bluuebunny/crossref_metadata_2025 huggingface dataset:
LOW ENERGY EFFECTIVE ACTION OF QUANTUM GRAVITY AND THE NATURALNESS PROBLEM
Authors: KAWAI HIKARU
Published: February 2013

In quantum gravity or string theory, it is natural to take the topology change of the space into account. We consider the low energy effective action for such case and show that it does not have a simple form of the local action but has a multilocal form. Actually, in quantum gravity or matrix model, there are some mechanisms that the low energy effective action becomes S eff = ∑ici Si + ∑ijcijSiSj + ∑ijkcijk Si Sj Sk + ⋯, where Si is a local action of the form [Formula: see text]. We further discuss that the topology change of the space naturally leads to the multiverse in which indefinite number of macroscopic universes exist in parallel. In this case, the space–time coordinates x in the multilocal action may sit either in the same universe or in different ones. We then consider the wave function of the entire multiverse, and see how the locality and causality are recovered in such theory. We further discuss the possibility of solving the naturalness problem. In doing so, we need to introduce some assumptions to interpret the multiverse wave function. We consider two different possibilities. One is to simply assume the probabilistic interpretation for the multiverse wave function. The other is to assume infrared cutoff independence of the partition function of the universe. In both cases, we find that the big fix occurs, in which all the coupling constants in the low energy physics are determined by the dynamics of the multiverse. Actually, we find that they are fixed in such a way that the total entropy of the universe at the late stage (in the far future) is maximized. Although the argument here is similar to Coleman's original one given in the late 1980s, our results are based on Lorentzian signature theory and the dynamical mechanism is rather different.
THE MARSDEN–WEINSTEIN REDUCTION STRUCTURE OF INTEGRABLE DYNAMICAL SYSTEMS AND A GENERALIZED EXACTLY SOLVABLE QUANTUM SUPERRADIANCE MODEL
Authors: BOGOLUBOV N. N. , PRYKARPATSKY Y. A.
Published: February 2013

An approach to describing nonlinear Lax type integrable dynamical systems of modern mathematical and theoretical physics, based on the Marsden–Weinstein reduction method on canonically symplectic manifolds with group symmetry, is proposed. Its natural relationship with the well-known Adler–Kostant–Souriau–Berezin–Kirillov method and the associated R-matrix approach is analyzed.

A new generalized exactly solvable spatially one-dimensional quantum superradiance model, describing a charged fermionic medium interacting with external electromagnetic field, is suggested. The Lax type operator spectral problem is presented, the related R-structure is calculated. The Hamilton operator renormalization procedure subject to a physically stable vacuum is described, the quantum excitations and quantum solitons, related with the thermodynamical equilibrity of the model, are discussed.
BAND GAP OPENING EFFECT ON THE TRANSPORT PROPERTIES OF BILAYER GRAPHENE SUPERLATTICE
Authors: SATTARI FARHAD , FAIZABADI EDRIS
Published: February 2013

We have investigated electronic transport of charge carriers in a gapped bilayer graphene superlattice (GBGS), based on transfer matrix method. We have found that conductivity of the system has an oscillatory behavior respect to the gap value. As the gap value is simply changeable by external voltage in bilayer graphene, the conductivity can be controlled by gate voltage. It also has been shown that transmission probability for normal incident angle depends on barrier width in presence of band gap within barrier region. As a result, a GBGS behaves very differently compared to a gapless bilayer graphene superlattice.
ORTHOGONAL DIRAC SEMIMETAL ON HONEYCOMB LATTICE
Authors: ZHONG YIN , LUO HONG-GANG
Published: February 2013

Recently, a concept of orthogonal metal has been introduced to reinterpret the disordered state of slave-spin representation in the Hubbard model as an exotic gapped metallic state. We have extended this concept to study the slave-spin representation of Hubbard model on the honeycomb lattice. It is found that a novel gapped metallic state coined orthogonal Dirac semimetal is identified. Such state corresponds to the disordered phase of slave-spin and has the same thermal-dynamical and transport properties as Dirac semimetal but its singe-particle excitation is gapped.
STATE-OF-THE-ART INVESTIGATIONS ON STATISTICAL MECHANICS FOR SELF-GRAVITATING SYSTEMS
Authors: HE PING
Published: February 2013

The statistical mechanics of collisionless self-gravitating systems is a longstanding puzzle, which has not yet been successfully solved. We performed preliminary investigations and then formulated a framework of the entropy-based equilibrium statistical mechanics for collisionless self-gravitating systems. This theory is based on the Boltzmann–Gibbs entropy and includes the generalized virial equations as additional constraints. With the truncated distribution function to the lowest order, we derived a set of second-order equations for the equilibrium states of the system, and solved the numerical solutions of these equations. It is found that there are three types of solutions for these equations. Both the isothermal and divergent solutions are thermally unstable and have unconfined density profiles with infinite mass, energy and spatial extent. The convergent solutions, however, seem to be reasonable. These solutions are just the lowest-order approximation, but they have already manifested the qualitative success of our theory. The second-order variations of the entropy functional indicate that the stationary solutions are neither maximum nor minimum, but saddle-point solutions. Inspired by the saddle-point solutions, we distinguish between two types of perturbations in self-gravitating systems, namely, the large-scale mass perturbation and the small-scale density perturbation, which correspond to long-range violent relaxation and short-range relaxation/Landau damping, respectively, which operate in different fashions. This result is consistent with Antonov's proof, or Binney's argument, that there are no global maximum entropy states for self-gravitating systems. These investigations indicate the achievements that we have made towards this long-standing unsolved problem on the statistical mechanics of self-gravitating systems.
SIMILARITY INDEX BASED ON THE INFORMATION OF NEIGHBOR NODES FOR LINK PREDICTION OF COMPLEX NETWORK
Authors: WANG JING , RONG LILI
Published: February 2013

