bluuebunny/crossref_metadata_2025 huggingface dataset:
-independence for compatible systems of (mod ) representations
Authors: Hui Chun Yin
Published: March 2015

Let$K$be a number field. For any system of semisimple mod $\ell$Galois representations$\{{\it\phi}_{\ell }:\text{Gal}(\bar{\mathbb{Q}}/K)\rightarrow \text{GL}_{N}(\mathbb{F}_{\ell })\}_{\ell }$arising from étale cohomology (Definition 1), there exists a finite normal extension$L$of$K$such that if we denote${\it\phi}_{\ell }(\text{Gal}(\bar{\mathbb{Q}}/K))$and${\it\phi}_{\ell }(\text{Gal}(\bar{\mathbb{Q}}/L))$by$\bar{{\rm\Gamma}}_{\ell }$and$\bar{{\it\gamma}}_{\ell }$, respectively, for all$\ell$and let$\bar{\mathbf{S}}_{\ell }$be the$\mathbb{F}_{\ell }$-semisimple subgroup of$\text{GL}_{N,\mathbb{F}_{\ell }}$associated to$\bar{{\it\gamma}}_{\ell }$(or$\bar{{\rm\Gamma}}_{\ell }$) by Nori’s theory [On subgroups of$\text{GL}_{n}(\mathbb{F}_{p})$, Invent. Math.88(1987), 257–275] for sufficiently large$\ell$, then the following statements hold for all sufficiently large$\ell$.

A(i) The formal character of$\bar{\mathbf{S}}_{\ell }{\hookrightarrow}\text{GL}_{N,\mathbb{F}_{\ell }}$(Definition 1) is independent of$\ell$and equal to the formal character of$(\mathbf{G}_{\ell }^{\circ })^{\text{der}}{\hookrightarrow}\text{GL}_{N,\mathbb{Q}_{\ell }}$, where$(\mathbf{G}_{\ell }^{\circ })^{\text{der}}$is the derived group of the identity component of$\mathbf{G}_{\ell }$, the monodromy group of the corresponding semi-simplified$\ell$-adic Galois representation${\rm\Phi}_{\ell }^{\text{ss}}$.

A(ii) The non-cyclic composition factors of$\bar{{\it\gamma}}_{\ell }$and$\bar{\mathbf{S}}_{\ell }(\mathbb{F}_{\ell })$are identical. Therefore, the composition factors of$\bar{{\it\gamma}}_{\ell }$are finite simple groups of Lie type of characteristic$\ell$and are cyclic groups.

B(i) The total$\ell$-rank$\text{rk}_{\ell }\bar{{\rm\Gamma}}_{\ell }$of$\bar{{\rm\Gamma}}_{\ell }$(Definition 14) is equal to the rank of$\bar{\mathbf{S}}_{\ell }$and is therefore independent of$\ell$.

B(ii) The$A_{n}$-type$\ell$-rank$\text{rk}_{\ell }^{A_{n}}\bar{{\rm\Gamma}}_{\ell }$of$\bar{{\rm\Gamma}}_{\ell }$(Definition 14) for$n\in \mathbb{N}\setminus \{1,2,3,4,5,7,8\}$and the parity of$(\text{rk}_{\ell }^{A_{4}}\bar{{\rm\Gamma}}_{\ell })/4$are independent of$\ell$.
Characterization and Modeling of Microscale Preplaced Powder Cladding Via Fiber Laser
Authors: Paul Santanu , Gupta Ishank , Singh Ramesh K.
Published: March 2015

Laser cladding (LC) is a material deposition technique, in which a laser beam is used to deposit one or several layers of a certain clad material onto a substrate to improve its wear or corrosion resistance. It can also be used for structural repair. Consequently, it is of interest to characterize the residual stresses and the microstructure along with the clad geometry as a function of process parameters. A 100 W fiber laser and focusing optics capable of producing very small spot sizes (∼10 μm) have been integrated with a micromachining center. This paper focuses on providing a comprehensive metallurgical and mechanical characterization of microscale LC of preplaced powdered mixture of cobalt and titanium on IS 2062 (ASTM A36) substrate. Parametric studies were conducted by varying the scanning velocity, laser power, and spot size to produce clad layers well bonded to the substrate. The results show that the width and height of the cladding increases up to 28% and 36%, respectively, due to the variation in the laser parameters. An increase of up to 85% in the microhardness is observed in the cladded layer with presence of Ti–Co intermetallic compounds at the interface, highlighting the application of the process in improving subsurface properties of existing components. The residual stresses obtained in the cladded layer are compressive in nature, indicating the potential application of this technique for repair of structures. In addition, a finite element model has been developed for predicting the clad geometry using a moving Gaussian heat source. Molten region is determined from the thermal model and Tanner's law has been used to account for spreading of the molten layer to accurately predict the clad geometry. The model predicts clad geometry with reasonable prediction errors less than 10% for most cases with stronger dependence on scan velocities in comparison to laser power.
Sensitivity Analysis of Auto-Ignition Simulation at Gas Turbine Operating Conditions
Authors: Prause Juliane , Noll Berthold , Aigner Manfred , Syed Khawar
Published: March 2015

