR, and Back When Needed, in Pneumococcal Serotyping
Authors: Siira Lotta , Kaijalainen Tarja , Lambertsen Lotte , Nahm Moon H. , Toropainen Maija , Virolainen Anni
Published: June 2012

All currently available vaccines against
Streptococcus pneumoniae
are based on selections of the over 90 different serotypes, which underlines the importance of serotyping for surveillance and vaccine efficacy monitoring. In this study, we modified and validated a PCR-based scheme for deducing the serotypes of the invasive pneumococci isolated in Finland. For validation, 170 isolates were serotyped using the new protocol with six sequential multiplex PCRs for the deduction of serotypes, supplemented with Quellung testing when needed. The results were compared with those obtained by traditional serotyping methods. We found that 98.8% (168/170) of the isolates were correctly serotyped by the new protocol. Subsequently, the scheme was taken into regular use for serotyping the invasive pneumococci isolated in Finland for serotype-specific surveillance purposes and has been applied in the serotyping of more than 1,500 invasive isolates so far. The sequential multiplex PCRs (mPCRs) have given a result for over 99% of the isolates and allowed us to both handle samples in bulk and noticeably reduce the cost of reagents. While serotyping primarily by PCR is precise and effective, Quellung testing remains the most reliable way to discover possible discrepancies between the DNA deduced and the phenotypic serotype of an isolate. Since implementing the protocol for regular use, two serotype 19F PCR-positive isolates were found to be serotype 19A by the Quellung reaction. While a rare occurrence, this is an important observation, which prompted a revision of our serotyping protocol to prevent possible underreporting of serotype 19A, a potential replacement serotype following large-scale vaccination.
Francisella novicida Bacteremia after a Near-Drowning Accident
Authors: Brett Meghan , Doppalapudi Avanthi , Respicio-Kingry Laurel B. , Myers Debra , Husband Brigitte , Pollard Kerry , Mead Paul , Petersen Jeannine M. , Whitener Cynthia J.
Published: June 2012

We describe a rare case of
Francisella novicida
bacteremia following a near-drowning event in seawater. We highlight the challenges associated with laboratory identification of
F. novicida
and differences in the epidemiology of
F. novicida
and
Francisella tularensis
infections.
Is Real-Time PCR Better than Conventional PCR for Mycobacterium tuberculosis Complex Detection in Clinical Samples?
Authors: Tortoli Enrico , Urbano Pasquale , Marcelli Fiorella , Simonetti Tullia M. , Cirillo Daniela M.
Published: June 2012

Cobas Amplicor MTB and later Cobas TaqMan MTB were used to test a very large series of consecutive specimens received for tuberculosis diagnosis. Performance parameters were estimated and compared overall and for separate specimen categories. Both systems showed excellent specificity, and that of TaqMan was the higher. The sensitivities were similar but satisfactory only with respiratory specimens and smear-positive samples.
THE CASIMIR EFFECT FOR GENERALIZED PISTON GEOMETRIES
Authors: FUCCI GUGLIELMO , KIRSTEN KLAUS
Published: June 2012

In this paper we study the Casimir energy and force for generalized pistons constructed from warped product manifolds of the type I ×f N where I = [a, b] is an interval of the real line and N is a smooth compact Riemannian manifold either with or without boundary. The piston geometry is obtained by dividing the warped product manifold into two regions separated by the cross section positioned at R ∈ (a, b). By exploiting zeta function regularization techniques we provide formulas for the Casimir energy and force involving the arbitrary warping function f and base manifold N.
STRONG-FIELD QED AND HIGH-POWER LASERS
Authors: HEINZL THOMAS
Published: June 2012

This contribution presents an overview of fundamental QED processes in the presence of an external field produced by an ultra-intense laser. The discussion focusses on the basic intensity effects on vacuum polarisation and the prospects for their observation. Some historical remarks are added where appropriate.
GENERALIZED (LAG, ANTICIPATED AND COMPLETE) PROJECTIVE SYNCHRONIZATION IN TWO NONIDENTICAL CHAOTIC SYSTEMS WITH UNKNOWN PARAMETERS
Authors: WANG XINGYUAN , WANG LULU , LIN DA
Published: June 2012

In this paper, a generalized (lag, anticipated and complete) projective synchronization for a general class of chaotic systems is defined. A systematic, powerful and concrete scheme is developed to investigate the generalized (lag, anticipated and complete) projective synchronization between the drive system and response system based on the adaptive control method and feedback control approach. The hyperchaotic Chen system and hyperchaotic Lorenz system are chosen to illustrate the proposed scheme. Numerical simulations are provided to show the effectiveness of the proposed schemes. In addition, the scheme can also be extended to research generalized (lag, anticipated and complete) projective synchronization between nonidentical discrete-time chaotic systems.
GAME THEORETIC ANALYSIS OF TWO-PERIOD-DEPENDENT DEGRADED MULTISTATE RELIABILITY SYSTEMS
Authors: HAUSKEN KJELL
Published: June 2012

