bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring causal pathways in demographic parameter variation: path analysis of mark–recapture data
Authors: Gimenez Olivier , Anker‐Nilssen Tycho , Grosbois Vladimir
Published: September 2011

1. Inference about demographic parameters of animal and plant natural populations is important to evaluate the consequences of global changes on populations. Investigating the factors driving their variation over space and time allows evaluating the relative importance of biotic and abiotic variables in shaping the dynamics of a population. Although numerous studies have identified the factors possibly affecting population dynamics, they have barely formally determined the routes by which these different factors are related to demographic parameters.

2. We focus on mark–recapture (MR) models that provide unbiased estimators of demographic parameters, while explicitly coping with imperfect detection inherent to wild populations. MR models allow estimating the effect of covariates on demographic parameters and testing their significance in a regression‐like framework. However, these models can only detect correlations and do not inform on causal pathways (e.g. direct vs. indirect effects) in the relationships between demographic parameters and the factors possibly explaining their variability.

3. We develop an integrated model to perform path analysis (PA) of MR data, to examine causal relationships among several (including demographic) variables. This approach is implemented in a Bayesian framework using Markov chain Monte Carlo.

4. To motivate our developments, we analyse 17 years of mark–recapture data from Atlantic puffins (Fratercula arctica), to investigate the mechanisms through which environmental conditions have an impact on puffins’ adult survival. Using our PA‐based MR modelling approach, we found that local climatic conditions had an indirect and lagged impact on puffin survival through their influence on local abundance of herring. Besides, we found no evidence for any lagged effect through an alternative unknown pathway (e.g. abundance of another resource).

5. Our method allows elucidating pathways through which environmental, trophic or density‐dependent factors influence demographic parameters, while accounting for detectability <1. This is a critical step to understand the interactions of a species with its environment and to predict the impacts of global change on its viability.
Accounting for Roller Dynamics in the Design of Bifilar Torsional Vibration Absorbers
Authors: Monroe Ryan J. , Shaw Steven W. , Haddow Alan H. , Geist Bruce K.
Published: September 2011

Centrifugal pendulum vibration absorbers are used for reducing engine-order torsional vibrations in rotating machines. The most common configuration of these devices utilizes a bifilar suspension in which the absorber mass is suspended by a pair of cylindrical rollers that allow it to move along a prescribed path that is determined by the shape of machined cutouts on the rotor and the absorber mass. Previous studies have considered how to account for the roller inertia in selecting the linear (small amplitude) tuning characteristics of the absorber system. Here, we describe a systematic study of the nonlinear (finite amplitude) aspects of this system and show that there exists an absorber path for which the absorber/roller system maintains the same frequency of free oscillation over all physically possible amplitudes when the rotor spins at a constant rate. This tautochronic path has been well known for the case with zero roller inertia, and herein, for the first time, the corresponding path with rollers is shown to exist, and a method for its construction is presented. In addition, we carry out a perturbation analysis of the steady-state dynamic response of the rotor/absorber/roller system in order to quantify the effects of various approximations commonly used with regard to the roller dynamics. The results show that if one accounts for the rollers in the linear absorber tuning, the nonlinear system response is essentially insensitive to the selection of the nonlinear tuning parameter, so long as it is close to the tautochronic value.
Flow Regime Identification Under Adiabatic Upward Two-Phase Flow in a Vertical Rod Bundle Geometry
Authors: Paranjape Sidharth , Chen Shao-Wen , Hibiki Takashi , Ishii Mamoru
Published: September 2011

Flow regime maps were obtained for adiabatic air-water two-phase flow through a flow channel with 8 × 8 rod bundle, which simulated a typical rod bundle in a boiling water reactor. Impedance void meters were used to measure the area averaged void fraction at various axial locations in the flow channel. The Cumulative Probability Distribution Functions of the signals from the impedance meters were utilized along with self organizing neural network methodology to identify the flow regimes. The flow regimes were identified at five axial locations in the channel in order to understand the development of the flow regimes in axial direction. The experimental flow regime transition boundaries for bubbly to cap-bubbly and part of the cap-turbulent to churn-turbulent agreed with the theoretical boundaries of bubbly to slug and slug to churn-turbulent in round pipes. In addition, the two impedance void meters located across a spacer grid, revealed the nature of change in the flow regime across the spacer grid.
Experimental Investigation of the Use of Synthetic Jets for Mixing in Vessels
Authors: Al-Atabi Mushtak
Published: September 2011

Mixing is an important process in various industries. Different designs have been suggested in order to reduce the local shear rates in mechanically stirred mixing vessels, also known as continuously stirred tank reactors, in order to account for the mixing requirements for sensitive materials such as biological materials and biofluids where the high shear rate may damage the sensitive materials. This paper reports on the development of a continuously stirred tank reactor that can be used to achieve a variety of mixing assignments. This mixing is achieved using synthetic jets. The mixing performance was assessed using flow visualization techniques. The effects of fluid viscosity on mixing time were investigated. The results are very encouraging and are suggestive that the use of synthetic jets in mixing is a viable alternative to the conventional methods of mixing in vessels.
Fabrication and performance of graphene nanoelectromechanical systems
Authors: Barton Robert A. , Parpia Jeevak , Craighead Harold G.
Published: September 2011