Link prediction in complex networks has attracted much attention recently. Many local similarity measures based on the measurements of node similarity have been proposed. Among these local similarity indices, the neighborhood-based indices Common Neighbors (CN), Adamic-Adar (AA) and Resource Allocation (RA) index perform best. It is found that the node similarity indices required only information on the nearest neighbors are assigned high scores and have very low computational complexity. In this paper, a new index based on the contribution of common neighbor nodes to edges is proposed and shown to have competitively good or even better prediction than other neighborhood-based indices especially for the network with low clustering coefficient with its high efficiency and simplicity.
INTERCONNECT MODELING WITH THE EXISTENCE OF LINE INDUCTANCE
Authors: EL-MOURSY MAGDY A. , SHAWKEY HEBA A.
Published: February 2013

Simple uniform reduced order model is used to model RLC interconnect lines. Waveform characterization is used to evaluate the accuracy of the adopted model. Few number of sections are shown to achieve high accuracy of modeling the RLC interconnect. As compared to RC lines, less than five times the number of sections is sufficient to model RLC lines. The model is shown to be accurate for wide range of relative impedance of the driver, the line, and the load. Look-up tables are provided to simplify the process of choosing the best interconnect section model to characterize an RLC interconnect line. The tables are shown to be accurate for wide range of relative impedance. The presented model reduces the simulation time while keeping the simulation accuracy. The simulation time can be reduced by up to 72% with less than 10% reduction in accuracy using the provided tables. The tables provide a simple and quick mean to characterize an RLC interconnect which is necessary for performance evaluation in digital circuits.
A NOVEL CURRENT-TUNABLE MONOSTABLE MULTIVIBRATOR USING SINGLE DISO-OTA
Authors: CHIEN HUNG-CHUN
Published: February 2013

This paper proposes a novel monostable multivibrator featuring compact topology and current-tunable property. The proposed circuit was composed of a single differential input single output operational transconductance amplifier (DISO-OTA) with a few passive components. It was operated by a negative-edge triggering signal to generate an output pulse. The pulse height and width were tunable by the bias current of DISO-OTA and the external resistors. The proposed scheme is more compact than the existing topologies. This paper presents the circuit operations and a discussion of the non-ideal issues and design considerations. To demonstrate the feasibility of the proposed circuit, a prototype circuit built with commercially available DISO-OTA IC was used to execute the experimental tests. Is-Spice simulation and experimental results were consistent with theoretical analysis.
SYSTEMATIC SYNTHESIS OF OTA-BASED T-T FILTERS USING NAME METHOD
Authors: LI YONG-AN
Published: February 2013

According to the terminal relations of the DO-OTA, eight nullor–mirror models for the DO-OTA are presented in this paper, Moreover, the NAME method for two different classes of T-T filters is considered. The class I filters, employing three SISO-OTAs, have 16 different forms, and the class II filters, employing one SISO-OTA and one DISO-OTA or one SIDO-OTA, have eight different forms. Due to use of canonic number of components, the circuits are easy to be integrated and their parameters can be tuned electronically through tuning bias currents of the OTAs. The MULTISIM simulation results have been included to verify the workability of the derived circuit.
CONCEPTUAL ISSUES CONCERNING GENERALIZED PARTON DISTRIBUTIONS
Authors: JI CHUENG-RYONG , BAKKER BERNARD L. G.
Published: February 2013

We review the interface between the current theoretical framework based on generalized parton distributions (GPDs) and experimental measurements of deeply virtual Compton scattering (DVCS) observables. We find that the present theoretical framework needs to be extended to cover the current and future DVCS experiments. The current formulation is based on the quantum chromodynamics factorization of the handbag diagrams, relying on handbag dominance. Our examination reveals that the handbag diagrams by themselves do not satisfy electromagnetic gauge invariance. Our numerical estimates of the DVCS amplitudes in a solvable model indicate that the handbag contribution is not sufficient to saturate the exact result. Assuming the extraction of GPDs is made, we analyzed the crossover point in GPDs, important for the single spin asymmetry seen in DVCS experiments. We found that the inclusion of the higher Fock states is essential to explain the available data of single spin asymmetry.
GENERAL RELATIVISTIC EFFECT ON THE ENERGY DEPOSITION RATE FOR NEUTRINO PAIR ANNIHILATION ABOVE THE EQUATORIAL PLANE ALONG THE SYMMETRY AXIS NEAR A ROTATING NEUTRON STAR
Authors: MALLICK RITAM , BHATTACHARYYA ABHIJIT , GHOSH SANJAY K. , RAHA SIBAJI
Published: February 2013