A system of two components is analyzed as a two-period game. After period 1 the system can be fully operational, in two states of intermediate degradation, or fail. Analogously to changing failure rates in dependent systems analyzed with Markov analysis, unit costs of defense and attack, and contest intensities, change in period 2. As the values of the two intermediate states increase from zero which gives the series system, towards their maxima which gives the parallel system, the defender becomes more advantaged, and the attacker more disadvantaged. Simulations illustrate the players' efforts in the two time periods and utilities dependent on parametric changes. The defender withdraws from defending the system when the values of both degraded states are very low. The attacker withdraws from attacking the system when the values of both degraded states are very high. In the benchmark case the defender prefers the one-period game and the attacker prefers the two-period game, but if the attacker's unit cost of attack is large for one component, and the value of the degraded system with this component operational is above a low value, the defender prefers the two-period game to obtain high utility in period 2 against a weak attacker. When the values of the degraded states are above certain low values, the players exert higher efforts in period 1 of a two-period game than in a one-period game, as investments into the future to ensure high versus low reliability in period 2.
NONCOOPERATIVE GAMES FROM TU GAMES WITH INFORMATION COST
Authors: BRIATA FEDERICA
Published: June 2012

From a special class of TU games with information cost, given by the problem of sharing the costs of facilities among users, we build a noncooperative game in which every player asks for the assessment of whom the users are. We analyze two models, "naming" game and majority decision game: the existence of equilibria is assured since the games are binary and symmetric, and then potential games. Since the games are ex-ante fair, we search a proposal to compensate for ex-post injustice.
STRATEGIC DELEGATION IN A STACKELBERG GAME WITH MULTIPLE STAGES
Authors: LEKEAS PARASKEVAS V. , STAMATOPOULOS GIORGOS
Published: June 2012

We analyze strategic delegation in a Stackelberg model with an arbitrary number, n, of firms. We show that n-1 firms delegate their production decisions and only one firm (the one whose manager is the first mover) does not. The later a manager commits to a quantity, the higher his incentive rate. Letting [Formula: see text] denote the equilibrium payoff of the firm whose manager commits in the ith stage, we show that [Formula: see text]. We also compare the delegation outcome of our game with that of a corresponding Cournot oligopoly and show that managers who commit late (early) are given higher (lower) incentive rates than managers in the Cournot market.
AUCTIONS, REAL OPTIONS VALUATION, AND PRIVATIZATION
Authors: EL-SHAZLY ALAA
Published: June 2012

This article studies competitive bidding by strategic investors to buy enterprises that are being privatized through sealed-bid auctions. The bidders use a real options approach to enterprise valuation that accounts for asset quality given their private information. It is shown that the optimal bidding strategy under first-price sealed-bid auctions defines a Bayesian Nash equilibrium in which each strategic investor bids only a fraction of its prior valuation and competition decreases the bidder's profit margin. The greater the transparency and information disclosure on asset quality, the higher the seller's expected receipts will be.
INDEPENDENCE OF IRRELEVANT ALTERNATIVES AND FUZZY ARROW'S THEOREM
Authors: MORDESON JOHN N. , GIBILISCO MICHAEL B. , CLARK TERRY D.
Published: June 2012

The literature involving fuzzy Arrow results uses the same independence of irrelevant alternatives condition. We introduce three other types of independence of irrelevant alternative conditions and show that they can be profitably used in the examination of Arrow's theorem. We also generalize some known nondictatorship results. One known fuzzy aggregation rule that is nondictatorial is the average of the individual preferences. We show that a weighted average is also nondictatorial. Moreover, it is not an automorphic image of the ordinary average, which demonstrates that we have proposed a framework unique from the present known results.
THE APPLICATION OF THE BrilLanCe SERIES SCINTILLATION DETECTOR IN THE SPECTROMETER OF NEUTRAL PARTICLES FOR THE SATELLITE EXPERIMENT ZINA-NT
Authors: ARKHANGELSKAJA IRENE V. , ARKHANGELSKY ANDREY I. , BATISCHEV ALEXEY.G , GALPER ARKADY M. , KONDRATYEVA NATALYA V. , NAUMOV PETR YU.
Published: June 2012

