bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Manufacturing Techniques Subject to High Speed Impact
Authors: Gollins Kenneth , Chiu Jack , Delale Feridun , Liaw Benjamin , Gursel Ali
Published: February 2016

In this paper we compare two manufacturing techniques namely vacuum infusion and compression molding, used in manufacturing S2 glass fabric/epoxy composites for high-speed impact applications. Even though compression molding and vacuum infusion are two widely used manufacturing techniques, the resulting product may be very different. Compression molding has the advantage of achieving a much higher fiber density for the same thickness. With a higher fiber density, the composites made by compression molding have better mechanical properties than a composite made by vacuum infusion. However, vacuum infusion is faster and more economical. The mechanical performance of the composites manufactured by these two processes are compared by performing tensile tests and high speed impact tests for the determination of the limit speed V50. For the same number of plies, preliminary results for compression molded specimens indicate a 50% increase in stiffness and a 40% increase in strength. Also, for panels of the same thickness, the V50 was higher for compression molding specimens.
Strain and Damage Sensing of CNT-Epoxy Composite via Electrical Conductivity
Authors: Ardebili Mahmoud K. , Ikikardaslar Kerim T. , Delale Feridun
Published: February 2016

Self-sensing via piezoresistivity of multiwall carbon nanotube-epoxy resin composite was studied in order to assess its feasibility in strain and damage detection. Self-sensing is an economical and durable component of Structural Health Monitoring of manufactured composite, in which the material is employed as sensor. Objective of the study centered on strain and damage sensing and particularly focused on how applied tension and /or inflicted damage affected electrical conductivity. The MWCNT-epoxy composite was manufactured with non-treated multiwall carbon-nanotubes. They were dispersed in the epoxy employing ultrasonic dispersion and mechanical mixing, prior to addition of curing agent. The samples were rectangular specimen of dimensions 150 mm × 25 mm × 5 mm. Surface electrodes were created with sliver paint, to which copper wire leads were wrapped and affixed with more silver paint or carbon based electrically conductive glue. Kelvin in-line resistivity measurement technique was adopted to assess and monitor composite resistivity. The technique minimizes contact resistance between electrodes and the composite, which could be order of magnitude larger than the material resistance. For strain sensing, the specimen was subjected to increasing tensile strain until failure. In damage sensing, the specimens received different depth surface cuts across their width. During the tensile strain testing the specimens failed at a typical strain of about 4%. The corresponding change in resistance was in range of 2–3%. In damage sensing mode, changes of up to 40% in resistance were recorded for 75% thickness deep damage. For lower depth damages, the change in resistivity were about 4%–10%. The data obtained so far indicate that with proper technique, self-sensing of CNT-epoxy resin composites could be a viable method for monitoring applied strain and structural integrity.
Multiscale Simulation of Ballistic Composites for Blast Induced Traumatic Brain Injury Mitigation
Authors: Jenson Daniel , Unnikrishnan Vinu
Published: February 2016

The effectiveness of helmets in preventing internal damage due to blast waves requires understanding of not just the strength of the helmet material but also its energy absorption characteristics. To understand and develop ballistic helmets with improved protection, it is necessary to develop computational procedures that will enable the accurate modeling of traumatic head injuries as well as the precise measurement of the mechanical properties of composite materials used in helmets. In this study, a multiscale simulation strategy is used to estimate the mechanical characteristics of advanced composite structures with embedded nanostructures in a ballistic material. In most of the previous theoretical works, an analysis dedicated to improving the design of the helmet using composite nano-structures was not included due to a lack of understanding of the interactions of the nano-structures with the matrix materials. In this work, the role of the helmet on the over pressurization and impulse experienced by the head during blast wave is studied. The properties of the nano-composite materials are estimated using molecular dynamics (MD) simulations and the properties are scaled to the macroscopic level using continuum mechanics formulations. Finally, the analysis is also carried out on an unprotected head to compare the results to those obtained when protected by a helmet containing carbon nanotubes. The developed multiscale model can be used to improve the composition of helmets and the understanding of the traumatic effect of blast shock wave, thereby leading to the mitigation and prevention of traumatic head injuries.
Papers of note in
Science Translational Medicine
Authors: Gough Nancy R.
Published: February 2016

This week’s articles feature the use of nanoparticles containing a kinase inhibitor in cancer, causes of dermatitis, and a target for chronic pain.
Histone deacetylase fate switch
Authors: VanHook Annalisa M.
Published: February 2016

Histone deacetylase 3 promotes the expression of oligodendrocyte-specific genes and represses the expression of astrocyte-specific genes.
A role of the adaptive immune system in glucose homeostasis
Authors: Bronsart Laura L , Contag Christopher H
Published: February 2016

Objective

The immune system, including the adaptive immune response, has recently been recognized as having a significant role in diet-induced insulin resistance. In this study, we aimed to determine if the adaptive immune system also functions in maintaining physiological glucose homeostasis in the absence of diet-induced disease.

Research design and methods

SCID mice and immunocompetent control animals were phenotypically assessed for variations in metabolic parameters and cytokine profiles. Additionally, the glucose tolerance of SCID and immunocompetent control animals was assessed following introduction of a high-fat diet.

Results

SCID mice on a normal chow diet were significantly insulin resistant relative to control animals despite having less fat mass. This was associated with a significant increase in the innate immunity-stimulating cytokines granulocyte colony-stimulating factor, monocyte chemoattractant protein 1 (MCP1), and MCP3. Additionally, the SCID mouse phenotype was exacerbated in response to a high-fat diet as evidenced by the further significant progression of glucose intolerance.