The demand to reduce CO2 emissions favors the use of alternative hydrogen-rich fuels, which can stem from precombustion carbon capture or power-to-gas technologies. These fuels are characterized by a higher reactivity and reduced ignition delay time compared to natural gas. Therefore, current combustor designs need to be adapted to the new requirements. Numerical modeling greatly assists the further development of such systems. The present study aims to determine how far a sophisticated computational fluid dynamics (CFD) combustion method is able to predict auto-ignition at real engine conditions. Scale-resolving computations of auto-ignition were performed at elevated pressure (15 bar) and intermediate temperatures (>1000 K). The conditions are similar to those occurring in premixing ducts of reheat combustors. A nitrogen-diluted hydrogen jet is injected perpendicularly into a stream of hot vitiated air. The scale-adaptive simulation (SAS) method as proposed by Menter and coworkers has been applied. The chemistry is captured by direct inclusion of detailed kinetics. Subgrid fluctuations of temperature and species are considered by an assumed probability density function (PDF) approach. The results are compared with appropriate experimental reference data. The focus of the present work is set on the identification of the major sources of uncertainty in the simulation of auto-ignition. Despite the very challenging operating conditions, satisfactory agreements could be obtained within experimental uncertainties.
Development and Validation of the Multidimensional Motivational Climate Observation System
Authors: Smith Nathan , Tessier Damien , Tzioumakis Yannis , Quested Eleanor , Appleton Paul , Sarrazin Philippe , Papaioannou Athanasios , Duda Joan L.
Published: March 2015

This article outlines the development and validation of the Multidimensional Motivational Climate Observation System (MMCOS). Drawing from an integration of the dimensions of the social environment emphasized within achievement goal theory and self-determination theory (as assumed within Duda’s [2013] conceptualization of “empowering” and “disempowering” climates), the MMCOS was developed to enable an objective assessment of the coach-created motivational environment in sport. Study 1 supported the initial validity and reliability of the newly developed observation system. Study 2 further examined the interobserver reliability and factorial structure of the MMCOS. Study 3 explored the predictive validity of the observational system in relation to athletes’ reported basic psychological need satisfaction. Overall, the results of these studies provide preliminary support for the inter- and intraobserver reliability, as well as factorial and predictive validity of the MMCOS. Suggestions for the use of this observational system in future research in sport are provided.
Gelatin-derived sustainable carbon-based functional materials for energy conversion and storage with controllability of structure and component
Authors: Wang Zhong-Li , Xu Dan , Zhong Hai-Xia , Wang Jun , Meng Fan-Lu , Zhang Xin-Bo
Published: March 2015

This synthetic approach produced catalysts with higher catalytic activity and better oxygen-reduction durability.
Identification of different oxygen species in oxide nanostructures with
17
O solid-state NMR spectroscopy
Authors: Wang Meng , Wu Xin-Ping , Zheng Sujuan , Zhao Li , Li Lei , Shen Li , Gao Yuxian , Xue Nianhua , Guo Xuefeng , Huang Weixin , Gan Zhehong , Blanc Frédéric , Yu Zhiwu , Ke Xiaokang , Ding Weiping , Gong Xue-Qing , Grey Clare P. , Peng Luming
Published: March 2015

Nanostructured oxides find multiple uses in a diverse range of applications including catalysis, energy storage, and environmental management, their higher surface areas, and, in some cases, electronic properties resulting in different physical properties from their bulk counterparts. Developing structure-property relations for these materials requires a determination of surface and subsurface structure. Although microscopy plays a critical role owing to the fact that the volumes sampled by such techniques may not be representative of the whole sample, complementary characterization methods are urgently required. We develop a simple nuclear magnetic resonance (NMR) strategy to detect the first few layers of a nanomaterial, demonstrating the approach with technologically relevant ceria nanoparticles. We show that the
17
O resonances arising from the first to third surface layer oxygen ions, hydroxyl sites, and oxygen species near vacancies can be distinguished from the oxygen ions in the bulk, with higher-frequency
17
O chemical shifts being observed for the lower coordinated surface sites. H
2
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O can be used to selectively enrich surface sites, allowing only these particular active sites to be monitored in a chemical process.
17
O NMR spectra of thermally treated nanosized ceria clearly show how different oxygen species interconvert at elevated temperature. Density functional theory calculations confirm the assignments and reveal a strong dependence of chemical shift on the nature of the surface. These results open up new strategies for characterizing nanostructured oxides and their applications.
Geniposide protects against acute alcohol-induced liver injury in mice via up-regulating the expression of the main antioxidant enzymes
Authors: Wang Junming , Zhang Yueyue , Liu Ruixin , Li Xiaobing , Cui Ying , Qu Lingbo
Published: March 2015

Geniposide (GP) is one of main compounds in Gardenia jasminoides Ellis, with both medicinal and nutritional value. This study was designed to determine, for the first time, how GP from G. jasminoides protects against acute alcohol-induced liver injury, and the underlying mechanisms. Mice were orally administered alcohol (6.0 g/kg body mass) 2 h after intragastric administration of GP and bifendate, every day for 7 continuous days. Six hours after the alcohol was administered, levels of serum alanine/aspartate transaminase (ALT/AST), hepatic lipid peroxidation (LPO), glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxidase (GPx), copper- and zinc-containing superoxide dismutase (CuZn-SOD), and catalase (CAT), and mRNA expression of CuZn-SOD and CAT were assayed. The results demonstrated that GP (20.0, 40.0, or 80 mg/kg) significantly reversed the excessive, alcohol-induced elevation in both serum ALT/AST and hepatic LPO levels. Moreover, hepatic GSH, GST, GPx, CuZn-SOD, and CAT levels were all decreased in the alcohol-treated mice, whereas treatment with GP reversed these decreases. Further analysis indicated that hepatic mRNA expression of CuZn-SOD and CAT in the alcohol-treated mice was significantly down-regulated, whereas GP up-regulated such decreases. Taken together, this study shows that GP protects against acute alcohol-induced liver injury via up-regulating the expression of the main antioxidant enzymes, and thus ameliorates alcohol-induced oxidative stress injury in the liver.
Scaling in fracture mechanics by Bažant law: From finite to linearized elasticity
Authors: Negri Matteo , Toader Rodica
Published: March 2015