As a result of the recent progress in fabricating large-area graphene sheets, graphene-based mechanical devices have become vastly easier to manufacture and now show even greater promise for a range of applications. This article reviews the progress of resonant graphene nanoelectromechanical systems and the possible applications of this technology to signal processing, sensing, and other areas. After discussing recent advances in fabrication and measurement techniques that make graphene resonators a viable technology, the article presents what is known about the performance of graphene mechanical systems. The authors also highlight unresolved questions, such as the source of the dissipation in graphene resonators, and discuss the progress made on these issues to date. The authors conclude with a discussion of important future directions for graphene research and the applications for which graphene nanomechanical devices may be well suited.
Flexible ZnSnO3/Ag/ZnSnO3 multilayer electrodes grown by roll-to-roll sputtering on flexible polyethersulfone substrates
Authors: Choi Yoon-Young , Kim Han-Ki , Koo Hyun-Woo , Kim Tae-Woong , Lee Sung-Nam
Published: September 2011

The authors report on the characteristics of flexible ZnSnO3 (ZTO)/Ag/ZTO multilayer electrodes sputtered on a flexible polyethersulfone substrate using roll-to-roll sputtering at room temperature. The sheet resistance and optical transmittance of the flexible ZTO/Ag/ZTO multilayer were mainly affected by the thickness and morphology of the Ag layer inserted between the ZTO layers. Dependence of photoluminescence peak intensity on the Ag thickness indicates that the high transmittance of the flexible ZTO/Ag/ZTO electrode can be explained by surface plasmon resonance as well as antireflection effects. At the optimized Ag thickness (10 nm), the flexible ZTO/Ag/ZTO exhibited a resistivity of 4.15 × 10−5 Ω-cm, an optical transmittance of 86.03%, and a figure of merit value of 42.83 × 10−3 Ω−1 comparable to those of conventional crystalline ITO electrodes. In addition, the optimized ZTO/Ag/ZTO sample showed constant resistance change (ΔR/R) during repeated bending cycles, indicating the robustness of the ZTO/Ag/ZTO electrode as a flexible electrode for cost efficient-flexible displays and photovoltaics.
Upper gastrointestinal cancer in its early stages is predominantly asymptomatic
Authors: Berrill James W , Turner Jeff K , Hurley Jo J , Swift Gillian , Dolwani Sunil , Green John T
Published: September 2011

Background

Current guidelines for urgent endoscopic investigation of dyspepsia are based on alarm features and age criteria. However, there is concern that this type of guideline may delay the diagnosis of upper gastrointestinal (GI) cancer.

Objective

To evaluate the timescale of symptoms in upper GI cancer, determining whether patients experience dyspepsia before developing alarm features, and hence whether the current guidelines may delay diagnosis.

Method

A prospective study of patients diagnosed with upper GI cancer between May 2004 and January 2007. A structured interview was performed directly after endoscopic diagnosis regarding the nature and duration of symptoms.

Results

Alarm features were present in 56 of the 60 patients interviewed. Only eight patients reported dyspepsia before developing their alarm feature; three of these had complained of dyspepsia for >10 years, one reported dyspepsia preceding the alarm feature by 18 months and in four patients dyspepsia preceded the alarm feature by ≤8 weeks. Preceding dyspepsia did not cause significant delay in referral for endoscopy (p=0.670), or affect tumour stage at diagnosis (p=0.436) or length of survival (p=0.325).

Conclusion

It is rare for patients with upper GI cancer to experience significant dyspepsia before the onset of their alarm symptoms, therefore limiting the prospect of an earlier diagnosis. Early upper GI cancer is largely asymptomatic, and guidelines should limit the availability of open-access gastroscopy in simple dyspepsia. Increased awareness of the need to urgently investigate patients with concurrent anaemia or weight loss is required.
STATISTICAL PROPERTIES OF THE ARITHMETIC CORRELATION OF SEQUENCES
Authors: GORESKY MARK , KLAPPER ANDREW
Published: September 2011

In this paper we study arithmetic correlations of sequences. Arithmetic correlations are the with-carry analogs of classical correlations. We analyze the arithmetic autocorrelations of non-binary ℓ-sequences, showing that they are nearly optimal. We analyze the expected auto- and cross-correlations of sequences with fixed shift, averaged over all sequences with a fixed period. We analyze the expected autocorrelations of a fixed sequence, averaged over all shifts.
NON-BOOLEAN ALMOST PERFECT NONLINEAR FUNCTIONS ON NON-ABELIAN GROUPS
Authors: POINSOT LAURENT , POTT ALEXANDER
Published: September 2011

The purpose of this paper is to present extended definitions and characterizations of the classical notions of APN and maximum nonlinear Boolean functions to deal with the case of mappings from a finite group K to another one N with the possibility that one or both groups are non-Abelian.
SOFT SUPERSYMMETRY BREAKING MASSES AND μ PARAMETER FROM DYNAMICAL REARRANGEMENT OF EXOTIC U(1) SYMMETRIES
Authors: KAWAMURA YOSHIHARU , MIURA TAKASHI
Published: September 2011

We propose a mechanism that the soft supersymmetry breaking masses and μ parameter can be induced from the dynamical rearrangement of local U(1) symmetries in a five-dimensional model. It offers to a solution to μ problem if there is a large hierarchy among the relevant U(1) charge of Higgsinos and that of hidden fields which stabilize the extra-dimensional component of U(1) gauge boson.
TWO-PHOTON DECAY OF Z′ AS A PROBE OF BOSE SYMMETRY VIOLATION AT THE CERN LHC
Authors: GNINENKO S. N. , YU. IGNATIEV A. , MATVEEV V. A.
Published: September 2011

