bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypertension as an Underlying Factor in Heart Failure With Preserved Ejection Fraction
Authors: Volpe Massimo , McKelvie Robert , Drexler Helmut
Published: January 2010

J Clin Hypertens (Greenwich).

The unique pathophysiology of heart failure with a preserved ejection fraction (HF‐PEF) and the involvement of hypertension in its development are only poorly understood. The upregulation of the renin‐angiotensin‐aldosterone system (RAAS) has been identified as a key pathologic pathway contributing to fibrosis, cardiomyocyte abnormalities, inflammation, and endothelial dysfunction, all of which have been implicated in the progression of hypertension to HF‐PEF. In addition, pharmacologic inhibition of the RAAS has been shown in animal models of diastolic dysfunction and in clinical trials to reduce these deleterious processes and to improve diastolic function. Despite these data, clinical trials performed with RAAS inhibitors in patients with HF‐PEF have failed to demonstrate morbidity and mortality benefits. To date, there is no proven effective therapy specifically for HF‐PEF. The deleterious effects of hypertension on mechanisms underlying the development of HF‐PEF underscore the importance of effective and early control of hypertension for the prevention of HF‐PEF.
Variability—The Drama of the Circulation
Authors: Rubin Mario F. , Brunelli Stephen M. , Townsend Raymond R.
Published: January 2010

J Clin Hypertens (Greenwich).

The two most common vital signs, ie, pulse and blood pressure (BP), are obtained to seek guidance in clinical management of patients in virtually all primary care practices. Even a cursory glance at their values, whether it is within a person over time or between patients on a particular day, reflects an amazing degree of variability. In this brief editorial we provide a focused review of the assessment and the importance of variability in within‐patient heart rate and BP and conclude with a few thoughts about the discordance in significance attached to these ubiquitous clinical measures.
Linear Versus Branching Depictions of Evolutionary History: Implications for Diagram Design
Authors: Novick Laura R. , Shade Courtney K. , Catley Kefyn M.
Published: January 2010

This article reports the results of an experiment involving 108 college students with varying backgrounds in biology. Subjects answered questions about the evolutionary history of sets of hominid and equine taxa. Each set of taxa was presented in one of three diagrammatic formats: a noncladogenic diagram found in a contemporary biology textbook or a cladogram in either the ladder or tree format. As predicted, the textbook diagrams, which contained linear components, were more likely than the cladogram formats to yield explanations of speciation as an anagenic process, a common misconception among students. In contrast, the branching cladogram formats yielded more appropriate explanations concerning levels of ancestry than did the textbook diagrams. Although students with stronger backgrounds in biology did better than those with weaker biology backgrounds, they generally showed the same effects of diagrammatic format. Implications of these results for evolution education and for diagram design more generally are discussed.
The Role of Differential Diagnoses in Self‐Triage Decision‐Making
Authors: Hall Elizabeth C. , Cooper Andrew A. , Watter Scott , Humphreys Karin R.
Published: January 2010

Self‐triage, or the decision if and when to seek medical care is crucial, but also intrinsically difficult. The current study evaluates how the presence of competing diagnoses with differing severities influences participants' likelihood of seeking care. Participants were healthy undergraduate students from McMaster University. In a within‐subjects design, participants rated the urgency with which they would seek medical care for a series of hypothetical scenarios. Each scenario included symptoms and either a low‐severity diagnosis, a high‐severity diagnosis, or a differential diagnosis where both high‐ and low‐severity options were presented. Participants rated low‐severity diagnoses as less urgent than high‐severity diagnoses, as expected. Critically, when presented with both low‐ and high‐severity options, participants rated scenarios with an intermediate level of urgency. Further analyses showed that participants appeared to base their urgency judgments on the low‐severity diagnosis and then adjust their ratings upward when presented with a high‐severity alternative. The results demonstrate that even when one of the possible diagnoses presented would require immediate care if accurate, ratings of urgency were significantly decreased if another less serious alternative was also suggested, potentially leading to sub‐optimal decision‐making. Implications of this observed pattern of self‐triage decision‐making are discussed.
Bibliometric Analyses on the Emergence and Present Growth of Positive Psychology
Authors: Schui Gabriel , Krampen Günter
Published: January 2010

Bibliometric results on the emergence and recent developmental trends of publications on positive psychology are presented within an outline of its precursors (i.e. humanistic psychology) and its special features in reference to humanistic psychology, health psychology, and developmental psychology. Terminological confusions (e.g. positivism in differential psychology vs. in epistemology; positive psychology) in psychological databases are described and resolved in bibliometric analyses for the time period between 2000 and 2008. The present results include findings reporting the incidence of multiple authorships, authors’ national institutional affiliations, the semantic network of publications on positive psychology, selected citation rates, and methodological classifications of the literature on positive psychology. With reference to PsycINFO, analyses show that publications on positive psychology increased markedly. Yet in comparison to other psychological subdisciplines and areas, literature output remains rather low. However, results on publication types and media point at a broad‐range impact of positive psychology on various applied and basic psychological subdisciplines. Together with the solid empirical foundation of positive psychology's literature, this leads to a positive prognosis for the further development of positive psychology.
Population genetics and breeding system ofTupistra pingbianensis(Liliaceae), a naturally rare plant endemic to SW China
Authors: QIAO Qin , ZHANG Chang‐Qin , MILNE Richard Ian
Published: January 2010

