bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffractive results from CDF
Authors: Goulianos Konstantin
Published: February 2015

We present a reference review of diffractive results from CDF for [Formula: see text] collisions at [Formula: see text], 630, 1800, and 1960 GeV at the Tevatron, published in 19 PRL/PRD papers from 1994 to 2012. Both soft and hard diffractive results are included for single and/or double dissociation, central diffraction or double Pomeron exchange (where both the proton and antiproton remain intact), multi-gap diffraction (a combination of single and double dissociation), elastic scattering, and the total cross-section, which through the optical theorem is related to the imaginary part of the forward elastic scattering amplitude. In each review, we include the comparisons made by CDF with theoretical predictions.
Do we understand near-forward elastic scattering up to TeV energies?
Authors: Bourrely Claude , Soffer Jacques , Wu Tai Tsun
Published: February 2015

In 1970, on purely theoretical grounds, all total hadronic total cross-sections were predicted to increase without limit for higher and higher energies. This was contrary to the conventional belief at that time. In 1978, an accurate phenomenological model was formulated for the case of proton–proton and antiproton-proton interactions. The parameters for this model were slightly improved in 1984 using the additional available experimental data. Since then, for 30 years these parameters have not changed. This development, including especially the difficult task of formulating this phenomenological model and the comparison of the predictions of this model with later experimental results, is summarized.
Existence of Perpetual Points in Nonlinear Dynamical Systems and Its Applications
Authors: Prasad Awadhesh
Published: February 2015

A new class of critical points, termed as perpetual points, where acceleration becomes zero but the velocity remains nonzero, are observed in dynamical systems. The velocity at these points is either maximum or minimum or of inflection behavior. These points also show the bifurcation behavior as the parameters of the system vary. These perpetual points are useful for locating the hidden oscillating attractors as well as coexisting attractors. Results show that these points are important for a better understanding of transient dynamics in the phase space. The existence of these points confirms whether a system is dissipative or not. Various examples are presented, and the results are discussed analytically as well as numerically.
Bifurcation Analysis of Fractional Order Single Cell with Delay
Authors: Çelik Vedat
Published: February 2015

This paper presents the bifurcation analysis of fractional order model of delayed single cell which is proposed for delayed cellular neural networks with respect to the time delay τ. The bifurcation points, time delay τc, are determined by modified Mikhailov stability criterion for a range of fractional delayed cell order 0.3 ≤ q < 1. Numerical results obtained from Adams–Bashforth–Moulton method demonstrate that the supercritical Hopf bifurcation occurs in the system.
Melnikov-Type Chaos of Planar Systems with Two Discontinuities
Authors: Castro Jose , Alvarez Joaquin
Published: February 2015

In this paper, the chaotic behavior of a driven planar system with two discontinuous terms and a pseudo-equilibrium point in the intersection of the discontinuity surfaces is analyzed. This scenario is not covered by smooth techniques of chaos analysis or other techniques like the extension of Melnikov's method for nonsmooth systems. In consequence, we propose to use an approximate model of the discontinuous system for which this technique can be applied, and compare the responses of both systems, the discontinuous and the approximate, when this last model is close, in a certain way, to the discontinuous system. One of the discontinuous terms, given by a sign function, is approximated by a saturation with high slope at the equilibrium point. Some conditions that determine the chaotic behavior of the approximate system are formally established, and the convergence of its chaotic orbits to some orbits of the discontinuous system, when the slope of the approximation is large enough, is shown. In particular, we show the similarity of the dynamical behavior of both systems where a chaotic behavior can be displayed, for a parameter region determined by the application of the Melnikov technique to nonsmooth systems. A comparison of the Feigenbaum diagrams, for a parameter range obtained from the application of this technique, shows the similarity of their dynamics and the chaotic nature of the discontinuous system.
STUDY ON SOLIDIFICATION OF PHASE CHANGE MATERIAL IN FRACTAL POROUS METAL FOAM
Authors: ZHANG CHENGBIN , WU LIANGYU , CHEN YONGPING
Published: February 2015

The Sierpinski fractal is introduced to construct the porous metal foam. Based on this fractal description, an unsteady heat transfer model accompanied with solidification phase change in fractal porous metal foam embedded with phase change material (PCM) is developed and numerically analyzed. The heat transfer processes associated with solidification of PCM embedded in fractal structure is investigated and compared with that in single-pore structure. The results indicate that, for the solidification of phase change material in fractal porous metal foam, the PCM is dispersedly distributed in metal foam and the existence of porous metal matrix provides a fast heat flow channel both horizontally and vertically, which induces the enhancement of interstitial heat transfer between the solid matrix and PCM. The solidification performance of the PCM, which is represented by liquid fraction and solidification time, in fractal structure is superior to that in single-pore structure.
QUANTIFYING THE RELATIONSHIP BETWEEN DRAINAGE NETWORKS AT HILLSLOPE SCALE AND PARTICLE SIZE DISTRIBUTION AT PEDON SCALE
Authors: CÁMARA JOAQUÍN , MARTÍN MIGUEL ÁNGEL , GÓMEZ-MIGUEL VICENTE
Published: February 2015