The question if the Bose statistics is broken at the TeV scale is discussed. The decay of a new heavy spin-1 gauge boson Z′ into two photons, Z′ → γγ, is forbidden by the Bose statistics among other general principles of quantum field theory (Landau–Yang theorem). We point out that the search for this decay can be effectively used to probe the Bose symmetry violation at the CERN LHC.
SUPERGRAVITY DUAL OF THE SUPERCONFORMAL ANOMALY
Authors: CHEN WENFENG
Published: September 2011

The supergravity dual of the superconformal anomaly multiplet in a four-dimensional supersymmetric gauge theory is investigated. We consider a well-established dual correspondence between an [Formula: see text]SU(N+M) × SU(N) supersymmetric gauge theory and type IIB superstring in a space–time background described by the Klebanov–Strassler solution. Based on the fact that fractional D3-branes lead to superconformal anomaly on the field theory side and in the meantime deform AdS 5 × T1, 1 space–time background on the gravity side, we observe the five-dimensional gauged supergravity yielded from the spontaneous compactification on the deformed T1, 1, and find that the spontaneous breaking of local symmetries and the consequent super-Higgs effect in the gauged AdS5 supergravity should be the dual of the superconformal anomaly of the four-dimensional supersymmetric gauge theory.
CHAOS CAUSED BY HYSTERESIS AND SATURATION PHENOMENON IN 2-DOF VIBRATIONS OF THE ROTOR SUPPORTED BY THE MAGNETO-HYDRODYNAMIC BEARING
Authors: AWREJCEWICZ J. , DZYUBAK L. P.
Published: September 2011

2-DOF nonlinear dynamics of the rotor supported by the magneto-hydrodynamic bearing is investigated using the perturbation analysis. The two modes corresponding to the vertical and horizontal vibrations of the rotor are coupled. The nonresonant case and the various resonant cases (with and without an internal resonance) are considered. The frequency-response curves are obtained. When the amplitude of the external harmonic excitation is near to one of the natural frequency of the vibrations and the system experiences conditions of an internal resonance, a saturation phenomenon occurs. When the amplitude of the external excitation increases, after some critical value the energy pumping between various submotions of the rotor occurs for each mode. Further, it was shown, that in the case of rigid magnetic materials, hysteresis may be a cause of chaotic vibrations of the rotor. Chaotic regions and the amplitude level contours of the rotor vibrations have been obtained in various control parameter planes.
CHAOTIC VIBRATIONS OF TWO-LAYERED BEAMS AND PLATES WITH GEOMETRIC, PHYSICAL AND DESIGN NONLINEARITIES
Authors: AWREJCEWICZ J. , KRYSKO A. V. , BOCHKAREV V. V. , BABENKOVA T. V. , PAPKOVA I. V. , MROZOWSKI J.
Published: September 2011

In this paper, the theory of nonlinear interaction of two-layered beams and plates taking into account design, geometric and physical nonlinearities is developed. The theory is mainly developed relying on the first approximation of the Euler–Bernoulli hypothesis. Winkler type relation between clamping and contact pressure is applied allowing the contact pressure to be removed from the quantities being sought. Strongly nonlinear partial differential equations are solved using the finite difference method regarding space and time coordinates. On each time step the iteration procedure, which improves the contact area between the beams is applied and also the method of changeable stiffness parameters is used. A computational example regarding dynamic interaction of two beams depending on a gap between the beams is given. Each beam is subjected to transversal sign-changeable load, and the upper beam is hinged, whereas the bottom beam is clamped. It has been shown that for some fixed system parameters and with an increase of the external load amplitude, synchronization between two beams occurs with the upper beam vibration frequency. Qualitative analysis of the interaction of two noncoupled beams is also extended to the study of noncoupled plates. Charts of beam vibration types versus control parameters {q0, ωp}, i.e. the frequency and amplitude of excitation are constructed. Similar and previously described competitions have been reported in the case of two-layered plates.
VIBRATION OF CIRCULAR BLADED DISK WITH IMPERFECTIONS
Authors: PŮST LADISLAV , PEŠEK LUDĚK
Published: September 2011

The steady state response of a model of circular bladed disk with imperfection is investigated. Disk imperfection results from additional two groups of damping heads fixed on opposite ends of one diameter. These damping heads are introduced into the computing model as additional point mass, damping and stiffness. Such type of imperfection causes the bifurcation of double eigenfrequencies into pairs of close eigenfrequencies. The effect of imperfection is examined both numerically on three-dimensional nonrotating FE-model and analytically on a simplified split 2DOF model of rotating disk excited by single point harmonic force. Nonlinear friction connection is analyzed and equivalent linear damping coefficient is derived and used in the calculation procedure. It is shown that nonproportional distribution of damping strongly influences the high of resonance peaks. Some examples of response curves illustrate the dynamic properties of stationary and rotating disks with mass-damping-stiffness imperfection.
LIMITING PHASE TRAJECTORIES AND TRANSIENT RESONANCE OSCILLATIONS IN 1 AND 2 DOF ASYMMETRIC NONLINEAR SYSTEMS
Authors: MANEVITCH E. L. , MANEVITCH L. I.
Published: September 2011

