bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation of the growth process of icy materials in interparticle spaces: phase-contrast X-ray imaging of clathrate hydrate
Authors: Takeya Satoshi , Gotoh Yoshito , Yoneyama Akio , Hyodo Kazuyuki , Takeda Tohoru
Published: May 2015

The visualization of temperature-controlled crystal growth and dissociation of tetrahydrofuran clathrate hydrates and ice in the interparticle spaces between beads is presented. Phase-contrast X-ray imaging using synchrotron X-ray radiation is a unique technique to study clathrate hydrates coexisting with both ice and liquid water and is used here to observe tetrahydrofuran hydrate and ice formation in situ. The nondestructive images obtained reveal a morphology change of tetrahydrofuran clathrate hydrate grown under isothermal temperature conditions at 253 K, which may be caused by the thermal history of crystallization of the clathrate hydrate. In addition, the water freezing process in the interparticle spaces between is observed using phase-contrast X-ray imaging. This method is useful for understanding the kinetics of clathrate hydrates in interparticle spaces.
Energy allocation strategies of young temperate fish: an eco-genetic modeling approach
Authors: Ivan Lori N. , Höök Tomas O.
Published: May 2015

We use an individual-based eco-genetic model to explore the relative selective pressures of size-dependent predation, overwinter mortality, and density-dependent energy acquisition in structuring plastic and adaptive energy allocation during the first year of life of a temperate fish population. While several patterns emerging from a suite of eco-genetic model simulations were consistent with past theoretical models and empirical evaluations of energy allocation by young fishes, results also highlight the utility of eco-genetic models for simultaneous consideration of plastic and adaptive processes. Across simulations, variation in genetic control of energy allocation was limited during very early ontogeny when size-dependent predation pressure was particularly high. While this stabilizing selection on energy allocation diminished later in the growing season, predation, overwinter mortality, and density-dependent processes simultaneously structured energy partitioning later in ontogeny through the interactive influence of plastic and adaptive processes. Specifically, high risk of overwinter mortality and low predation selected for high prioritization of energy storage. We suggest that simulations demonstrate the utility of eco-genetic models for generating null predictions of how selective pressures may structure expression of life history traits, such as early life energy allocation.
Proton computed tomography
Authors: Bucciantonio Martina , Sauli Fabio
Published: May 2015

Proton computed tomography (pCT) is a diagnostic method capable of in situ imaging the three-dimensional density distribution in a patient before irradiation with charged particle beams. Proposed long time ago, this technology has been developed by several groups, and may become an essential tool for advanced quality assessment in hadrontherapy. We describe the basic principles of the method, its performance and limitations as well as provide a summary of experimental systems and of results achieved.
Influence of quantized massive matter fields on the Casimir effect
Authors: Sitenko Yu. A.
Published: May 2015

Charged massive matter fields of spin-0 and spin-[Formula: see text] are quantized in the presence of an external uniform magnetic field in a spatial region bounded by two parallel plates. The most general set of boundary conditions at the plates, that is required by mathematical consistency and the self-adjointness of the Hamiltonian operator, is employed. The vacuum fluctuations of the matter field in the case of the magnetic field orthogonal to the plates are analyzed, and it is shown that the pressure from the vacuum onto the plates is positive and independent of the boundary condition, as well as of the distance between the plates. Possibilities of the detection of this new-type Casimir effect are discussed.
Enhanced Usage of Keys Obtained by Physical, Unconditionally Secure Distributions
Authors: Kish Laszlo B. , Granqvist Claes-Göran
Published: May 2015