Spectrometric detector complex ZINA-NT is intended to study a radiation conditions onboard satellite and characteristics of hard X-ray and gamma-ray fluxes from GRB, solar flares and to detect other non-stationary fluxes of cosmic gamma-rays. The advantages for using of this new detector for modification of present neutral particles detector on the base of CsI(Tl) are discussed. Scintillation detectors based on BrilLanCe series crystal have got very small lighting time, an excellent energy resolution and light output, more intensive than devices based on CsI(Tl). Using of BrilLanCe series crystal instead of CsI(Tl) ones allows to detect terrestrial gamma flashes (TGF), gamma ray bursts (GRB) and solar flares with smaller time durations and intensities. Moreover, the counts rate linearity region of BrilLanCe detectors is extended up to 106 s-1 and it allows to observe a very intensive events. So, the using of such type of detector permits us the possibility to separate gamma-quanta and neutrons on the timescales less than 50 microseconds.
NEUTRINOLESS DOUBLE BETA DECAY
Authors: CREMONESI OLIVIERO
Published: June 2012

Neutrinoless double beta decay (ββ(0ν)) is presently the only practical tool for probing the character of neutrinos. In case neutrinos are Majorana particles ββ(0ν) can provide also fundamental informations on their absolute mass scale. The present status of experiments searching for ββ(0ν) is reviewed and the most relevant results discussed. A possibility to observe ββ(0ν) at a neutrino mass scale in the range 10-50 meV looks possible according to our present knowledge of the neutrino masses and mixing parameters. A review of the future projects and of the most relevant parameters contributing to the experimental sensitivity iss finally outlined.
ABOUT THE STATISTICAL PROPERTIES OF COSMOLOGICAL BILLIARDS
Authors: DAMOUR THIBAULT , LECIAN ORCHIDEA MARIA
Published: June 2012

We summarize some recent progress in the understanding of the statistical properties of cosmological billiards.
ON THE ORIGIN OF HIGH ENERGY GAMMA-RAYS FROM GIANT RADIO LOBES CENTARUS A
Authors: SAHAKYAN N.
Published: June 2012

Recently Fermi LAT collaboration reported the detection of high energy gamma-ray signal from giant lobes of the radio galaxy Centaurus A. We discuss the origin of this radiation and the possible radiation mechanisms, including inverse-Compton scattering of low energy photons and interaction of relativistic protons with the ambient low density plasma.
NON-THERMAL PHENOMENA IN GALAXY CLUSTERS
Authors: FERRARI CHIARA
Published: June 2012

The existence of cosmic rays and weak magnetic fields in the intracluster volume has been well proven by deep radio observations of galaxy clusters. However a detailed physical characterization of the non-thermal component of large scale-structures, relevant for high-precision cosmology, is still missing. I will show the importance of combining numerical and theoretical works with cluster observations by a new-generation of radio, Gamma- and X-ray instruments.
HIGH ENERGETIC GAMMA RAY BURSTS AND THEIR SPECTRAL PROPERTIES WITHIN THE FIRESHELL MODEL
Authors: PATRICELLI B. , BERNARDINI M.G. , BIANCO C.L. , CAITO L. , DE BARROS G. , IZZO L. , RUFFINI R. , VERESHCHAGIN G.
Published: June 2012

The analysis of various Gamma Ray Bursts (GRBs) characterized by an isotropic energy Eiso ≲ 1053 ergs within the fireshell model has shown how that the observed N(E) spectrum of their prompt emission can be reproduced in a satisfactory way by assuming a thermal spectrum in the comoving frame of the fireshell. Nevertheless, from the study of higher energetic bursts (Eiso ≳ 1054 ergs ) such as, for example, GRB 080319B, some discrepancies between the numerical simulations and the observational data have been observed. We investigate a different spectrum of photons in the comoving frame of the fireshell in order to better reproduce the spectral properties of GRB prompt emission within the fireshell model. We introduce a phenomenologically modified comoving thermal spectrum: a spectrum characterized by a different asymptotic low energy slope with respect to the thermal one. We test this spectrum by comparing the numerical simulations with the observed prompt emission spectra of various GRBs; we present, as an exaple, the case of GRB 080319B.
TOWARDS A UNIFIED DEFINITION OF SOLAR LIMB DURING CENTRAL ECLIPSES AND DAILY TRANSITS
Authors: SIGISMONDI COSTANTINO , RAPONI ANDREA , BAZIN CYRIL , NUGENT RICHARD
Published: June 2012