The concept of limiting phase trajectories (LPT) has been introduced by one of the authors to describe intensive energy exchange between weakly coupled oscillators or oscillatory chains. It turns out that LPT can be considered as an alternative to nonlinear normal modes (NNMs), which are characterized by conservation of energy. LPT (in the introduced coordinates) describes the vibroimpact-type process with saw-tooth amplitude and a discontinuous derivative. It was shown earlier that this concept could also be extended to systems with one degree of freedom (DoF). In this case energy exchange between the oscillator and the source of energy can occur. In this paper, we generalize the above results in several ways, namely: (1) a consideration of the asymmetry of elastic potential; (2) a detailed description of the origin of vibroimpact-type behavior and the transition from nonresonant nonstationary oscillations to resonant ones (3) a direct application of obtained results to transient vibrations in strongly asymmetric 2DoF systems.
THE INFLUENCE OF FLEXIBILITY OF THE SUPPORT ON DYNAMIC BEHAVIOR OF A CRANE
Authors: URBAŚ ANDRZEJ , SZCZOTKA MAREK , WOJCIECH STANISŁAW
Published: September 2011

The problem of control of the motion of a crane is considered in the paper. The mathematical model of the system is formulated using joint coordinates and homogenous transformations. The dynamic optimization method is applied in order to find drive functions realizing the desired trajectory and stabilizing the final position of the load at the end of motion in spite of the flexibility of the support. The results of numerical calculations and possible applications of models developed using artificial neural networks are also presented.
CHAOTIC MODELING AND SIMULATION IN ROTATION–TRANSLATION MODELS
Authors: SKIADAS CHRISTOS H. , SKIADAS CHARILAOS
Published: September 2011

Chaotic modeling and simulation is a fast growing field that influences the world around us, and consequently also influences our ways of approaching, analyzing and solving problems. In this paper the rotation–translation case is presented based on the theory analyzed in the book — Chaotic Modeling and Simulation: Analysis of Chaotic Models, Attractors and Forms published by the above authors [Skiadas & Skiadas, 2008]. An overview of the chaotic flows in rotation–translation is given. Special cases and illustrations of chaotic attractors and forms are presented and a method of comparative presentation and analysis of the flows by using both continuous and discrete methods is applied by deriving the appropriate differential and difference equations' analogue. Furthermore, an analysis of chaotic attractors resulting in the models proposed is given along with an exploration of the characteristic or equilibrium points.
DYNAMICAL INSTABILITY ANALYSIS OF NANOTUBES USING NONLOCAL SHEAR BEAM THEORY
Authors: TYLIKOWSKI ANDRZEJ
Published: September 2011

The dynamics stability of distributed systems (continua) has been an object of considerable attention over the past half century. Numerous papers are available on isotropic and laminated beams, shafts, plates and shells under periodic and random forces. Most papers have applied finite dimensional or modal approximations in the analysis of vibration and stability. This paper focuses on the stochastic parametric vibrations of micro- and nanorods based on Eringens nonlocal elasticity theory and shear beam theory. The almost sure asymptotic instability criteria involving a damping coefficient, structure and loading parameters are derived using Liapunov's direct method. Using the appropriate energy-like Liapunov functional, sufficient conditions for the almost sure asymptotic instability of undeflected form of beam are derived. The nonlocal shear beam accounts for the scale effect, which becomes significant when dealing with short micro- and nanorods. From the obtained analytical formulas it is clearly seen that the small scale effect increases the dynamic instability region. Instability regions are functions of the axial force variance, the constant component of axial force and the damping coefficient.
AN INTEGRATIVE MODEL FOR THE DEVELOPMENT OF EMERGING TECHNOLOGY COMPLEX
Authors: LAU THERESA , CHAN K. F.
Published: September 2011

The term emerging technology complex (ETC) is associated with companies that wish to diversify into a technology related business by setting up a new venture in parallel with their existing core business. ETC strategy has been widely adopted by many traditional companies due to the advance of technology and the changing market environment, but its resulting performance varies depending largely on how it is operated, i.e. the internal factors. This study explored which of these internal factors are important in affecting the development and growth of ETCs. Four companies with ETC setup were selected for the study; two were more successful while two were less successful. In-depth semi-structured interviews were conducted. The findings indicate that the success of ETC is due to internal co-operation in an entrepreneurial environment and the implementation of an organic organisational form. A development model for successful ETC is recommended in the conclusion of the paper.
ENTREPRENEURSHIP THROUGH THE AGES: LESSONS LEARNED
Authors: ARTHUR STEPHANIE J. , HISRICH ROBERT D.
Published: September 2011

In today's hypercompetitive environment, the notion of entrepreneurship, entrepreneurial leadership and entrepreneurial decision-making is receiving increased attention by citizens, academics, managers, and politicians on a global basis. The high failure rate of entrepreneurship of new ventures as well as new products indicates that many barriers to success exist; however, even entrepreneurship on a small scale can have great impact. A historical review reveals that entrepreneurs emerge from various backgrounds but have similar characteristics. The time is ripe for the acceleration of entrepreneurial behavior and leadership that will facilitate new venture creation that will in turn nurture the growth of jobs and the local economy.
ON LÖWENHEIM–SKOLEM–TARSKI NUMBERS FOR EXTENSIONS OF FIRST ORDER LOGIC
Authors: MAGIDOR MENACHEM , VÄÄNÄNEN JOUKO
Published: September 2011

We show that, assuming the consistency of a supercompact cardinal, the first (weakly) inaccessible cardinal can satisfy a strong form of a Löwenheim–Skolem–Tarski theorem for the equicardinality logic L(I), a logic introduced in [5] strictly between first order logic and second order logic. On the other hand we show that in the light of present day inner model technology, nothing short of a supercompact cardinal suffices for this result. In particular, we show that the Löwenheim–Skolem–Tarski theorem for the equicardinality logic at κ implies the Singular Cardinals Hypothesis above κ as well as Projective Determinacy.
Noninvasive quantification of left ventricular elastance and ventricular-arterial coupling using three-dimensional echocardiography and arterial tonometry
Authors: Gayat Etienne , Mor-Avi Victor , Weinert Lynn , Yodwut Chattanong , Lang Roberto M.
Published: September 2011