Abstract The levels and partitioning of genetic diversity and inbreeding depression were investigated inTupistra pingbianensis, a narrow endemic of southeast Yunnan, China, characterized by a naturally fragmented distribution due to extreme specialization on a rare habitat type. Here genetic diversity and patterns of genetic variation within and among 11 populations were analyzed using amplified fragment length polymorphism markers with 97 individuals across its whole geographical range. High levels of genetic variation were revealed both at the species level (P99= 96.012%;Ht= 0.302) and at the population level (P99= 51.41%;Hs= 0.224). Strong genetic differentiation among populations was also detected (FST= 0.2961; θII= 0.281), which corresponded to results reported for typical animal‐pollinated, mixed selfing, and outcrossing plant species. This result was consistent with mating patterns detected by our pollination experiments. The indirect estimate of gene flow based on θIIwas low (Nm= 0.64). Special habitat and its life history traits might play an important role in shaping the genetic diversity and the genetic structure of this species. A pollination experiment also failed to detect significant inbreeding depression upon F1fruit set, seed weight, and germinate rate fitness‐traits. As a naturally rare species,T. pingbianensisis not seriously genetically impoverished and likely to have adapted to tolerating a high level of inbreeding early in its history, we propose this species need only periodic monitoring to ensure their continued persistence, but not intervention to remain viable.
Designing a Retail Store Environment for the Mature Market: A European Perspective
Authors: Ann Petermans , Koenraad Van Cleempoel
Published: January 2010

This article discusses elderly consumers’ physical and social needs and wants in the marketplace, and presents case studies of two European food retail stores, which were designed to meet these concerns. The authors review information on the elderly consumers’ segment and discuss literature on retail design and retail branding, and question how designers should be more aware of multiple modes of interpreting brands, given generational differences and the existence of various types of retail settings. Given that the physical and social aspects are considered key to improving the shopping experiences of elderly consumers, the authors also review literature that focuses on the importance of creating efficient, user–friendly, and aesthetically pleasing shopping environments, which pay particular attention to intangible social aspects. Older consumers’ consumption satisfaction does not come merely from consuming for gathering tangible possessions, but from consuming while seeking intangible experiences, such as feeling welcome in a retail store ( Kim et al., 2005 ; Sherman, Schiffman, & Mathur, 2001 ). The authors contend that retail stores, properly designed to meet the needs and wants of the mature market, can strongly enhance this consumer segment's shopping experiences.

The article concludes with the presentation of two case studies of “senior supermarkets” in Europe. By investigating how these stores pay attention to physical and social aspects, which older consumers value as important, the authors analyze to what extent both stores are truly retail environments, adapted to the needs and wants of the mature market.
In situ observation of change in surface atomic arrangement of Sc–O∕W(100) system during phase transition at high temperature
Authors: Nagatomi T. , Nakanishi Y. , Takai Y.
Published: January 2010

In situ observation of low-energy electron diffraction (LEED) patterns during the phase transition of the Sc–O∕W(100) surface at high temperature was performed to investigate the correlation between the surface atomic arrangement, coverage of surface atoms, and work function during the phase transition. For this purpose, a LEED system enabling LEED observation at high temperatures of 1500–1900K was developed. The temperature dependence of the intensity of diffraction spots was measured, and the Debye temperatures were estimated for relevant surfaces. The changes in the intensity of diffraction spots during the phase transition were found to correlate with the changes in the coverage of surface atoms and work function. The present results revealed that surface phenomena such as surface segregation, oxidation, oxygen desorption, and diffusion of ScO complexes predominate the surface properties of the Sc–O∕W(100) system.
Attenuation of Rabies Virulence: Takeover by the Cytoplasmic Domain of Its Envelope Protein
Authors: Préhaud Christophe , Wolff Nicolas , Terrien Elouan , Lafage Mireille , Mégret Françoise , Babault Nicolas , Cordier Florence , Tan Gene S. , Maitrepierre Elodie , Ménager Pauline , Chopy Damien , Hoos Sylviane , England Patrick , Delepierre Muriel , Schnell Matthias J. , Buc Henri , Lafon Monique
Published: January 2010

Survival of rabies virus–infected neurons depends on a single amino acid in the PDZ-binding site of a viral protein.
Distinct Signal Codes Generate Dendritic Cell Functional Plasticity
Authors: Arima Kazuhiko , Watanabe Norihiko , Hanabuchi Shino , Chang Mikyoung , Sun Shao-Cong , Liu Yong-Jun
Published: January 2010

The cytokine TSLP triggers distinct signals in dendritic cells that program a T helper 2 (T
H
2)–type response.
Interleukin-1 (IL-1) Pathway
Authors: Weber Axel , Wasiliew Peter , Kracht Michael
Published: January 2010

IL-1α and IL-1β orchestrate the proinflammatory response by multiple tightly controlled mechanisms.
Interleukin-1β (IL-1β) Processing Pathway
Authors: Weber Axel , Wasiliew Peter , Kracht Michael
Published: January 2010