Conclusions

These results support the notion that the adaptive immune system plays a fundamental biological role in glucose homeostasis, and that the absence of functional B and T cells results in disruption in the concentrations of various cytokines associated with macrophage proliferation and recruitment. Additionally, the absence of functional B and T cells is not protective against diet-induced pathology.
The China Patient-Centred Evaluative Assessment of Cardiac Events (China PEACE)-Prospective Study of 3-Vessel Disease: rationale and design
Authors: Rao Chenfei , Bongiovanni Tasce , Li Xi , Gao Huawei , Zhang Heng , Li Jing , Zhao Yan , Yuan Xin , Hua Kun , Hu Shengshou , Krumholz Harlan M , Jiang Lixin , Zheng Zhe
Published: February 2016

Introduction

Complex coronary artery disease (left main and three-vessel disease) carries high risks of adverse events and cost burden. However, in China, little is known about which patients are directed toward which treatment strategies and what outcomes are being achieved.

Methods and analysis

Using the China PEACE (Patient-centered Evaluative Assessment of Cardiac Events) research network, this prospective study of three-Vessel Disease, the China PEACE-3VD study, has a plan to consecutively register over 4000 patients with a diagnosis of 3VD and/or left-main disease by elective coronary angiography at 24 large cardiovascular centres in China. We centrally conducted medical record abstraction and SYNTAX Score calculation for all registered patients. The sites invited patients to the prospective cohort, and conducted 1-year follow-up on major events, including cardiac events, symptoms, secondary prevention and quality of life. The estimated entire sample size of eligible patients of 4000 was determined based on both feasibility and consideration of adequate statistical precision for describing the treatment decisions, guidelines adherence and appropriateness of treatment for patients with complex coronary artery diseases. The study is designed to investigate patient, clinician and hospital factors associated with each treatment strategy (percutaneous coronary intervention, coronary artery bypass grafting or medical therapy) as well as appropriateness of treatment choice, current guideline compliance and patient-reported outcomes for patients with complex coronary artery disease in large cardiovascular centres in China, as a foundation for enhanced knowledge in the field and to assist quality improvement initiatives.

Ethics and dissemination

The study protocol was approved by the ethics committee at the China National Center for Cardiovascular Diseases. Findings will be shared with participating hospitals, policymakers and the academic community, to promote quality monitoring, quality improvement and the efficient allocation, and use of coronary revascularisation procedures in China.

Trial registration number

NCT01625312; Pre-results
Decreased use of glucocorticoids in biological-experienced patients with rheumatoid arthritis who initiated intravenous abatacept: results from the 2-year ACTION study
Authors: Alten Rieke , Nüßlein Hubert , Galeazzi Mauro , Lorenz Hanns-Martin , Nurmohamed Michael T , Bensen William G , Burmester Gerd R , Peter Hans-Hartmut , Pavelka Karel , Chartier Mélanie , Poncet Coralie , Rauch Christiane , Elbez Yedid , Le Bars Manuela
Published: February 2016

Introduction

Prolonged glucocorticoid use may increase the risk of adverse safety outcomes, including cardiovascular events. The European League Against Rheumatism and the Canadian Rheumatology Association advise tapering glucocorticoid dose as rapidly as clinically feasible. There is a paucity of published data on RA that adequately describe concomitant treatment patterns.

Methods

ACTION (AbataCepT In rOutiNe clinical practice) is a non-interventional cohort study of patients from Europe and Canada that investigated the long-term retention of intravenous abatacept in clinical practice. We assessed concomitant glucocorticoids in patients with established RA who had participated in ACTION and received ≥1 biological agent prior to abatacept initiation.

Results

The analysis included 1009 patients. Glucocorticoids were prescribed at abatacept initiation in 734 (72.7%) patients at a median 7.5 mg/day dose (n=692). Of the patients who remained on abatacept at 24 months, 40.7% were able to decrease their dose of glucocorticoids, including 26.9% who decreased their dose from >5 mg/day to ≤5 mg/day.

Conclusion

Reduction and/or cessation of glucocorticoid therapy is possible with intravenous abatacept in clinical practice.
Fragment screening ofN-acetylmannosamine kinase reveals noncarbohydrate inhibitors
Authors: Aretz Jonas , Wratil Paul Robin , Wamhoff Eike-Christian , Nguyen Hoang Giang , Reutter Werner , Rademacher Christoph
Published: February 2016

Many biological processes from infection to tumor immune evasion are controlled by cell surface sialylation. To gather further insight into these processes, methods to alter cell surface sialylation are required. One way to achieve this is inhibiting the key enzyme of sialic acid de novo biosynthesis, the intracellular bifunctional UDP-N-acetylglucosamine epimerase/N-acetylmannosamine kinase (GNE/MNK). Here, we present low molecular weight inhibitors of MNK activity based on picolinic acid derivatives. They were identified in a fragment screening using19F NMR and validated in a biochemical inhibition assay followed by a structure–activity relationship analysis and docking. The optimized compound 6-carbamoylpicolinic acid inhibits MNK with a double-digit micromolar affinity. Its low molecular weight (166 Da) renders this picolinic acid derivative an exquisite starting point for the development of high-affinity MNK inhibitors, which may serve as molecular probes or lead candidates in future.
Microscopic models for the study of taxpayer audit effects
Authors: Bertotti Maria Letizia , Modanese Giovanni
Published: February 2016

