bluuebunny/crossref_metadata_2025 huggingface dataset:
ON FOX QUOTIENTS OF ARBITRARY GROUP ALGEBRAS
Authors: HARTL MANFRED
Published: September 2010

Certain subquotients of group algebras are determined as a basis for subsequent computations of relative Fox and dimension subgroups. More precisely, for a group G and N-series [Formula: see text] of G let [Formula: see text], n ≥ 0, denote the filtration of the group algebra R(G) induced by [Formula: see text], and IR(G) its augmentation ideal. For subgroups H of G, left ideals J of R(H) and right H-submodules M of [Formula: see text] the quotients IR(G)J/MJ are studied by homological methods, notably for M = IR(G)IR(H), IR(H)IR(G) + I([H, G])R(G) and [Formula: see text] for a normal subgroup N in G; in the latter case the module IR(G)J/MJ is completely determined for n = 2. The groups [Formula: see text] are studied and explicitly computed for n ≤ 3 in terms of enveloping rings of certain graded Lie rings and of torsion products of abelian groups.
KAZHDAN CONSTANTS OF GROUP EXTENSIONS
Authors: HADAD UZY
Published: September 2010

We give bounds on Kazhdan constants of abelian extensions of (finite) groups. As a corollary, we improved known results of Kazhdan constants for some meta-abelian groups and for the relatively free group in the variety of p-groups of lower p-series of class 2. Furthermore, we calculate Kazhdan constants of the tame automorphism groups of the free nilpotent groups.
CONFORMAL COSMOLOGICAL MODEL PARAMETERS WITH DISTANT SNe Ia DATA: "GOLD" AND "SILVER"
Authors: ZAKHAROV ALEXANDER F. , PERVUSHIN VICTOR N.
Published: September 2010

We assume that Type Ia supernovae (SNe Ia) are standard candles which one could use to test cosmological theories. The Hubble Space Telescope team analyzed 186 SNe Ia1 to test the standard cosmological model (SC) associated with expanded lengths in the universe and evaluate its parameters. We use the same sample to determine parameters of the conformal cosmological model (CC) with relative reference units of intervals, so that conformal quantities of general relativity are interpreted as observables. We concluded, that the test is extremely useful and allows the evaluation of the parameters of the model. From a formal statistical point of view the best-fit of the CC model is almost the same quality approximation as the best-fit of the SC model with ΩΛ = 0.72, Ωm = 0.28. As it was noted earlier, for CC models, a rigid matter component could substitute the Λ-term (or quintessence) existing in the SC model. We note that a free massless scalar field can generate such a rigid matter. We describe the results of our analysis for more recent "gold" data (for 192 SNe Ia).
AVERAGING GEOMETRICAL OBJECTS ON A DIFFERENTIABLE MANIFOLD
Authors: BRANNLUND JOHAN , VAN DEN HOOGEN ROBERT , COLEY ALAN
Published: September 2010

We construct a framework within which a mathematically precise, fully covariant, and exact averaging procedure for tensor fields on a manifold can be formulated. In particular, we introduce the Weitzenböck connection for parallel transport and argue that, within the context of averaging, frames and connections are the natural geometrical objects on the manifold.
SCALE INVARIANCE FROM MODIFIED DISPERSION RELATIONS
Authors: LU YAO , PIAO YUN-SONG
Published: September 2010

In this paper, inspired by the investigations on the theory of cosmological perturbations in Hořava–Lifshitz cosmology, we calculate the spectrum of primordial perturbation lead by a modified dispersion relation in proper time ω pro ~ kz/ap in power-law expansion/contraction background a ~ tn · z is the critical exponent and p is not necessarily equal to z · p = z is well-motivated by Hořava–Lifshitz gravity, and the cases with p ≠ z are generalizations beyond the scope. We discuss that for fixed z, if the spectrum is required to be scale-invariant, how should p depend on n. We conclude that there is always room for parameters for the generation of scale-invariant spectrum.
EXACT AND QUASI-EXACT MODELS OF STRANGE STARS
Authors: DE AVELLAR MARCIO G. B. , HORVATH J. E.
Published: September 2010

We construct and compare in this work a variety of simple models for strange stars, namely, hypothetical self-bound objects made of a cold stable version of the quark-gluon plasma. Exact, quasi-exact and numerical models are examined to find the most economical description for these objects. A simple and successful parametrization of them is given in terms of the central density, and the differences among the models are explicitly shown and discussed. In particular, we present a model starting with a Gaussian ansatz for the density profile that provides a very accurate and almost complete analytical integration of the problem, modulo a small difference for one of the metric potentials.
THE GRAVITATIONAL ENERGY PROBLEM FOR COSMOLOGICAL MODELS IN TELEPARALLEL GRAVITY
Authors: ULHOA S. C. , DA ROCHA NETO J. F. , MALUF J. W.
Published: September 2010

We present a method to calculate the gravitational energy when asymptotic boundary conditions for the space–time are not given. This is the situation for most of the cosmological models. The expression for the gravitational energy is obtained in the context of the teleparallel equivalent of general relativity. We apply our method first to the Schwarzschild–de Sitter solution of Einstein's equation, and then to the Robertson–Walker universe. We show that in the first case our method leads to an average energy density of the vacuum space–time, and in the latter case the energy vanishes in the case of null curvature.
EFFECTS OF ELECTROMAGNETIC FIELD ON THE DYNAMICS OF BIANCHI TYPE VI0UNIVERSE WITH ANISOTROPIC DARK ENERGY
Authors: SHARIF M. , ZUBAIR M.
Published: September 2010