The NALP3 inflammasome pathway controls processing and release of interleukin-1β.
Secretly Signaling
Authors: Adler Elizabeth M.
Published: January 2010

CXCR7 mediates ligand-induced β-arrestin signaling in the absence of G protein signaling.
Optimum Swimming Speeds in Fish: The Problem of Currents
Authors: Trump Clifford L. , Leggett William C.
Published: January 2010

A model is presented describing the energetic consequences of various behavioral responses to currents. To minimize the energy cost of migration, when confronted with currents, fish must optimize both the mean swimming speed and the degree to which swimming speed is altered in response to changes in current velocity. The optimum swimming speed in a current is U0 + 1/b where U0 = mean current speed and b is a constant in the equation E(t) = a ebW(t) describing the relationship between specific energy expenditure per unit time E(t) and swimming speed W(t). In a variable current, such as might occur in estuaries and coastal areas, energy expenditure is minimized when these variations are ignored and a constant speed through the water is maintained. This is true even in conditions where occasional retrograde motion over the bottom may occur. The added energy costs of swimming at mean speeds ≠ U0 + 1/b or of varying swimming speeds in response to changes in current velocity are rigorously defined. Predictions of the model are in general agreement with empirical data on fish swimming behavior.Key words: swimming speeds, currents, fish, theoretical ecology, mathematical models, energetics, migration, behavior
Man-Made Changes in the Freshwater Input Rates of Hudson and James Bays
Authors: Prinsenberg S. J.
Published: January 2010

The freshwater input rates of the Hudson/James Bay region were obtained on a monthly time scale and include contributions of evaporation, precipitation, and river runoff. The yearly mean precipitation minus evaporation rate shows that it behaves as an oceanic region supplying the overlying air mass with moisture. The monthly runoff rates for the total region and James Bay alone have minimum values during the winter and maximum values during the spring freshet. The total freshwater input can be divided into a winter and summer season. The large input of the summer represents an average monthly addition of a 10.0-cm layer of fresh water while the smaller winter input amounts to addition of a 0.5-cm layer of freshwater. Annually, the total surface area receives a layer of 64 cm of freshwater.During the 1980s, four hydroelectric developments will cause temporal changes in the freshwater input cycle as winter river runoff rates will increase to values comparable to spring peak runoffs. In the Nelson–Churchill River development, the Churchill River runoff will be reduced to 29% of its natural state during the winter and to 54% during the summer. This water will increase the runoff into the Nelson River Delta by 52% in the winter and 10% in the summer. Similarly, the Eastmain River runoff will be reduced by 79%. The La Grande River will double its yearly averaged runoff rate and experience a 500% increase in runoff during the winter. The other two developments, Nottaway–Broadback–Rupert rivers (N.B.R.) and Great Whale–Little Whale proposals, will experience similar changes: large increases in the winter runoff rates and small decreases in summer rates.The total freshwater input into James Bay will be doubled during the winter months. In addition, half the future input will occur in the northern region which now receives only 20%. The La Grande River winter runoff rate will equal in magnitude that of the Nelson River Delta which presently accounts for 25% of the Hudson/James Bay winter runoff. The runoff for the total Hudson/James Bay region will also experience the largest changes during the winter when the average monthly runoff rate will increase by 52%, due largely to the La Grande Complex. On the other hand, the summer runoff rate for the total region will decrease by 6%.Key words: runoff, hydroelectric developments, Hudson Bay, James Bay, evaporation, precipitation, runoff alterations
Experimental Manipulation of Algal Bloom Composition by Nitrogen Addition
Authors: Barica J. , Kling H. , Gibson J.
Published: January 2010

Nitrogen (as ammonium, nitrate, or both) was added over an 8- to 12-wk period to enclosures in a small prairie lake and to a whole pond. In previous years, both had experienced seasonal anoxia as a result of collapses of Aphanizomenon flos-aquae blooms followed by a massive fish kill. Additions altered the bloom magnitude and the species composition if N was added prior to the appearance of A. flos-aquae. Low additions (~ 0.75–1.5 g m−8∙wk−1) initiated after the appearance of the cyanophyte bloom resulted in a significant reduction of the A. flos-aquae biomass, while the same addition at the time of a chlorophyte bloom (Scenedesmus and Oocystis sp.) caused a substantial shift to Microcystis aeruginosa. High additions (~ 7–14 g m−3∙wk−1) resulted in a total absence of cyanophytes and were followed by a complete shift to small chlorophytes and cryptomonads, with a total absence of A. flos-aquae and the fish kill. Low additions of N did not show any accumulation over 3–5 mo after discontinuation of the fertilization; high additions showed a significant accumulation of nitrate in the water. Both lake and pond returned to heavy A. flos-aquae blooms and fish kills the following summer when not fertilized.Key words: nutrient enrichment, nitrogen, algal blooms, fish kills, oxygen depletion, prairie lakes, biomanipulation, eutrophication
CALCULATION OF LINEAR AND NONLINEAR SCHRÖDINGER EQUATIONS BY THE EQUIVALENT NETWORK APPROACH AND ENVELOPE TECHNIQUE
Authors: KOUZAEV GUENNADI A.
Published: January 2010