Nowadays, translating information about hydrologic and soil properties and processes across scales has emerged as a major theme in soil science and hydrology, and suitable theories for upscaling or downscaling hydrologic and soil information are being looked forward. The recognition of low-order catchments as self-organized systems suggests the existence of a great amount of links at different scales between their elements. The objective of this work was to research in areas of homogeneous bedrock material, the relationship between the hierarchical structure of the drainage networks at hillslope scale and the heterogeneity of the particle-size distribution at pedon scale. One of the most innovative elements in this work is the choice of the parameters to quantify the organization level of the studied features. The fractal dimension has been selected to measure the hierarchical structure of the drainage networks, while the Balanced Entropy Index (BEI) has been the chosen parameter to quantify the heterogeneity of the particle-size distribution from textural data. These parameters have made it possible to establish quantifiable relationships between two features attached to different steps in the scale range. Results suggest that the bedrock lithology of the landscape constrains the architecture of the drainage networks developed on it and the particle soil distribution resulting in the fragmentation processes.
FRACTAL ANALYSIS OF GAS DIFFUSION IN POROUS NANOFIBERS
Authors: XIAO BOQI , FAN JINTU , WANG ZONGCHI , CAI XIN , ZHAO XIGE
Published: February 2015

In this study, with the consideration of pore size distribution and tortuosity of capillaries, the analytical model for gas diffusivity of porous nanofibers is derived based on fractal theory. The proposed fractal model for the normalized gas diffusivity (De/D0) is found to be a function of the porosity, the area fractal dimensions of pore and the fractal dimension of tortuous capillaries. It is found that the normalized gas diffusivity decreases with increasing of the tortuosity fractal dimension. However, the normalized gas diffusivity is positively correlated with the porosity. The prediction of the proposed fractal model for porous nanofibers with porosity less than 0.75 is highly consistent with the experimental and analytical results found in the literature. The model predictions are compared with the previously reported experimental data, and are in good agreement between the model predictions and experimental data is found. The validity of the present model is thus verified. Every parameter of the proposed formula of calculating the normalized gas diffusivity has clear physical meaning. The proposed fractal model can reveal the physical mechanisms of gas diffusion in porous nanofibers.
A NUMERICAL STUDY ON FRACTAL DIMENSIONS OF CURRENT STREAMLINES IN TWO-DIMENSIONAL AND THREE-DIMENSIONAL PORE FRACTAL MODELS OF POROUS MEDIA
Authors: WEI WEI , CAI JIANCHAO , HU XIANGYUN , FAN PING , HAN QI , LU JINGE , CHENG CHU-LIN , ZHOU FENG
Published: February 2015

The fractal dimension of random walker (FDRW) is an important parameter for description of electrical conductivity in porous media. However, it is somewhat empirical in nature to calculate FDRW. In this paper, a simple relation between FDRW and tortuosity fractal dimension (TFD) of current streamlines is derived, and a novel method of computing TFD for different generations of two-dimensional Sierpinski carpet and three-dimensional Sierpinski sponge models is presented through the finite element method, then the FDRW can be accordingly predicted; the proposed relation clearly shows that there exists a linear relation between pore fractal dimension (PFD) and TFD, which may have great potential in analysis of transport properties in fractal porous media.
STUDY ON THE RELATIONSHIP BETWEEN VALENCE ELECTRON STRUCTURE AND COATING ORIENTED GROWTH
Authors: TAN SHUYONG , ZHANG XUHAI , ZHEN RUI , ZHANG LEI , TIAN ZENG , BA ZHIXIN , WANG ZHANGZHONG
Published: February 2015

The coating oriented growth has attracted great attention because of its effect on coating properties. In this paper, the valence electron structures of TiN and Ni were calculated with the empirical electron theory (EET) in solid and molecules for investigating preferred orientation of nitride coatings containing Ni . The calculation results show that Ni (111), CrN (100) and TiN (100) are the maximum crystal-face electron density, respectively. In CrN (or TiN ) coatings, if Ni does not form a single nickel phase, CrN (100) (or TiN (100)) preferred orientation appears easily due to its high crystal-face electron density. When Ni exists as a single phase, CrN (100)/ Ni (111) (or TiN (100)/ Ni (111)) with the minimum crystal-face electron density difference is the most likely to appear in the coatings. Furthermore, high crystal-face electron density difference usually implies fine grain microstructure. The calculation results are consistent with the experimental results.
ELECTROKINETIC CHARACTERISTICS OF CALCINED KAOLINITE IN AQUEOUS ELECTROLYTIC SOLUTIONS
Authors: CHEN TIANXING , ZHAO YUNLIANG , LI HONGLIANG , LIU JIA , SONG SHAOXIAN
Published: February 2015

In this work, the electrokinetic characteristics of calcined kaolinite in aqueous solutions has been studied in the presence of the electrolytes of NaCl , KCl , NH 4 Cl , NaNO 3, MgCl 2, CaCl 2 and AlCl 3, through electrophoretic measurement. The experimental results have shown that the zeta potential was closely dependent on the valence and concentration of the electrolytic cations, but not on the type of the cations. The higher the valence and the concentration were, the stronger the impact to the zeta potential was. Al 3+ could reverse the potential sign from negative to positive. In addition, it was found that the monovalent anions of Cl - and [Formula: see text] made a big difference to the zeta potential at the same dosage.
Jyothy Stoops to Conquer: The Henkel India Acquisition
Authors: Dwivedi Neeraj , John Ben P.
Published: March 2015

In the year 2011, Jyothy Laboratories (Jyothy), a small domestic player in the Fast Moving Consumer Goods (FMCG) industry in India, acquired Henkel India. Having historically followed a purely organic strategy, Jyothy made a strategic shift, by acquiring Henkel India. The case describes the circumstances leading to this acquisition from the perspective of both Henkel and Jyothy. The case outlines the intricacies involved in the entire acquisition process including the strategic motives, regulatory issues, bargaining between the parties and the postacquisition phase. There were integration issues faced by both companies, specifically since Jyothy was an Indian company and Henkel India was part of a large European multinational. The main protagonist in the case has to address the challenges his company faces after the acquisition of Henkel India.
Multiresolution analysis for compactly supported interpolating tensor product wavelets
Authors: Höynälänmaa Tommi
Published: February 2015