Unconditionally secure physical key distribution schemes are very slow, and it is practically impossible to use a one-time-pad based cipher to guarantee unconditional security for the encryption of data because using the key bits more than once gives out statistical information, for example via the known-plain-text-attack or by utilizing known components of the protocol and language statistics. Here, we outline a protocol that reduces this speed problem and allows almost-one-time-pad based communication with an unconditionally secure physical key of finite length. The physical, unconditionally secure key is not used for data encryption but is employed in order to generate and share a new software-based key without any known-plain-text component. The software-only-based key distribution is then changed from computationally secure to unconditionally secure, because the communicated key-exchange data (algorithm parameters, one-way functions of random numbers, etc.) are encrypted in an unconditionally secure way with a one-time-pad. For practical applications, this combined physical/software key distribution based communication looks favorable compared to the software-only and physical-only key distribution based communication whenever the speed of the physical key distribution is much lower than that of the software-based key distribution. A mathematical security proof of this new scheme remains an open problem.
ESTIMATION OF THE WITHDRAWAL PERIOD FOR AMOXICILLIN IN POMPANO (TRACHINOTUS BLOCHII) SERUM AND MUSCLE
Authors: Wang Chia-Yih , Sheu Shi-Yuan , Wang Jiann-Hsiung , Chang Ming-Huang , Chen Pay-Heng , Chang Tong-Hsuan , Kuo Tzong-Fu
Published: May 2015

Amoxicillin is one of the most popular antibiotics used in aquaculture. To ensure the residue of amoxicillin in the serum and the muscle of pompano (Trachinotus blochii) is below the established tolerance levels; we used reversed phase high-performance liquid chromatography (HPLC) to measure the amoxicillin in pompano after oral administration. The pharmacokinetics of amoxicillin in the serum and the muscle of pompano were established by single oral administration or administrations for five consecutive days at the dose of 40 mg/kg. After different depletion periods, amoxicillin residue was analyzed in both the serum and the muscle fillets by HPLC. The verified concentrations of this method were 0.01 to 10 μg/mL; the limit of detection (LOD) and the limit of quantitation (LOQ) were 0.04 and 0.1 μg/g. The concentration of amoxicillin in the serum of pompano reached the maximum threshold of 7.36 μg/g after 0.5 h depletion in the experiment with a single dose of amoxicillin (40 mg/kg of body weight). In addition, the maximal concentration (1.96 μg/g) of amoxicillin was detected in the muscle 2 h after depletion. Furthermore, the residue levels had decreased below the limit of detection after 48 h and 72 h in the serum and the muscle. Here we also suggested that 5 days of withdrawal were required after the multiple dosing of amoxicillin.
Effective Downsizing of a Large Oesophageal Gastrointestinal Stromal Tumour with Neoadjuvant Imatinib Enabling an Uncomplicated and without Tumour Rupture Laparoscopic-Assisted Ivor-Lewis Oesophagectomy
Authors: Neofytou Kyriakos , Costa Neves Mafalda , Giakoustidis Alexandros , Benson Charlotte , Mudan Satvinder
Published: May 2015

Neoadjuvant imatinib for gastrointestinal stromal tumours (GISTs) is increasingly used nowadays. As oesophagectomy is associated with high morbidity and mortality, a preoperative downsizing of an oesophageal GIST to limit the extent of resection would be ideal. Because these tumours are rare and neoadjuvant treatment with imatinib is recent, there is limited literature available regarding neoadjuvant administration of imatinib in patients with oesophageal GISTs. A 50-year-old woman presented with total dysphagia. An upper endoscopy and biopsy revealed a large submucosal KIT-positive GIST obstructing the mid oesophagus. CT confirmed a lesion measuring 99 mm × 50 mm × 104 mm. Because the size and location of the tumour increased the risk of intraoperative rupture, it was decided to administer preoperative imatinib. The patient had an excellent clinical and radiological response. Her dysphagia gradually resolved and the follow-up CT scans of the first 10 months showed a gradually reducing tumour size to 54 mm × 33 mm × 42 mm. The patient underwent an uneventful laparoscopic-assisted Ivor-Lewis oesophagectomy. Postoperatively, the patient continued with adjuvant imatinib. At the last follow-up, 1 year from operation and 38 months from the diagnosis, the patient is disease free.
Bcl-xL Genetic Modification Enhanced the Therapeutic Efficacy of Mesenchymal Stem Cell Transplantation in the Treatment of Heart Infarction
Authors: Xue Xiaodong , Liu Yu , Zhang Jian , Liu Tao , Yang Zhonglu , Wang Huishan
Published: May 2015