We consider crack propagation in brittle nonlinear elastic materials in the context of quasi-static evolutions of energetic type. Given a sequence of self-similar domains nΩ on which the imposed boundary conditions scale according to Bažant's law, we show, in agreement with several experimental data, that the corresponding sequence of evolutions converges (for n → ∞) to the evolution of a crack in a brittle linear-elastic material.
Active Visual Perception for Humanoid Robots
Authors: Martín Francisco , Agüero Carlos E. , Cañas José M.
Published: March 2015

Robots detect and keep track of relevant objects in their environment to accomplish some tasks. Many of them are equipped with mobile cameras as the main sensors, process the images and maintain an internal representation of the detected objects. We propose a novel active visual memory that moves the camera to detect objects in robot's surroundings and tracks their positions. This visual memory is based on a combination of multi-modal filters that efficiently integrates partial information. The visual attention subsystem is distributed among the software components in charge of detecting relevant objects. We demonstrate the efficiency and robustness of this perception system in a real humanoid robot participating in the RoboCup SPL competition.
Non-Abelian gauge redundancy and entropic ambiguities
Authors: Balachandran A. P. , de Queiroz A. R. , Vaidya S.
Published: March 2015

The von Neumann entropy of a generic quantum state is not unique unless the state can be uniquely decomposed as a sum of extremal or pure states. Therefore one reaches the remarkable possibility that there may be many entropies for a given state. We show that this happens if the GNS representation (of the algebra of observables in some quantum state) is reducible, and some representations in the decomposition occur with non-trivial degeneracy. This ambiguity in entropy, which can occur at zero temperature, can often be traced to a gauge symmetry emergent from the non-trivial topological character of the configuration space of the underlying system. We also establish the analogue of an H-theorem for this entropy by showing that its evolution is Markovian, determined by a stochastic matrix. After demonstrating this entropy ambiguity for the simple example of the algebra of 2 × 2 matrices, we argue that the degeneracies in the GNS representation can be interpreted as an emergent broken gauge symmetry, and play an important role in the analysis of emergent entropy due to non-Abelian anomalies. We work out the simplest situation with such non-Abelian symmetry, that of an ethylene molecule.
Structure of MnOx/TiO2 Catalysts and Their Catalytic Performance in the Gas-Phase Oxidation of o-Dichlorobenzene
Authors: Zhang Wenrui , Tang Aidong , Ren Dabin , Xiang Hui , Yu Zhiqiang , Sheng Guoying , Fu Jiamo
Published: March 2015

The influence of structure of MnO x/ TiO 2 catalysts and their catalytic oxidation of o-dichlorobenzene were examined in this study. MnO x/ TiO 2 catalysts were characterized by X-ray diffractometer (XRD), thermogravimetry-differential thermal analysis (TG-DTA), TEM, X-ray photoelectron spectrum (XPS) and FTIR for NH 3 adsorption techniques. Experimental results indicated that the MnO x/ TiO 2 catalyst prepared from manganese nitrate possessed the highest catalytic activity with a gas hourly space velocity (GHSV) of 14,500 h-1. This activity may be due to a large amount of surface Mn 2 O 3 species, the strong Brönsted and Lewis acidity and the combined TiO 2 phases. Additionally, a possible reaction model from o-dichlorobenzene oxidation over MnO x/ TiO 2 catalyst was suggested based on the analysis.
Graphene/Carbon Nanotubes Hybrid Electrode Material for High Performance Supercapacitor
Authors: Wang Yongzhen , Wang Yong , Liu Yuyu , Ohuchi Azuma , Wang Xiaomin
Published: March 2015

A graphene (GN)/carbon nanotubes (CNTs) nanocomposite electrode material were prepared via reduction of exfoliated graphite oxides in the presence of CNTs pretreated by mixed acid. The GN/CNTs nanocomposite characterized by X-ray diffraction (XRD), Raman spectrum (Raman) and scanning electron microscope (SEM) has a layered structure with CNTs uniformly sandwiched between the GN sheets, which efficiently decreased the agglomeration GN sheets. Electrochemical data demonstrate that the GN/CNT exhibited higher specific capacitance than that of graphene.
Quaternion-Based Improved Artificial Bee Colony Algorithm for Color Remote Sensing Image Edge Detection
Authors: Liu Dujin , Wang Huajun , Wang Sen , Pu Guolin , Deng Xiaoya , Hou Xiang
Published: March 2015

As the color remote sensing image has the most notable features such as huge amount of data, rich image details, and the containing of too much noise, the edge detection becomes a grave challenge in processing of remote sensing image data. To explore a possible solution to the urgent problem, in this paper, we first introduced the quaternion into the representation of color image. In this way, a color can be represented and analyzed as a single entity. Then a novel artificial bee colony method named improved artificial bee colony which can improve the performance of conventional artificial bee colony was proposed. In this method, in order to balance the exploration and the exploitation, two new search equations were presented to generate candidate solutions in the employed bee phase and the onlookers phase, respectively. Additionally, some more reasonable artificial bee colony parameters were proposed to improve the performance of the artificial bee colony. Then we applied the proposed method to the quaternion vectors to perform the edge detection of color remote sensing image. Experimental results show that our method can get a better edge detection effect than other methods.
On the Lightning Electromagnetic Fields due to Channel with Variable Return Stroke Velocity
Authors: Izadi M. , Ab Kadir M. Z. A. , Hajikhani M.
Published: March 2015