The estimate of the energy deposition rate (EDR) for neutrino pair annihilation has been carried out. The EDR for the neutrinos coming from the equatorial plane of a rotating neutron star is calculated along the rotation axis using the Cook–Shapiro–Teukolsky metric. The neutrino trajectories and hence the neutrinos emitted from the disk are affected by the redshift due to disk rotation and gravitation. The EDR is very sensitive to the value of the temperature and its variation along the disk. The rotation of the star has a negative effect on the EDR; it decreases with increase in rotational velocity.
THE RESPONSE FUNCTION OF THE 4He, 16O AND 40Ca NUCLEI IN THE HARMONIC OSCILLATOR SHELL MODEL AND THE IMPULSE APPROXIMATIONS
Authors: MODARRES M. , YOUNESIZADEH Y.
Published: February 2013

In this work, the response functions (RFs) of the 4 He , 16 O and 40 Ca nuclei are calculated in the harmonic oscillator shell model (HOSM) and the impulse approximation (IA). First, the one-body momentum distribution and the one-body spectral functions for these nuclei are written in the HOSM configuration. Then, their RFs are calculated, in the two frameworks, namely the spectral and the momentum distribution functions, within the IA. Unlike our previous work, no further assumption is made to reduce the analytical complications. For each nucleus, it is shown that the (RF) evaluated using the corresponding spectral function has a sizable shift, with respect to the one calculated in terms of the momentum distribution function. It is concluded that for the heavier nuclei, this shift increases and reaches nearly to a constant value (approximately 62 MeV), i.e., similar to that of nuclear matter. It is discussed that in the nuclei with the few nucleons, the above shift can approximately be ignored. This result reduces the theoretical complication for the explanation of the ongoing deep inelastic scattering (DIS) experiments of 3 H or 3 H nucleus target in the Jefferson Laboratory. On the other hand, it is observed that in the heavier nuclei, the RF heights (width) decrease (increase), i.e., the comparison between the theoretical and the experimental electron nucleus scattering cross-section is more sensible for heavy nuclei rather than the light ones.
STRANGE BARYONS, NUCLEAR DRIPLINE AND SHRINKAGE: A RELATIVISTIC MEAN FIELD STUDY
Authors: BHOWMICK BIPASHA , BHATTACHARYYA ABHIJIT , GANGOPADHYAY G.
Published: February 2013

Neutron and proton driplines of single-Λ and double-Λ hypernuclei, Ξ- hypernuclei as well as normal nuclei are studied within a relativistic mean field approach using an extended form of the FSU Gold Lagrangian density. Hyperons are found to produce bound nuclei beyond the normal nuclear driplines. Radii are found to decrease in hypernuclei near the driplines, in line with observations in light Λ hypernuclei near the stability valley. The inclusion of a Ξ- introduces a much larger change in radii than one or more Λ's.
DISCOVERING AND MANAGING SOCIAL COMPOSITIONS IN COLLABORATIVE ENTERPRISE CROWDSOURCING SYSTEMS
Authors: SKOPIK FLORIAN , SCHALL DANIEL , DUSTDAR SCHAHRAM
Published: February 2013

Crowdsourcing is an increasingly used model to outsource certain tasks to be carried out by external experts on the Web. Especially when lacking experience or expertise with certain task types, crowdsourcing offers a convenient way to receive instant support. In this paper, we introduce an in-house enterprise crowdsourcing model, which leverages the crowdsourcing concept and transfers it to traditional organizations. Here, a company's staff is considered a crowd that — besides its regularly assigned tasks — can also receive tasks from colleagues from other departments and across hierarchical structures. The aim is to offer instant support and utilize free capacities throughout a large organization more efficiently. In our work, we describe this concept and supporting mechanisms in context of an agile software development use case. However, in contrast to usually crowdsourced microtasks, complex software architectures usually consist of tens and hundreds of connected modules that can be potentially crowdsourced. These technical dependencies between modules require active coordination and interactions between crowd members that process the single artifacts. Hence, technical dependencies of artifacts result in social dependencies of collaborating crowd members that create them. In order to efficiently discover member compositions based on artifact dependencies, we introduce an indexing and discovery approach based on subgraph matching. Typically, assigning tasks to well-rehearsed teams results in more reliable task processing, faster results, and higher quality of work. We evaluate our approach in terms of system scalability and overall applicability by mining and analyzing the popular SourceForge community. We show that our approach of member composition discovery is feasibly in terms of scalability and quality of discovery results. Our findings deliver important input for the design and implementation of supporting information systems for future large-scale collaboration platforms.
COHERENT STATE OF α-DEFORMED WEYL–HEISENBERG ALGEBRA
Authors: DEHDASHTI SH. , MAHDIFAR A. , ROKNIZADEH R.
Published: February 2013

At first, we introduce α-deformed algebra as a kind of generalization of the Weyl–Heisenberg algebra so that we get the su(2)- and su(1, 1)-algebras whenever α has specific values. After that, we construct coherent states of this algebra. Third, a realization of this algebra is given in the system of a harmonic oscillator confined at the center of a potential well. Then, we introduce two-boson realization of the α-deformed Weyl–Heisenberg algebra and use this representation to write α-deformed coherent states in terms of the two modes number states. Following these points, we consider mean number of excitations (we call them in general photons) and Mandel parameter as statistical properties of the α-deformed coherent states. Finally, the Fubini–Study metric is calculated for the α-coherent states manifold.
A LERAY SPECTRAL SEQUENCE FOR NONCOMMUTATIVE DIFFERENTIAL FIBRATIONS
Authors: BEGGS EDWIN , MASMALI IBTISAM
Published: February 2013