In this letter, a technique is introduced which allows calculations of linear and nonlinear Schrödinger equations by commercially available circuit simulators. The results derived using the Circuit Envelope Simulation tool in Agilent Advanced Design System TM are tested by analytical calculations, and good correspondence is demonstrated.
RESOLUTION OF THE UNITY OF NORMALLY ORDERED GAUSSIAN OPERATOR FORM FOR CONSTRUCTING NEW QUANTUM MECHANICAL REPRESENTATIONS
Authors: MA SHAN-JUN
Published: January 2010

A convenient approach for deriving new quantum mechanical representations is presented, that is, constructing the unity of normally ordered Gaussian operator forms and then decomposing it as projection operators. As examples, two two-mode complicated entangled state representations are derived by combining the coordinate eigenvector completeness and the coherent state.
CALCULATION OF THE MOLAR VOLUME IN THE SOLID AND LIQUID PHASES OF CCl4
Authors: YURTSEVEN H. , KAVRUK D.
Published: January 2010

The molar volume of carbon tetrachloride is calculated as functions of temperature and pressure close to the melting point. By analyzing the experimental data for the pressure dependence of the thermal expansivity according to a power-law formula, the molar volume is calculated for the solid and liquid phases of this molecular organic compound.

Our calculations show that the molar volume of the solid phase increases almost linearly as the temperature and pressure increase, so that there is no anomalous behavior close to the melting point in CCl 4. In the liquid phase, it does not vary considerably within the given pressure and temperature ranges. Our calculated molar volumes can be compared with measurements for CCl 4 under the given pressure and temperature variations.
REDUCING FOUR-LEVEL TWO-MODE HAMILTONIAN TO AN EFFECTIVE TWO-LEVEL HAMILTONIAN WITH THE ADDITION OF KERR-LIKE MEDIUM
Authors: EL-DEBERKY M. A. A. , ALI M. F. M.
Published: January 2010

We consider a two-mode quantized field described in a coherent state interacting with a four-level atom. An effective Hamiltonian is obtained by adiabatically eliminating the intermediate two levels in a cascade process. The influence of the Stark shifts and the Kerr-like medium on the atomic inversion are examined, as well as on the field entropy, atomic purity and Mandel's Q-parameter. The results of the calculations are illustrated numerically.
GENERAL DIFFUSE-INTERFACE THEORIES AND AN APPROACH TO PREDICTIVE TUMOR GROWTH MODELING
Authors: ODEN J. TINSLEY , HAWKINS ANDREA , PRUDHOMME SERGE
Published: January 2010

While a large and growing literature exists on mathematical and computational models of tumor growth, to date tumor growth models are largely qualitative in nature, and fall far short of being able to provide predictive results important in life-and-death decisions. This is largely due to the enormous complexity of evolving biological and chemical processes in living tissue and the complex interactions of many cellular and vascular constituents in living organisms. Several new technologies have emerged, however, which could lead to significant progress in this important area: (i) the development of so-called phase-field, or diffuse-interface models, which can be developed using continuum mixture theory, and which provide a general framework for modeling the action of multiple interacting constituents. These are based on generalizations of the Cahn–Hilliard models for spinodal decomposition, and have been used recently in certain tumor growth theories; (ii) the emergence of predictive computational methods based on the use of statistical methods for calibration, model validation, and uncertainty quantification; (iii) advances in imaging, experimental cell biology, and other medical observational methodologies; and (iv) the advent of petascale computing that makes possible the resolution of features at scales and at speeds that were unattainable only a short time in the past.

Here we develop a general phenomenological thermomechanical theory of mixtures that employs phase-field or diffuse interface models of surface energies and reactions and which provides a framework for generalizing existing theories of the types that are in use in tumor growth modeling. In principle, the framework provides for the effects of M solid constituents, which may undergo large deformations, and for the effect of N - M fluid constituents, which could include highly nonlinear, non-Newtonian fluids. We then describe several special cases which have the potential of providing acceptable models of tumor growth. We then describe the beginning steps of the development of Bayesian methods for statistical calibration, model validation, and uncertainty quantification, which, with further work, could produce a truly predictive tool for studying tumor growth. In particular, we outline the processes of statistical calibration and validation that can be employed to determine if tumor growth models, drawn from the broad class of models developed here, are valid for prediction of key quantities of interest critical to making decisions on various medical protocols. We also describe how uncertainties in such key quantities of interest can be quantified in ways that can be used to establish confidence in predicted outcomes.
OPTIMAL RADIOTHERAPY TREATMENT PLANNING GOVERNED BY KINETIC EQUATIONS
Authors: FRANK MARTIN , HERTY MICHAEL , SANDJO ALBERT N.
Published: January 2010

In this paper we study a problem in radiotherapy treatment planning. This problem is formulated as an optimization problem of a functional of the radiative flux. It is constrained by the condition that the radiative flux, which depends on position, energy and direction of the particles, is governed by a Boltzmann integro-differential equation. We show the existence, uniqueness and regularity of solutions to this constrained optimization problem in an appropriate function space. The main new difficulty is the treatment of the energy loss term. Furthermore, we characterize optimal controls by deriving first-order optimality conditions.
ASYMPTOTIC BEHAVIOR OF MULTIDIMENSIONAL SCALAR RELAXATION SHOCKS
Authors: KWON BONGSUK , ZUMBRUN KEVIN
Published: January 2010