Numerical field expressions are proposed to evaluate the electromagnetic fields due to the lightning channel with variable values of return stroke velocity. Previous calculation methods generally use an average value for the return stroke velocity along a lightning channel. The proposed method can support different velocity profiles along a lightning channel in addition to the widely used channel-base current functions and also the general form of the engineering current models directly in the time domain without the need to apply any extra conversions. Moreover, a sample of the measured lightning current is used to validate the proposed method while the velocity profile is simulated by the general velocity function. The simulated fields based on constant and variable values of velocity are compared to the corresponding measured fields. The results show that the simulated fields based on the proposed method are in good agreement with the corresponding measured fields.
Modified Theories of Gravitation behind the Spacetime Deformation
Authors: Ter-Kazarian Gagik
Published: March 2015

In the framework of proposed theory of spacetime deformation/distortion, we have a way to deform the spacetime through a nontrivial choice of the distortion-complex, displaying different connections, which may reveal different post-Riemannian spacetime structures as corollary. We extend this theory to address, in particular, the gauge model of the most general metric-affine gravity carrying both nontrivial torsion and nonmetricity. This model is constructed in the framework of the first order Lagrangian expressed in terms of the gauge potentials and their first derivatives. The equations of the standard theory, which have no propagating modes for torsion, can be equivalently replaced in modified framework by the modified equations, which in the limit of reducing the affine group leads to the modified Einstein-Cartan theory with dynamical torsion and beyond. In testing the modified framework for various particular cases, we use the Lagrange multipliers for extinguishing nonmetricity and torsion.
An Online Distributed Game Optimal Control for Heavy Haul Trains with Limited Communication
Authors: Gao Kai , Huang Zhiwu , Peng Jun , Li Heng , Liu Weirong
Published: March 2015

For heavy haul trains, it is difficult to get global information due to the limited range of communication. This paper proposed a novel distributed optimal control based on game strategy, in which the global optimization is achieved by equilibrizing subsystems’ performance just utilizing local information. To online solve the game control, an efficient multivariable extremum seeking algorithm was adapted to approximate the partial differential equation deduced by optimal condition. The convergence of the proposed approximate algorithm is proved by constructing a fictitious Lie bracket system using Lyapunov function. Finally, the proposed distributed optimal control is valuated rigorously by case study according to the configuration of Daqin railway in China.
Acute Dysphasia and Reversible Cognitive Decline in a Patient with Probable Cerebral Amyloid Angiopathy-Related Inflammation
Authors: Rigney Louise , Sebire Dale , Cordato Dennis
Published: March 2015

Cerebral amyloid angiopathy related inflammation (CAAri) is becoming increasingly recognised as a subset of cerebral amyloid angiopathy (CAA). CAAri generally presents with subacute cognitive decline, headaches, seizures, behavioral changes, and focal neurological deficits. We describe a patient who developed acute dysphasia and reversible cognitive decline due to probable CAAri. CT brain showed bilateral vasogenic edema in the cerebral hemispheres, predominantly involving the parietal and temporal lobes, left greater than right without enhancement. Magnetic resonance brain imaging showed extensive multifocal areas of subcortical white matter T2 hyperintensity in the frontal and temporal regions with associated mass effect, negligible enhancement, and multiple foci of microhemorrhage on susceptibility weighted imaging sequences consistent with a diagnosis of probable CAAri. She responded dramatically to a course of intravenous methylprednisolone followed by further immunosuppression with pulse intravenous cyclophosphamide. Her dysphasia resolved within 5 days of intravenous methylprednisolone therapy. Her MMSE improved from 11/30 at day 5 of admission to 28/30 at 6-month follow-up. The notable features of our case were the unusual CT findings, which were inconsistent with stroke and diagnostic utility of susceptibility-weighted magnetic resonance imaging in confirming the diagnosis which allowed for prompt institution of immunosuppression.
An Efficient Iterative Scheme Using Family of Chebyshev’s Operations
Authors: Mahdavi Seyed Hossein , Abdul Razak Hashim
Published: March 2015

This paper presents an efficient iterative method originated from the family of Chebyshev’s operations for the solution of nonlinear problems. For this aim, the product operation matrix of integration is presented, and therefore the operation of derivative is developed by using Chebyshev wavelet functions of the first and second kind, initially. Later, Chebyshev’s iterative method is improved by approximation of the first and second derivatives. The analysis of convergence demonstrates that the method is at least fourth-order convergent. The effectiveness of the proposed scheme is numerically and practically evaluated. It is concluded that it requires the less number of iterations and lies on the best performance of the proposed method, especially for highly varying nonlinear problems.
The Coupling Characteristic Investigation of Double-Gimbal Magnetically Suspended Control Moment Gyro Used on Agile Maneuver Spacecraft
Authors: Cui Peiling , Cui Jian , Yang Qian , Zheng Shiqiang
Published: March 2015