Objectives.Low survival rate of mesenchymal stem cells (MSCs) severely limited the therapeutic efficacy of cell therapy in the treatment of myocardial infarction (MI). Bcl-xL genetic modification might enhance MSC survival after transplantation.Methods.Adult rat bone marrow MSCs were modified with human Bcl-xL gene (hBcl-xL-MSCs) or empty vector (vector-MSCs). MSC apoptosis and paracrine secretions were characterized using flow cytometry, TUNEL, and ELISAin vitro.In vivo, randomized adult rats with MI received myocardial injections of one of the three reagents: hBcl-xL-MSCs, vector-MSCs, or culture medium. Histochemistry, TUNEL, and echocardiography were carried out to evaluate cell engraftment, apoptosis, angiogenesis, scar formation, and cardiac functional recovery.Results.In vitro, cell apoptosis decreased 43%, and vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and plate-derived growth factor (PDGF) increased 1.5-, 0.7-, and 1.2-fold, respectively, in hBcl-xL-MSCs versus wild type and vector-MSCs.In vivo, cell apoptosis decreased 40% and 26% in hBcl-xL-MSC group versus medium and vector-MSC group, respectively. Similar results were observed in cell engraftment, angiogenesis, scar formation, and cardiac functional recovery.Conclusions.Genetic modification of MSCs with hBcl-xL gene could be an intriguing strategy to improve the therapeutic efficacy of cell therapy in the treatment of heart infarction.
Feasibility Verification of Mountable PZT-Interface for Impedance Monitoring in Tendon-Anchorage
Authors: Huynh Thanh-Canh , Park Young-Hwan , Park Jae-Hyung , Kim Jeong-Tae
Published: May 2015

This study has been motivated to numerically evaluate the performance of the mountable PZT-interface for impedance monitoring in tendon-anchorage. Firstly, electromechanical impedance monitoring and feature classification methods are outlined. Secondly, a structural model of tendon-anchorage subsystem with mountable PZT-interface is designed for impedance monitoring. Finally, the feasibility of the mountable PZT-interface is numerically examined. A finite element (FE) model is designed for the lab-scaled tendon-anchorage. The FE model of the PZT-interface is tuned as its impedance signatures meet the experimental test results at the same frequency ranges and also with identical patterns. Equivalent model properties of the FE model corresponding to prestress forces inflicted on the lab-tested structure are identified from the fine-tuning practice.
Effect of Dilution on Microstructure and Wear Resistance of a Fe-Based Hardfacing Alloy with a High Amount of Carbide-Forming Elements
Authors: Rovatti L. , Lemke J. N. , Lecis N. , Stejskal O. , Vedani M.
Published: May 2015

Hardfacing is a widely diffused technique adopted to increase service life of parts for heavy-duty applications. Even though hardfacing alloys feature optimized chemistry and microstructure for specific service conditions, dilution with substrate modifies the resulting properties along a significant fraction of the deposit thickness. In particular, C and B diffusion to the substrate alters hypereutectic alloys reducing the carbide-forming ability and modifying the solidification sequence. In the present paper, the effect of dilution on a hypereutectic Fe-C-B based alloy containing Cr and Mo was investigated. The effect of dilution on the reference alloy was studied by producing laboratory castings with an increased amount of Fe, up to 50 mass %. The obtained results were compared with the dilution of the hardfacing alloy cast on steel substrates. The microstructural evolution was analyzed by XRD (X-ray diffraction), differential scanning calorimetry (DSC), optical microscopy (OM), and scanning electron microscopy (SEM), whereas mechanical behaviour was evaluated by hardness measurements and wear resistance by pin-on-disc tests.
Effects of Erroneous CSI on the Performance of Multiple-Transmit Antenna Selection
Authors: Zhuang Mingjie
Published: May 2015