A microscopic dynamic model is here constructed and analyzed, describing the evolution of the income distribution in the presence of taxation and redistribution in a society in which also tax evasion and auditing processes occur. The focus is on effects of enforcement regimes, characterized by different choices of the audited taxpayer fraction and of the penalties imposed to noncompliant individuals. A complex systems perspective is adopted: society is considered as a system composed by a large number of heterogeneous individuals. These are divided into income classes and may as well have different tax evasion behaviors. The variation in time of the number of individuals in each class is described by a system of nonlinear differential equations of the kinetic discretized Boltzmann type involving transition probabilities. A priori, one could think that audits and fines should have a positive effect on the reduction of economic inequality and correspondingly of the Gini index G. According to our model, however, such effect is rather small. In contrast, the effect on the increase of the tax revenue may be significant.
Direction of Arrival Estimation Under Near-Field Interference Using Matrix Filter
Authors: Liang Guolong , Zhao Wenbin , Fan Zhan
Published: February 2016

Direction of arrival (DOA) estimation is of great interest due to its wide applications in sonar, radar and many other areas. However, the near-field interference is always presented in the received data, which may result in degradation of DOA estimation. An approach which can suppress the near-field interference and preserve the far-field signal desired by using a spatial matrix filter is proposed in this paper and some typical DOA estimation algorithms are adjusted to match the filtered data. Simulation results show that the approach can improve capability of DOA estimation under near-field inference efficiently.
DEVELOPMENT OF LASER SURFACE TECHNOLOGIES FOR ANTI-CORROSION ON MAGNESIUM ALLOYS: A REVIEW
Authors: SUN RUJIAN , GUAN YINGCHUN , ZHU YING
Published: February 2016

Magnesium (Mg) alloys have been increasingly used in industries and biomaterial fields due to low density, high specific strength and biodegradability. However, poor surface-related properties are major factors that limit their practical applications. This paper mainly focuses on laser-based anti-corrosion technologies for Mg alloys, beginning with a brief review of conventional methods, and then demonstrates the feasibility of laser surface technologies including laser surface melting (LSM), laser surface alloying (LSA), laser surface cladding (LSC) and laser shock peening (LSP) in achieving enhancement of corrosion resistance. The mechanism and capability of each technique in corrosion resistance is carefully discussed. Finally, an outlook of the development of laser surface technology for Mg alloy is further concluded, aiming to serve as a guide for further research both in industry applications and biomedical devices.
EFFECTS OF BUFFER SALT CONCENTRATION ON THE DOMINATED DEPOSITION MECHANISM AND OPTICAL CHARACTERISTICS OF CHEMICALLY DEPOSITED CADMIUM SULFIDE THIN FILMS
Authors: KAKHAKI Z. MAKHDOUMI , YOUZBASHI A. , SANGPOUR P. , KAZEMZADEH A. , NADERI N. , BAZARGAN A. M.
Published: February 2016

Effects of buffer salt concentration on the rate of deposition, dominated deposition mechanism and subsequently the structural, morphological, and optical properties of cadmium sulfide (CdS) thin films deposited by chemical bath deposition (CBD) on glass substrate were investigated. The precursors were chosen to be cadmium chloride (CdCl2) as the cadmium source, thiourea (CS(NH[Formula: see text]) as the sulfur source, ammonium nitrate (NH4NO3) as the buffer salt and ammonia as the complexing agent and the pH controller. The influence of the NH4NO3 concentration on the structure, morphology, film uniformity, stoichiometry and optical properties of CdS thin films was also studied by X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX) spectroscope, uv–visible and photoluminescence (PL) spectroscopes. The XRD studies revealed that all the deposited films exhibited a (002)h/(111)c preferred orientation. The crystallite size was increased from 20[Formula: see text]nm to 30[Formula: see text]nm by the increase of concentration of NH4NO3 from 0.5[Formula: see text]M to 2.5[Formula: see text]M. The morphology of CdS thin films were agglomerated spherical particles consisted of smaller particles. The surface of thin films deposited at the NH4NO3 concentration of 0.5[Formula: see text]M was compact and smooth. The increase of the concentration of NH4NO3 decreased the packing density of the films. The optical band gap was in the range of 2.25–2.4[Formula: see text]eV, which was decreased by the decrement of packing density. The PL spectra showed two peaks centered at 400[Formula: see text]nm and 500[Formula: see text]nm which are attributed to violet and band-to-band emissions, respectively.
EFFECTS OF ELECTRODE RESISTANCE ON THE DIELECTRIC BEHAVIORS OF Au/BaxSr1−xTiO3/La1.1Sr0.9NiO4 CAPACITORS
Authors: QIU JIE , LIU GUOZHEN , WOLFMAN JÉRÔME
Published: February 2016