Most techniques previously used to assess left ventricular (LV) end-systolic elastance (Ees) and ventricular-arterial coupling (CLV-A) relied on invasive measurements and data acquisition over a wide range of loading conditions. Our goals were to 1) assess the feasibility of noninvasive assessment of Ees and CLV-A using real-time three-dimensional echocardiography (RT3DE) and arterial tonometry; 2) test the ability of this approach to detect changes in LV contractility; and 3) study its reproducibility. We studied pharmacologically induced changes in inotropic state (5 and 10 μg·kg−1·min−1 dobutamine) in normal volunteers ( N = 8) and compared 10 normal volunteers with 10 patients with dilated cardiomyopathy (DCM; ejection fraction < 35%). RT3DE LV images, calibrated carotid artery tonometry, and Doppler tracings were obtained to noninvasively estimate Ees and CLV-A, using two alternative calculations. Dobutamine caused a significant stepwise increase in blood pressure, heart rate, ejection fraction, and Ees and a decreased CLV-A. In patients with DCM, Ees was significantly reduced and CLV-A elevated, compared with controls. Both inter- and intraobserver variability were good for all measured parameters, as reflected by intraclass correlation coefficients (>0.8) and coefficients of variation (<20%). While both Ees estimates showed significant differences between DCM patients and controls, one estimate resulted in no overlap and better reproducibility (interobserver intraclass correlation coefficient: 0.83 vs. 0.47, coefficients of variation: 20 vs. 29%). This is the first study to test the feasibility of using RT3DE-derived LV volumes in conjunction with arterial tonometry to noninvasively quantify LV elastance and CLV-A. This approach was found to be sensitive enough to detect expected differences in LV contractility and reproducible. Due to its noninvasive nature, this methodology may have clinical implications in various disease states.
Eosinophils are necessary for pulmonary arterial remodeling in a mouse model of eosinophilic inflammation-induced pulmonary hypertension
Authors: Weng M. , Baron D. M. , Bloch K. D. , Luster A. D. , Lee J. J. , Medoff B. D.
Published: September 2011

There is increasing evidence that inflammation plays a pivotal role in the pathogenesis of some forms of pulmonary hypertension (PH). We recently demonstrated that deficiency of adiponectin (APN) in a mouse model of PH induced by eosinophilic inflammation increases pulmonary arterial remodeling, pulmonary pressures, and the accumulation of eosinophils in the lung. Based on these data, we hypothesized that APN deficiency exacerbates PH indirectly by increasing eosinophil recruitment. Herein, we examined the role of eosinophils in the development of inflammation-induced PH. Elimination of eosinophils in APN-deficient mice by treatment with anti-interleukin-5 antibody attenuated pulmonary arterial muscularization and PH. In addition, we observed that transgenic mice that are devoid of eosinophils also do not develop pulmonary arterial muscularization in eosinophilic inflammation-induced PH. To investigate the mechanism by which APN deficiency increased eosinophil accumulation in response to an allergic inflammatory stimulus, we measured expression levels of the eosinophil-specific chemokines in alveolar macrophages isolated from the lungs of mice with eosinophilic inflammation-induced PH. In these experiments, the levels of CCL11 and CCL24 were higher in macrophages isolated from APN-deficient mice than in macrophages from wild-type mice. Finally, we demonstrate that the extracts of eosinophil granules promoted the proliferation of pulmonary arterial smooth muscle cells in vitro. These data suggest that APN deficiency may exacerbate PH, in part, by increasing eosinophil recruitment into the lung and that eosinophils could play an important role in the pathogenesis of inflammation-induced PH. These results may have implications for the pathogenesis and treatment of PH caused by vascular inflammation.
Regulation of normal and cystic fibrosis airway epithelial repair processes by TNF-α after injury
Authors: Maillé Emilie , Trinh Nguyen Thu Ngan , Privé Anik , Bilodeau Claudia , Bissonnette Élyse , Grandvaux Nathalie , Brochiero Emmanuelle
Published: September 2011

Chronic infection and inflammation have been associated with progressive airway epithelial damage in patients with cystic fibrosis (CF). However, the effect of inflammatory products on the repair capacity of respiratory epithelia is unclear. Our objective was to study the regulation of repair mechanisms by tumor necrosis factor-α (TNF-α), a major component of inflammation in CF, in a model of mechanical wounding, in two bronchial cell lines, non-CF NuLi and CF CuFi. We observed that TNF-α enhanced the NuLi and CuFi repair rates. Chronic exposure (24–48 h) to TNF-α augmented this stimulation as well as the migration rate during repair. The cellular mechanisms involved in this stimulation were then evaluated. First, we discerned that TNF-α induced metalloproteinase-9 release, epidermal growth factor (EGF) shedding, and subsequent EGF receptor transactivation. Second, TNF-α-induced stimulation of the NuLi and CuFi wound-closure rates was prevented by GM6001 (metalloproteinase inhibitor), EGF antibody (to titrate secreted EGF), and EGF receptor tyrosine kinase inhibitors. Furthermore, we recently reported a relationship between the EGF response and K+channel function, both controlling bronchial repair. We now show that TNF-α enhances KvLQT1 and KATPcurrents, while their inhibition abolishes TNF-α-induced repair stimulation. These results indicate that the effect of TNF-α is mediated, at least in part, through EGF receptor transactivation and K+channel stimulation. In contrast, cell proliferation during repair was slowed by TNF-α, suggesting that TNF-α could exert contrasting actions on repair mechanisms of CF airway epithelia. Finally, the stimulatory effect of TNF-α on airway wound repair was confirmed on primary airway epithelial cells, from non-CF and CF patients.
Phase Behaviour of 1‐Ethyl‐3‐methylimidazolium Thiocyanate Ionic Liquid with Catalytic Deactivated Compounds and Water at Several Temperatures: Experiments and Theoretical Predictions
Authors: Anantharaj Ramalingam , Banerjee Tamal
Published: September 2011