Spatially homogeneous and anisotropic Bianchi type VI0cosmological models with cosmological constant are investigated in the presence of anisotropic dark energy. We examine the effects of electromagnetic field on the dynamics of the universe and anisotropic behavior of dark energy. The law of variation of the mean Hubble parameter is used to find exact solutions of the Einstein field equations. We find that electromagnetic field promotes anisotropic behavior of dark energy which becomes isotropic for future evolution. It is concluded that the isotropic behavior of the universe model is seen even in the presence of electromagnetic field and anisotropic fluid.
ON THE TIME TIMES TEMPERATURE BOUND
Authors: LÓPEZ-ORTEGA A.
Published: September 2010

Recently Hod proposed a lower bound on the relaxation time of a perturbed thermodynamic system. For gravitational systems this bound transforms into a condition on the fundamental quasinormal frequency. We test the bound in some space–times whose quasinormal frequencies are calculated exactly, as the three-dimensional BTZ black hole, the D-dimensional de Sitter space–time, and the D-dimensional Nariai space–time. We find that for some of these space–times their fundamental quasinormal frequencies do not satisfy the bound proposed by Hod.
COMPOUND ANALYSIS VIA GRAPH KERNELS INCORPORATING CHIRALITY
Authors: BROWN J.B. , URATA TAKASHI , TAMURA TAKEYUKI , ARAI MIDORI A. , KAWABATA TAKEO , AKUTSU TATSUYA
Published: September 2010

High accuracy is paramount when predicting biochemical characteristics using Quantitative Structural-Property Relationships (QSPRs). Although existing graph-theoretic kernel methods combined with machine learning techniques are efficient for QSPR model construction, they cannot distinguish topologically identical chiral compounds which often exhibit different biological characteristics. In this paper, we propose a new method that extends the recently developed tree pattern graph kernel to accommodate stereoisomers. We show that Support Vector Regression (SVR) with a chiral graph kernel is useful for target property prediction by demonstrating its application to a set of human vitamin D receptor ligands currently under consideration for their potential anti-cancer effects.
STEPWISE ORIGIN AND FUNCTIONAL DIVERSIFICATION OF THE AFL SUBFAMILY B3 GENES DURING LAND PLANT EVOLUTION
Authors: LI YANG , JIN KE , ZHU ZHU , YANG JI
Published: September 2010

The AFL genes (ABI3/VP1, FUS3 and LEC2) belong to the plant-specific B3 superfamily, playing important roles in regulating seed development and maturation. It is unclear, however, whether these genes appeared at the same time as the origin of seed plants and if all these genes are necessary and sufficient for seed development for all seed plants. By conducting a genome-wide comparative analysis of the putative AFL genes in various plant species, we found that the ABI3 homologous genes existed in all land plant genomes, but the FUS3 homologous were present only in seed plant genomes and the LEC2-like sequences only in dicot genomes. Phylogenetic analysis indicated that the AFL genes had undergone successive rounds of gene duplication and subsequent diversification during land plant evolution, resulting in the stepwise origin of the ABI3, FUS3 and LEC2 genes. Comparison of gene structure of the AFL genes revealed a trend of decreasing in the number of conserved domains from ABI3 to FUS3 and LEC2.
CANCER CLASSIFICATION FROM THE GENE EXPRESSION PROFILES BY DISCRIMINANT KERNEL-PLS
Authors: TANG KAI-LIN , YAO WEI-JIA , LI TONG-HUA , LI YI-XUE , CAO ZHI-WEI
Published: September 2010

Cancer diagnosis depending on microarray technology has drawn more and more attention in the past few years. Accurate and fast diagnosis results make gene expression profiling produced from microarray widely used by a large range of researchers. Much research work highlights the importance of gene selection and gains good results. However, the minimum sets of genes derived from different methods are seldom overlapping and often inconsistent even for the same set of data, partially because of the complexity of cancer disease. In this paper, cancer classification was attempted in an alternative way of the whole gene expression profile for all samples instead of partial gene sets. Here, the three common sets of data were tested by NIPALS-KPLS method for acute leukemia, prostate cancer and lung cancer respectively. Compared to other conventional methods, the results showed wide improvement in classification accuracy. This paper indicates that sample profile of gene expression may be explored as a better indicator for cancer classification, which deserves further investigation.
CIRCUIT DESIGN FOR A MEASUREMENT-BASED QUANTUM CARRY-LOOKAHEAD ADDER
Authors: TRISETYARSO AGUNG , VAN METER RODNEY
Published: September 2010

We present the design and evaluation of a quantum carry-lookahead adder (QCLA) using measurement-based quantum computation (MBQC), called MBQCLA. QCLA was originally designed for an abstract, concurrent architecture supporting long-distance communication, but most realistic architectures heavily constrain communication distances. The quantum carry-lookahead adder is faster than a quantum ripple-carry adder; QCLA has logarithmic depth while ripple adders have linear depth. MBQCLA utilizes MBQC's ability to transfer quantum states in unit time to accelerate addition. MBQCLA breaks the latency limit of addition circuits in nearest neighbor-only architectures: compared to the Θ(n) limit on circuit depth for linear nearest-neighbor architectures, it can reach Θ(log n) depth. MBQCLA is an order of magnitude faster than a ripple-carry adder when adding registers longer than 100 qubits, but requires a cluster state that is an order of magnitude larger. The cluster state resources can be classified as computation and communication; for the unoptimized form, ≈ 88% of the resources are used for communication. Hand optimization of horizontal communication costs results in a ≈ 12% reduction in spatial resources for the in-place MBQCLA circuit. For comparison, a graph state quantum carry-lookahead adder (GSQCLA) uses only ≈ 9% of the spatial resources of the MBQCLA.
RELATIVE ENTROPY OF ENTANGLEMENT FOR TWO-QUBIT STATE WITH z-DIRECTIONAL BLOCH VECTORS
Authors: PARK DAEKIL
Published: September 2010