The paper assumes that the channel state information (CSI) is available at the receiver and is known partially at the transmitter through a feedback channel. The bit error rate (BER) performance of multiple transmit antenna selection (MTAS) for the multiple-input and single-output (MISO) system with STBC (MTAS/MISO-STBC) will be investigated in detail. Meanwhile, the selection criterion that maximizes the channel Frobenius norm or minimizes the error probability of MTAS/MISO-STBC system is employed. In two cases of erroneous CSI (ECSI) and inerrable CSI (ICSI), wireless channels of the MTAS systems are modeled and their analytical expressions are derived. For the case of ICSI, the exact BER expressions of the Chernoff upper bound (CUB) for both the MISO-STBC system of full complexity and MTAS system are evaluated, respectively. Next, for the ECSI case, a comprehensive analytical expression of BER CUB for the same system is derived in detail. Finally, extensive Monte-Carlo simulations are presented to support and validate our numerical analysis proposed in this paper. Both the simulating results and the numerical results show that MTAS can reduce effectively the effect of the erroneous CSI.
Facile Synthesis of N‐Doped BiOCl Photocatalyst by an Ethylenediamine‐Assisted Hydrothermal Method
Authors: Chen Guihua , Chen Gangling , Wang Yong , Wang Qingfeng , Zhang Zhen
Published: May 2015

A nitrogen doped BiOCl (N‐BiOCl) photocatalyst was synthesized and characterized using an ethylenediamine‐assisted hydrothermal method. The N‐BiOCl sample demonstrated the same tetragonal crystal structure as the as‐prepared pure BiOCl sample. SEM results indicated that N‐BiOCl sample was self‐assembled by nanoplates to provide an aggregated flower‐like microstructure. Doped nitrogen was substituted for oxygen in the crystal lattice of BiOCl, causing a red shift for N‐BiOCl sample compared to BiOCl sample. The N‐BiOCl sample exhibited higher photocatalytic activity in the degradation of Rhodamine B under visible light than observed in BiOCl sample, and the stability of the sample was verified. Meanwhile, speculative causes for the enhancement in the photocatalytic activity of N‐BiOCl sample were also proposed.
Codimension-Two Grazing Bifurcations in Three-Degree-of-Freedom Impact Oscillator with Symmetrical Constraints
Authors: Li Qunhong , Chen Pu , Xu Jieqiong
Published: May 2015

This paper investigates the codimension-two grazing bifurcations of a three-degree-of-freedom vibroimpact system with symmetrical rigid stops since little research can be found on this important issue. The criterion for existence of double grazing periodic motion is presented. Using the classical discontinuity mapping method, the Poincaré mapping of double grazing periodic motion is obtained. Based on it, the sufficient condition of codimension-two bifurcation of double grazing periodic motion is formulated, which is simplified further using the Jacobian matrix of smooth Poincaré mapping. At the end, the existence regions of different types of periodic-impact motions in the vicinity of the codimension-two grazing bifurcation point are displayed numerically by unfolding diagram and phase diagrams.
Irisin and Myonectin Regulation in the Insulin Resistant Muscle: Implications to Adipose Tissue: Muscle Crosstalk
Authors: Gamas Luis , Matafome Paulo , Seiça Raquel
Published: May 2015

Myokines are peptides produced and secreted by the skeletal muscle, with autocrine, paracrine, and endocrine actions. Many of them are overexpressed during physical exercise and appear to contribute to the benefits of exercise to metabolic homeostasis. Irisin, resulting from the cleavage of the membrane protein FNDC5, was shown to induce adipocyte browning, with increased lipid oxidation and thermogenesis. Myonectin was only recently discovered and initial studies revealed a role in fatty acid uptake and oxidation in adipose tissue and liver. However, the mechanisms of their regulation by exercise are not entirely established. Impaired secretion and action of myokines, such as irisin and myonectin, may have a role in the establishment of insulin resistance. On the other hand, several studies have shown that insulin resistance in the skeletal muscle may change myokines expression and secretion. This may have consequences on lipid and glucose metabolism in adipose tissue and lead to a vicious cycle between impaired myokines production and insulin resistance. This review summarizes the current knowledge about the influence of skeletal muscle insulin resistance on the secretion of irisin and myonectin, as well as its impact on adipose tissue metabolism.
PRP Augmentation for ACL Reconstruction
Authors: Andriolo Luca , Di Matteo Berardo , Kon Elizaveta , Filardo Giuseppe , Venieri Giulia , Marcacci Maurilio
Published: May 2015