We establish pointwise bounds for the Green function and consequent linearized stability for multidimensional planar relaxation shocks of general relaxation systems whose equilibrium model is scalar, under the necessary assumption of spectral stability. Moreover, we obtain nonlinear L2asymptotic behavior/sharp decay rate of perturbed weak shocks of general simultaneously-symmetrizable relaxation systems, under small L1∩ H[d/2]+3perturbations with first moment in the normal direction to the front.
THE RIEMANN PROBLEM FOR MULTIPHASE FLOWS IN POROUS MEDIA WITH MASS TRANSFER BETWEEN PHASES
Authors: LAMBERT WANDERSON , MARCHESIN DAN
Published: January 2010

We are interested in solving systems of conservation laws modeling multiphase fluid flows under the approximation of local thermodynamical equilibrium except at very localized places. This equilibrium occurs for states on sheets of a stratified variety called the "thermodynamical equilibrium variety," obtained from thermodynamical laws. Strong deviation from equilibrium occurs in shocks connecting adjacent sheets of this variety.

We assume that fluids may expand and we model the physical problem by a system of equations where a velocity variable appears only in the flux terms, giving rise to a wave with "infinite" characteristic speed. We develop a general theory for fundamental solutions for this class of equations. We study all bifurcation loci, such as coincidence and inflection loci and develop a systematic approach to solve problems described by similar equations.

For concreteness, we exhibit the bifurcation theory for a representative system with three equations. We find the complete solution of the Riemann problem for two-phase thermal flow in porous media with two chemical species; to simplify the physics, the liquid phase consists of a single chemical species. We give an example of steam and nitrogen injection into a porous medium, with applications to geothermal energy recovery.
REGULARITY OF SOLUTIONS TO CHARACTERISTIC INITIAL-BOUNDARY VALUE PROBLEMS FOR SYMMETRIZABLE SYSTEMS
Authors: MORANDO ALESSANDRO , SECCHI PAOLO , TREBESCHI PAOLA
Published: January 2010

We consider the initial-boundary value problem for linear Friedrichs symmetrizable systems with characteristic boundary of constant rank. We assume the existence of the strong L2 solution satisfying a suitable energy estimate, but we do not assume any structural assumption sufficient for existence, such as the fact that the boundary conditions are maximally dissipative or the Kreiss–Lopatinski condition. We show that this is enough in order to get the regularity of solutions, in the natural framework of weighted anisotropic Sobolev spaces, provided the data are sufficiently smooth.
ScaLAPACK's MRRR algorithm
Authors: Vömel Christof
Published: January 2010

The (sequential) algorithm of Multiple Relatively Robust Representations, MRRR, is a more efficient variant of inverse iteration that does not require reorthogonalization. It solves the eigenproblem of an unreduced symmetric tridiagonal matrix
T
∈

R
n × n

at
O
(
n
2
) cost. The computed normalized eigenvectors are numerically orthogonal in the sense that the dot product between different vectors is
O
(
n
ϵ), where ϵ refers to the relative machine precision.

This article describes the design of ScaLAPACK's parallel MRRR algorithm. One emphasis is on the critical role of the representation tree in achieving both adequate accuracy and parallel scalability. A second point concerns the favorable properties of this code: subset computation, the use of static memory, and scalability.

Unlike ScaLAPACK's Divide & Conquer and QR, MRRR can compute subsets of eigenpairs at reduced cost. And in contrast to inverse iterations which can fail, it is guaranteed to produce a satisfactory answer while maintaining memory scalability.

ParEig, the parallel MRRR algorithm for PLAPACK, uses dynamic memory allocation. This is avoided by our code at marginal additional cost. We also use a different representation tree criterion that allows for more accurate computation of the eigenvectors but can make parallelization more difficult.
Singularity-free evaluation of collapsed-coordinate orthogonal polynomials
Authors: Kirby Robert C.
Published: January 2010

The
L
2
-orthogonal polynomials used in finite and spectral element methods on nonrectangular elements may be defined in terms of
collapsed
coordinates, wherein the shapes are mapped to a square or cube by means of a singular change of variables. The orthogonal basis is a product of specific Jacobi polynomials in these new coordinates. Implementations of these polynomials require special handling of the coordinate singularities. We derive new recurrence relations for these polynomials on triangles and tetrahedra that work directly in the original coordinates. These relations, also applicable to pyramids and prisms, do not require any special treatment of singular points. These recurrences are seen to speed up both symbolic and numerical computation of the orthogonal polynomials.
Algorithm 899
Authors: Sarra Scott A.
Published: January 2010

Global polynomial approximation methods applied to piecewise continuous functions exhibit the well-known Gibbs phenomenon. We summarize known methods to remove the Gibbs oscillations and present a collection of Matlab programs that implement the methods. The software features a Graphical User Interface that allows easy access to the postprocessing algorithms for benchmarking and educational purposes.
Deciding security properties for cryptographic protocols. application to key cycles
Authors: Comon-Lundh Hubert , Cortier Véronique , Zălinescu Eugen
Published: January 2010

There is a large amount of work dedicated to the formal verification of security protocols. In this article, we revisit and extend the NP-complete decision procedure for a bounded number of sessions. We use a, now standard, deducibility constraint formalism for modeling security protocols. Our first contribution is to give a simple set of constraint simplification rules, that allows to reduce any deducibility constraint to a set of
solved forms
, representing all solutions (within the bound on sessions).