This paper describes the Leray spectral sequence associated to a differential fibration. The differential fibration is described by base and total differential graded algebras. The cohomology used is noncommutative differential sheaf cohomology. For this purpose, a sheaf over an algebra is a left module with zero curvature covariant derivative. As a special case, we can recover the Serre spectral sequence for a noncommutative fibration.
MICROMECHANICAL MODELING OF ADVANCED COMPOSITES
Authors: BACARREZA O. , ABE D. , ALIABADI M. H. , KOPULA RAGAVAN N.
Published: February 2013

Advanced composites are increasingly being used as a structural material because of their balanced properties, higher impact resistance, and easier handling and fabrication compared with unidirectional composites. However, complex architecture of these composites leads to difficulties in predicting the mechanical response necessary for product design. Different methods for micromechanical analysis for the evaluation of effective mechanical properties of advanced composites are compared. Difficulties in modeling are highlighted and recommendations are given for micromechanical analysis using the finite element method.
FLUCTUATIONS IN LIPID BILAYERS: ARE THEY UNDERSTOOD?
Authors: SCHMID FRIEDERIKE
Published: February 2013

We review recent computer simulation studies of undulating lipid bilayers. Theoretical interpretations of such fluctuating membranes are most commonly based on generalized Helfrich-type elastic models, with additional contributions of local "protrusions" and/or density fluctuations. Such models provide an excellent basis for describing the fluctuations of tensionless bilayers in the fluid Lαphase at a quantitative level.

However, this description is found to fail for membranes in the gel phase and for membranes subject to high tensions. The fluctuations of tilted gel membranes (Lβ′phase) show a signature of the modulated ripple structure Pβ′, which is a nearby phase observed in the pretransition regime between the Lαand Lβ′state. This complicates a quantitative analysis on mesoscopic length scales. In the case of fluid membranes under tension, the large-wavelength fluctuation modes are found to be significantly softer than predicted by theory.

In the latter context, we also address the general problem of the relation between frame tension and the fluctuation tension, which has been discussed somewhat controversially in recent years. Simulations of very simple model membranes with fixed area show that the fluctuations should be controlled by the frame tension, and not by the internal tension.
Regional relation between skin blood flow and sweating to passive heating and local administration of acetylcholine in young, healthy humans
Authors: Smith Caroline J. , Kenney W. Larry , Alexander Lacy M.
Published: February 2013

Regional variation in sweating over the human body is widely recognized yet variation in vasomotor responses and mechanisms causing this variation remain unclear. This study aimed to explore the relation between regional sweating rates (RSR) and skin blood flow (SkBF) responses to thermal and pharmacological stimuli in young, healthy subjects. In nine subjects (23 ± 3 yr), intradermal microdialysis (MD) probes were inserted into the ventral forearm, abdomen, thigh, and lower back and perfused with lactated Ringer solution. RSR over each MD membrane were measured using ventilated capsules with a laser Doppler probe housed in each capsule for measurement of red cell flux (laser Doppler flux, LDF) as an index of SkBF. Subjects completed a whole body heating protocol to 1°C rise in oral temperature and an acetylcholine dose response (ACh 1 × 10−7-0.1 M; mean skin temperature 34°C). Maximal LDF were obtained at the end of both protocols (50 mM sodium nitroprusside).During heating RSR varied among sites ( P < 0.0001) and was greater on the back versus other sites ( P < 0.05), but LDF was similar between sites ( P = 0.343). RSR and SkBF showed a strong relation during initial (arm: r = 0.77 ± 0.09, thigh: r = 0.81 ± 0.08, abdomen: r = 0.89 ± 0.04, back: r = 0.86 ± 0.04) but not latter stages of heating. No differences in RSR ( P = 0.160) or SkBF (LDF, P = 0.841) were observed between sites during ACh perfusion. Taken together, these data suggest that increases in SkBF are necessary to initiate and increase sweating, but further rises in RSR are not fully dependent on SkBF in a dose-response manner. Furthermore, RSR cannot be explained by cholinergic sensitivity or variation in SkBF.
Divergent phenotype of rat thoracic and abdominal perivascular adipose tissues
Authors: Padilla Jaume , Jenkins Nathan T. , Vieira-Potter Victoria J. , Laughlin M. Harold
Published: February 2013

Perivascular adipose tissue (PVAT) is implicated as a source of proatherogenic cytokines. Phenotypic differences in local PVAT depots may contribute to differences in disease susceptibility among arteries and even regions within an artery. It has been proposed that PVAT around the abdominal and thoracic aorta shares characteristics of white and brown adipose tissue (BAT), respectively; however, a detailed comparison of the phenotype of these PVAT depots has not been performed. Using young and older adult rats, we compared the phenotype of PVATs surrounding the abdominal and thoracic aorta to each other and also to epididymal white and subscapular BAT. Compared with young rats, older rats exhibited greater percent body fat (34.5 ± 3.1 vs. 10.4 ± 0.9%), total cholesterol (112.2 ± 7.5 vs. 58.7 ± 6.3 mg/dl), HOMA-insulin resistance (1.7 ± 0.1 vs. 0.9 ± 0.1 a.u.), as well as reduced ACh-induced relaxation of the aorta (maximal relaxation: 54 ± 10 vs. 77 ± 6%) (all P < 0.05). Expression of inflammatory genes and markers of immune cell infiltration were greater in abdominal PVAT than in thoracic PVAT, and overall, abdominal and thoracic PVATs resembled the phenotype of white adipose tissue (WAT) and BAT, respectively. Histology and electron microscopy indicated structural similarity between visceral WAT and abdominal PVAT and between BAT and thoracic PVAT. Our data provide evidence that abdominal PVAT is more inflamed than thoracic PVAT, a difference that was by and large independent of sedentary aging. Phenotypic differences in PVAT between regions of the aorta may be relevant in light of the evidence in large animals and humans that the abdominal aorta is more vulnerable to atherosclerosis than the thoracic aorta.
Dietary iron restriction inhibits progression of diabetic nephropathy indb/dbmice
Authors: Ikeda Yasumasa , Enomoto Hideaki , Tajima Soichiro , Izawa-Ishizawa Yuki , Kihira Yoshitaka , Ishizawa Keisuke , Tomita Shuhei , Tsuchiya Koichiro , Tamaki Toshiaki
Published: February 2013