Density, surface tension and refractive index were determined for the binary mixture of catalytic deactivated compounds with 1‐ethyl‐3‐methylimidazolium thiocyanate {[EMIM][SCN]} at temperature of (298.15 to 323.15) K. For all the compounds with ILs, the densities varied linearly in the entire mole fraction with increasing temperature. From the obtained data, the excess molar volume and deviation of surface tension and refractive index have been calculated. A strong interaction was found between similar (cation‐thiophene or cation‐pyrrole) compounds. The interaction of IL with dissimilar compounds such as indoline and quinoline and other multiple ring compounds was found to strongly depend on the composition of IL at any temperatures. For the mixtures, the surface tension decreases in the order of: thiophene > quinoline > pyridine > indoline > pyrrole > water. In general from the excess volume studies, the IL‐sulphur/nitrogen mixture has stronger interaction as compared to IL‐IL, thiophene‐thiophene or pyrrole‐pyrrole interaction. The deviation of surface tension was found to be inversely proportional to deviation of refractive index. The quantum chemical based COSMO‐RS was used to predict the non‐ideal liquid phase activity coefficient for all mixtures. It indicated an inverse relation between activity coefficient and excess molar volumes.
Anomalous Right Coronary Artery: A Multimodality Hunt for the Origin
Authors: Gilmour J. , Kafka H. , Ropchan G. , Johri A. M.
Published: September 2011

Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is a rare congenital anomaly. Although there have been several cases of ARCAPA reported in the literature, we present a case which highlights the challenges of diagnosing this rare condition and the incremental value of using multiple imaging modalities. A healthy 48 year old female presented with angina and exertional shortness of breath. She had a normal cardiovascular examination, negative cardiac enzymes and an unremarkable chest X-ray. She did, however, have T-wave inversions in leads V1–V3. Transthoracic echocardiography (TTE), as the first imaging investigation, led to an initial provisional diagnosis of a coronary-cameral fistula. It showed unusual colour Doppler signals in the right ventricle and a prominent pattern of diastolic flow within the right ventricular myocardium, especially along the interventricular septum. A subsequent multimodality approach, correlating images from angiography, CT and MRI was instrumental in confirming the diagnosis of ARCAPA and planning for surgical correction. Cardiac CT and MRI are non-invasive, three-dimensional imaging modalities with high diagnostic accuracy for coronary artery anatomic anomalies. If echocardiography and conventional angiography have been inconclusive, cardiac CT and MRI are especially important diagnostic tools.
Primary Breast Angiosarcoma: Avoiding a Common Trap
Authors: Desbiens Christine , Hogue Jean-Charles , Lévesque Yves
Published: September 2011

Background. Primary breast angiosarcoma is a rare entity.Case. Initial diagnosis was a benign hemangioma at core biopsy. Wide local excision was performed, with positive margins. Pathology after surgery reported a moderately differentiated angiosarcoma. Tumor was finally treated using mastectomy and radiations. She developed a second angiosarcoma in contralateral breast, with an initial diagnosis on core biopsy of an atypical vascular lesion and was again treated using mastectomy and radiations. She developed bones and lung metastases.Conclusion. Primary breast angiosarcoma is a rare entity often difficult to diagnose on core biopsy, and a benign differential diagnosis is frequent. A highly vascular breast mass should always be considered malignant until proven otherwise. Surgical treatment seems to be the best course of action. There is a lack of data proving efficacy of adjuvant chemotherapy and radiation therapy.
Positive Almost Periodic Solution on a Nonlinear Differential Equation
Authors: Hua Ni , Li-xin Tian , Xun Liu
Published: September 2011

We study the following nonlinear equation dx(t)/dt = x(t)[a(t) − b(t)xα(t) − f(t, x(t))] + g(t), by using fixed point theorem, the sufficient conditions of the existence of a unique positive almost periodic solution for above system are obtained, by using the theories of stability, the sufficient conditions which guarantee the stability of the unique positive almost periodic solution are derived.
A Novel Microduplication in the Neurodevelopmental GeneSRGAP3That Segregates with Psychotic Illness in the Family of a COS Proband
Authors: Wilson Nicole K. A. , Lee Yohan , Long Robert , Hermetz Karen , Rudd M. Katharine , Miller Rachel , Rapoport Judith L. , Addington Anjené M.
Published: September 2011

Schizophrenia is a debilitating mental disorder affecting approximately 1% of the world's population. Childhood onset schizophrenia (COS), defined as onset before age 13, is a rare and severe form of the illness that may have more salient genetic influence. We identified a ~134 kb duplication spanning exons 2–4 of theSlit-Robo GTPase-activating protein 3(SRGAP3) gene on chromosome 3p25.3 that tracks with psychotic illness in the family of a COS proband. Cloning and sequencing of the duplication junction confirmed that the duplication is tandem, and analysis of the resulting mRNA transcript suggests that the duplication would result in a frame shift mutation. This is the first family report of aSRGAP3copy number variant (CNV) in schizophrenia. Considering thatSRGAP3is important in neural development, we conclude that thisSRGAP3duplication may be an important factor contributing to the psychotic phenotype in this family.
Open-Loop Beamforming Technique for MIMO System and Its Practical Realization
Authors: Uthansakul Peerapong , Innok Apinya , Uthansakul Monthippa
Published: September 2011