We construct multidimensional interpolating tensor product multiresolution analyses (MRA's) of the function spaces C0(ℝn, K), K = ℝ or K = ℂ, consisting of real or complex valued functions on ℝn vanishing at infinity and the function spaces Cu(ℝn, K) consisting of bounded and uniformly continuous functions on ℝn. We also construct an interpolating dual MRA for both of these spaces. The theory of the tensor products of Banach spaces is used. We generalize the Besov space norm equivalence from the one-dimensional case to our n-dimensional construction.
ParaVoxel: A Domain Decomposition Based Fixed Grid Preprocessor
Authors: Garcia Manuel J. , Duque Juan , Henao Miguel , Boulanger Pierre
Published: February 2015

In this paper, a parallel cartesian fixed grid mesh generator for structural and fluid dynamics problems is presented. The method uses the boundary representation of a body and produces a set of equal sized cells which are classified in three different types according to its location with respect to the body. Cells are inside, outside or intersecting the boundary of the body. This classification is made by knowing the number of nodes of a cell that are inside body. That process is accomplished very efficiently as the nodes can be classified in batch. Once boundary cells are identified, its geometry is approximated by the convex hull of the nodes inside the body and the intersection points of the boundary against the cell edges. This paper presents the basics of the Fixed Grid Meshing algorithm, followed by some domain decomposition modifications and the data structures required for its parallel implementation. A set of examples and a brief discussion on the possibility of applying this algorithm together with other approaches is presented.
A method of 3D reconstruction based on panoramic cameras
Authors: Liang Hua-Gang , Qian Wen-Xiu , Liu Yong-Kui , Ru Feng
Published: March 2015

In this paper, a method of 3D reconstruction from two images acquired by two panoramic cameras is presented. Firstly, the features of the reconstruction object detected in each image are matched through the DP matching method. Secondly, optical correction is carried out on two cameras, and the internal parameters of panoramic cameras can be calculated. Finally, according to the calibration method, the geometric relationship between corresponding points in space and in two panoramic images is deduced. The results indicate that the method of 3D reconstruction based on two panoramic cameras is simple, and the accuracy can reach 98.82%.
Studies of phase transition and impedance behavior of Ba(Zr, Ti)O3 ceramics
Authors: Sateesh P. , Omprakash J. , Kumar G. S. , Prasad G.
Published: February 2015

Ceramic samples of Barium Zirconium Titanate ( BaZr x Ti 1-x O 3 ( BZT )) were synthesized by conventional solid-state reaction method with different concentrations of x(= 0.05 ( BZT1 ), 0.10 (BZT2), 0.15 (BZT3), 0.20 (BZT4), 0.25 (BZT5), 0.30 (BZT6)). Phase confirmation of the samples was done by X-ray diffraction (XRD) technique. All the compositions are in cubic structure. XRD pattern was recorded for samples sintered at different sintering temperatures. Lattice parameters increased with addition of Zr +4. Doping with Zr +4 into Barium titanate resulted in interesting changes of electrical properties (dielectric, impedance and ferroelectiricity). The strong influence of Zr doping on the phase transition characteristics of the BZT ceramics was studied from the dielectric response of the samples. Diffusivity of phase transition of the BZT ceramic samples increase with Zr +4 concentration, indicating changes from normal to diffuse transition to relaxor phase transition behavior. Impedance spectroscopy reveals the presence of temperature-dependent grain, grain boundary effects. Polarization–Electricfield (PE) loop measurements are also done on the samples.
Probe of the Band Structure of MBE Grown p-Type InMnAs at Ultrahigh Magnetic Fields
Authors: Sun Y. , Kyrychenko F. V. , Sanders G. D. , Stanton C. J. , Khodaparast G. A. , Kono J. , Matsuda Y. H. , Munekata H.
Published: February 2015

We present a theoretical and experimental study on electronic and magneto-optical properties of p-type paramagnetic InMnAs dilute magnetic semiconductor (DMS) alloys in ultrahigh (> 100 T) external magnetic fields (B). Theoretical calculations are based on an 8-band Pidgeon–Brown model which is generalized to include the wavevector dependence of the electronic states along B as well as s–d and p–d exchange interactions with localized Mn d-electrons. The spin-dependent electronic structure as a function of Mn doping is computed and the dependence of the valence band structure on parameters such as the sp–d exchange interaction strength and effective masses in paramagnetic p- InMnAs alloys are examined. The cyclotron resonance (CR) and magneto-optical properties of InMnAs are calculated using Fermi's golden rule. Two strong CR peaks are observed in p-type InMnAs alloys which correspond to the transitions within either heavy-hole (HH) or light-hole (LH) Landau levels. Furthermore, we also observed strong resonance absorption for electron-active polarization which can occur in p-type semiconductors originating from transitions between the light and heavy hole Landau levels.
Sampling unitary ensembles
Authors: Olver Sheehan , Nadakuditi Raj Rao , Trogdon Thomas
Published: February 2015