Current research is investigating new methods to enhance tissue healing to speed up recovery time and decrease the risk of failure in Anterior Cruciate Ligament (ACL) reconstructive surgery. Biological augmentation is one of the most exploited strategies, in particular the application of Platelet Rich Plasma (PRP). Aim of the present paper is to systematically review all the preclinical and clinical papers dealing with the application of PRP as a biological enhancer during ACL reconstructive surgery. Thirty-two studies were included in the present review. The analysis of the preclinical evidence revealed that PRP was able to improve the healing potential of the tendinous graft both in terms of histological and biomechanical performance. Looking at the available clinical evidence, results were not univocal. PRP administration proved to be a safe procedure and there were some evidences that it could favor the donor site healing in case of ACL reconstruction with patellar tendon graft and positively contribute to graft maturation over time, whereas the majority of the papers did not show beneficial effects in terms of bony tunnels/graft area integration. Furthermore, PRP augmentation did not provide superior functional results at short term evaluation.
Seismic Fortification Analysis of the Guoduo Gravity Dam in Tibet, China
Authors: Lin Peng , Zheng Wenwei , Huang Bo , Zhang Haichao
Published: May 2015

The primary aim of this research was to analyze the seismic performance of the Guoduo gravity dam. A nonlinear FEM method was implemented to study the deformation, stress, and overall stability of dam under both static and dynamic loading conditions, including both normal and overloading conditions. A dam seismic failure risk control method is proposed based on the cracking mechanism induced by the dynamic load to ensure dam safety and stability. Numerical simulation revealed that (1) under normal static and dynamic loading the symmetry of the displacement distributions is good, showing that the dam abutments and riverbed foundation have good overall stiffness. The stress distribution is a safe one for operation under both normal water loading and seismic loading. (2) Attention should be paid to the reinforcement design of outlets of the diversion dam monoliths, and enhance the capability of sustaining that tensile stress of dam monoliths. (3) The shape of the dam profile has a significant effect on the dynamic response of the dam. (4) By employing the “overload safety factor method,” the overall seismic fortification is as follows:K1=1.5,K2=2~3, andK3=3~4.
Residual Effects of Lime- and Clay-Amended Biosolids Applied to Coarse-Textured Pasture Soil
Authors: Shanmugam Sanjutha , Abbott Lynette K.
Published: May 2015

This study investigated whether there was residual effect of application of lime- and clay-amended biosolids (LaBC®) on ryegrass growth and soil microbial biomass in a coarse-textured, acid pasture soil. Reapplied LaBC®increased fertiliser-use efficiency and plant growth in this glasshouse experiment. Soil management history was established with a single application of LaBC®(50 t ha−1wet weight equivalent) with or without inorganic fertiliser (NPK) prior to growing annual ryegrass for 5 cycles. In cycle 6 there was no residual nutrient effect of the original application of LaBC®but there was a residual liming effect of the previously applied LaBC®. A nutrient effect of reapplied LaBC®in plant growth cycle 6, had little residual benefit in cycle 7. The residual concentration of inorganic N remaining in this coarse-textured acid soil after a single application of LaBC®was negligible and did not appear to be a risk to the environment when applied at 50 t ha−1wet weight equivalent.
A New Compression-Torsion-Tribometer with Scalable Contact Pressure for Characterization of Tool Wear during Plastic Deformation
Authors: Teller Marco , Seuren Simon , Bambach Markus , Hirt Gerhard
Published: May 2015

A contact pressure which reaches up to ten times the yield stress of the workpiece material is characteristic for cold extrusion processes. Common tests for friction and wear are limited to rather low contact pressures. Thus, the aim of this paper is to present a new compression-torsion-tribometer which is able to scale the contact pressure to a multiple of the yield stress of the workpiece. In order to enable a contact pressure that greatly exceeds the yield stress of the workpiece material, the workpiece specimen is encapsulated laterally. As main parameters, contact pressure, glide length, and relative velocity can be adjusted independently, thus allowing for multiple load cycles. The resulting torque is measured continuously as an indicator for wear. Afterwards wear can be also quantified by examination of surfaces. Hence, the developed setup enables a comparison of tool surfaces and coatings and a characterization of wear behaviour under high contact pressure.
On the Role of Oxidation in Tribological Contacts under Environmental Conditions
Authors: Merz Rolf , Brodyanski Alexander , Kopnarski Michael
Published: May 2015