Double-gimbal magnetically suspended CMG is a novel attitude control actuator for the agile maneuver spacecraft. Taking the double-gimbal magnetically suspended control moment gyro used on agile maneuver spacecraft as the research object, the dynamic model of the magnetically suspended rotor, the inner gimbal, and the outer gimbal of double-gimbal magnetically suspended control moment gyro is built. The nonlinear coupling characteristic between the rotor, the gimbal, and the spacecraft is given. It can be seen that the motion of magnetically suspended rotor does not only rely on magnetic bearing force but also suffer from the influence of gimbal servo system and spacecraft motion. The coupling torque includes the gyro coupling torque and the inertial coupling torque. The work in this paper provides the foundation for further studies.
Concept of Bee-Eyes Array of Fresnel Lenses as a Solar Photovoltaic Concentrator System
Authors: Chiromawa Nura Liman , Ibrahim Kamarulazizi
Published: March 2015

This paper presents a proposal of a new configuration of an optical concentrator for photovoltaic application which may enhance the efficiency of solar cells. Bee-eyes array Fresnel lenses concentrator proposed here provide high concentration factor which is greater than1000x at the 20th zone. In addition, the system also provides room for increasing the number of zones to achieve the high concentration factor if needs arise. The transmission efficiency greater than 90% has been achieved with f-number of ≥1.25. Mathematical relations derived to obtain flux distribution at the absorber plane and the transmission efficiency as well as the position of the solar cell were used in the ray tracing simulations for 6, 18, 36, 60, 90, 126, 168, 216, 270, and 330 suns concentration systems. A transmission efficiency is linearly decreasing with the increase in the number of arrays in which the transmission efficiency of 94.42% was recorded at the array of 6 suns and 74.98% at 330 suns.
Accuracy, Robustness, and Efficiency of the Linear Boundary Condition for the Black-Scholes Equations
Authors: Jeong Darae , Seo Seungsuk , Hwang Hyeongseok , Lee Dongsun , Choi Yongho , Kim Junseok
Published: March 2015

We briefly review and investigate the performance of various boundary conditions such as Dirichlet, Neumann, linear, and partial differential equation boundary conditions for the numerical solutions of the Black-Scholes partial differential equation. We use a finite difference method to numerically solve the equation. To show the efficiency of the given boundary condition, several numerical examples are presented. In numerical test, we investigate the effect of the domain sizes and compare the effect of various boundary conditions with pointwise error and root mean square error. Numerical results show that linear boundary condition is accurate and efficient among the other boundary conditions.
H∞Control for Nonlinear Stochastic Systems with Time-Delay and Multiplicative Noise
Authors: Gao Ming , Zhang Weihai , Zhu Zhengmao
Published: March 2015

This paper studies the infinite horizonH∞control problem for a general class of nonlinear stochastic systems with time-delay and multiplicative noise. The exponential/asymptotic mean squareH∞control design of delayed nonlinear stochastic systems is presented by solving Hamilton-Jacobi inequalities. Two numerical examples are provided to show the effectiveness of the proposed design method.
Connectivity Study of the Neuromechanism of Acute Acupuncture Needling during fMRI in “Overweight” Subjects
Authors: von Deneen Karen M. , Qin Wei , Liu Peng , Dong Minghao , Chen Peng , Xie Huisheng , Zhang Yi , Gold Mark S. , Liu Yijun , Tian Jie
Published: March 2015

This functional connectivity study depicts how acupoints ST 36 and SP 9 and their sham acupoints acutely act on blood glucose (GLU), core body temperature (CBT), hunger, and sensations pertaining to needling (De-qi) via the limbic system and dopamine (DA) to affect various brain areas in fasting, adult, and “overweight” Chinese males using functional magnetic resonance imaging. Functional connectivity (FC) analysis utilized the amygdala (AMY) and hypothalamus (HYP) as regions of interest (ROIs) in the discrete cosine transform and seed correlation analysis methods. There was a significant difference in the spatial patterns of the distinct brain regions between groups. Correlation results showed that increased HYP-hippocampus FC after ACU was positively correlated with ACU-induced change in CBT; increased HYP-putamen-insula FC after ACU was positively correlated with ACU-induced change in GLU; and increased HYP-anterior cingulate cortex FC after ACU was positively correlated with ACU-induced change in HUNGER suggesting that increased DA modulation during ACU was probably associated with increased poststimulation limbic system and spinothalamic tract connectivity. Decreased HYP-thalamus FC after ACU was negatively correlated or anticorrelated with ACU-induced change in HUNGER suggesting that increased DA modulation during ACU was possibly associated with decreased poststimulation limbic system and spinothalamic tract connectivity. No correlation was found for min SHAM. This was an important study in addressing acute acupuncture effects and neural pathways involving physiology and appetite regulation in overweight individuals.
Improved Emotion Recognition Using Gaussian Mixture Model and Extreme Learning Machine in Speech and Glottal Signals
Authors: Muthusamy Hariharan , Polat Kemal , Yaacob Sazali
Published: March 2015

Recently, researchers have paid escalating attention to studying the emotional state of an individual from his/her speech signals as the speech signal is the fastest and the most natural method of communication between individuals. In this work, new feature enhancement using Gaussian mixture model (GMM) was proposed to enhance the discriminatory power of the features extracted from speech and glottal signals. Three different emotional speech databases were utilized to gauge the proposed methods. Extreme learning machine (ELM) andk-nearest neighbor (kNN) classifier were employed to classify the different types of emotions. Several experiments were conducted and results show that the proposed methods significantly improved the speech emotion recognition performance compared to research works published in the literature.
Prevalence of and Risk Factors for Lipoatrophy in Patients with HIV Infection in Nigeria
Authors: Iwuala Sandra Omozehio , Lesi Olufunmilayo A. , Fasanmade Olufemi Adetola , Sabir Anas A. , Olamoyegun Michael Adeyemi , Okany Charles C.
Published: March 2015