We develop a computationally efficient algorithm for sampling from a broad class of unitary random matrix ensembles that includes but goes well beyond the straightforward to sample Gaussian unitary ensemble (GUE). The algorithm exploits the fact that the eigenvalues of unitary ensembles (UEs) can be represented as a determinantal point process whose kernel is given in terms of orthogonal polynomials. Consequently, our algorithm can be used to sample from UEs for which the associated orthogonal polynomials can be numerically computed efficiently. By facilitating high accuracy sampling of non-classical UEs, the algorithm can aid in the experimentation-based formulation or refutation of universality conjectures involving eigenvalue statistics that might presently be unamenable to theoretical analysis. Examples of such experiments are included.
Alcohol impairs insulin and IGF-I stimulation of S6K1 but not 4E-BP1 in skeletal muscle
Authors: Kumar Vinayshree , Frost Robert A. , Lang Charles H.
Published: March 2015

The present study determined whether acute alcohol (ethanol; EtOH) intoxication in rats impaired components of the insulin- and IGF-I-signaling pathway in skeletal muscle. Rats were administered EtOH, and 2.5 h thereafter either insulin, IGF-I, or saline was injected and the gastrocnemius removed. EtOH did not alter the total amount or tyrosine phosphorylation of the insulin receptor, IGF-I receptor, insulin receptor substrate (IRS)-1, or protein kinase B (PKB)/Akt under basal or hormone-stimulated conditions. In contrast, the ability of insulin or IGF-I to phosphorylate T389 and T421/S424 on S6K-1 was markedly diminished by EtOH, and these changes were associated with a reduction in the phosphorylation of the ribosomal protein S6. Under basal conditions, EtOH altered the distribution of eukaryotic initiation factor (eIF)4E, as evidenced by a decreased amount of active eIF4E  · eIF4G complex, an increased amount of inactive eIF4E  · 4E-binding protein (BP)1 complex, and decreased 4E-BP1 phosphorylation. In contrast, EtOH did not impair the ability of either hormone to reverse the changes in eIF4E distribution or 4E-BP1 phosphorylation. Pretreatment with a glucocorticoid receptor antagonist was unable to attenuate either the basal EtOH-induced changes in eIF4E distribution or the impaired ability of IGF-I to stimulate S6K1 and S6 phosphorylation. Hence, acute alcohol intoxication alters selected aspects of translational control under both basal and anabolic hormone-stimulated conditions in skeletal muscle in a glucocorticoid-independent manner.
Loss of survival factors and activation of inflammatory cascades in brain sympathetic centers in type 1 diabetic mice
Authors: Hu Ping , Thinschmidt Jeffrey S. , Caballero Sergio , Adamson Samuel , Cole Louise , Chan-Ling Tailoi , Grant Maria B.
Published: February 2015

Neuroinflammation and neurodegeneration have been observed in the brain in type 1 diabetes (T1D). However, little is known about the mediators of these effects. In T1D mice with 12- and 35-wk duration of diabetes we examined two mechanisms of neurodegeneration, loss of the neuroprotective factors insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) and changes in indoleamine 2,3-dioxygenase (IDO) expression in the brain, and compared the response to age-matched controls. Furthermore, levels of matrix metalloproteinase-2 (MMP-2), nucleoside triphosphate diphosphohydrolase-1 (CD39), and ionized calcium-binding adaptor molecule 1 (Iba-1) were utilized to assess inflammatory changes in astrocytes, microglia, and blood vessels. In the diabetic hypothalamus (HYPO), we observed 20% reduction in neuronal soma diameter ( P < 0.05) and reduced neuronal expression of IGFBP-3 (−32%, P < 0.05) and IGF-I (−15%, P < 0.05) compared with controls at 35 wk. In diabetic HYPO, MMP-2 expression was increased in astrocytes (46%, P < 0.01), and IDO+cell density rose by (62%, P < 0.05). CD39 expression dropped by 30% ( P < 0.05) in microglia and blood vessels. With 10 wk of systemic treatment using minocycline, an anti-inflammatory agent that crosses the blood-brain barrier, MMP-2, IDO, and CD39 levels normalized ( P < 0.05). Our results suggest that increased IDO and early loss of CD39+protective cells lead to activation of inflammation in sympathetic centers of the CNS. As a downstream effect, the loss of the neuronal survival factors IGFBP-3 and IGF-I and the neurotoxic products of the kynurenine pathway contribute to the loss of neuronal density observed in the HYPO in T1D.
Amino acid control of the human glyceraldehyde 3-phosphate dehydrogenase gene transcription in hepatocyte
Authors: Claeyssens Sophie , Gangneux Christophe , Brasse-Lagnel Carole , Ruminy Philippe , Aki Toshihiko , Lavoinne Alain , Salier Jean-Philippe
Published: March 2015

Glutamine (Gln) is the most potent of the amino acids (AAs) that regulate liver anabolism, and its effect is similar to that of insulin in peripheral tissues. However, the influence of AAs on regulation of metabolic enzyme-encoding genes is not known at the molecular level in liver. We now report that Gln and some essential AAs activate the human GAPDH gene that codes for GAPDH, a central enzyme of glycolysis and a target for insulin regulation. In HepG2 cells, Gln upregulated the GAPDH mRNA level, and this effect was additive to that of insulin. Transient transfection of GAPDH promoter/ cat constructs demonstrated that a gene-specific and insulin-independent transcriptional step is involved in the Gln responsiveness of GAPDH. Transfected HepG2 cells challenged with various AAs, Gln metabolites or inhibitors of Gln metabolism showed that the Gln-induced effect is similar to that of some essential AAs and that Gln metabolism is a necessary step for GAPDH activation. Deletion mutants and site-directed mutagenesis of the GAPDH promoter indicated that the Gln responsiveness is mediated by a sequence that is distinct from insulin-responsive elements and from positively acting elements previously described in this promoter. This motif located at -126/-118 clearly differs from AA-responsive elements recently identified in other genes. Electromobility shift assay and supershifts showed that the transcription factors bound to the Gln-responsive element in the GAPDH promoter are C/EBPα and -δ. This finding is consistent with the role of C/EBP family members in controlling the hepatic expression of genes involved in nutrient metabolism.
The water load test: observations from healthy controls and patients with functional dyspepsia
Authors: Jones Michael P. , Hoffman Seth , Shah Dhiren , Patel Ketan , Ebert Christine C.
Published: March 2015