BaxSr[Formula: see text]TiO3 ([Formula: see text]) (BST) thin films were prepared on La[Formula: see text]Sr[Formula: see text]NiO4 (LSNO)/SrTiO3 (STO) structure by combinatorial pulsed laser deposition (comb-PLD). The capacitances of the Au/BST/LSNO capacitors exhibited strong frequency dependence especially when the applied frequency was higher than 10[Formula: see text]kHz. On the basis of an equivalent circuit model, we presented a theoretical simulation of the relationships between capacitance and frequency for the capacitors with different electrode serial resistances. Based on the fitting results, the observed strong frequency dependence of the measured capacitance at high frequency in our study could be ascribed to the large serial resistance of 750 [Formula: see text] for oxide electrode LSNO. Further simulation studies found that large serial resistance (1000 [Formula: see text]) could result in an apparent deviation from the intrinsic dielectric properties especially at high frequencies ([Formula: see text]100[Formula: see text]kHz) for capacitors with capacitances above 1[Formula: see text]nF. Our results provide useful information for the design of all-oxide electronic devices.
PREPARATION OF COMPOSITE COATING ON AZ91D MAGNESIUM ALLOY BY SILICA SOL-MICRO-ARC OXIDATION
Authors: SHAO ZHONGCAI , ZHANG FEIFEI , ZHAO RUIQIANG , SHEN XIAOYI
Published: February 2016

Composite coating was prepared on AZ91D magnesium alloy with a new method which combined silica sol with micro-arc oxidation (MAO). The MAO coating was prepared on the basis of MAO solution, and then coated by sol–gel process. The composite coating was obtained after second MAO treatment. Scanning electron microscopy coupled with X-ray diffraction (XRD), energy spectrum analysis and electrochemical testing was applied to characterize the properties of MAO coating and composite coating. The experimental test results indicated that the Si element derived from SiO2 gel particle embedded into the MAO coating by second MAO treatment. The surface of composite coating became dense and the holes were smaller with silica sol sealing process. The corrosion resistance of composite coating was improved than the MAO coating.
Partial regularity of suitable weak solutions to the multi-dimensional generalized magnetohydrodynamics equations
Authors: Ren Wei , Wang Yanqing , Wu Gang
Published: February 2016

In this paper, we are concerned with the partial regularity of the suitable weak solutions to the fractional MHD equations in [Formula: see text] for [Formula: see text]. In comparison with the work of the 3D fractional Navier–Stokes equations obtained by Tang and Yu in [Partial regularity of suitable weak solutions to the fractional Navier–Stokes equations, Comm. Math. Phys. 334 (2015) 1455–1482], our results include their endpoint case [Formula: see text] and the external force belongs to a more general parabolic Morrey space. Moreover, we prove some interior regularity criteria just via the scaled mixed norm of the velocity for the suitable weak solutions to the fractional MHD equations.
On conformally recurrent manifolds of dimension greater than 4
Authors: Mantica Carlo Alberto , Molinari Luca Guido
Published: February 2016

Conformally recurrent pseudo-Riemannian manifolds of dimension [Formula: see text] are investigated. The Weyl tensor is represented as a Kulkarni–Nomizu product. If the square of the Weyl tensor is non-zero, a covariantly constant symmetric tensor is constructed, that is quadratic in the Weyl tensor. Then, by Grycak’s theorem, the explicit expression of the traceless part of the Ricci tensor is obtained, up to a scalar function. The Ricci tensor has at most two distinct eigenvalues, and the recurrence vector is an eigenvector. Lorentzian conformally recurrent manifolds are then considered. If the square of the Weyl tensor is non-zero, the manifold is decomposable. A null recurrence vector makes the Weyl tensor of algebraic type IId or higher in the Bel–Debever–Ortaggio classification, while a time-like recurrence vector makes the Weyl tensor purely electric.
Facile Fabrication and Characterization of Ytterbium Oxide Hollow Spheres using Carbon Spheres as Template
Authors: Jiang Xueliang , Yu Lu , Yao Chu , You Feng , Zhang Jiao
Published: February 2016

Uniform rare-earth ytterbium oxide (Yb2O3) hollow microspheres have been successfully prepared via a urea-based homogenous precipitation method using carbon spheres as template, followed by a heat treatment. The main synthesis process was carried out in aqueous conditions without any organic solvents, surfactants or etching agents. X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area measurement were employed to characterize the samples. The results show that the final products can be indexed to cubic Yb2O3 phase with high purity. The as-obtained Yb2O3 microspheres with spherical shape and hollow structure are uniform in size and distribution of about 450[Formula: see text]nm and wall thickness of approximately 15[Formula: see text]nm.
Novel α-FeOOH Nanorods/Ag3PO4 Semiconductor Composites with Enhanced Photocatalytic Activity and Stability
Authors: Zhang Wei , Hu Chao , Tan Jie , Fan Zhujun , Chi Fangli , Sun Yaxin , Ran Songlin , Liu Xianguo , Lv Yaohui
Published: February 2016

The composite [Formula: see text]-FeOOH nanorods/Ag3PO4 photocatalyst has been successfully fabricated through a facile hydrothermal process combined with a successive in situ precipitation technique. The SEM and TEM images show that Ag3PO4 particles have been successfully loaded on the surface of FeOOH nanorods. The photocatalytic activities of the [Formula: see text]-FeOOH/Ag3PO4 composite were investigated for their efficiency on the degradation of Rhodamine B (RhB) under ultra-violet light and visible light irradiation, and the results showed that the [Formula: see text]-FeOOH/Ag3PO4 composite possessed remarkable photocatalytic activities. The enhanced photocatalytic activity can be attributed to the strong absorption in visible light and the effective separation of photogenerated hole–electron pairs between Ag3PO4 and [Formula: see text]-FeOOH.
Glucose detection in a highly scattering medium with diffuse photon-pair density wave
Authors: Yu Li-Ping , Wu Jheng-Syong , Chang Sheng-Yi , Chou Chien
Published: February 2016