Excess iron causes oxidative stress through hydroxyl-radical production via Fenton/Haber-Weiss reactions. Recently, body iron reduction has been found to ameliorate diabetes. In the present study, we examined the protective effect of dietary iron restriction against diabetic nephropathy in the db/db mouse model of diabetic nephropathy using db/m mice as controls. The db/db mice were divided into two groups and fed a normal diet (ND) or a low-iron diet (LID). Increasing urinary albumin excretion was observed in the ND db/db mice, but this was suppressed in db/db mice with LID. Histologically, the db/db mice in the ND group had increased glomerular volume and mesangial area compared with the LID group. Augmented deposition of extracellular matrixes was decreased in db/db mice with LID. In terms of oxidative stress, increased superoxide production observed in the kidneys of the ND db/db mice was diminished in the LID group. NADPH oxidase activity and renal expression of NADPH oxidase components p22phoxand NADPH oxidase 4 (NOX4) were augmented in the ND group, and this was abolished by LID. There were no differences in expression of renal iron importers, transferrin receptor, or divalent metal transporter-1 between db/m mice and db/db mice. The level of ferroportin, an iron exporter, increased in the kidneys of the db/db mice. Urinary iron excretion was significantly higher in ND db/db mice and was reduced in the LID group. These findings suggest that dietary iron restriction exerts a preventive effect on the progression of diabetic nephropathy partly due to the reduction of oxidative stress.
Inhibition of Notch pathway attenuates the progression of human immunodeficiency virus-associated nephropathy
Authors: Sharma Madhulika , Magenheimer Lynn K. , Home Trisha , Tamano Karen N. , Singhal Pravin C. , Hyink Deborah P. , Klotman Paul E. , Vanden Heuvel Gregory B. , Fields Timothy A.
Published: February 2013

The Notch pathway is an evolutionarily conserved signaling cascade that is critical in kidney development and has also been shown to play a pathogenetic role in a variety of kidney diseases. We have previously shown that the Notch signaling pathway is activated in human immunodeficiency virus-associated nephropathy (HIVAN) as well as in a rat model of the disease. In this study, we examined Notch signaling in the well established Tg26 mouse model of HIVAN. Notch signaling components were distinctly upregulated in the kidneys of these mice as well as in immortalized podocytes derived from these mice. Notch1 and Notch4 were upregulated in the Tg26 glomeruli, and Notch4 was also expressed in tubules. Notch ligands Jagged1, Jagged2, Delta-like1, and Delta-like 4 were all upregulated in the tubules of Tg26 mice, but glomeruli showed minimal expression of Notch ligands. To examine a potential pathogenetic role for Notch in HIVAN, Tg26 mice were treated with GSIXX, a gamma secretase inhibitor that blocks Notch signaling. Strikingly, GSIXX treatment resulted in significant improvement in both histological kidney injury scores and renal function. GSIXX-treated Tg26 mice also showed diminished podocyte proliferation and dedifferentiation, cellular hallmarks of the disease. Moreover, GSIXX blocked podocyte proliferation in vitro induced by HIV proteins Nef and Tat. These studies suggest that Notch signaling can promote HIVAN progression and that Notch inhibition may be a viable treatment strategy for HIVAN.
Nuclear factor of activated T cells mediates RhoA-induced fibronectin upregulation in glomerular podocytes
Authors: Zhu Lei , Qi Xiao-Yan , Aoudjit Lamine , Mouawad Flaviana , Baldwin Cindy , Nattel Stanley , Takano Tomoko
Published: February 2013

Glomerulosclerosis is featured by accumulation of the extracellular matrixes in the glomerulus. We showed previously that activation of the small GTPase RhoA in podocytes induces heavy proteinuria and glomerulosclerosis in the mouse. In the current study, we investigated the mechanism by which RhoA stimulates the production of one of the extracellular matrixes, fibronectin, by podocytes, specifically testing the role of nuclear factor of activated T cells (NFAT). Expression of constitutively active RhoA in cultured podocytes activated the fibronectin promoter, upregulated fibronectin protein, and activated NFAT. Expression of constitutively active NFAT in podocytes also activated the fibronectin promoter and upregulated fibronectin protein. RhoA-induced NFAT activation and fibronectin upregulation were both dependent on the calcium/calmodulin pathway and Rho kinase. NFAT activation was also observed in vivo in the rat and mouse models of podocyte injury and proteinuria, and NFAT inhibition ameliorated fibronectin upregulation in the latter. RhoA activation induced a rise of intracellular calcium ion concentration ([Ca2+]i), which was at least in part dependent on the transient receptor potential canonical 6 (TRPC6) cation channel. The results indicate that RhoA activates NFAT by inducing a rise of [Ca2+]iin podocytes, which in turn contributes to fibronectin upregulation. This pathway may be responsible for the pathogenesis of certain glomerular diseases such as hypertension-mediated glomerulosclerosis.
Tamm-Horsfall protein translocates to the basolateral domain of thick ascending limbs, interstitium, and circulation during recovery from acute kidney injury
Authors: El-Achkar Tarek M. , McCracken Ruth , Liu Yan , Heitmeier Monique R. , Bourgeois Soline , Ryerse Jan , Wu Xue-Ru
Published: February 2013