The diameter of the Sun has been measured using Baily's beads during central eclipses, observed with portable telescopes. A blend of tiny emission lines produced in the first several hundred kilometers above the photosphere gives a light signal which prolonges the light curves of the beads. The simple criterion of light OFF/ON adopted in the previous approaches to define the timing of photosphere's disappearance/reappearance is modified. The technique of the limb darkening function reconstruction from the Baily's beads light curves is introduced here.
ON A COMMON MISUNDERSTANDING OF THE BIRKHOFF THEOREM AND LIGHT DEFLECTION CALCULATION: GENERALIZED SHAPIRO DELAY AND ITS POSSIBLE LABORATORY TEST
Authors: ZHANG SHUANG-NAN , YI SHUXU
Published: June 2012

In Newtonian gravity (NG) it is known that the gravitational field anywhere inside a spherically symmetric distribution of mass is determined only by the enclosed mass. This is also widely believed to be true in general relativity (GR), and the Birkhoff theorem is often invoked to support this analogy between NG and GR. Here we show that such an understanding of the Birkhoff theorem is incorrect and leads to erroneous calculations of light deflection and delay time through matter. The correct metric, matching continuously to the location of an external observer, is determined both by the enclosed mass and mass distribution outside. The effect of the outside mass is to make the interior clock run slower, i.e., a slower speed of light for external observer. We also discuss the relations and differences between NG and GR, in light of the results we obtained in this Lettework. Finally we discuss the Generalized Shapiro delay, caused by the outside mass, and its possible laboratory test.
A Conversation with Haldor Topsøe
Authors: Topsøe Haldor , Mavrikakis Manos
Published: June 2012

Haldor Topsøe was born in Copenhagen, Denmark, in 1913. He studied chemical engineering at the Technical University of Denmark (DTU). In 1940, he founded the company Haldor Topsøe, which has become one of the most successful companies in the field of heterogeneous catalysis. The company develops and markets catalysts and processes for petroleum refining, air-pollution control, synthesis gas production, ammonia and methanol production and solid oxide fuel cells. The company Haldor Topsøe is also a leader in the production and state-of-the-art scientific characterization of new catalysts. Dr. Topsøe is currently the sole owner of the company. He has written numerous articles on ammonia synthesis, catalysis, and energy questions. He is the author of several books on economics. Dr. Topsøe has received numerous awards, including honorary doctorates from Aarhus University, DTU, and the Chalmers University in Sweden; the Gold Medal from the Royal Academy of Sciences; the Hoover Medal for his technical abilities and entrepreneurship; and the Grove Memorial Medal for Advances in Fuel Cell Technology. Topsøe is a member of the Danish and the Swedish Academies of Technical Sciences and of the U.S. National Academy of Engineering.

The following interview was conducted on August 16, 2010.

–Manos Mavrikakis
Nature Versus Nurture: Developing Enzymes That Function Under Extreme Conditions
Authors: Liszka Michael J. , Clark Melinda E. , Schneider Elizabeth , Clark Douglas S.
Published: June 2012

Many industrial processes used to produce chemicals and pharmaceuticals would benefit from enzymes that function under extreme conditions. Enzymes from extremophilic microorganisms have evolved to function in a variety of extreme environments, and bioprospecting for these microorganisms has led to the discovery of new enzymes with high tolerance to nonnatural conditions. However, bioprospecting is inherently limited by the diversity of enzymes evolved by nature. Protein engineering has also been successful in generating extremophilic enzymes by both rational mutagenesis and directed evolution, but screening for activity under extreme conditions can be difficult. This review examines the emerging synergy between bioprospecting and protein engineering in developing extremophilic enzymes. Specific topics include unnatural industrial conditions relevant to biocatalysis, biophysical properties of extremophilic enzymes, and industrially relevant extremophilic enzymes found either in nature or through protein engineering.
Endogenous leptin receptor signaling in the medial nucleus tractus solitarius affects meal size and potentiates intestinal satiation signals
Authors: Kanoski Scott E. , Zhao Shiru , Guarnieri Douglas J. , DiLeone Ralph J. , Yan Jianqun , De Jonghe Bart C. , Bence Kendra K. , Hayes Matthew R. , Grill Harvey J.
Published: June 2012