We propose a novel optical method for glucose measurement based on diffuse photon-pair density wave (DPPDW) in a multiple scattering medium (MSM) where the light scattering of photon-pair is induced by refractive index mismatch between scatters and phantom solution. Experimentally, the DPPDW propagates in MSM via a two-frequency laser (TFL) beam wherein highly correlated pairs of linear polarized photons are generated. The reduced scattering coefficient [Formula: see text] and absorption coefficient [Formula: see text] of DPPDW are measured simultaneously in terms of the amplitude and phase measurements of the detected heterodyne signal under arrangement at different distances between the source and detection fibers in MSM. The results show that the sensitivity of glucose detection via glucose-induced change of reduced scattering coefficient ([Formula: see text]) is 0.049%[Formula: see text]mM[Formula: see text] in a 1% intralipid solution. In addition, the linear range of [Formula: see text] vs glucose concentration implies that this DPPDW method can be used to monitor glucose concentration continuously and noninvasively subcutaneously.
The high level language for system specification: A model-driven approach to systems engineering
Authors: Aliyu Hamzat Olanrewaju , Maïga Oumar , Traoré Mamadou Kaba
Published: February 2016

We present HiLLS (High Level Language for System Specification), a graphical formalism that allows to specify Discrete Event System (DES) models for analysis using methodologies like simulation, formal methods and enactment. HiLLS’ syntax is built from the integration of concepts from System Theory and Software Engineering aided by simple concrete notations to describe the structural and behavioral aspects of DESs. This paper provides the syntax of HiLLS and its simulation semantics which is based on the Discrete Event System Specification (DEVS) formalism. From DEVS-based Modeling and Simulation (M&S) perspective, HiLLS is a platform-independent visual language with generic expressions that can serve as a front-end for most existing DEVS-based simulation environments with the aid of Model-Driven Engineering (MDE) techniques. It also suggests ways to fill some gaps in existing DEVS-based visual formalisms that inhibit complete specification of the behavior of complex DESs. We provide a case study to illustrate the core features of the language.
Best analytical approximation of slow electrons and positrons elastic scattering cross-section: A comparative study
Authors: Bentabet A.
Published: February 2016

The purpose of this work is to determine the best analytical approximation of the differential cross-sections, used in Monte Carlo simulation, to study the electron and positron slowing down in solid targets in the energy range up to 10[Formula: see text]keV. For this, our comparative study has been carried out on the angular distribution of the scattering angle, the elastic total and the first transport cross-sections which are the essential quantities used generally in both the electron and the positron transport studies by using either stochastic or deterministic methods. Indeed, the obtained results using the relativistic partial wave expansion method and the backscattering coefficient (BSC) experimental data are used as criteria to evaluate the used model.
Distributed and Nonsteady-State Model of an Air Cooler Working with R22 and R410A
Authors: Nunes R. O. , Castro L. F. N. , Machado L. , Koury R. N. N.
Published: February 2016

The restrictions imposed by Montreal Protocol for use of CFCs fluids and Kyoto Protocol to HCFCs have motivated researchers and the industry to seek new alternatives. Within this context, R410A has emerged as one of the most likely replacement of R22. The purpose of this work is to develop a numerical model of an air cooler to simulate its behavior operating under dynamic conditions loaded with R22 or R410A refrigerant. The model divides the air cooler in volumes control in which mass, energy, and momentum balance equations are applied and solved. Theoretical data obtained by model simulations repeated tendencies observed in experimental data taken from literature. Model simulations have also shown that for a step change in the inlet refrigerant mass flow, the superheating response of air cooler is almost the same when it is working with R22 or R410A refrigerant.
Ultra-Wideband-Based Localization for Quadcopter Navigation
Authors: Guo Kexin , Qiu Zhirong , Miao Cunxiao , Zaini Abdul Hanif , Chen Chun-Lin , Meng Wei , Xie Lihua
Published: February 2016

Micro unmanned aerial vehicles (UAVs) are promising to play more and more important roles in both civilian and military activities. Currently, the navigation of UAVs is critically dependent on the localization service provided by the Global Positioning System (GPS), which suffers from the multipath effect and blockage of line-of-sight, and fails to work in an indoor, forest or urban environment. In this paper, we establish a localization system for quadcopters based on ultra-wideband (UWB) range measurements. To achieve the localization, a UWB module is installed on the quadcopter to actively send ranging requests to some fixed UWB modules at known positions (anchors). Once a distance is obtained, it is calibrated first and then goes through outlier detection before being fed to a localization algorithm. The localization algorithm is initialized by trilateration and sustained by the extended Kalman filter (EKF). The position and velocity estimates produced by the algorithm will be further fed to the control loop to aid the navigation of the quadcopter. Various flight tests in different environments have been conducted to validate the performance of UWB ranging and localization algorithm.
Relation of Lateral Antebrachial Cutaneous Nerve to the Volar Approach to Distal Radius
Authors: Tan Valerie H. , Tong Pei Yein , Liao Janice , Lee Han Jing , Foo Tun-Lin
Published: February 2016

Background: The anatomy of the lateral antebrachial cutaneous nerve (LABCN) in relation to volar approaches to the distal radius is not well visited. With the increasing popularity of distal radius fracture fixation with volar locking plates, it is prudent to study the innervation pattern of the LABCN to minimize the risk of nerve injury.

Methods: Ten cadaveric distal radial forearms were dissected to study the relationship between the LABCN, flexor carpi radialis (FCR), superficial branch of radial nerve (SBRN), and scaphoid tubercle (ST).