So far there is no closed formula for relative entropy of entanglement of arbitrary two-qubit states. In this paper we present a method, which guarantees the derivation of the relative entropy of entanglement for most states that have z-directional Bloch vectors. It is shown that the closest separable states for those states also have z-directional Bloch vectors though there are few exceptions.
ON VALUES OF d(n!)/m!, ϕ(n!)/m! AND σ(n!)/m!
Authors: BACZKOWSKI DANIEL , FILASETA MICHAEL , LUCA FLORIAN , TRIFONOV OGNIAN
Published: September 2010

For f one of the classical arithmetic functions d, ϕ and σ, we establish constraints on the quadruples (n, m, a, b) of integers satisfying f(n!)/m! = a/b. In particular, our results imply that as nm tends to infinity, the number of distinct prime divisors dividing the product of the numerator and denominator of the fraction f(n!)/m!, when reduced, tends to infinity.
GENERATORS OF ARITHMETIC QUATERNION GROUPS AND A DIOPHANTINE PROBLEM
Authors: JAHANGIRI MAJID
Published: September 2010

Let p be a prime and a a quadratic non-residue ( mod p). Then the set of integral solutions of the Diophantine equation [Formula: see text] form a cocompact discrete subgroup Γp, a ⊂ SL(2, ℝ) which is commensurable with the group of units of an order in a quaternion algebra over ℚ. The problem addressed in this paper is an estimate for the traces of a set of generators for Γp, a. Empirical results summarized in several tables show that the trace has significant and irregular fluctuations which is reminiscent of the behavior of the size of a generator for the solutions of Pell's equation. The geometry and arithmetic of the group of units of an order in a quaternion algebra play a key role in the development of the code for the purpose of this paper.
DNA-LINKED PROTEIN ARRAY FOR HIGH-THROUGHPUT PROTEOMICS: FROM SPATIALLY UNKNOWN DNA ARRAYS TO IDENTIFIABLE PROTEIN ARRAYS
Authors: BIYANI MANISH , NEMOTO NAOTO , ICHIKI TAKANORI
Published: September 2010

Protein array technology has a tremendous potential in large-scale and high-throughput functional proteomics. The conventional protein array approach, which is based on one-to-one indexing between a known protein and an array position, is however, not applicable for decoding genetic information from unknown expressed protein arrays and thus less practicable for global proteome analysis. To address this issue, we have introduced a novel concept of DNA-linked protein array by adopting a strategy of one-to-one indexing between spatially unknown individual DNA arrays and their encoded protein array products. A set of test DNA arrays of DNA-binding (POU) domain protein, c-Myc-tagged POU domain protein, and green fluorescent protein were randomly patterned on a glass surface and subsequently converted into identifiable protein arrays by simultaneously producing and linking the encoded proteins to their encoding genes using a puromycin-assisted mRNA–protein fusion approach in situ. For concept validation, functional assay was performed by the screening of mRNA–protein fusion arrays against a mixture of anti-cMyc and anti-GFP antibodies. Moreover, this approach also provides an additional advantage to incorporate post-translational modifications into protein arrays. The concept developed here is expected to markedly enhance the application of protein microarrays to the study of functional proteomics.
ANTIMICROBIAL TESTING, MORPHOLOGICAL CHARACTERIZATION, AND SURFACE POTENTIAL MAPPING OF SILVER-POLY-(METHYL METHACRYLATE) NANOCOMPOSITE FILMS MADE THROUGH MATRIX-ASSISTED PULSED LASER DEPOSITION AGAINST S. AUREUS
Authors: KHAN MISHAE , GITTARD SHAUN D. , NARAYAN ROGER J. , BUBB DANIEL M
Published: September 2010

Silver-poly(methyl methacrylate) nanocomposite thin films were deposited on silicon substrates by means of matrix-assisted pulsed laser deposition. Atomic force microscopy revealed that the surface morphologies of the silver-poly(methyl methacrylate) nanocomposite thin films were dependent on the matrix-assisted pulsed laser evaporation processing parameters. Films produced using 4% (by weight of solvent) silver nanoparticles exhibited the highest antimicrobial activity. Antimicrobial activity of the thin films was dependent on the silver concentration, the microenvironment created by the polymer–silver interaction, and the surface potential.
A COMBINED COMPUTATIONAL/EXPERIMENTAL STUDY OF FLUORESCENT GOLD NANOCLUSTER COMPLEXES
Authors: AN WEI , WINTZINGER LAUREN , TURNER C. HEATH , BAO YUPING
Published: September 2010