Tamm-Horsfall protein (THP) is a glycoprotein normally targeted to the apical membrane domain of the kidney's thick ascending limbs (TAL). We previously showed that THP of TAL confers protection to proximal tubules against acute kidney injury (AKI) via a possible cross talk between the two functionally distinct tubular segments. However, the extent, timing, specificity, and functional effects of basolateral translocation of THP during AKI remain unclear. Using an ischemia-reperfusion (IRI) model of murine AKI, we show here that, while THP expression in TAL is downregulated at the peak of injury, it is significantly upregulated 48 h after IRI. Confocal immunofluorescence and immunoelectron microscopy reveal a major redirection of THP during recovery from the apical membrane domain of TAL towards the basolateral domain, interstitium, and basal compartment of S3 segments. This corresponds with increased THP in the serum but not in the urine. The overall epithelial polarity of TAL cells does not change, as evidenced by correct apical targeting of Na+-K+-2Cl cotransporter (NKCC2) and basolateral targeting of Na+-K+-ATPase. Compared with the wild-type, THP−/−mice show a significantly delayed renal recovery after IRI, due possibly to reduced suppression by THP of proinflammatory cytokines and chemokines such as monocyte chemoattractant protein-1 during recovery. Taken together, our data suggest that THP redistribution in the TAL after AKI is a protein-specific event and its increased interstitial presence negatively regulates the evolving inflammatory signaling in neighboring proximal tubules, thereby enhancing kidney recovery. The increase of serum THP may be used as a prognostic biomarker for recovery from AKI.
Infected Completely Isolated Enteric Duplication Cyst Management with Percutaneous Drainage and Surgical Excision after Retreat of Infection: A Case Report
Authors: Kyriakos Neofytou , Andreas Chysochos , Elena Sammouti , Charalampos Andreou , Chrisanthos Georgiou
Published: February 2013

Duplication cysts (DCs) of alimentary tract are rare congenital malformations. They are firmly attached to the wall of the gastrointestinal tract and they are supplied by surrounding mesenteric blood vessels. More than 80% of cases occur before the age of two years and only a minority of cases present in adulthood. “Completely isolated duplication” of the alimentary tract is an extremely rare variety of gastrointestinal duplications. They have gastrointestinal epithelial and wall characteristics without an anatomic association with the alimentary tract. Their main characteristic is that they have their own blood supply. A 20-year-old male was admitted to our department with symptoms persisting for a period of one week prior to admission, which included abdominal pain, fever, and a palpable abdominal mass. CT revealed an unexplained intraperitoneal abscess. This case represents a rare clinical example of infected isolated duplication cyst managed with percutaneous drainage and surgical excision of the cyst 3 weeks later. To the best of our knowledge, this is the first reported case to use this approach.
Indoor Mobile Localization in Wireless Sensor Network under Unknown NLOS Errors
Authors: Cheng Long , Wu Hao , Wu Chengdong , Zhang Yunzhou
Published: February 2013

Localization is one of the key techniques in wireless sensor network. One of the main problems in indoor mobile localization is non-line-of-sight (NLOS) propagation. And the NLOS effects will lead to a large localization error. So the NLOS problem is the biggest challenge for accurate mobile location estimation in WSN. In this paper, we propose a likelihood matrix correction based mixed Kalman and H-infinity filter (LC-MKHF) method. A likelihood matrix based correction method is firstly proposed to correct the LOS and NLOS measurements. This method does not need the prior information about the statistical properties of the NLOS errors. So it is independent of the physical measurement ways. And then a mixed Kalman and H-infinity filter method is proposed to improve the range measurement. Simulation results show that the LC-MKHF algorithm has higher estimate accuracy in comparison with no-filter, Kalman filter, and H-infinity filter methods. And it is robust to the NLOS errors.
Inflammatory Burden but Not Diabetes Mellitus Influences in Prognosis of Endovascular Revascularization in Peripheral Arterial Disease
Authors: Bleda Silvia , de Haro Joaquin , Varela Cesar , Lopez de Maturana Ignacio , Rodriguez Javier , Acin Francisco
Published: February 2013

Aims. To determine the effect of inflammatory preoperative burden on the incidence of reintervention and mortality after endovascular therapy (EVT) and to investigate if diabetes mellitus (DM) is involved in these results. Material and Methods. A prospective cohort study with 12-month follow-up period in patients with peripheral artery disease was carried out. hsCRP and fibrinogen assessments were determined. Results. 85 diabetic and 58 nondiabetic patients were included. An increase between basal hsCRP (11.8 mg/L (10.2; 21.5) versus 4.3 mg/L (1.8; 13.9), P<0.001) and fibrinogen levels (450 mg/dL (425; 479.1) versus 369 mg/dL (268; 419), P<0.001) and the incidence of death during followup was found. A significant increase between higher hsCRP and fibrinogen basal levels and the incidence of reintervention during the follow-up period was also noted (P=0.001 and P=0.04, resp.,). There was no difference between DM and non-DM patients in the 1-year need of reintervention (33.3% versus 45%, P=0.15, resp.,). Basal hsCRP and fibrinogen levels did not significantly differ between DM and non-DM patients who needed reintervention. Conclusions. The prognosis of the EVT is likely marked by the previous inflammatory load, regardless of DM.
PPARγNetworks in Cell Signaling: Update and Impact of Cyclic Phosphatidic Acid
Authors: Tsukahara Tamotsu
Published: February 2013