Results: The LABCN coursed closer to the FCR than the SBRN, with branches traversing the tendon in two specimens. The LABCN was also noted to be intimately related to the radial artery, with an average distance of the LABCN from the lateral border of FCR was 6.4mm distally and 9.6mm proximally.

Conclusions: There is a sparsely innervated corridor between the radial border of the FCR and terminal branches of the LABCN that provides safe access for volar approach to the distal radius.
Age-dependent differences in microglial responses to systemic inflammation are evident as early as middle age
Authors: Nikodemova Maria , Small Alissa L. , Kimyon Rebecca S. , Watters Jyoti J.
Published: February 2016

Whereas age increases microglial inflammatory activities and impairs their ability to effectively regulate their immune response, it is unclear at what age these exaggerated responses begin. We tested the hypotheses that augmented microglial responses to inflammatory challenge are present as early as middle age and that repeated stimulation of primed microglia in vivo would reveal microglial senescence. Microglial gene expression was investigated in a mouse model of repeated systemic inflammation induced by intraperitoneal injection of bacterial lipopolysaccharide (LPS). Following LPS, microglia from middle-aged mice (9–10 mo) displayed larger increases in Tnfα, Il-6, and Il-1β gene expression compared with young adults (2 mo). Similar results were observed in the spleens of middle-aged mice, indicating that exaggeration of both central and peripheral immune responses are already evident at early middle age. Interestingly, despite greater proinflammatory responses to the first LPS challenge in the aged mice, there were no age-dependent differences in either microglia or spleen following a subsequent LPS dose, suggesting that animals at this age retain the ability to effectively control their immune response following repeated challenge. The exacerbated microglial immune response to systemic inflammation at early middle age suggests that the CNS may be vulnerable to age-dependent alterations earlier than previously appreciated.
Hybrid Optimization Algorithm of Particle Swarm Optimization and Cuckoo Search for Preventive Maintenance Period Optimization
Authors: Guo Jianwen , Sun Zhenzhong , Tang Hong , Jia Xuejun , Wang Song , Yan Xiaohui , Ye Guoliang , Wu Guohong
Published: February 2016

All equipment must be maintained during its lifetime to ensure normal operation. Maintenance is one of the critical roles in the success of manufacturing enterprises. This paper proposed a preventive maintenance period optimization model (PMPOM) to find an optimal preventive maintenance period. By making use of the advantages of particle swarm optimization (PSO) and cuckoo search (CS) algorithm, a hybrid optimization algorithm of PSO and CS is proposed to solve the PMPOM problem. The test functions show that the proposed algorithm exhibits more outstanding performance than particle swarm optimization and cuckoo search. Experiment results show that the proposed algorithm has advantages of strong optimization ability and fast convergence speed to solve the PMPOM problem.
A Modified Fatigue Damage Model for High-Cycle Fatigue Life Prediction
Authors: Wang Meng , Fei Qingguo , Zhang Peiwei
Published: February 2016

Based on the assumption of quasibrittle failure under high-cycle fatigue for the metal material, the damage constitutive equation and the modified damage evolution equation are obtained with continuum damage mechanics. Then, finite element method (FEM) is used to describe the failure process of metal material. The increment of specimen’s life and damage state can be researched using damage mechanics-FEM. Finally, the lifetime of the specimen is got at the given stress level. The damage mechanics-FEM is inserted into ABAQUS with subroutine USDFLD and the Python language is used to simulate the fatigue process of titanium alloy specimens. The simulation results have a good agreement with the testing results under constant amplitude loading, which proves the accuracy of the method.
Unilateral Cervical Polyneuropathies following Concurrent Bortezomib, Cetuximab, and Radiotherapy for Head and Neck Cancer
Authors: Elghouche Alhasan , Shokri Tom , Qin Yewen , Wargo Susannah , Citrin Deborah , Van Waes Carter
Published: February 2016

We report a constellation of cervical polyneuropathies in a patient treated with concurrent bortezomib, cetuximab, and cisplatin alongside intensity modulated radiotherapy for carcinoma of the tonsil with neck metastasis. The described deficits include brachial plexopathy, cervical sensory neuropathy, and oculosympathetic, recurrent laryngeal, and phrenic nerve palsies within the ipsilateral radiation field. Radiation neuropathy involving the brachial plexus is typically associated with treatment of breast or lung cancer; however, increased awareness of this entity in the context of investigational agents with potential neuropathic effects in head and neck cancer has recently emerged. With this report, we highlight radiation neuropathy in the setting of investigational therapy for head and neck cancer, particularly since these sequelae may present years after therapy and entail significant and often irreversible morbidity.
Pharmacy Students’ Knowledge Assessment ofNaegleria fowleriInfection
Authors: Shakeel Sadia , Iffat Wajiha , Khan Madeeha
Published: February 2016

A cross-sectional study was conducted from April to August 2015 to assess the knowledge of pharmacy students towardsNaegleria fowleriinfection. A questionnaire was distributed to senior pharmacy students in different private and public sector universities of Karachi. Descriptive statistics were used to demonstrate students’ demographic information and their responses to the questionnaire. Pearson chi-square test was adopted to assess the relationship between independent variables and responses of students. The study revealed that pharmacy students were having adequate awareness ofNaegleria fowleriinfection and considered it as a serious health issue that necessitates instantaneous steps by the government to prevent the general public from the fatal neurological infection. The students recommended that appropriate methods should be projected in the community from time to time that increases public awareness about the associated risk factors.
X-Ray Scatter Correction on Soft Tissue Images for Portable Cone Beam CT
Authors: Aootaphao Sorapong , Thongvigitmanee Saowapak S. , Rajruangrabin Jartuwat , Thanasupsombat Chalinee , Srivongsa Tanapon , Thajchayapong Pairash
Published: February 2016