Oxidation processes in tribological steel contacts are investigated, which are treated in a dry sliding, linear reciprocating model tribometer, by EDX (energy dispersive X-ray spectroscopy), AES (Auger electron spectroscopy), and HREFTEM (high resolution energy filtered transmission electron microscopy). Typical for steel contacts under environmental conditions is the feature that the counterparts are separated by oxide layers, which influence the tribological properties. And vice versa the tribological load will influence and change the oxide layers. The interaction of this dynamically coupled system was resolved by focussing the postexperimental surface analysis to long time stable balance states. As special challenge for the analyst of the tribological experiment under environmental conditions a postexperimental grown oxide layer covers the tribological induced changes and has to be distinguished from the tribological induced changes. Thick oxide layers, formed during the tribological load, were observed, which start to grow in form of islands and at the end separate the metallic bulk materials of the counterparts completely and avoid direct metal-metal contact. Thicknesses up to some microns strength, exceeding native oxide layers by magnitudes, were reached. Ploughing under fresh surface oxide and compacting and embedding of fresh oxidized debris particles were identified as main mechanisms responsible for the growing of these thick oxide layers.
Total and High Molecular Weight Adiponectin Levels and Prediction of Cardiovascular Risk in Diabetic Patients
Authors: Horáková Dagmar , Azeem Kateřina , Benešová Radka , Pastucha Dalibor , Horák Vladimír , Dumbrovská Lenka , Martínek Arnošt , Novotný Dalibor , Švagera Zdeněk , Hobzová Milada , Galuszková Dana , Janout Vladimír , Doněvská Sandra , Vrbková Jana , Kollárová Helena
Published: May 2015

The study aimed at assessing the potential use of lower total and HMW adiponectin levels for predicting cardiovascular risk in patients with type 2 diabetes mellitus (T2DM). Concentrations of total adiponectin or high molecular weight (HMW) adiponectin decrease in association with the development of metabolic dysfunction such as obesity, insulin resistance, or T2DM. Increased adiponectin levels are associated with a lower risk for coronary heart disease. A total of 551 individuals were assessed. The first group comprised metabolically healthy participants (143 females, and 126 males) and the second group were T2DM patients (164 females, and 118 males). Both total adiponectin and HMW adiponectin in diabetic patients were significantly lower when compared with the group of metabolically healthy individuals. There was a weak monotonic correlation between HMW adiponectin levels and triglycerides levels. Binary logistic regression analysis, gender adjusted, showed a higher cardiovascular risk in diabetic persons when both total adiponectin (OR = 1.700) and HMW adiponectin (OR = 2.785) levels were decreased. A decrease in total adiponectin levels as well as a decrease in its HMW adiponectin is associated with a higher cardiovascular risk in individuals with T2DM. This association suggests that adiponectin levels may be potentially used as an epidemiological marker for cardiovascular risk in diabetic patients.
Physical Activity Protects the Human Brain against Metabolic Stress Induced by a Postprandial and Chronic Inflammation
Authors: Pruimboom Leo , Raison Charles L. , Muskiet Frits A. J.
Published: May 2015

In recent years, it has become clear that chronic systemic low-grade inflammation is at the root of many, if not all, typically Western diseases associated with the metabolic syndrome. While much focus has been given to sedentary lifestyle as a cause of chronic inflammation, it is less often appreciated that chronic inflammation may also promote a sedentary lifestyle, which in turn causes chronic inflammation. Given that even minor increases in chronic inflammation reduce brain volume in otherwise healthy individuals, the bidirectional relationship between inflammation and sedentary behaviour may explain why humans have lost brain volume in the last 30,000 years and also intelligence in the last 30 years. We review evidence that lack of physical activity induces chronic low-grade inflammation and, consequently, an energy conflict between the selfish immune system and the selfish brain. Although the notion that increased physical activity would improve health in the modern world is widespread, here we provide a novel perspective on this truism by providing evidence that recovery of normal human behaviour, such as spontaneous physical activity, would calm proinflammatory activity, thereby allocating more energy to the brain and other organs, and by doing so would improve human health.
Controllability of Train Service Network
Authors: Meng Xuelei , Xiang Wanli , Wang Li
Published: May 2015