We present a combined computational/experimental study of fluorescent Au nanocluster complexes synthesized using small biological molecules. Using density-functional theory, we calculated the binding energy, HOMO–LUMO gap, charge transfer, and bond length of the ligand– Au nanocluster systems. These calculations suggest the formation of ligand–Au nanocluster complexes. We further simulated the HOMO/LUMO states and the absorption spectra of the complexes. The HOMO and LUMO states of the complexes were confined within the Au nanoclusters, suggesting little ligand intrinsic fluorescence. The simulated absorption spectra agreed reasonably well with the experimental data. The simulation results of different systems demonstrate the strong ligand effects on the fluorescent emissions of ligand– Au nanocluster complexes. Our studies provide valuable information for the rational design of next-generation fluorescent tags.
LIPID–POLYMER HYBRID NANOPARTICLES: SYNTHESIS, CHARACTERIZATION AND APPLICATIONS
Authors: ZHANG LI , ZHANG LIANGFANG
Published: September 2010

Nanotechnology has been extensively explored in the past decade to develop a myriad of functional nanostructures to facilitate the delivery of therapeutic and imaging agents for various medical applications. Liposomes and polymeric nanoparticles represent two primary delivery vehicles that are currently under investigation. While many advantages of these two particle platforms have been disclosed, some intrinsic limitations remain to limit their applications at certain extent. Recently, a new type of nanoparticle platform, named lipid–polymer hybrid nanoparticle, has been developed that combines the positive attributes of both liposomes and polymeric nanoparticles while excluding some of their shortages. This new nanoparticle consists of a hydrophobic polymeric core, a lipid shell surrounding the polymeric core, and a hydrophilic polymer stealth layer outside the lipid shell. In this review, we first introduce the synthesis and surface functionalization techniques of the lipid–polymer hybrid nanoparticle, followed by a review of typical characterization of the particles. We then summarize the current and potential medical applications of this new nanoparticle as a delivery vehicle of therapeutic and imaging agents. Finally we highlight some challenges faced in further developing this robust delivery platform.
Connexin 43 hemichannels mediate the Ca2+ influx induced by extracellular alkalinization
Authors: Schalper Kurt A. , Sánchez Helmuth A. , Lee Sung C. , Altenberg Guillermo A. , Nathanson Michael H. , Sáez Juan C.
Published: September 2010

Although alkaline pH is known to trigger Ca2+ influx in diverse cells, no pH-sensitive Ca2+ channel has been identified. Here, we report that extracellular alkalinization induces opening of connexin 43 hemichannels (Cx43 HCs). Increasing extracellular pH from 7.4 to 8.5, in the presence of physiological Ca2+/Mg2+ concentrations, rapidly increased the ethidium uptake rate and open probability of HCs in Cx43 and Cx43EGFP HeLa transfectants (HeLa-Cx3 and HeLa-Cx43EGFP, respectively) but not in parental HeLa cells (HeLa-parental) lacking Cx43 HCs. The increase in ethidium uptake induced by pH 8.5 was not affected by raising the extracellular Ca2+ concentration from 1.8 to 10 mM but was inhibited by a connexin HC inhibitor (La3+). Probenecid, a pannexin HC blocker, had no effect. Extracellular alkalinization increased the intracellular Ca2+ levels only in cells expressing HCs. The above changes induced by extracellular alkalinization did not change the cellular distribution of Cx43, suggesting that HC activation occurs through a gating mechanism. Experiments on cells expressing a COOH-terminal truncated Cx43 mutant indicated that the effects of alkalinization on intracellular Ca2+ and ethidium uptake did not depend on the Cx43 C terminus. Moreover, purified dephosphorylated Cx43 HCs reconstituted in liposomes were Ca2+ permeable, suggesting that Ca2+ influx through Cx43 HCs could account for the elevation in intracellular Ca2+ elicited by extracellular alkalinization. These studies identify a membrane pathway for Ca2+ influx and provide a potential explanation for the activation of cellular events induced by extracellular alkalinization.
Role of calcium-phosphate deposition in vascular smooth muscle cell calcification
Authors: Villa-Bellosta Ricardo , Millan Angel , Sorribas Víctor
Published: September 2010

In this work we are studying whether calcium phosphate deposition (CPD) during vascular calcification is a passive or a cell-mediated mechanism. Passive CPD was studied in fixed vascular smooth muscle cells (VSMC), which calcify faster than live cells in the presence of 1.8 mM Ca2+ and 2 mM Pi. CPD seems to be a cell-independent process that depends on the concentration of calcium, phosphate, and hydroxyl ions, but not on Ca × Pi concentration products, given that deposition is obtained with 2 × 2 and 4 × 1 Ca × Pi mM2 but not with 2 × 1 or 1 × 4 Ca × Pi mM2. Incubation with 4 mM Pi without CPD (i.e., plus 1 mM Ca) does not induce osteogene expression. Increased expression of bone markers such as Bmp2 and Cbfa1 is only observed concomitantly with CPD. Hydroxyapatite is the only crystalline phase in both lysed and live cells. Lysed cell deposits are highly crystalline, whereas live cell deposits still contain large amounts of amorphous calcium. High-resolution transmission electron microscopy revealed a nanostructure of rounded crystallites of 5–10 nm oriented at random in lysed cells, which is compatible with spontaneous precipitation. The nanostructure in live cells consisted of long fiber crystals, 10-nm thick, embedded in an amorphous matrix. This structure indicates an active role of cells in the process of hydroxyapatite crystallization. In conclusion, our data suggest that CPD is a passive phenomenon, which triggers the osteogenic changes that are involved in the formation of a well organized, calcified crystalline structure.
Glutamine protects against apoptosis via downregulation of Sp3 in intestinal epithelial cells
Authors: Ban Kechen , Kozar Rosemary A.
Published: September 2010