Soft tissue images from portable cone beam computed tomography (CBCT) scanners can be used for diagnosis and detection of tumor, cancer, intracerebral hemorrhage, and so forth. Due to large field of view, X-ray scattering which is the main cause of artifacts degrades image quality, such as cupping artifacts, CT number inaccuracy, and low contrast, especially on soft tissue images. In this work, we propose the X-ray scatter correction method for improving soft tissue images. The X-ray scatter correction scheme to estimate X-ray scatter signals is based on the deconvolution technique using the maximum likelihood estimation maximization (MLEM) method. The scatter kernels are obtained by simulating the PMMA sheet on the Monte Carlo simulation (MCS) software. In the experiment, we used the QRM phantom to quantitatively compare with fan-beam CT (FBCT) data in terms of CT number values, contrast to noise ratio, cupping artifacts, and low contrast detectability. Moreover, the PH3 angiography phantom was also used to mimic human soft tissues in the brain. The reconstructed images with our proposed scatter correction show significant improvement on image quality. Thus the proposed scatter correction technique has high potential to detect soft tissues in the brain.
Curcumin Protects Neonatal Rat Cardiomyocytes against High Glucose-Induced Apoptosis via PI3K/Akt Signalling Pathway
Authors: Yu Wei , Zha Wenliang , Ke Zhiqiang , Min Qing , Li Cairong , Sun Huirong , Liu Chao
Published: February 2016

The function of curcumin on NADPH oxidase-related ROS production and cardiac apoptosis, together with the modulation of protein signalling pathways, was investigated in cardiomyocytes. Primary cultures of neonatal rat cardiomyocytes were exposed to 30 mmol/L high glucose with or without curcumin. Cell viability, apoptosis, superoxide formation, the expression of NADPH oxidase subunits, and potential regulatory molecules, Akt and GSK-3β, were assessed in cardiomyocytes. Cardiomyocytes exposure to high glucose led to an increase in both cell apoptosis and intracellular ROS levels, which were strongly prevented by curcumin treatment (10 μM). In addition, treatment with curcumin remarkably suppressed the increased activity of Rac1, as well as the enhanced expression ofgp91phoxandp47phoxinduced by high glucose. Lipid peroxidation and SOD were reversed in the presence of curcumin. Furthermore, curcumin treatment markedly inhibited the reduced Bcl-2/Bax ratio elicited by high glucose exposure. Moreover, curcumin significantly increased Akt and GSK-3βphosphorylation in cardiomyocytes treated with high glucose. In addition, LY294002 blocked the effects of curcumin on cardiomyocytes exposure to high glucose. In conclusion, these results demonstrated that curcumin attenuated high glucose-induced cardiomyocyte apoptosis by inhibiting NADPH-mediated oxidative stress and this protective effect is most likely mediated by PI3K/Akt-related signalling pathway.
An Elliptic Curve Based Schnorr Cloud Security Model in Distributed Environment
Authors: Muthurajan Vinothkumar , Narayanasamy Balaji
Published: February 2016

Cloud computing requires the security upgrade in data transmission approaches. In general, key-based encryption/decryption (symmetric and asymmetric) mechanisms ensure the secure data transfer between the devices. The symmetric key mechanisms (pseudorandom function) provide minimum protection level compared to asymmetric key (RSA, AES, and ECC) schemes. The presence of expired content and the irrelevant resources cause unauthorized data access adversely. This paper investigates how the integrity and secure data transfer are improved based on the Elliptic Curve based Schnorr scheme. This paper proposes a virtual machine based cloud model with Hybrid Cloud Security Algorithm (HCSA) to remove the expired content. The HCSA-based auditing improves the malicious activity prediction during the data transfer. The duplication in the cloud server degrades the performance of EC-Schnorr based encryption schemes. This paper utilizes the blooming filter concept to avoid the cloud server duplication. The combination of EC-Schnorr and blooming filter efficiently improves the security performance. The comparative analysis between proposed HCSA and the existing Distributed Hash Table (DHT) regarding execution time, computational overhead, and auditing time with auditing requests and servers confirms the effectiveness of HCSA in the cloud security model creation.
Small Intestinal and Mesenteric Multiple Gastrointestinal Stromal Tumors Causing Occult Bleeding
Authors: Dinc Tolga , Kayilioglu Selami Ilgaz , Erdogan Ahmet , Cetinkaya Erdinc , Akgul Ozgur , Coskun Faruk
Published: February 2016

Gastrointestinal stromal tumors are the meseancymal neoplasms which may involve any part of gastrointestinal tract. C-Kit and platelet derived factor receptor alpha polypeptide are believed to be responsible for the genetic basis. This case presentation aimed to discuss the diagnostic and therapeutic modality of multiple small intestinal, omental, and mesenteric GISTs with different sizes which caused occult bleeding in a 43-year-old male patient.
IgA Nephropathy in a Patient Presenting with Pseudotumor Cerebri
Authors: Ahmed Umair Syed , Bacaj Patrick , Iqbal Hafiz Imran , Onder Songul
Published: February 2016