Train service network is a network form of train service plan. The controllability of the train service plan determines the recovery possibility of the train service plan in emergencies. We first build the small-world model for train service network and analyze the scale-free character of it. Then based on the linear network controllability theory, we discuss the LB model adaptability in train service network controllability analysis. The LB model is improved and we construct the train service network and define the connotation of the driver nodes based on the immune propagation and cascading failure in the train service network. An algorithm to search for the driver nodes, turning the train service network into a bipartite graph, is proposed and applied in the train service network. We analyze the controllability of the train service network of China with the method and the results of the computing case prove the feasibility of it.
Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration
Authors: Li Yongle , Dong Shifu , Bao Yulong , Chen Kejian , Qiang Shizhong
Published: May 2015

Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.
Fatigue Performance Assessment of Composite Arch Bridge Suspenders Based on Actual Vehicle Loads
Authors: Chen Bin , Li Xiaozhang , Xie Xu , Zhong Zheng , Lu Pengzhen
Published: May 2015

In the through arch bridges, the suspenders are the key components connecting the arch rib and the bridge deck in the middle, and their safety is an increasing focus in the field of bridge engineering. In this study, various vehicle traffic flow parameters are investigated based on the actual vehicle data acquired from the long-term structural health monitoring system of a composite arch bridge. The representative vehicle types and the probability density functions of several parameters are determined, including the gross vehicle weight, axle weight, time headway, and speed. A finite element model of the bridge structure is constructed to determine the influence line of the cable force for various suspenders. A simulated vehicle flow, generated using the Monte Carlo method, is applied on the influence lines of the target suspender to determine the stress process, and then the stress amplitude spectrum is obtained based on the statistical analysis of the stress process using the rainflow counting method. The fatigue performance levels of various suspenders are analyzed according to the Palmgren-Miner linear cumulative damage theory, which helps to manage the safety of the suspenders.
An EBSPK-/MPPSK-Modem Based Transceiver for Radar-Communications
Authors: Yao Yu , Wu Lenan
Published: May 2015

A joint communication and ranging system would constitute a unique platform for future weapon platform or intelligent transportation system to affect the essential tasks of Identification Friend or Foe (IFF) system and location sharing services, in terms of both spectrum efficiency and cost effectiveness. In this paper, the design of efficient modulation system which is suitable for simultaneously performing both data transmission and range measurement is proposed. The approach is based on extended binary phase shift keying (EBPSK) orM-ary Position Phase Shift Keying (MPPSK) modulated waveforms utilized in digital communication. In particular, requirements that allow for employing such signals for range measurements are investigated. Also, Constant False Alarm Rate (CFAR) target detection performances of the new proposed system are discussed when target velocity and time delay take different values. Moreover, Doppler tolerance range of impacting filter for demodulating EBPSK/MPPSK pulse signal at 10 GHz is considered. In addition to theoretical considerations, the paper presents simulations and measurement results of the new systems, demonstrating the high spectral utilization of integrated communication and ranging applications.
A Wireless Strain Sensor Network for Structural Health Monitoring
Authors: Liu Chengyin , Teng Jun , Wu Ning
Published: May 2015

Structural strain under external environmental loads is one of the main monitoring parameters in structural health monitoring or dynamic tests. This paper presents a wireless strain sensor network (WSSN) design for monitoring structural dynamic strain field. A precision strain sensor board is developed and integrated with the IRIS mote hardware/software platform for multichannel strain gauge signal conditioning and wireless monitoring. Measurement results confirm the sensor’s functionality regarding its static and dynamic characterization. Furthermore, in order to verify the functionality of the designed wireless strain sensor for dynamic strain monitoring, a cluster-star network evaluation system is developed for strain modal testing on an experimental steel truss structure. Test results show very good agreement with the finite element (FE) simulations. This paper demonstrates the feasibility of the proposed WSSN for large structural dynamic strain monitoring.
The Correlation of Serum Growth Differentiation Factor-15 Level in Patients with Obstructive Sleep Apnea
Authors: Sari Kamran , Ede Huseyin , Kapusuz Gencer Zeliha , Ozkiris Mahmut , Gocmen Ayse Yesim , Intepe Yavuz Selim
Published: May 2015