As a consequence, we prove that deciding the existence of key cycles is NP-complete for a bounded number of sessions. The problem of key-cycles has been put forward by recent works relating computational and symbolic models. The so-called
soundness
of the symbolic model requires indeed that no key cycle (e.g., enc(k, k)) ever occurs in the execution of the protocol. Otherwise, stronger security assumptions (such as KDM-security) are required.

We show that our decision procedure can also be applied to prove again the decidability of authentication-like properties and the decidability of a significant fragment of protocols with timestamps.
Proof search specifications of bisimulation and modal logics for the π-calculus
Authors: Tiu Alwen , Miller Dale
Published: January 2010

We specify the operational semantics and bisimulation relations for the finite φ-calculus within a logic that contains the ∇ quantifier for encoding
generic judgments
and definitions for encoding fixed points. Since we restrict to the finite case, the ability of the logic to unfold fixed points allows this logic to be complete for both the inductive nature of operational semantics and the coinductive nature of bisimulation. The ∇ quantifier helps with the delicate issues surrounding the scope of variables within φ-calculus expressions and their executions (proofs). We illustrate several merits of the logical specifications permitted by this logic: they are natural and declarative; they contain no side-conditions concerning names of variables while maintaining a completely formal treatment of such variables; differences between late and open bisimulation relations arise from familar logic distinctions; the interplay between the three quantifiers (∀, ∃, and ∇) and their scopes can explain the differences between early and late bisimulation and between various modal operators based on bound input and output actions; and proof search involving the application of inference rules, unification, and backtracking can provide complete proof systems for one-step transitions, bisimulation, and satisfaction in modal logic. We also illustrate how one can encode the φ-calculus with replications, in an extended logic with induction and co-induction.
Compositional may-must program analysis
Authors: Godefroid Patrice , Nori Aditya V. , Rajamani Sriram K. , Tetali Sai Deep
Published: January 2010

Program analysis tools typically compute two types of information: (1)
may
information that is true of
all
program executions and is used to prove the absence of bugs in the program, and (2)
must
information that is true of
some
program executions and is used to prove the existence of bugs in the program. In this paper, we propose a new algorithm, dubbed SMASH, which computes both may and must information
compositionally
. At each procedure boundary, may and must information is represented and stored as may and must summaries, respectively. Those summaries are computed in a demand driven manner and possibly using summaries of the opposite type. We have implemented SMASH using predicate abstraction (as in SLAM) for the may part and using dynamic test generation (as in DART) for the must part. Results of experiments with 69 Microsoft Windows 7 device drivers show that SMASH can significantly outperform may-only, must-only and non-compositional may-must algorithms. Indeed, our empirical results indicate that most complex code fragments in large programs are actually often either easy to prove irrelevant to the specific property of interest using may analysis
or
easy to traverse using directed testing. The fine-grained coupling and
alternation
of may (universal) and must (existential) summaries allows SMASH to easily navigate through these code fragments while traditional may-only, must-only or non-compositional may-must algorithms are stuck in their specific analyses.
Automatic numeric abstractions for heap-manipulating programs
Authors: Magill Stephen , Tsai Ming-Hsien , Lee Peter , Tsay Yih-Kuen
Published: January 2010

We present a logic for relating heap-manipulating programs to numeric abstractions. These numeric abstractions are expressed as simple imperative programs over integer variables and have the property that termination and safety of the numeric program ensures termination and safety of the original, heap-manipulating program. We have implemented an automated version of this abstraction process and present experimental results for programs involving a variety of data structures.
From program verification to program synthesis
Authors: Srivastava Saurabh , Gulwani Sumit , Foster Jeffrey S.
Published: January 2010

This paper describes a novel technique for the synthesis of imperative programs. Automated program synthesis has the potential to make programming and the design of systems easier by allowing programs to be specified at a higher-level than executable code. In our approach, which we call proof-theoretic synthesis, the user provides an input-output functional specification, a description of the atomic operations in the programming language, and a specification of the synthesized program's looping structure, allowed stack space, and bound on usage of certain operations. Our technique synthesizes a program, if there exists one, that meets the input-output specification and uses only the given resources.

The insight behind our approach is to interpret program synthesis as generalized program verification, which allows us to bring verification tools and techniques to program synthesis. Our synthesis algorithm works by creating a program with unknown statements, guards, inductive invariants, and ranking functions. It then generates constraints that relate the unknowns and enforces three kinds of requirements: partial correctness, loop termination, and well-formedness conditions on program guards. We formalize the requirements that program verification tools must meet to solve these constraint and use tools from prior work as our synthesizers.