Glutamine plays a key role in intestinal growth and maintenance of gut function, and as we have shown protects the postischemic gut (Kozar RA, Scultz SG, Bick RJ, Poindexter BJ, Desoigne R, Weisbrodt NW, Haber MM, Moore FA. Shock 21: 433–437, 2004). However, the precise mechanisms of the gut protective effects of glutamine have not been well elucidated. In the present study, RNA microarray was performed to obtain differentially expressed genes in intestinal epithelial IEC-6 cells following either 2 mM or 10 mM glutamine. The result demonstrated that specificity protein 3 (Sp3) mRNA expression was downregulated 3.1-fold. PCR and Western blot confirmed that Sp3 expression was decreased by glutamine in a time- and dose-dependent fashion. To investigate the role of Sp3, Sp3 gene siRNA silencing was performed and apoptosis was assessed. Silencing of Sp3 demonstrated a significant increase in Bcl-2 and decrease in Bax protein expression, as well as a decrease in caspase-3, -8, and -9 protein expression and activity. The protein expression of apoptosis-related proteins after hypoxia/reoxygenation was similar to that of normoxia and correlated with a decrease in DNA fragmentation. Importantly, the addition of glutamine to Sp3-silenced cells did not further lessen apoptosis, suggesting that Sp3 plays a major role in the inhibitory effect of glutamine on apoptosis. This novel finding may explain in part the gut-protective effects of glutamine.
ID family protein expression and regulation in hypoxic pulmonary hypertension
Authors: Lowery Jonathan W. , Frump Andrea L. , Anderson Lynda , DiCarlo Gabriella E. , Jones Mark T. , de Caestecker Mark P.
Published: September 2010

Bone morphogenetic protein (BMP) signaling has been linked to the development of pulmonary hypertension (PH). Inhibitors of differentiation (ID) proteins (ID1–4) are a family of basic helix-loop-helix transcription factors that are downstream targets of the BMP signaling pathway, but the role that ID proteins play in the development of PH is unknown. To address this, we evaluated pulmonary expression of ID proteins in a mouse model of hypoxia-induced PH. There is selective induction of ID1 and ID3 expression in hypoxic pulmonary vascular smooth muscle cells (VSMCs) in vivo, and ID1 and ID3 expression are increased by hypoxia in cultured pulmonary VSMCs in a BMP-dependent fashion. ID4 protein is barely detectable in the mouse lung, and while ID2 is induced in hypoxic peripheral VSMCs in vivo, it is not increased by hypoxia or BMP signaling in cultured pulmonary VSMCs. In addition, the PH response to chronic hypoxia is indistinguishable between wild type and Id1 null mice. This is associated with a compensatory increase in ID3 but not ID2 expression in pulmonary VSMCs of Id1 null mice. These findings indicate that ID1 is dispensable for mounting a normal pulmonary vascular response to hypoxia, but suggest that ID3 may compensate for loss of ID1 expression in pulmonary VSMCs. Taken together, these findings indicate that ID1 and ID3 expression are regulated in a BMP-dependent fashion in hypoxic pulmonary VSMCs, and that ID1 and ID3 may play a cooperative role in regulating BMP-dependent VSMC responses to chronic hypoxia.
β-Catenin is markedly induced in a murine model of an arteriovenous fistula: the effect of metalloproteinase inhibition
Authors: Nath Karl A. , Grande Joseph P. , Kang Lu , Juncos Julio P. , Ackerman Allan W. , Croatt Anthony J. , Katusic Zvonimir S.
Published: September 2010

Neointimal hyperplasia contributes to failure of hemodialysis arteriovenous fistulas (AVFs). Increased expression of matrix metalloproteinase (MMP)-9 occurs in AVFs, and MMP-9 is implicated in neointimal hyperplasia and vascular injury. Recent studies demonstrate that MMP-9, by degrading N-cadherin, leads to increased expression of β-catenin and β-catenin-dependent proliferation of smooth muscle cells. The present study examined this pathway in the venous limb of a murine AVF model. Western analyses demonstrate that, in this model, there is diminished expression of N-cadherin accompanied by increased expression of β-catenin, c-Myc, and proliferating cell nuclear antigen (PCNA). By immunohistochemistry, β-catenin and c-Myc localized to proliferating smooth muscle cells in the venous limb of the AVF. Increased expression of β-catenin was accompanied by augmented expression of phosphorylated (p)-glycogen synthase kinase (GSK)-3β, GSK-3β, and integrin-linked kinase. The administration of doxycycline suppressed MMP-9 expression but did not reduce venous histological injury in the AVF, or increase AVF patency assessed 6 wk after its creation. Doxycycline did not influence expression of β-catenin, c-Myc, GSK-3β, or integrin-linked kinase. Thus, in this vascular injury model, the upregulation of β-catenin cannot be readily attributed to MMP-9 upregulation; increased β-catenin expression may reflect either the upregulation of p-GSK-3β, GSK-3β, or integrin-linked kinase. This study provides the first exploration of β-catenin in an AVF, demonstrating substantial upregulation of this mitogenic signaling molecule and uncovering possible mechanisms that may account for such upregulation.
Migration of Motor Pool Activity in the Spinal Cord Reflects Body Mechanics in Human Locomotion
Authors: Cappellini Germana , Ivanenko Yuri P. , Dominici Nadia , Poppele Richard E. , Lacquaniti Francesco
Published: September 2010