Gastric sensation and accommodation are studied by barostat, but this is invasive. The drink test is noninvasive and may provide similar information. We evaluated relationships between drink test, gastric function, symptoms, and psychiatric distress. Controls (73) and functional dyspeptics (FD) (92) were studied using a 5-min water load test (WL5), gastric emptying, and electrogastrography (EGG). Symptoms, quality of life, and psychiatric distress were measured using standardized measures. Controls underwent test-retest of WL5 and comparison of WL5 with 100 ml/min water-based drink test (WL100) or nutrient drink. Controls, FD, and gastroparetics estimated drinking capacity before WL5 using a visual analog scale. WL5 correlated with WL100 ( r = 0.7929) but not nutrient drink test ( r = 0.1995). WL5 was significantly less in FD than controls, and abnormal WL5 was seen in 46%. In FD, volume to fullness inversely correlated with symptom severity ( r =−0.29; P = 0.0154) and WL5 produced more symptoms, particularly nausea. Gastric function was not different between FD with normal or abnormal WL5. Symptoms and psychiatric distress were similar between normal and abnormal WL5 groups, but the abnormal group had significantly poorer quality of life. Controls and gastroparetics had good correlation of estimated and ingested volumes, but FD did not. Versus FD with normal WL5 capacity, FD with impaired drinking capacity have normal gastric function and similar symptoms but poorer quality of life. FD are less able to predict drinking capacity. These data suggest that WL5 identifies FD with intact gastric function but abnormal visceral perception.
Regulation of oligopeptide transporter (Pept-1) in experimental diabetes
Authors: Gangopadhyay Archana , Thamotharan Manikkavasagar , Adibi Siamak A.
Published: March 2015

The knowledge of expression and biology of the intestinal oligopeptide transporter (Pept-1) in a metabolic disorder such as diabetes may have nutritional and pharmacological implications. To study this problem, rats were made diabetic by streptozotocin injection, and Western and Northern blot analyses and nuclear run-on assay were used to determine the protein and gene expressions of Pept-1 and its rate of transcription, respectively. Uncontrolled diabetes for 96 h increased the activity of Pept-1 in the brush-border membrane of intestinal mucosa. Studies of Michaelis-Menten constant, maximal velocity, and protein expression of Pept-1 indicated that an increase in the abundance of this transporter was responsible for the increased activity. Studies of the gene expression showed that uncontrolled diabetes increased the abundance of mRNA encoding Pept-1 without altering its rate of transcription. Lastly, studies of the specificity of the above effect showed that uncontrolled diabetes similarly affected the protein and gene expressions of Pept-1 located in the kidney. In conclusion, the data show that 1) uncontrolled diabetes has a tropic effect on Pept-1 and 2) the effect is systemic, and its molecular mechanism appears to be an increase in the stabilization of mRNA encoding Pept-1.
Vascular ligation response is independent of p107: stressing the role of the related p130
Authors: Sindermann Jürgen R. , Köbbert Christiane , Bauer Florian , Skaletz-Rorowski Adriane , Hohage Helge , Plenz Gabriele , Breithardt Günter , March Keith L.
Published: March 2015

Recent studies have revealed the role of the pRb family members pRb and p130 in the response to vascular injury. We evaluated the arterial injury response in the absence of p107, a protein that shares a high degree of homology with the injury-controlling p130. Carotid artery ligation and perivascular electric injury of the femoral artery were applied to p107 knockout (p107 –/–) mice, and morphometric analysis was performed 3 wk after ligation and electric injury. Arterial vessels of p107 –/– mice were indistinguishable from controls under basal conditions. After carotid artery ligation the p107 –/– mice ( n = 7) did not display an enhanced ligation response compared with controls ( n = 9), which was studied over a distance of ∼450 μm proximal and ∼200 μm distal from the ligation site, with regard to vessel wall area, neointima area, and lumen area. Corresponding with this, morphometric data obtained from the perivascular electric injury of the femoral artery confirmed the lack of enhanced ligation and injury response in the absence of p107. We conclude that the pRb family member p107 is not a key regulator in vascular injury response. These data, in conjunction with previously reported results, indicate that the control of vascular injury response is not a redundant feature of pRb proteins but primarily specific for p130. Further studies on functional domains of p130 and p107 will help to resolve the pathways in vascular injury response.
The effect of interleukin-6 on L-selectin levels on polymorphonuclear leukocytes
Authors: Suwa Tatsushi , Hogg James C. , Quinlan Kevin B. , van Eeden Stephan F.
Published: March 2015

Interleukin-6 (IL-6) shortens the transit time of polymorphonuclear leukocytes (PMN) through the marrow and accelerates their release into the circulation. In contrast to other inflammatory stimuli, this response is associated with a decrease in L-selectin levels on circulating PMN. The present study was designed to determine the effect of IL-6 on L-selectin levels of PMN in rabbits. Recombinant human IL-6 (2 μg/kg) caused a decrease in L-selectin levels on circulating PMN 3 to 12 h after treatment ( P < 0.05). L-selectin levels decreased on PMN already in the circulation for up to 4 h ( P < 0.05), on PMN released from the marrow posttreatment for up to 12 h ( P < 0.01) and on PMN in the marrow for up to 6 h ( P < 0.05) after IL-6 treatment. We conclude that IL-6 decreases L-selectin levels on circulating PMN by demarginating PMN with low levels of L-selectin and by releasing PMN from the marrow with low levels of L-selectin. We postulate that this prolonged downregulation of L-selectin on circulating PMN could influence their recruitment into inflammatory sites.
Catheterization of pulmonary artery in rats with an ultraminiature catheter pressure transducer
Authors: Deten Alexander , Millar Huntly , Zimmer Heinz-Gerd
Published: March 2015