IgA nephropathy is the most common glomerulonephritis worldwide and typically has minimal signs for chronicity in histopathology at the time of initial presentation. Pseudotumor cerebri (PTC) is characterized by increased intracranial pressure in the absence of any intracranial lesions, inflammation, or obstruction. PTC has been reported in renal transplant and dialysis patients, but we are unaware of any reports of pseudotumor cerebri in patients with IgA nephropathy. We report a case of a young female who presented with signs and symptoms of pseudotumor cerebri and was subsequently diagnosed with IgA nephropathy and end-stage renal disease. To our knowledge this is the first report of IgA nephropathy presenting as end-stage renal disease in a patient who presented with pseudotumor cerebri.
The Difference of Structural State and Deformation Behavior between Teenage and Mature Human Dentin
Authors: Panfilov Peter , Zaytsev Dmitry , Antonova Olga V. , Alpatova Victoria , Kiselnikova Larissa P.
Published: February 2016

Objective. The cause of considerable elasticity and plasticity of human dentin is discussed in the relationship with its microstructure.Methods. Structural state of teenage and mature human dentin is examined by using XRD and TEM techniques, and their deformation behavior under compression is studied as well.Result. XRD study has shown that crystallographic type of calcium hydroxyapatite in human dentin (calcium hydrogen phosphate hydroxide Ca9HPO4(PO4)5OH; Space Group P63/m (176);a= 9,441 A;c= 6,881 A;c/a= 0,729; Crystallite (Scherrer) 200 A) is the same for these age groups. In both cases, dentin matrix is X-ray amorphous. According to TEM examination, there are amorphous and ultrafine grain phases in teenage and mature dentin. Mature dentin is stronger on about 20% than teenage dentin, while teenage dentin is more elastic on about 20% but is less plastic on about 15% than mature dentin.Conclusion. The amorphous phase is dominant in teenage dentin, whereas the ultrafine grain phase becomes dominant in mature dentin. Mechanical properties of human dentin under compression depend on its structural state, too.
Risk of Adverse Infant Outcomes Associated with Maternal Tuberculosis in a Low Burden Setting: A Population-Based Retrospective Cohort Study
Authors: LaCourse Sylvia M. , Greene Sharon A. , Dawson-Hahn Elizabeth E. , Hawes Stephen E.
Published: February 2016

Background. Maternal tuberculosis (TB) may be associated with increased risk of adverse infant outcomes.Study Design. We examined the risk of low birth weight (LBW), small for gestational age (SGA), and preterm birth (<37 weeks) associated with maternal TB in a retrospective population-based Washington State cohort using linked infant birth certificate and maternal delivery hospitalization discharge records. We identified 134 women with births between 1987 and 2012 with TB-associated ICD-9 diagnosis codes at hospital delivery discharge and 536 randomly selected women without TB, frequency matched 4 : 1 on delivery year. Multinomial logistic regression analyses were performed to compare the risk of LBW, SGA, and preterm birth between infants born to mothers with and without TB.Results. Infants born to women with TB were 3.74 (aRR 95% CI 1.40–10.00) times as likely to be LBW and 1.96 (aRR 95% CI 0.91–4.22) as likely to be SGA compared to infants born to mothers without TB. Risk of prematurity was similar (aRR 1.01 95% CI 0.39–2.58).Conclusion. Maternal TB is associated with poor infant outcomes even in a low burden setting. A better understanding of the adverse infant outcomes associated with maternal TB, reflecting recent trends in US TB epidemiology, may inform potential targeted interventions in other low prevalence settings.
HPTLC Fingerprint Profile (Phenolics) of Selected Cyathea Species from Western Ghats, South India
Authors: Narayanan Janakiraman , Marimuthu alias Antonysamy Johnson
Published: February 2016

HPTLC analysis was performed to study the phenolics, flavonoids, and tannins profile of Cyathea nilgirensis Holttum, Cyathea gigantea (Wall. ex. Hook.) Holttum, and Cyathea crinita (Hook.) Copel. The maximum number of bands was observed in the ethanolic extracts of C. crinita. The phenolic bands with Rf values 0.05, 0.32, 0.43, 0.75 (quercetin), and 0.83 demonstrated their occurrence in all the three studied species of Cyathea. Flavonoids with Rf values 0.05, 0.23, 0.30, 0.43, and 0.73 showed their presence in the three studied species of Cyathea. Tannins with the Rf values 0.05, 0.09, and 0.82 determined their existence in all the three studied Cyathea species. Gallic acid was present only in C. crinita with the Rf value 0.49. The developed HPTLC profiles can be used for identification and quantitative determination of phenolics, flavonoids, and tannins. This method is also suitable for rapid screening of Cyathea species for chemotypic assessment and also for quality control purposes.
On the Electronic Effect of V, Fe, and Ni on MgO(100) and BaO(100) Surface: An Explanation from a Periodic Density Functional
Authors: Añez Rafael , Sierraalta Aníbal
Published: February 2016

A periodic density functional study of the V, Fe, and Ni sublayer doped MgO(100) and BaO(100) surfaces was carried out using a periodic approach in the context of the GGA approximation. Results suggest that doping atoms accommodate better in the MgO than in BaO because covalent radii of the doping atoms are closer to that of the Mg atom. Sizes of the doping atom, bulk forces, and electronic effects play an important role in the structural changes observed in doped surfaces studied herein. From all the doped studies, Ni doped Ba(100) surface is shown to be a promising material for trapping molecules with partially occupied states.