During the evolution of bipedal modes of locomotion, a sequential rostrocaudal activation of trunk muscles due to the undulatory body movements was replaced by more complex and discrete bursts of activity. Nevertheless, the capacity for segmental rhythmogenesis and the rostrocaudal propagation of spinal cord activity has been conserved. In humans, motoneurons of different muscles are arranged in columns, with a specific grouping of muscles at any given segmental level. The muscle patterns of locomotor activity and the biomechanics of the body center of mass have been studied extensively, but their interrelationship remains poorly understood. Here we mapped the electromyographic activity recorded from 30 bilateral leg muscles onto the spinal cord in approximate rostrocaudal locations of the motoneuron pools during walking and running in humans. We found that the rostrocaudal displacements of the center of bilateral motoneuron activity mirrored the changes in the energy due to the center-of-body mass motion. The results suggest that biomechanical mechanisms of locomotion, such as the inverted pendulum in walking and the pogo-stick bouncing in running, may be tightly correlated with specific modes of progression of motor pool activity rostrocaudally in the spinal cord.
Elevation of High-Mobility Group Protein Box-1 in Serum Correlates with Severity of Acute Intracerebral Hemorrhage
Authors: Zhou Yu , Xiong Kun-Lin , Lin Sen , Zhong Qi , Lu Feng-Lin , Liang Hong , Li Jing-Cheng , Wang Jing-Zhou , Yang Qing-Wu
Published: September 2010

High-mobility group protein box-1 (HMGB1) is a proinflammatory involved in many inflammatory diseases. However, its roles in intracerebral hemorrhage (ICH) remain unknown. The purpose of this study was to examine the correlation between changes in serum levels of HMGB1 following acute ICH and the severity of stroke as well as the underlying mechanism. Changes in serum levels of HMGB1 in 60 consecutive patients with primary hemispheric ICH within 12 hours of onset of symptoms were determined. The correlation of HMGB1 with disease severity, IL-6, and TNF-αwas analyzed. Changes in HMGB1 levels were detected with ELISA and Western blot. Compared with normal controls, patients with ICH had markedly elevated levels of HMGB1, which was significantly correlated with the levels of IL-6 and TNF-α, NIHSS score at the 10th day, and mRS score at 3 months. In comparison with the control group, the levels of HMGB1 in the perihematomal tissue in mice with ICH increased dramatically, peaked at 72 hours, and decreased at 5 days. Meanwhile, heme could stimulate cultured microglia to release large amounts of HMGB1 whereasFe2+/3+ions failed to stimulate HMGB1 production from microglia. Our findings suggest that HMGB1 may play an essential role in the ICH-caused inflammatory injury.
Prolonged Use of Ertapenem to Treat Infected Diabetic Foot Ulcers
Authors: Algudkar Ashwin , Ellis Gidon , Ahmad Fareeduddin , Tindall Hilary
Published: September 2010

We present the case of a diabetic man who was successfully treated with ertapenem for over 4 months for severe infection of his foot ulcers. After initial unsuccessful treatment with empirical intravenous antibiotics, ertapenem was started on microbiology advice and led to a marked improvement in the soft-tissue infection. Ertapenem was continued for a total of 137 days under close clinical and biochemical monitoring and produced a complete resolution of the foot infection. This is the first documented case that we know of in which ertapenem has been safely used for this duration of time.
Simulating Species Richness Using Agents with Evolving Niches, with an Example of Galápagos Plants
Authors: Boone Randall B.
Published: September 2010

I sought to evolve plant species richness patterns on 22 Galápagos Islands, Ecuador, as an exploration of the utility of evolutionary computation and an agent-based approach in biogeography research. The simulation was spatially explicit, where agents were plant monocultures defined by three niche dimensions, lava (yes or no), elevation, and slope. Niches were represented as standard normal curves subjected to selection pressure, where neighboring plants bred if their niches overlapped sufficiently, and were considered the same species, otherwise they were different species. Plants that bred produced seeds with mutated niches. Seeds dispersed locally and longer distances, and established if the habitat was appropriate given the seed's niche. From a single species colonizing a random location, hundreds of species evolved to fill the islands. Evolved plant species richness agreed very well with observed plant species richness. I review potential uses of an agent-based representation of evolving niches in biogeography research.
Fixed Simplex Property for Retractable Complexes
Authors: Idzik Adam , Zapart Anna
Published: September 2010

Retractable complexes are defined in this paper. It is proved that they have the fixed simplex property for simplicial maps. This implies the theorem of Wallace and the theorem of Rival and Nowakowski for finite trees: every simplicial map transforming vertices of a tree into itself has a fixed vertex or a fixed edge. This also implies the Hell and Nešetřil theorem: any endomorphism of a dismantlable graph fixes some clique. Properties of recursively contractible complexes are examined.
Hyperhomocysteinaemia in Behçet's Disease
Authors: Hamzaoui Amira , Harzallah Olfa , Klii Rim , Mahjoub Silvia
Published: September 2010

Objectives. The aim of this study was to investigate if hyperhomocysteinaemia is a contributive risk factor for the pathogenesis and the activity of Behçet's disease (BD).Design and Methods. Fifty four patients fullfiling the criteria of the International Study Group for BD were enrolled. Fifty healthy volunteers matched for age and sex with the BD group were included as a negative control group. Patients, with any condition that might affect plasma homocysteine concentration, were excluded.Results. Mean serum homocysteine concentration was significantly higher in patients with BD than in the healthy controls (), in patients with active disease (), and in masculine gender (). There was no significant difference between homocysteine level and clinical involvement.Conclusions. We demonstrated that plasma total homocysteine level (tHcy) is increased in BD and correlated with disease activity. No association was found between homocysteine levels and clinical involvement.
On Reverses of Some Inequalities inn‐Inner Product Spaces
Authors: Chugh Renu , Lather Sushma
Published: September 2010