Utilizing new materials and miniaturization techniques, an ultraminiature catheter pressure transducer for catheterization of the pulmonary artery (PA) has been developed and applied in intact, spontaneously breathing, anesthetized rats. The catheter arrangement consists of three components: 1) an SPR-671 ultraminiature pressure transducer (measuring catheter), 2) a plastic introducer (sheath) that is slipped over the measuring catheter, and 3) an external wire mounted on the outside of the introducer for bending its tip. The measuring catheter is first inserted through the right jugular vein into the right ventricle. The introducer is then slipped over it. The tip of the introducer is bent so that there is an angle of ∼90° or less to the shaft. The measuring catheter is advanced across the pulmonary valve into the PA. Measurements of pulmonary arterial pressure were made in five male Long Evans (364 ± 7 g body wt) and five female Sprague-Dawley (244 ± 7 g body wt) rats under control conditions. The effects of infusion of norepinephrine (0.1 mg·kg–1·h–1 iv for 20-min duration) were tested in Long Evans rats. Pulmonary arterial systolic pressure measurements were 34.0 ± 0.8 and 29.5 ± 0.4 mmHg, and diastolic pressure values were 23.6 ± 0.8 and 18.1 ± 0.6 mmHg in male Long Evans and female Sprague-Dawley rats, respectively. Norepinephrine induced an increase in pulmonary arterial systolic (40.8 ± 0.1 mmHg) and diastolic (28.6 ± 0.4 mmHg) pressures and an elevation in pulmonary vascular resistance from a control value of 0.093 ± 0.003 to 0.103 ± 0.004 mmHg·kg·min·ml–1.
Ventricular remodeling and diastolic myocardial dysfunction in rats submitted to protein-calorie malnutrition
Authors: Fioretto José R. , Querioz Susana S. , Padovani Carlos R. , Matsubara Luiz S. , Okoshi Katashi , Matsubara Beatriz B.
Published: March 2015

The effects of protein-calorie malnutrition (PCM) on heart structure and function are not completely understood. We studied heart morphometric, functional, and biochemical characteristics in undernourished young Wistar rats. They were submitted to PCM from birth (undernourished group, UG). After 10 wk, left ventricle function was studied using a Langendorff preparation. The results were compared with age-matched rats fed ad libitum (control group, CG). The UG rats achieved 47% of the body weight and 44% of the left ventricular weight (LVW) of the CG. LVW-to-ventricular volume ratio was smaller and myocardial hydroxyproline concentration was higher in the UG. Left ventricular systolic function was not affected by the PCM protocol. The myocardial stiffness constant was greater in the UG, whereas the end-diastolic pressure-volume relationship was not altered. In conclusion, the heart is not spared from the adverse effects of PCM. There is a geometric alteration in the left ventricle with preserved ventricular compliance despite the increased passive myocardial stiffness. The systolic function is preserved.
ACh and adenosine activate PI3-kinase in rabbit hearts through transactivation of receptor tyrosine kinases
Authors: Krieg Thomas , Qin Qining , McIntosh Elizabeth C. , Cohen Michael V. , Downey James M.
Published: March 2015

Adenosine and acetylcholine (ACh) trigger preconditioning through different signaling pathways. We tested whether either could activate myocardial phosphatidylinositol 3-kinase (PI3-kinase), a putative signaling protein in ischemic preconditioning. We used phosphorylation of Akt, a downstream target of PI3-kinase, as a reporter. Exposure of isolated rabbit hearts to ACh increased Akt phosphorylation 2.62 ± 0.33 fold ( P = 0.001), whereas adenosine caused a significantly smaller increase (1.52 ± 0.08 fold). ACh-induced activation of Akt was abolished by the tyrosine kinase blocker genistein indicating at least one tyrosine kinase between the muscarinic receptor and Akt. ACh-induced Akt activation was blocked by the Src tyrosine kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-( t-butyl)pyrazolo[3,4- d]pyrimidine (PP2) and by 4-(3-chloroanilino)-6,7-dimethoxyquinazoline (AG-1478), an epidermal growth factor receptor (EGFR) inhibitor, suggesting phosphorylation of a receptor tyrosine kinase in an Src tyrosine kinase-dependent manner. ACh caused tyrosine phosphorylation of the EGFR, which could be blocked by PP2, thus supporting this receptor hypothesis. AG-1478 failed to block the cardioprotection of ACh, however, suggesting that other receptor tyrosine kinases might be involved. Therefore, Giprotein-coupled receptors can activate PI3-kinase/Akt through transactivation of receptor tyrosine kinases in an Src tyrosine kinase-dependent manner.
Cathepsin B deficiency attenuates cardiac remodeling in response to pressure overload via TNF-α/ASK1/JNK pathway
Authors: Wu Qing-Qing , Xu Man , Yuan Yuan , Li Fang-Fang , Yang Zheng , Liu Yuan , Zhou Meng-Qiao , Bian Zhou-Yan , Deng Wei , Gao Lu , Li Hongliang , Tang Qi-Zhu
Published: February 2015