Lysophospholipid (LPL) has long been recognized as a membrane phospholipid metabolite. Recently, however, the LPL has emerged as a candidate for diagnostic and pharmacological interest. LPLs include lysophosphatidic acid (LPA), alkyl glycerol phosphate (AGP), cyclic phosphatidic acid (cPA), and sphingosine-1-phosphate (S1P). These biologically active lipid mediators serve to promote a variety of responses that include cell proliferation, migration, and survival. These LPL-related responses are mediated by cell surface G-protein-coupled receptors and also intracellular receptor peroxisome proliferator-activated receptor gamma (PPARγ). In this paper, we focus mainly on the most recent findings regarding the biological function of nuclear receptor-mediated lysophospholipid signaling in mammalian systems, specifically as they relate to health and diseases. Also, we will briefly review the biology of PPARγand then provide an update of lysophospholipids PPARγligands that are under investigation as a therapeutic compound and which are targets of PPARγrelevant to diseases.
Bullying and Its Associated Factors among School‐Aged Adolescents in Thailand
Authors: Pengpid Supa , Peltzer Karl
Published: February 2013

The aim of this study were to assess bullying and its associated factors in school‐going adolescents in Thailand. Using data from the Thailand Global School‐Based Student Health Survey (GSHS) 2008, the prevalence of being bullied and its associated factors among adolescents (N = 2758) was assessed. The study found an overall prevalence of being bullied on one or more days during the past 30 days of 27.8%, 32.9% among males and 23.2% among females. The predominant forms of being bullied were among boys being hit, kicked, pushed, shoved around, or locked indoors and among girls making fun of with sexual jokes, comments, and gestures. Among boys risk factors for having been bullied were younger age (adjusted odds ratio to (AOR): 0.34; 95% confidence interval (CI): 0.18–0.65), having been in a physical fight (AOR: 3.64; 95% CI: 2.84–4.66), being physically inactive (AOR: 1.49; 95% CI: 1.04–2.15), truancy (AOR: 1.66; 95% CI: 1.13–2.45), and psychosocial distress (AOR: 2.07; 95% CI: 1.14–3.74), and among girls risk factors for having been bullied were having been in a physical fight (AOR: 2.91; 95% CI: 2.00–4.24), lack of parental bonding (AOR: 0.71; 95% CI: 0.51–0.99), and psychosocial distress (AOR: 2.37; 95% CI: 1.39–4.03). Results may inform school health programmes on the prevalence and correlates of bullying among adolescents in Thailand.
Artificial Neural Network-Based Fault Distance Locator for Double-Circuit Transmission Lines
Authors: Jain Anamika
Published: February 2013

This paper analyses two different approaches of fault distance location in a double circuit transmission lines, using artificial neural networks. The single and modular artificial neural networks were developed for determining the fault distance location under varying types of faults in both the circuits. The proposed method uses the voltages and currents signals available at only the local end of the line. The model of the example power system is developed using Matlab/Simulink software. Effects of variations in power system parameters, for example, fault inception angle, CT saturation, source strength, its X/R ratios, fault resistance, fault type and distance to fault have been investigated extensively on the performance of the neural network based protection scheme (for all ten faults in both the circuits). Additionally, the effects of network changes: namely, double circuit operation and single circuit operation, have also been considered. Thus, the present work considers the entire range of possible operating conditions, which has not been reported earlier. The comparative results of single and modular neural network indicate that the modular approach gives correct fault location with better accuracy. It is adaptive to variation in power system parameters, network changes and works successfully under a variety of operating conditions.
Massive Deposition and Accumulation of Hydroxyapatite Crystal after Total Hip Arthroplasty: A Case Report
Authors: Yamada Shin , Nozaka Koji , Saito Hidetomo , Kijima Hiroaki , Tazawa Hiroshi , Takasaki Yasusi , Shimada Yoichi
Published: February 2013

We presented a case in which massive hydroxyapatite accumulation was observed around the artificial hip joint. A 66-year-old female showed a massive accumulation of fluid in and around the hip joint, and milk-like aspirate was obtained. Her aspirate culture was negative, and sediment analysis by X-ray diffraction showed that its component was hydroxyapatite. Since pain was mild, the patient was treated conservatively. To our knowledge, this is the first case in which liquid hydroxyapatite (milk of calcium) was accumulated around the artificial hip joint.
Relationship Study on Land Use Spatial Distribution Structure and Energy‐Related Carbon Emission Intensity in Different Land Use Types of Guangdong, China, 1996–2008
Authors: Huang Yi , Xia Bin , Yang Lei
Published: February 2013