We present some new reverses of Cauchy‐Bunyakovsky‐Schwarz inequality, and Triangle and Boas‐Bellman Type inequalities in n‐inner product spaces. The results obtained generalize the results of Dragomir(2003–2005)in n‐inner product spaces. Also we provide some applications for determinantal integral inequalities.
Effects of the Hot Alignment of a Power Unit on Oil-Whip Instability Phenomena
Authors: Vania A. , Pennacchi P.
Published: September 2010

This paper shows the results of the analysis of the dynamic behaviour of a power unit, whose shaft-train alignment was significantly influenced by the machine thermal state, that was affected in operating condition by high subsynchronous vibrations caused by oil-whip instability phenomena. The dynamic stiffness coefficients of the oil-film journal bearings of the generator were evaluated considering the critical average journal positions that caused the instability onsets. By including these bearing coefficients in a mathematical model of the fully assembled machine, the real part of the eigenvalue associated with the first balance resonance of the generator rotor became positive. This paper shows the successful results obtained by combining diagnostic techniques based on mathematical models of journal bearings and shaft train with detailed analyses of monitoring data aimed to investigate the effects of the hot alignment of rotating machines on the occurrence of oil-whip instability onsets.
Quality Assessment of Colonoscopy Reporting: Results from a Statewide Cancer Screening Program
Authors: Li Jun , Nadel Marion R. , Poppell Carolyn F. , Dwyer Diane M. , Lieberman David A. , Steinberger Eileen K.
Published: September 2010

This paper aimed to assess quality of colonoscopy reports and determine if physicians in practice were already documenting recommended quality indicators, prior to the publication of a standardized Colonoscopy Reporting and Data System (CO-RADS) in 2007. We examined 110 colonoscopy reports from 2005-2006 through Maryland Colorectal Cancer Screening Program. We evaluated 25 key data elements recommended by CO-RADS, including procedure indications, risk/comorbidity assessments, procedure technical descriptions, colonoscopy findings, specimen retrieval/pathology. Among 110 reports, 73% documented the bowel preparation quality and 82% documented specific cecal landmarks. For the 177 individual polyps identified, information on size and morphology was documented for 87% and 53%, respectively. Colonoscopy reporting varied considerately in the pre-CO-RADS period. The absence of key data elements may impact the ability to make recommendations for recall intervals. This paper provides baseline data to assess if CO-RADS has an impact on reporting and how best to improve the quality of reporting.
General Linear Boundary Value Problem for the Second‐Order Integro‐Differential Loaded Equation with Boundary Conditions Containing Both Nonlocal and Global Terms
Authors: Fatemi M. R. , Aliyev N. A.
Published: September 2010

The paper is devoted to obtaining the sufficient conditions for Fredholm property for the general boundary value problem of the second‐order linear integro‐differential equation. Here, the boundary conditions corresponding with the boundary value problem contain both nonlocal and global terms.
Role of PPAR in Hepatic Carbohydrate Metabolism
Authors: Peeters Annelies , Baes Myriam
Published: September 2010

Tight control of storage and synthesis of glucose during nutritional transitions is essential to maintain blood glucose levels, a process in which the liver has a central role. PPAR is the master regulator of lipid metabolism during fasting, but evidence is emerging for a role of PPAR in balancing glucose homeostasis as well. By using PPAR ligands and PPAR mice, several crucial genes were shown to be regulated by PPAR in a direct or indirect way. We here review recent evidence that PPAR contributes to the adaptation of hepatic carbohydrate metabolism during the fed-to-fasted or fasted-to-fed transition in rodents.
Expression of Heat Shock and Other Stress Response Proteins in Ticks and Cultured Tick Cells in Response toAnaplasmaspp. Infection and Heat Shock
Authors: Villar Margarita , Ayllón Nieves , Busby Ann T. , Galindo Ruth C. , Blouin Edmour F. , Kocan Katherine M. , Bonzón-Kulichenko Elena , Zivkovic Zorica , Almazán Consuelo , Torina Alessandra , Vázquez Jesús , de la Fuente José
Published: September 2010

Ticks are ectoparasites of animals and humans that serve as vectors ofAnaplasmaand other pathogens that affect humans and animals worldwide. Ticks and the pathogens that they transmit have coevolved molecular interactions involving genetic traits of both the tick and the pathogen that mediate their development and survival. In this paper, the expression of heat shock proteins (HSPs) and other stress response proteins (SRPs) was characterized in ticks and cultured tick cells by proteomics and transcriptomics analyses in response toAnaplasmaspp. infection and heat shock. The results of these studies demonstrated that the stress response was activated in ticks and cultured tick cells afterAnaplasmaspp. infection and heat shock. However, in the natural vector-pathogen relationship, HSPs and other SRPs were not strongly activated, which likely resulted from tick-pathogen coevolution. These results also demonstrated pathogen- and tick-specific differences in the expression of HSPs and other SRPs in ticks and cultured tick cells infected withAnaplasmaspp. and suggested the existence of post-transcriptional mechanisms induced byAnaplasmaspp. to control tick response to infection. These results illustrated the complexity of the stress response in ticks and suggested a function for the HSPs and other SRPs duringAnaplasmaspp. infection.
Malignant Fibrous Histiocytoma of the Kidney Treated with Nephrectomy and Adjuvant Radiotherapy: A Case Report
Authors: Marchese Rita , Bufo Pantaleo , Carrieri Giuseppe , Bove Giuseppe
Published: September 2010