Cathepsin B (CTSB), a member of the lysosomal cathepsin family that is expressed in both murine and human hearts, was previously shown to participate in apoptosis, autophagy, and the progression of certain types of cancers. Recently, CTSB has been linked to myocardial infarction. Given that cathepsin L, another member of the lysosomal cathepsin family, ameliorates pathological cardiac hypertrophy, we hypothesized that CTSB plays a role in pressure overload-induced cardiac remodeling. Here we report that CTSB was upregulated in cardiomyocytes in response to hypertrophic stimuli both in vivo and in vitro. Moreover, knockout of CTSB attenuated pressure overload-induced cardiac hypertrophy, fibrosis, dysfunction, and apoptosis. Furthermore, the aortic banding-induced activation of TNF-α, apoptosis signal-regulating kinase 1 (ASK1), c-Jun NH2-terminal kinases (JNK), c-Jun, and release of cytochrome c was blunted by CTSB deficiency, which was further confirmed in in vitro studies induced by angiotensin II. In cardiomyocytes pretreatment with SP600125, a JNK inhibitor, suppressed the cardiomyocytes hypertrophy by inhibiting the ASK1/JNK pathway. Altogether, these data indicate that the CTSB protein functions as a necessary modulator of hypertrophic response by regulating TNF-α/ASK1/JNK signaling pathway involved in cardiac remodeling.
Overexpression of alcohol dehydrogenase exacerbates ethanol-induced contractile defect in cardiac myocytes
Authors: Duan Jinhong , McFadden Grant E. , Borgerding Anthony J. , Norby Faye L. , Ren Bonnie H. , Ye Gang , Epstein Paul N. , Ren Jun
Published: March 2015

Alcoholic cardiomyopathy is characterized by impaired ventricular function although its toxic mechanism is unclear. This study examined the impact of cardiac overexpression of alcohol dehydrogenase (ADH), which oxidizes ethanol into acetaldehyde (ACA), on ethanol-induced cardiac contractile defect. Mechanical and intracellular Ca2+properties were evaluated in ventricular myocytes from ADH transgenic and wild-type (FVB) mice. ACA production was assessed by gas chromatography. ADH myocytes exhibited similar mechanical properties but a higher efficiency to convert ACA compared with FVB myocytes. Acute exposure to ethanol depressed cell shortening and intracellular Ca2+ in the FVB group with maximal inhibitions of 23.3% and 23.4%, respectively. Strikingly, the ethanol-induced depression on cell shortening and intracellular Ca2+ was significantly augmented in the ADH group, with maximal inhibitions of 43.7% and 40.6%, respectively. Pretreatment with the ADH inhibitor 4-methylpyrazole (4-MP) or the aldehyde dehydrogenase inhibitor cyanamide prevented or augmented the ethanol-induced inhibition, respectively, in the ADH but not the FVB group. The ADH transgene also substantiated the ethanol-induced inhibition of maximal velocity of shortening/relengthening and unmasked an ethanol-induced prolongation of the duration of shortening/relengthening, which was abolished by 4-MP. These data suggest that elevated cardiac ACA exposure due to enhanced ADH expression may play an important role in the development of alcoholic cardiomyopathy.
Role of FKBP12.6 in cADPR-induced activation of reconstituted ryanodine receptors from arterial smooth muscle
Authors: Tang Wang-Xian , Chen Ya-Fei , Zou Ai-Ping , Campbell William B. , Li Pin-Lan
Published: March 2015

cADP ribose (cADPR) serves as second messenger to activate the ryanodine receptors (RyRs) of the sarcoplasmic reticulum (SR) and mobilize intracellular Ca2+in vascular smooth muscle cells. However, the mechanisms mediating the effect of cADPR remain unknown. The present study was designed to determine whether FK-506 binding protein 12.6 (FKBP12.6), an accessory protein of the RyRs, plays a role in cADPR-induced activation of the RyRs. A 12.6-kDa protein was detected in bovine coronary arterial smooth muscle (BCASM) and cultured CASM cells by being immunoblotted with an antibody against FKBP12, which also reacted with FKBP12.6. With the use of planar lipid bilayer clamping techniques, FK-506 (0.01–10 μM) significantly increased the open probability ( NPO) of reconstituted RyR/Ca2+release channels from the SR of CASM. This FK-506-induced activation of RyR/Ca2+release channels was abolished by pretreatment with anti-FKBP12 antibody. The RyRs activator cADPR (0.1–10 μM) markedly increased the activity of RyR/Ca2+release channels. In the presence of FK-506, cADPR did not further increase the NPOof RyR/Ca2+release channels. Addition of anti-FKBP12 antibody also completely blocked cADPR-induced activation of these channels, and removal of FKBP12.6 by preincubation with FK-506 and subsequent gradient centrifugation abolished cADPR-induced increase in the NPOof RyR/Ca2+release channels. We conclude that FKBP12.6 plays a critical role in mediating cADPR-induced activation of RyR/Ca2+release channels from the SR of BCASM.
CO2-dependent components of sinus arrhythmia from the start of breath holding in humans
Authors: Cooper H. E. , Parkes M. J. , Clutton-Brock T. H.
Published: March 2015