We demonstrate the feasibility of the proposed approach by synthesizing programs in three different domains: arithmetic, sorting, and dynamic programming. Using verification tools that we previously built in the VS3 project we are able to synthesize programs for complicated arithmetic algorithms including Strassen's matrix multiplication and Bresenham's line drawing; several sorting algorithms; and several dynamic programming algorithms. For these programs, the median time for synthesis is 14 seconds, and the ratio of synthesis to verification time ranges between 1x to 92x (with an median of 7x), illustrating the potential of the approach.
Integrating typed and untyped code in a scripting language
Authors: Wrigstad Tobias , Nardelli Francesco Zappa , Lebresne Sylvain , Östlund Johan , Vitek Jan
Published: January 2010

Many large software systems originate from untyped scripting language code. While good for initial development, the lack of static type annotations can impact code-quality and performance in the long run. We present an approach for integrating untyped code and typed code in the same system to allow an initial prototype to smoothly evolve into an efficient and robust program. We introduce
like types
, a novel intermediate point between dynamic and static typing. Occurrences of like types variables are checked statically within their scope but, as they may be bound to dynamic values, their usage is checked dynamically. Thus like types provide some of the benefits of static typing without decreasing the expressiveness of the language. We provide a formal account of like types in a core object calculus and evaluate their applicability in the context of a new scripting language.
Paralocks
Authors: Broberg Niklas , Sands David
Published: January 2010

This paper presents Paralocks, a language for building expressive but statically verifiable fine-grained information flow policies. Paralocks combine the expressive power of Flow Locks (Broberg & Sands, ESOP'06) with the ability to express policies involving run-time principles, roles (in the style of role-based access control), and relations (such as "acts-for" in discretionary access control). We illustrate the Paralocks policy language by giving a simple encoding of Myers and Liskov's Decentralized Label Model (DLM). Furthermore - and unlike the DLM - we provide an information flow semantics for full Paralock policies. Lastly we illustrate how Paralocks can be statically verified by providing a simple programming language incorporating Paralock policy specifications, and a static type system which soundly enforces information flow security according to the Paralock semantics.
The Fox Genes in the Liver: From Organogenesis to Functional Integration
Authors: Le lay John , Kaestner Klaus H.
Published: January 2010

Formation and function of the liver are highly controlled, essential processes. Multiple signaling pathways and transcriptional regulatory networks cooperate in this complex system. The evolutionarily conserved FOX, for Forkhead bOX, class of transcriptional regulators is critical to many aspects of liver development and function. The FOX proteins are small, mostly monomeric DNA binding factors containing the so-called winged helix DNA binding motif that distinguishes them from other classes of transcription factors. We discuss the biochemical and genetic roles of Foxa, Foxl1, Foxm1, and Foxo, as these have been shown to regulate many processes throughout the life of the organ, controlling both formation and function of the liver.
Multiantenna Analog Network Coding for Multihop Wireless Networks
Authors: Annavajjala Ramesh , Maaref Amine , Zhang Jinyun
Published: January 2010

This paper proposes a two-phase minimum mean-square-error bidirectional amplify-and forward (MMSE-BAF) relaying protocol to allow two sources exchange independent messages via a relay node equipped with multiple antennas. MMSE-BAF performs a joint linear MMSE filtering of the received signal after the multiple access phase before amplifying and forwarding the filtered signal using a single transmit antenna, possibly through a specific antenna selection procedure, during the broadcast phase. The proposed protocol extends upon the so-called analog network coding schemes in the literature in that it inherently exploits the multiple antennas at the relay station to reduce the noise enhancement typical of an AF protocol, and can also compensate for link imbalances between the relay and the sources and is agnostic to sources' modulation and coding schemes. We derive the instantaneous signal-to-noise ratio expressions for the received signal by the sources in the downlink and provide extensive link-level simulations for the MMSE-BAF protocol subject to both frequency flat and selective fading. Furthermore, we pinpoint the modifications to be incorporated into the IEEE 802.16e orthogonal-frequency-division multiple access (OFDMA) cellular standard (mobile WiMax) to enable support of multiantenna bidirectional communications and show that MMSE-BAF is a viable solution within that framework.
The Receptor for Advanced Glycation End Products (RAGE) and the Lung
Authors: Buckley Stephen T. , Ehrhardt Carsten
Published: January 2010

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily of cell surface molecules. As a pattern-recognition receptor capable of binding a diverse range of ligands, it is typically expressed at low levels under normal physiological conditions in the majority of tissues. In contrast, the lung exhibits high basal level expression of RAGE localised primarily in alveolar type I (ATI) cells, suggesting a potentially important role for the receptor in maintaining lung homeostasis. Indeed, disruption of RAGE levels has been implicated in the pathogenesis of a variety of pulmonary disorders including cancer and fibrosis. Furthermore, its soluble isoforms, sRAGE, which act as decoy receptors, have been shown to be a useful marker of ATI cell injury. Whilst RAGE undoubtedly plays an important role in the biology of the lung, it remains unclear as to the exact nature of this contribution under both physiological and pathological conditions.
A Low-Power Digitally Controlled Oscillator for All Digital Phase-Locked Loops
Authors: Zhao Jun , Kim Yong-Bin
Published: January 2010