The concept of close-loop beamforming for MIMO system was well known proposed the singular value decomposition on channel matrix. This technique can improve the capacity performance, but the cost of feedback channel and the complexity processing discard the interest of implementation. Therefore, this paper aims to investigate the benefit of using an open-loop beamforming for MIMO system in practical approaches. The low-profile concept of open-loop beamforming which is convenient for implementation is proposed by just inserting Butler matrices at both transmitter and receiver. The simulation and measurement results indicate that the open-loop beamforming with Butler matrix outperforms the conventional MIMO system. Although, the close-loop beamforming offers a better performance than open-loop beamforming technique, the proposed system is attractive because it is low cost, uncomplicated, and easy to implement.
An Inventory System for Deteriorating Products with Ramp-Type Demand Rate under Two-Level Trade Credit Financing
Authors: Darzanou G. , Skouri K.
Published: September 2011

An inventory system for deteriorating products, with ramp-type demand rate, under two-level trade credit policy is considered. Shortages are allowed and partially backlogged. Sufficient conditions of the existence and uniqueness of the optimal replenishment policy are provided, and an algorithm, for its determination, is proposed. Numerical examples highlight the obtained results, and sensitivity analysis of the optimal solution with respect to major parameters of the system is carried out.
Basal and Frontal Accretion Processes versus BSR Characteristics along the Chilean Margin
Authors: Vargas-Cordero I. , Tinivella U. , Accaino F. , Fanucci F. , Loreto M. F. , Lascano M. E. , Reichert C.
Published: September 2011

Multichannel seismic reflection data recorded between Itata (36°S) and Coyhaique offshores (43°S) were processed to obtain seismic images. Analysis of the seismic profiles revealed that weak and discontinuous bottom simulating reflectors were associated to basal accretion processes, while strong and continuous bottom simulating reflectors were associated to frontal accretion processes. This can be explained considering that during basal accretion processes, extensional tectonic movements due to uplifting can favour fluid escapes giving origin to weaker and most discontinuous bottom simulating reflectors. During frontal accretion processes (folding and thrusting), high fluid circulation and stable tectonic conditions however can be responsible of stronger and most continuous bottom simulating reflectors. Along the Arauco-Valdivia offshores, steep accretionary prisms, normal faults, slope basins, and thicker underplated sediment bed were associated to basal accretion, while along the Itata, Chiloe and Coyhaique offshores, small accretionary prisms, folding, and thinner underplated sediment bed were associated to frontal accretion.
Totally Umbilical Hemi‐Slant Submanifolds of Kaehler Manifolds
Authors: Al-Solamy Falleh R. , Khan Meraj Ali , Uddin Siraj
Published: September 2011

We study totally umbilical hemi‐slant submanifolds of a Kaehler manifold via curvature tensor. We prove some classification theorems for totally umbilical hemi‐slant submanifolds of a Kaehler manifold and give an example.
Impaired Economy of Gait and Decreased Six-Minute Walk Distance in Parkinson's Disease
Authors: Katzel Leslie I. , Ivey Frederick M. , Sorkin John D. , Macko Richard F. , Smith Barbara , Shulman Lisa M.
Published: September 2011

Changes in the biomechanics of gait may alter the energy requirements of walking in Parkinson's Disease (PD). This study investigated economy of gait during submaximal treadmill walking in 79 subjects with mild to moderate PD and the relationship between gait economy and 6-minute walk distance (6 MW). Oxygen consumption (VO2) at the self-selected treadmill walking speed averaged 64% of peak oxygen consumption (VO2peak). Submaximal VO2levels exceeded 70% of VO2peak in 30% of the subjects. Overall the mean submaximal VO2was 51% higher than VO2levels expected for the speed and grade consistent with severe impairment in economy of gait. There was an inverse relationship between economy of gait and 6MW (r=−0.31,P<0.01) and with the self-selected walking speed (r=−0.35,P<0.01). Thus, the impairment in economy of gait and decreased physiologic reserve result in routine walking being performed at a high percentage of VO2peak.
Exercise and Omega-3 Polyunsaturated Fatty Acid Supplementation for the Treatment of Hepatic Steatosis in Hyperphagic OLETF Rats
Authors: Borengasser Sarah J. , Rector R. Scott , Uptergrove Grace M. , Morris E. Matthew , Perfield James W. , Booth Frank W. , Fritsche Kevin L. , Ibdah Jamal A. , Thyfault John P.
Published: September 2011