A substantial portion of sinus arrhythmia in conscious humans appears to be caused by the CO2-dependent central respiratory rhythm. Under some circumstances, therefore, sinus arrhythmia might indicate the presence of the central respiratory rhythm. Humans can voluntarily modify their central respiratory rhythm (e.g., by pacing breathing or by delaying or advancing breaths), but it is not clear what happens to it from the start of breath holding. In this study, we show that sinus arrhythmia persists from the start of breath holds prolonged by preoxygenation. We also show that some of the frequency components of sinus arrhythmia start within each subject's eupneic frequency range and change when end-tidal Pco2is lowered or raised, as we would expect if the central respiratory rhythm continues from the start of breath holding. We discuss whether sinus arrhythmia can indicate if the central respiratory rhythm continues from the start of breath holding.
Estradiol improves right ventricular function in rats with severe angioproliferative pulmonary hypertension: effects of endogenous and exogenous sex hormones
Authors: Frump Andrea L. , Goss Kara N. , Vayl Alexandra , Albrecht Marjorie , Fisher Amanda , Tursunova Roziya , Fierst John , Whitson Jordan , Cucci Anthony R. , Brown M. Beth , Lahm Tim
Published: February 2015

Estrogens are disease modifiers in PAH. Even though female patients exhibit better right ventricular (RV) function than men, estrogen effects on RV function (a major determinant of survival in PAH) are incompletely characterized. We sought to determine whether sex differences exist in RV function in the SuHx model of PAH, whether hormone depletion in females worsens RV function, and whether E2 repletion improves RV adaptation. Furthermore, we studied the contribution of ERs in mediating E2’s RV effects. SuHx-induced pulmonary hypertension (SuHx-PH) was induced in male and female Sprague-Dawley rats as well as OVX females with or without concomitant E2 repletion (75 μg·kg−1·day−1). Female SuHx rats exhibited superior CI than SuHx males. OVX worsened SuHx-induced decreases in CI and SuHx-induced increases in RVH and inflammation (MCP-1 and IL-6). E2 repletion in OVX rats attenuated SuHx-induced increases in RV systolic pressure (RVSP), RVH, and pulmonary artery remodeling and improved CI and exercise capacity (V̇o2max). Furthermore, E2 repletion ameliorated SuHx-induced alterations in RV glutathione activation, proapoptotic signaling, cytoplasmic glycolysis, and proinflammatory cytokine expression. Expression of ERα in RV was decreased in SuHx-OVX but was restored upon E2 repletion. RV ERα expression was inversely correlated with RVSP and RVH and positively correlated with CO and apelin RNA levels. RV-protective E2 effects observed in females were recapitulated in male SuHx rats treated with E2 or with pharmacological ERα or ERβ agonists. Our data suggest significant RV-protective ER-mediated effects of E2 in a model of severe PH.
Heparin-binding EGF-like growth factor regulates elastin and FGF-2 expression in pulmonary fibroblasts
Authors: Liu Jianghuai , Rich Celeste B. , Buczek-Thomas Jo Ann , Nugent Matthew A. , Panchenko Mikhail P. , Foster Judith Ann
Published: March 2015

Elastase degradation of elastin within alveolar walls is an important event in the development of pulmonary emphysema. In addition to elastolytic activities, elastases release growth factors from extracellular matrices and interstitial cell surfaces that can regulate elastogenesis and other cellular responses. In the present study, we demonstrate that brief treatment of matrix-laden rat pulmonary fibroblast cultures with pancreatic elastase results in the release of soluble heparin-binding epidermal growth factor-like growth factor (HB-EGF) concomitant with a decrease in HB-EGF binding to both heparan sulfate proteoglycan and receptor sites on the cells. In undigested, matrix-laden fibroblasts, HB-EGF significantly downregulates elastin mRNA via activation of epidermal growth factor receptor. Results from nuclear run-on analyses show that HB-EGF downregulates elastin mRNA via transcriptional suppression. HBEGF treatment stimulates MAP or ERK kinase (MEK)-dependent ERK1/2 phosphorylation and leads to nuclear accumulation of Fra-1. Blocking ERK1/2 activation by MEK1/2 inhibitors (PD-98059 or U-0126) diminishes HB-EGF-induced Fra-1 accumulation and subsequent downregulation of elastin mRNA. Coaddition of two elastase-released growth factors, HB-EGF and FGF-2, results in an additive inhibitory effect on elastin mRNA levels. Furthermore, HB-EGF addition to pulmonary fibroblasts increases FGF-2 mRNA and protein levels. These data suggest that HB-EGF and FGF-2 act in concert to regulate the synthesis of elastin in injury/repair situations.
Adenoviral E1A modulates inflammatory mediator expression by lung epithelial cells exposed to PM10
Authors: Fujii Takeshi , Hogg James C. , Keicho Naoto , Vincent Renaud , Van Eeden Stephan F. , Hayashi Shizu
Published: March 2015

We examined the hypothesis that ambient particulate matter with a diameter of <10 μm (PM10)-induced lung inflammation is amplified by latent adenovirus infection. Inflammatory mediator expression in response to PM10exposure was compared between adenovirus E1A-transfected A549 alveolar epithelial cells and cells transfected with control plasmid. Messenger RNA was measured by the RNase protection assay and protein by ELISA or immunocytochemistry. Intercellular adhesion molecule-1 and IL-8 mRNA and protein were increased in E1A-positive cells exposed to 500 μg/ml PM10. Monocyte chemoattractant protein-1 mRNA and protein were unchanged in E1A-positive cells but increased in E1A-negative cells after 100 and 500 μg/ml PM10exposure. Electrophoretic mobility shift assays showed increased NF-κB and decreased specificity protein 1 nuclear binding in E1A-positive cells exposed to PM10. These results indicate that E1A modulates cytokine and adhesion molecule expression in epithelial cells in a manner that could amplify PM10-induced lung inflammation. We suggest that this amplified inflammatory response may contribute to the pathogenesis of exacerbations of chronic obstructive pulmonary disease associated with exposure to particulate matter air pollution.