Leptin receptor (LepRb) signaling in the hindbrain is required for energy balance control. Yet the specific hindbrain neurons and the behavioral processes mediating energy balance control by hindbrain leptin signaling are unknown. Studies here employ genetic [adeno-associated virally mediated RNA interference (AAV-RNAi)] and pharmacological methodologies to specify the neurons and the mechanisms through which hindbrain LepRb signaling contributes to the control of food intake. Results show that AAV-RNAi-mediated LepRb knockdown targeting a region encompassing the mNTS and area postrema (AP) (mNTS/AP LepRbKD) increases overall cumulative food intake by increasing the size of spontaneous meals. Other results show that pharmacological hindbrain leptin delivery and RNAi-mediated mNTS/AP LepRb knockdown increased and decreased the intake-suppressive effects of intraduodenal nutrient infusion, respectively. These meal size and intestinally derived signal amplification effects are likely mediated by LepRb signaling in the mNTS and not the AP, since 4th icv and mNTS parenchymal leptin (0.5 μg) administration reduced food intake, whereas this dose did not influence food intake when injected into the AP. Overall, these findings deepen the understanding of the distributed neuronal systems and behavioral mechanisms that mediate the effects of leptin receptor signaling on the control of food intake.
Different expression of adrenoceptors and GRKs in the human myocardium depends on heart failure ethiology and correlates to clinical variables
Authors: Montó Fermí , Oliver Eduardo , Vicente Diana , Rueda Joaquín , Agüero Jaime , Almenar Luis , Ivorra Maria Dolores , Barettino Domingo , D'Ocon Pilar
Published: June 2012

Downregulation of β1- adrenergic receptors (β1-ARs) and increased expression/function of G-protein-coupled receptor kinase 2 (GRK2) have been observed in human heart failure, but changes in expression of other ARs and GRKs have not been established. Another unresolved question is the incidence of these compensatory mechanisms depending on heart failure etiology and treatment. To analyze these questions, we quantified the mRNA/protein expressions of six ARs (α1A, α1B, α1D, β1, β2, and β3) and three GRKs (GRK2, GRK3, and GRK5) in left (LV) and right ventricle (RV) from four donors, 10 patients with ischemic cardiomyopathy (IC), 14 patients with dilated cardiomyopathy (DC), and 10 patients with nonischemic, nondilated cardiopathies (NINDC). We correlated the changes in the expressions of ARs and GRKs with clinical variables such as left ventricular ejection fraction (LVEF) and left ventricular end-systolic and left ventricular end-diastolic diameter (LVESD and LVEDD, respectively). The main findings were 1) the expression of the α1A-AR in the LV positively correlates with LVEF; 2) the expression of GRK3 and GRK5 inversely correlates with LVESD and LVEDD, supporting previous observations about a protective role for both kinases in failing hearts; and 3) β1-AR expression is downregulated in the LV and RV of IC, in the LV of DC, and in the RV of NINDC. This difference, better than an increased expression of GRK2 (not observed in IC), determines the lower LVEF in IC and DC vs. NINDC.
Critical role for integrin-β4 in the attenuation of murine acute lung injury by simvastatin
Authors: Chen Weiguo , Sammani Saad , Mitra Sumegha , Ma Shwu Fan , Garcia Joe G. N. , Jacobson Jeffrey R.
Published: June 2012

The statins are a class of 3-hydroxy-3-methylglutaryl-coenzyme A-reductase inhibitors that are recognized to have pleiotropic properties. We previously reported the attenuation of LPS-induced murine acute lung injury (ALI) by simvastatin in vivo and identified relevant effects of simvastatin on endothelial cell (EC) signaling, activation, and barrier function in vitro. In particular, simvastatin induces the upregulation of integrin-β4, which in turn inhibits EC inflammatory responses via attenuation of MAPK signaling. The role of integrin-β4 in murine ALI protection by simvastatin, however, is unknown. We initially confirmed a time- and dose-dependent effect of simvastatin on increased integrin-β4 mRNA expression in human lung EC with peak protein expression evident at 16 h. Subsequently, reciprocal immunoprecipitation demonstrated an attenuation of LPS-induced integrin-β4 tyrosine phosphorylation by simvastatin (5 μM, 16 h). Increased expression of EC inflammatory cytokines [IL-6, IL-8, monocyte chemoattractant protein (MCP)-1, regulated on activation normal T cell expressed and secreted (RANTES)] by LPS (500 ng/ml, 4 h) was also significantly attenuated by simvastatin pretreatment (5 μM, 16 h), but this effect was reversed by cotreatment with an integrin-β4-blocking antibody. Finally, although simvastatin (20 mg/kg) conferred significant protection in murine ALI as evidenced by decreased bronchoalveolar lavage fluid cell counts, protein, inflammatory cytokines (IL-6, IL-1β, MCP-1, RANTES), decreased Evans blue dye albumin extravasation in lung tissue, and changes on lung histology, these effects were reversed by the integrin-β4-blocking antibody (IV, 1 mg/kg, 2 h before LPS). These findings support integrin-β4 as an important mediator of ALI protection by simvastatin and implicate signaling by integrin-β4 as a novel therapeutic target in patients with ALI.