Background and Aims.This study examined if exercise and omega-3 fatty acid (n3PUFA) supplementation is an effective treatment for hepatic steatosis in obese, hyperphagic Otsuka Long-Evans Tokushima Fatty (OLETF) rats.Methods.Male OLETF rats were divided into 4 groups (n=8/group): (1) remained sedentary (SED), (2) access to running wheels; (EX) (3) a diet supplemented with 3% of energy from fish oil (n3PUFA-SED); and (4) n3PUFA supplementation plus EX (n3PUFA+EX). The 8 week treatments began at 13 weeks, when hepatic steatosis is present in OLETF-SED rats.Results.EX alone lowered hepatic triglyceride (TAG) while, in contrast, n3PUFAs failed to lower hepatic TAG and blunted the ability of EX to decrease hepatic TAG levels in n3PUFAs+EX. Insulin sensitivity was improved in EX animals, to a lesser extent in n3PUFA+EX rats, and did not differ between n3PUFA-SED and SED rats. Only the EX group displayed higher complete hepatic fatty acid oxidation (FAO) to CO2and carnitine palmitoyl transferase-1 activity. EX also lowered hepatic fatty acid synthase protein while both EX and n3PUFA+EX decreased stearoyl CoA desaturase-1 protein.Conclusions.Exercise lowers hepatic steatosis through increased complete hepatic FAO, insulin sensitivity, and reduced expression ofde novofatty acid synthesis proteins while n3PUFAs had no effect.
Expression of ERβ and Its Co-Regulators p300 and NCoR in Human Transitional Cell Bladder Cancer
Authors: Kontos Stylianos , Papatsoris Athanasios , Kominea Athina , Melachrinou Maria , Tanoglidi Anna , Kachrilas Stefanos , Karavitakis Markos , Balampani Eleni , Sotiropoulou-Bonikou Georgia
Published: September 2011

Objective: Several data support a possible role of estrogens in bladder carcinogenesis, mediated mainly through estrogen receptor-β (ERβ). We study the expression of ERβ and its co-regulators p300 and nuclear co-repressor (NCoR) in patients with bladder cancer. Patients and Methods: One hundred and eleven consecutive patients (74 males and 37 females), aged 23–90 years (mean 70 ± 10) diagnosed with transitional cell bladder cancer were included in this study. The control group consisted of 29 patients that underwent transurethral prostatectomy and consented to simultaneous bladder biopsies. Immunohistochemical studies took place on formalin-fixed, paraffin-embedded sections from the TUR (transurethral resection) specimens. We studied the expression of ERβ, p300 and NCoR.χ2 test was used to evaluate the relationship between the histological grade and ERβ expression, grade and co-regulators expression and grade and gender. Spearman rank correlation coefficient (r) was used in order to estimate the direction and strength of correlations between histological grade and ERβ-p300-NCoR expressions. The Cochran-Armitage test for trend was applied in order to examine possible trends across the ordered levels of histological grade. Results: ERβ was more frequently expressed in the nucleus of normal bladder epithelium compared to malignant bladder epithelium with statistical significant association (r = –0.25, p = 0.003). The p300 was expressed only in the nucleus of bladder cancer cells and a positive correlation between molecular expression and cancer progression was demonstrated (r = 0.55, p < 0.001). NCoR immunostaining was demonstrated in the nuclei of bladder cells. Nuclear staining was significantly higher in normal tissue than in cancer cells (r = –0.33, p < 0.001), with negative correlation. Furthermore, its expression in grade I tumors was significantly higher than in grade II (r = –0.46, p < 0.001) and grade III tumors (r = –0.51, p < 0.001). Thus, like ERβ, NCoR expression in bladder epithelium decreased during cancer progression and loss of cell differentiation. There was no correlation between the levels of expression of the three proteins in normal bladder epithelium, but there was an inverse correlation between the nuclear expression of ERβ and p300 in carcinomas (r = –3.88, p = 0.042). Statistical significant association was established when correlating ERβ expression with NCoR expression (r = 0.273, p = 0.005), while co-regulators’ nuclear expression did not correlate with each other (p > 0.05). Conclusions: In bladder carcinogenesis, we demonstrated inhibition in the expression of ERβ and its co-repressor NCoR as well as increased expression of the co-activator p300.
Inhibition of the Experimental Induction of Benign Prostatic Hyperplasia: A Possible Role for Fluted Pumpkin (Telfairia occidentalis Hook f.) Seeds
Authors: Ejike Chukwunonso E.C.C. , Ezeanyika Lawrence U.S.
Published: September 2011

Introduction: Pumpkins are thought to be useful in the management of benign prostatic hyperplasia (BPH). The ability of a 15% Telfairia occidentalis seeds incorporated diet to inhibit hormonal induction of BPH in rats was studied. Materials and Methods: Twenty male Wistar rats were divided into 4 equal groups – one test group and three control groups. The test group was placed on the test diet and was given subcutaneous injections of dihydrotestosterone (DHT) and estradiol valerate (ratio 10:1) every other day for 28 days. One control group, ‘no test diet’ (ND) group, received the hormones, but was placed on a normal diet. The other two control groups, ‘no hormone’ (NH) and ‘no hormone/test diet’ (NHD), received subcutaneous olive oil (vehicle) for the same duration and were placed on the test and normal diets, respectively. Markers of BPH and hormone profile were determined using standard methods. Results: The mean relative prostate weight (×103) was reduced in the test group (3.6 ± 0.2) relative to the ND group (4.0 ± 0.4). The protein content (mg/tissue) of the rats’ prostates decreased significantly (p < 0.05) from 68.3 ± 2.7 in the ND group to 43.4 ± 3.9 in the test group. Serum prostatic acid phosphatase levels (U/l) decreased significantly (p < 0.05) from 4.8 ± 0.4 in the ND group to 4.0 ± 0.9 in the test group. Histological findings corroborate these data. The testosterone:estradiol ratio (×103) was significantly (p < 0.05) increased from 7.1 ± 0.1 in the ND group to 8.4 ± 0.4 in the test group. Conclusion: The test diet inhibited the induction of BPH in rats and may act by increasing the testosterone:estradiol ratio.