Background. Although the association between lipoatrophy and highly active antiretroviral therapy (HAART) is well known, other nondrug factors may be associated with lipoatrophy in people living with HIV/AIDS (PLWHA). There are no reports of lipoatrophy from Nigeria, a country with the second largest number of PLWHA. We aimed to determine the prevalence, characteristics, and factors associated with lipoatrophy in a cohort of patients attending the HIV clinic in Lagos University Teaching Hospital, Nigeria.Methods. Two hundred and eighty-eight patients with HIV infection were recruited for the study. The study protocol involved administration of a questionnaire, targeted physical examination (including anthropometric indices and skin fold thickness), and bioelectrical impedance analysis measurements. Lipoatrophy was defined clinically.Results. Lipoatrophy was present in 75 (26.0%) persons. It was associated with lower body circumferences, skin fold thicknesses, and lower % body fat with preservation of skeletal muscle mass (allP<0.05). Male gender and HAART use were the factors associated with lipoatrophy on multivariate analysis(P<0.05).Conclusion. Lipoatrophy is frequently encountered in patients with HIV infection in Nigeria, with HAART use conferring an added factor in its development. There is need for more physician and patient awareness of this condition.
Identification of Premature Ventricular Cycles of Electrocardiogram Using Discrete Cosine Transform-Teager Energy Operator Model
Authors: Sharmila Vallem , Reddy K. Ashoka
Published: March 2015

An algorithm based on the ability of TEO to track the changes in the envelope of ECG signal is proposed for identifying PVCs in ECG. Teager energy is calculated from DCT coefficients of ECG signal. This method can be considered as computationally efficient algorithm when compared with the well-known DCT cepstrum technique. EPE is derived from the teager energy of DCT coefficients in DCT-TEO method and from the cepstrum of DCT coefficients in the existing method. EPE determines the decay rate of the action potential of ECG beat and provides sufficient information to identify the PVC beats in ECG data. EPEs obtained by DCT-TEO and existing DCT cepstrum models are compared. The proposed algorithm has resulted in performance measures like sensitivity of 98–100%, positive predictivity of 100%, and detection error rate of 0.03%, when tested on MIT-BIH database signals consisting of PVC and normal beats. Result analysis reveals that the DCT-TEO algorithm worked well in clear identification of PVCs from normal beats compared to the existing algorithm, even in the presence of artifacts like baseline wander, PLI, and noise with SNR of up to −5 dB.
Possible Involvement ofµOpioid Receptor in the Antidepressant-Like Effect of Shuyu Formula in Restraint Stress-Induced Depression-Like Rats
Authors: Wang Fu-rong , Qiao Ming-qi , Xue Ling , Wei Sheng
Published: March 2015

Recentlyμopioid receptor (MOR) has been shown to be closely associated with depression. Here we investigated the action of Shuyu, a Chinese herbal prescription, on repeated restraint stress induced depression-like rats, with specific attention to the role of MOR and the related signal cascade. Our results showed that repeated restraint stress caused significant depressive-like behaviors, as evidenced by reduced body weight gain, prolonged duration of immobility in forced swimming test, and decreased number of square-crossings and rearings in open field test. The stress-induced depression-like behaviors were relieved by Shuyu, which was accompanied by decreased expression of MOR in hippocampus. Furthermore, Shuyu upregulated BDNF protein expression, restored the activity of CREB, and stimulated MEK and ERK phosphorylation in hippocampus of stressed rats. More importantly, MOR is involved in the effects of Shuyu on these depression-related signals, as they can be strengthened by MOR antagonist CTAP. Collectively, these data indicated that the antidepressant-like properties of Shuyu are associated with MOR and the corresponding CREB, BDNF, MEK, and ERK signal pathway. Our study supports clinical use of Shuyu as an effective treatment of depression and also suggests that MOR might be a target for treatment of depression and developing novel antidepressants.
QoS Analysis for a Nonpreemptive Continuous Monitoring and Event-Driven WSN Protocol in Mobile Environments
Authors: Leyva-Mayorga Israel , Rivero-Angeles Mario E. , Carreto-Arellano Chadwick , Pla Vicent
Published: March 2015

Evolution in wireless sensor networks (WSNs) has allowed the introduction of new applications with increased complexity regarding communication protocols, which have to ensure that certain QoS parameters are met. Specifically, mobile applications require the system to respond in a certain manner in order to adequately track the target object. Hybrid algorithms that perform Continuous Monitoring (CntM) and Event-Driven (ED) duties have proven their ability to enhance performance in different environments, where emergency alarms are required. In this paper, several types of environments are studied using mathematical models and simulations, for evaluating the performance of WALTER, a priority-based nonpreemptive hybrid WSN protocol that aims to reduce delay and packet loss probability in time-critical packets. First, randomly distributed events are considered. This environment can be used to model a wide variety of physical phenomena, for which report delay and energy consumption are analyzed by means of Markov models. Then, mobile-only environments are studied for object tracking purposes. Here, some of the parameters that determine the performance of the system are identified. Finally, an environment containing mobile objects and randomly distributed events is considered. It is shown that by assigning high priority to time-critical packets, report delay is reduced and network performance is enhanced.
Dynamic Instability Analysis of a Rotating Ship Shaft under a Periodic Axial Force by Discrete Singular Convolution
Authors: Li Wei , Song Zhiwei , Gao Xuexia , Chen Zhigang
Published: March 2015