A low-power and low-jitter 12-bit CMOS digitally controlled oscillator (DCO) design is presented. The Low-Power CMOS DCO is designed based on the ring oscillator implemented with Schmitt trigger inverters. The proposed DCO circuit uses control codes of thermometer type to reduce jitters. Performance of the DCO is verified through a novel All Digital Phase-Locked Loop (ADPLL) designed with a unique lock-in process by employing a time-to-digital converter, where both the frequency of the reference clock and the delay between DCO_output and DCO_clock is measured. A carefully designed reset process reduces the phase acquisition process to two cycles. The ADPLL was implemented using the 32 nm Predictive Technology Model (PTM) at 0.9 V supply voltage, and the simulation results show that the proposed ADPLL achieves 10 and 2 reference cycles of frequency and phase acquisitions, respectively, at 700 MHz with less than 67 ps peak-to-peak jitter. The DCO consumes 2.2 mW at 650 MHz with 0.9 V power supply.
Clinical Safety and Efficacy of a Novel Thermoreversible Polyhexanide-Preserved Wound Covering Gel
Authors: Goertz O. , Abels C. , Knie U. , May T. , Hirsch T. , Daigeler A. , Steinau H.-U. , Langer S.
Published: January 2010

Background: An ideal topical formulation for wound therapy does not exist. The aim of this study was to develop a novel improved therapeutic option for the treatment of acute and chronic wounds. Methods: A transparent wound gel which is in a liquid state below and in a gel state at or above room temperature was developed. Forty-four patients were included in this open randomized controlled single-center study. Flammazine™ served as control in the treatment of skin graft donor sites. Wounds were assessed for time of dressing change and overall satisfaction of patients and health care providers. The data were analyzed using the nonparametric Mann-Whitney test. Results: The wound gel proved to be superior in comparison with Flammazine with respect to wound assessment (p = 0.002), staining (p = 0.007), leaking (p = 0.032) and smell (p = 0.034). Flammazine showed favorable results regarding the parameters dehydration of the dressings (p = 0.012) and wound adherence (p = 0.005). The evaluation of the overall dressing change process showed no significant differences. Conclusion: The thermoreversible wound gel containing polyhexanide allows for good handling and wound assessment. This study demonstrated a high satisfaction level of patient and health care providers, and the wound gel proved an effective alternative to commonly used treatments.
Endothelial-Regenerating Cells
Authors: Steinmetz Martin , Nickenig Georg , Werner Nikos
Published: January 2010

Atherosclerosis is the most common cause for cardiovascular diseases and is based on endothelial dysfunction. A growing body of evidence suggests the contribution of bone marrow–derived endothelial progenitor cells, monocytic cells, and mature endothelial cells to vessel formation and endothelial rejuvenation. To this day, various subsets of these endothelial-regenerating cells have been identified according to cellular origin, phenotype, and properties in vivo and in vitro. However, the definition and biology, especially of endothelial progenitor cells, is complex and under heavy debate. In this review, we focus on current definitions of endothelial progenitor cells, highlight the clinical relevance of endothelial-regenerating cells, and provide new insights into cell-cell interactions involved in endothelial cell rejuvenation.
Arterial Stiffness Is Regulated by Nitric Oxide and Endothelium-Derived Hyperpolarizing Factor During Changes in Blood Flow in Humans
Authors: Bellien Jeremy , Favre Julie , Iacob Michele , Gao Ji , Thuillez Christian , Richard Vincent , Joannidès Robinson
Published: January 2010

Cytochrome-derived epoxyeicosatrienoic acids may be important endothelium-derived hyperpolarizing factors, opening calcium-activated potassium channels, but their involvement in the regulation of arterial stiffness during changes in blood flow in humans is unknown. In healthy volunteers, we measured arterial pressure, radial artery diameter, wall thickness, and flow (NIUS02) during hand skin heating in the presence of saline or inhibitors of NO synthase (
N
G
-monomethyl-
l
-arginine), calcium-activated potassium channels (tetraethylammonium), and cytochrome epoxygenases (fluconazole). Arterial compliance and elastic modulus were calculated and fitted as functions of midwall stress to suppress the confounding influence of geometric changes. Under saline infusion, heating induced an upward shift of the compliance-midwall stress curve and a downward shift of the modulus-midwall stress curve demonstrating a decrease in arterial tone and stiffness when blood flow increases. These shifts were reduced by
N
G
-monomethyl-
l
-arginine and abolished by the combinations of
N
G
-monomethyl-
l
-arginine+tetraethylammonium and
N
G
-monomethyl arginine+fluconazole. In parallel, in isolated mice coronary arteries, fluconazole and tetraethylammonium reduced the relaxations to acetylcholine. However, fluconazole did not affect the relaxations to the openers of calcium-activated potassium channels of small- and intermediate-conductance NS309 and of large-conductance NS1619 excluding a direct effect on these channels. Moreover, tetraethylammonium reduced the relaxations to NS1619 but not to NS309, suggesting that the endothelium-derived hyperpolarizing factor involved mainly acts on large-conductance calcium-activated potassium channels. These results show in humans that, during flow variations, arterial stiffness is regulated by the endothelium through the release of both NO and cytochrome-related endothelium-derived hyperpolarizing factor.