This study attempts to discuss the relationship between land use spatial distribution structure and energy‐related carbon emission intensity in Guangdong during 1996–2008. We quantized the spatial distribution structure of five land use types including agricultural land, industrial land, residential and commercial land, traffic land, and other land through applying spatial Lorenz curve and Gini coefficient. Then the corresponding energy‐related carbon emissions in each type of land were calculated in the study period. Through building the reasonable regression models, we found that the concentration degree of industrial land is negatively correlated with carbon emission intensity in the long term, whereas the concentration degree is positively correlated with carbon emission intensity in agricultural land, residential and commercial land, traffic land, and other land. The results also indicate that land use spatial distribution structure affects carbon emission intensity more intensively than energy efficiency and production efficiency do. These conclusions provide valuable reference to develop comprehensive policies for energy conservation and carbon emission reduction in a new perspective.
Heart Transplantation in Congenital Heart Disease: In Whom to Consider and When?
Authors: Attenhofer Jost Christine H. , Schmidt Dörthe , Huebler Michael , Balmer Christian , Noll Georg , Caduff Rosmarie , Greutmann Matthias
Published: February 2013

Due to impressive improvements in surgical repair options, even patients with complex congenital heart disease (CHD) may survive into adulthood and have a high risk of end-stage heart failure. Thus, the number of patients with CHD needing heart transplantation (HTx) has been increasing in the last decades. This paper summarizes the changing etiology of causes of death in heart failure in CHD. The main reasons, contraindications, and risks of heart transplantation in CHD are discussed and underlined with three case vignettes. Compared to HTx in acquired heart disease, HTx in CHD has an increased risk of perioperative death and rejection. However, outcome of HTx for complex CHD has improved over the past 20 years. Additionally, mechanical support options might decrease the waiting list mortality in the future. The number of patients needing heart-lung transplantation (especially for Eisenmenger’s syndrome) has decreased in the last years. Lung transplantation with intracardiac repair of a cardiac defect is another possibility especially for patients with interatrial shunts. Overall, HTx will remain an important treatment option for CHD in the near future.
Removal of a Maxillary Third Molar Displaced into Pterygopalatine Fossa via Intraoral Approach
Authors: Özer Nedim , Üçem Fulya , Saruhanoğlu Alp , Yilmaz Serdar , Tanyeri Hakkı
Published: February 2013

The removal of impacted maxillary third molars is one of the most common procedures performed in oral and maxillofacial surgery units with low rates of complications and morbidity. A few cases of accidental displacement of third molars into adjacent anatomical spaces, such as the infratemporal fossa, the pterygomandibular space, the maxillary sinus, buccal space, or the lateral pharyngeal space, during surgical interventions have been reported. In this paper, a case of a maxillary third molar accidentally displaced into the pterygopalatine fossa is presented, and the removal of the tooth via intraoral approach is described.
A Robust Hybrid Approach Based on Estimation of Distribution Algorithm and Support Vector Machine for Hunting Candidate Disease Genes
Authors: Li Li , Chen Hongmei , Liu Chang , Wang Fang , Zhang Fangfang , Bai Lihua , Chen Yihan , Peng Luying
Published: February 2013

Microarray data are high dimension with high noise ratio and relatively small sample size, which makes it a challenge to use microarray data to identify candidate disease genes. Here, we have presented a hybrid method that combines estimation of distribution algorithm with support vector machine for selection of key feature genes. We have benchmarked the method using the microarray data of both diffuse B cell lymphoma and colon cancer to demonstrate its performance for identifying key features from the profile data of high‐dimension gene expression. The method was compared with a probabilistic model based on genetic algorithm and another hybrid method based on both genetics algorithm and support vector machine. The results showed that the proposed method provides new computational strategy for hunting candidate disease genes from the profile data of disease gene expression. The selected candidate disease genes may help to improve the diagnosis and treatment for diseases.
Wind Speed Forecasting by Wavelet Neural Networks: A Comparative Study
Authors: Yao Chuanan , Gao Xiankun , Yu Yongchang
Published: February 2013

Due to the environmental degradation and depletion of conventional energy, much attention has been devoted to wind energy in many countries. The intermittent nature of wind power has had a great impact on power grid security. Accurate forecasting of wind speed plays a vital role in power system stability. This paper presents a comparison of three wavelet neural networks for short-term forecasting of wind speed. The first two combined models are two types of basic combinations of wavelet transform and neural network, namely, compact wavelet neural network (CWNN) and loose wavelet neural network (LWNN) in this study, and the third model is a new hybrid method based on the CWNN and LWNN models. The efficiency of the combined models has been evaluated by using actual wind speed from two test stations in North China. The results show that the forecasting performances of the CWNN and LWNN models are unstable and are affected by the test stations selected; the third model is far more accurate than the other forecasting models in spite of the drawback of lower computational efficiency.
Information in Repeated Ultimatum Game with Unknown Pie Size
Authors: Lee Ching Chyi , Lau William K.
Published: February 2013

Within existing literature, it is well known that people’s behavior in ultimatum game experiments cannot be explained by perfect rationality model. There is, however, evidence showing that people are boundedly rational. In this paper, we studied repeated ultimatum game experiments in which the pie size is only known to the proposer (player 1), but the transaction history is made known to both players. We found that subject’s behavior can be very well explained by the history-consistent-rationality model (HCR model) of Lee and Ferguson (2010), which suggests that people’s behavior is affected by what they observed in the past. The HCR model is able to yield point predictions whose errors are on average within 5% of the total pie size. The experimental results provide evidence that subjects' behavior is boundedly rational with respect to the transaction history.