Dynamic instability of a rotating ship shaft subjected to a periodic axial force is studied by using discrete singular convolution (DSC) with regularized Shannon’s delta kernel. The excitation frequency is related to the spinning speed and the number of blades on the propeller. Effects of number of blades, constant term in the periodic force, and damping on dynamic instability regions are investigated. The results have shown that the increase of number of blades and damping could improve the dynamic stability of rotating shaft with damping. The increase of constant term in the periodic force leads to dynamic instability regions shifting to lower frequencies, making the shaft more sensitive to periodic force. Those dynamic instability regions obtained by DSC method have been compared with those by Floquet’s method to verify the application of DSC method to dynamic instability analysis of rotating ship shaft.
Mapping Orbits regarding Perturbations due to the Gravitational Field of a Cube
Authors: Venditti Flaviane C. F. , Prado Antonio F. B. A.
Published: March 2015

The orbital dynamics around irregular shaped bodies is an actual topic in astrodynamics, because celestial bodies are not perfect spheres. When it comes to small celestial bodies, like asteroids and comets, it is even more import to consider the nonspherical shape. The gravitational field around them may generate trajectories that are different from Keplerian orbits. Modeling an irregular body can be a hard task, especially because it is difficult to know the exact shape when observing it from the Earth, due to their small sizes and long distances. Some asteroids have been observed, but it is still a small amount compared to all existing asteroids in the Solar System. An approximation of their shape can be made as a sum of several known geometric shapes. Some three-dimensional figures have closed equations for the potential and, in this work, the formulation of a cube is considered. The results give the mappings showing the orbits that are less perturbed and then have a good potential to be used by spacecrafts that need to minimize station-keeping maneuvers. Points in the orbit that minimizes the perturbations are found and they can be used for constellations of nanosatellites.
Catalpol Modulates Lifespan via DAF-16/FOXO and SKN-1/Nrf2 Activation inCaenorhabditis elegans
Authors: Seo Hyun Won , Cheon Se Myung , Lee Myon-Hee , Kim Hong Jun , Jeon Hoon , Cha Dong Seok
Published: March 2015

Catalpol is an effective component of rehmannia root and known to possess various pharmacological properties. The present study was aimed at investigating the potential effects of catalpol on the lifespan and stress tolerance usingC. elegansmodel system. Herein, catalpol showed potent lifespan extension of wild-type nematode under normal culture condition. In addition, survival rate of catalpol-fed nematodes was significantly elevated compared to untreated control under heat and oxidative stress but not under hyperosmolality conditions. We also found that elevated antioxidant enzyme activities and expressions of stress resistance proteins were attributed to catalpol-mediated increased stress tolerance of nematode. We further investigated whether catalpol’s longevity effect is related to aging-related factors including reproduction, food intake, and growth. Interestingly, catalpol exposure could attenuate pharyngeal pumping rate, indicating that catalpol may induce dietary restriction of nematode. Moreover, locomotory ability of aged nematode was significantly improved by catalpol treatment, while lipofuscin levels were attenuated, suggesting that catalpol may affect age-associated changes of nematode. Our mechanistic studies revealed thatmek-1, daf-2, age-1, daf-16, andskn-1are involved in catalpol-mediated longevity. These results indicate that catalpol extends lifespan and increases stress tolerance ofC. elegansvia DAF-16/FOXO and SKN-1/Nrf activation dependent on insulin/IGF signaling and JNK signaling.
Improvement of High-Power Three-Level Explosion-Proof Inverters Using Soft Switching Control Based on Optimized Power-Loss Algorithm
Authors: Xu Shi-Zhou , He Feng-You
Published: March 2015

The high-power three-level explosion-proof inverters demand high thermal stability of power devices, and a set of theories and methods is needed to achieve an accurate power-loss calculation of power devices, to establish heat dissipation model, and ultimately to reduce the power loss to improve thermal stability of system. In this paper, the principle of neutral point clamped three-level (NPC3L) inverter is elaborated firstly, and a fourth-order RC equivalent circuit of IGBT is derived, on which basis the power-loss model of IGBT and the optimized maternal power-loss thermal model, using an optimized power-loss algorithm, are established. Secondly, in accordance with the optimized maternal power-loss thermal model, the generic formulas of power-loss calculation are deduced to calculate the power-loss modification values of NPC3L and soft switching three-level (S3L) inverters, which will be the thermal sources during thermal analysis for maternal power-loss thermal models. Finally, the experiment conducted on the 2.1 MW experimental platform shows that S3L inverter has the same excellent output characteristics with NPC3L inverter, reduces the power loss significantly by 213 W in each half-bridge, and decreases the temperature by 10°C, coinciding with the theoretical calculation, which verifies the accuracy of optimized power-loss algorithm and the effectiveness of the improvement.
Locomotive Assignment Problem with Heterogeneous Vehicle Fleet and Hiring External Locomotives
Authors: Teichmann Dušan , Dorda Michal , Golc Karel , Bínová Helena
Published: March 2015