Malignant fibrous histiocytoma (MFH) usually presents in the extremities or retroperitoneum. Cases involving the kidney are rare and portend a poor prognosis. Although radical nephrectomy is the most beneficial curative choice for this neoplasm, patients are often treated with adjuvant chemotherapy due to high risk of local recurrence and distant metastases. We describe a case of a 68-year-old woman affected by MFH, treated with both nephrectomy and radiotherapy without systemic therapy showing an unexpected twenty-four-month postsurgery survival outcome.
A Unique Case of Lemierre Syndrome Associated with Thrombophilia in an Adult and the Role of Anticoagulation
Authors: Lakshminarayana Pradeep H. , Woodske Matthew E.
Published: September 2010

Acute septic thrombophlebitis of the internal jugular vein (IJV), better known as Lemierre syndrome, is a rare entity which poses several challenges in management. Treatment involves prompt use of intravenous antibiotics over a prolonged period of time, typically 6–8 weeks. The use of anticoagulation is controversial, but indicated for some. We describe the first reported case of Lemierre syndrome associated with a hypercoagulable state in an adult. We propose that all patients with Lemierre syndrome should be evaluated for hypercoagulable states and that the indications for anticoagulation in Lemierre syndrome are (1) propagation or nonresolution of IJV thrombus despite antibiotics and (2) identification of a hypercoagulable state, as in our case.
Pigmentation, Melanocyte Colonization, and p53 Status in Basal Cell Carcinoma
Authors: Frey Lídia M. , Houben Roland , Bröcker Eva-B.
Published: September 2010

Basal cell carcinoma (BCC) is the most common neoplasm in the Caucasian population. Only a fraction of BCC exhibits pigmentation. Lack of melanocyte colonization has been suggested to be due to p53-inactivating mutations in the BCC cells interfering with the p53-proopiomelanocortin pathway and the production of alpha melanocyte-stimulating hormone in the tumor. To evaluate this, we determined tumor pigmentation as well as expression of melan-A and of p53 in 49 BCC tissues by means of immunohistochemistry. As expected, we observed a positive relation between tumor pigmentation and melan-A positive intra-tumoral melanocytes. Melanocyte colonization and, to a lesser extent, p53 overexpression showed intraindividual heterogeneity in larger tumors. p53 overexpression, which is indicative of p53 mutations, was not correlated to melanocyte colonization of BCC. Sequencing of exon 5–8 of the p53 gene in selected BCC cases revealed that colonization by melanocytes and BCC pigmentation is neither ablated by p53 mutations nor generally present in BCCs with wild-type p53.
Cellular Origin of Spontaneous Ganglion Cell Spike Activity in Animal Models of Retinitis Pigmentosa
Authors: Margolis David J. , Detwiler Peter B.
Published: September 2010

Here we review evidence that loss of photoreceptors due to degenerative retinal disease causes an increase in the rate of spontaneous ganglion spike discharge. Information about persistent spike activity is important since it is expected to add noise to the communication between the eye and the brain and thus impact the design and effective use of retinal prosthetics for restoring visual function in patients blinded by disease. Patch-clamp recordings from identified types of ON and OFF retinal ganglion cells in the adult (36–210 d old)rd1mouse show that the ongoing oscillatory spike activity in both cell types is driven by strong rhythmic synaptic input from presynaptic neurons that is blocked by CNQX. The recurrent synaptic activity may arise in a negative feedback loop between a bipolar cell and an amacrine cell that exhibits resonant behavior and oscillations in membrane potential when the normal balance between excitation and inhibition is disrupted by the absence of photoreceptor input.
Dark Matter Halos from the Inside Out
Authors: Taylor James E.
Published: September 2010

The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter “halos” provide the scaffolding for all luminous structures in the universe, and their properties comprise an essential part of the current cosmological model. I review the internal properties of dark matter halos, focussing on the simple universal trends predicted by numerical simulations of structure formation. Simulations indicate that halos should all have roughly the same spherically averaged density profile and kinematic structure and predict simple distributions of shape, formation history, and substructure in density and kinematics, over an enormous range of halo mass and for all common variants of the concordance cosmology. I describe observational progress towards testing these predictions by measuring masses, shapes, profiles, and substructure in real halos using baryonic tracers or gravitational lensing. An important property of simulated halos (possibly the most important property) is their dynamical “age”, or degree of internal relaxation. I review recent gravitational lensing studies of galaxy clusters which will measure substructure and relaxation in a large sample of individual cluster halos, producing quantitative measures of age that are well matched to theoretical predictions.
Can Basic Risk Research Help in the Prevention of Childhood and Adolescent Depression? Examining a Cognitive and Emotional Regulation Approach
Authors: Rice Frances , Rawal Adhip
Published: September 2010

This paper aims to highlight ways in which basic research findings in the field of childhood and adolescent depression can help to inform and refine preventive intervention efforts. We selectively review basic research evidence from community, clinical, and high-risk populations that identifies cognitive mechanisms (thought processes and reactions to negative affect) and emotional regulation as key processes involved in the onset and maintenance of depression. We focus on cognitive and emotional mechanisms in order to allow comparability with the majority of current preventive interventions. A range of basic research strategies and studies are then suggested that could be employed to help the development and refinement of prevention strategies. These include the need for prospective longitudinal studies to identify causal risk and protective factors, an integration of research approaches and methods, and a focus on understanding potential aetiological heterogeneity between childhood and adolescent depression.