This paper focuses on solving the problem of how to assign locomotives to assembled trains optimally. To solve the problem, linear programming is applied. The situation we model in the paper occurs in the conditions of a transport operator that provides rail transport in the Czech Republic. In the paper, an extended locomotive assignment problem is modeled; the transport operator can use different classes of the locomotives to serve individual connections, some connections must be served by a predefined locomotive class, and the locomotives can be allocated to several depots at the beginning. The proposed model also takes into consideration the fact that some connections can be served by the locomotives of external transport companies or operators. The presented model is applied to a real example in order to test its functionality.
Malignant Pleural Mesothelioma Outcomes in the Era of Combined Platinum and Folate Antimetabolite Chemotherapy
Authors: Saint-Pierre Mathieu D. , Pease Christopher , Mithoowani Hamid , Zhang Tinghua , Nicholas Garth A. , Laurie Scott A. , Wheatley-Price Paul
Published: March 2015

Introduction. Malignant pleural mesothelioma (MPM) is associated with a poor prognosis. Palliative platinum-based chemotherapy may help to improve symptoms and prolong life. Since 2004, the platinum is commonly partnered with a folate antimetabolite. We performed a review investigating if survival had significantly changed before and after the arrival of folate antimetabolites in clinical practice. Methods. All MPM patients from January 1991 to June 2012 were identified. Data collected included age, gender, asbestos exposure, presenting signs/symptoms, performance status, histology, stage, bloodwork, treatment modalities including chemotherapy, and date of death or last follow-up. The primary endpoint was overall survival. Cox models were applied to determine variables associated with survival. Results. There were 245 patients identified. Median overall survival for all patients was 9.4 months. After multivariate analysis, performance status, stage, histology, leucocytosis, and thrombophilia remained independently associated with survival. Among all patients who received chemotherapy, there was no difference in overall survival between the periods before and after folate antimetabolite approval: 14.2 versus 13.2 months (P=0.35). Specifically receiving combined platinum-based/folate antimetabolite chemotherapy did not improve overall survival compared to all other chemotherapy regimens: 14.1 versus 13.6 months (P=0.97). Conclusions. In this review, we did not observe an incremental improvement in overall survival after folate antimetabolites became available.
Clinical Applications of Anterior Segment Optical Coherence Tomography
Authors: Lim Su-Ho
Published: March 2015

Anterior segment optical coherence tomography (AS-OCT) was recently developed and has become a crucial tool in clinical practice. AS-OCT is a noncontact imaging device that provides the detailed structure of the anterior part of the eyes. In this review, the author will discuss the various clinical applications of AS-OCT, such as the normal findings, tear meniscus measurement, ocular surface disease (e.g., pterygium, pinguecula, and scleromalacia), architectural analysis after cataract surgery, post-LASIK keratectasia, Descemet’s membrane detachment, evaluation of corneal graft after keratoplasty, corneal deposits (corneal dystrophies and corneal verticillata), keratitis, anterior segment tumors, and glaucoma evaluation (angle assessment, morphological analysis of the filtering bleb after trabeculectomy, or glaucoma drainage device implantation surgery). The author also presents some interesting cases demonstrated via AS-OCT.
Systems and Algorithms for Wireless Sensor Networks Based on Animal and Natural Behavior
Authors: Sendra Sandra , Parra Lorena , Lloret Jaime , Khan Shafiullah
Published: March 2015

In last decade, there have been many research works about wireless sensor networks (WSNs) focused on improving the network performance as well as increasing the energy efficiency and communications effectiveness. Many of these new mechanisms have been implemented using the behaviors of certain animals, such as ants, bees, or schools of fish. These systems are called bioinspired systems and are used to improve aspects such as handling large-scale networks, provide dynamic nature, and avoid resource constraints, heterogeneity, unattended operation, or robustness, among many others. Therefore, this paper aims to study bioinspired mechanisms in the field of WSN, providing the concepts of these behavior patterns in which these new approaches are based. The paper will explain existing bioinspired systems in WSNs and analyze their impact on WSNs and their evolution. In addition, we will conduct a comprehensive review of recently proposed bioinspired systems, protocols, and mechanisms. Finally, this paper will try to analyze the applications of each bioinspired mechanism as a function of the imitated animal and the deployed application. Although this research area is considered an area with highly theoretical content, we intend to show the great impact that it is generating from the practical perspective.
Evaluation of Differences between PaCO2 and ETCO2 by Age as Measured during General Anesthesia with Patients in a Supine Position
Authors: Satoh Kenichi , Ohashi Ayako , Kumagai Miho , Sato Masahito , Kuji Akiyoshi , Joh Shigeharu
Published: March 2015

Objective. The aim of this study was to evaluate the arterial to end-tidal partial pressure gradient of carbon dioxide according to age in the supine position during general anesthesia. Methods. From January 2001 to December 2013, we evaluated 596 patients aged ≥16 years who underwent general anesthesia in the supine position. The anesthetic charts of these 596 patients, all classified as American Society of Anesthesiologists physical status I or II, were retrospectively reviewed to investigate the accuracy of PaCO2 and ETCO2. Results. The a-ETCO2 was 3.0 ± 2.1 mmHg for patients aged 16 to <65 years and 4.1±3.1 mmHg for patients ≥65 years. The a-ETCO2 was 2.4±3.1 mmHg for patients aged 16 to 25 years, 3.1±2.2 mmHg for patients aged 26 to 35 years, 3.0±2.2 mmHg for patients aged 36 to 45 years, 3.4±2.0 mmHg for patients aged 46 to 55 years, 3.2±2.0 mmHg for patients aged 56 to 64 years, 4.3±3.2 mmHg for patients aged 65 to 74 years, and 3.7±2.8 mmHg for patients aged 75 to 84 years. Conclusion. The arterial to end-tidal partial pressure gradient of carbon dioxide tended to increase with increasing age.