Purpose. Growth differentiation factor-(GDF-) is a prognostic biomarker in cardiovascular disorders (CVD). GDF-15 level was not studied in patients with obstructive sleep apnea syndrome (OSAS) before. In this study, we investigated serum GDF-15 levels in OSAS patients and compared them with healthy controls.Material and Methods. Polysomnographically, confirmed forty consecutive OSAS patients (20 men and 20 women) and forty consecutive healthy controls (23 men and 17 women) were enrolled in the study. The samples in each group had similar demographic characteristics and body mass index (BMI) values.Results. In the study, no significant correlation was found about GDF-15 levels of OSAS group and healthy controls. However, there was a significant statistical correlation between age and GDF-15 level. In correlation analysis, there was not any significant correlation between age and BMI.Conclusion. Although various developing biomarkers have been studied in cardiovascular disorders, GDF-15 levels have attracted a widespread interest as predictors of cardiovascular risk. GDF-15 level has not been evaluated previously in patients with OSAS. A significant statistical correlation was found between age and GDF-15 level. To reveal close relation between OSAS and GDF-15, further studies are needed with combination of GDF-15 and other biomarkers in OSAS.
Detection on Structural Sudden Damage Using Continuous Wavelet Transform and Lipschitz Exponent
Authors: Chen Bo , Kang Yuan-pin , Li Peng-yun , Xie Wen-ping
Published: May 2015

The degradation of civil engineering structures may lead to a sudden stiffness reduction in a structure and such a sudden damage will cause a discontinuity in the dynamic responses. The detection on structural sudden damage has been actively carried out in this study. The signal singularity of the acceleration responses with sudden stiffness reduction is characterized by the coefficients of continuous wavelet transform with fine scales. A detection approach based on the CWT is proposed in terms of the decomposed detail coefficients of continuous wavelet transform to detect the damage time instant and location. The Lipschitz exponent is mathematically used to estimate the local properties of certain function and is applied to reflect the damage severity. Numerical simulation using a five-story shear building under different types of excitation is carried out to assess the validity of the proposed detection approach for the building at different damage levels. The sensitivity of the damage index to the intensity and frequency range of measurement noise is also investigated. The effects of both measurement noise intensity and frequency range on the damage detection are numerically investigated.
Evaluation on Impact Interaction between Abutment and Steel Girder Subjected to Nonuniform Seismic Excitation
Authors: Zheng Yue , Xiao Xiang , Zhi Lunhai , Wang Guobo
Published: May 2015

This paper aims to evaluate the impact interaction between the abutment and the girder subjected to nonuniform seismic excitation. An impact model based on tests is presented by taking material properties of the backfill of the abutment into consideration. The conditional simulation is performed to investigate the spatial variation of earthquake ground motions. A two-span continuous steel box girder bridge is taken as the example to analyze and assess the pounding interaction between the abutment and the girder. The detailed nonlinear finite element (FE) model is established and the steel girder and the reinforced concrete piers are modeled by nonlinear fiber elements. The pounding element of the abutment is simulated by using a trilinear compression gap element. The elastic-perfectly plastic element is used to model the nonlinear rubber bearings. The comparisons of the pounding forces, the shear forces of the nonlinear bearings, the moments of reinforced concrete piers, and the axial pounding stresses of the steel girder are studied. The made observations indicate that the nonuniform excitation for multisupport bridge is imperative in the analysis and evaluation of the pounding effects of the bridges.
Protein Phosphatase 2A Inhibition with LB100 Enhances Radiation-Induced Mitotic Catastrophe and Tumor Growth Delay in Glioblastoma
Authors: Gordon Ira K. , Lu Jie , Graves Christian A. , Huntoon Kristin , Frerich Jason M. , Hanson Ryan H. , Wang Xiaoping , Hong Christopher S. , Ho Winson , Feldman Michael J. , Ikejiri Barbara , Bisht Kheem , Chen Xiaoyuan S. , Tandle Anita , Yang Chunzhang , Arscott W. Tristram , Ye Donald , Heiss John D. , Lonser Russell R. , Camphausen Kevin , Zhuang Zhengping
Published: May 2015

Protein phosphatase 2A (PP2A) is a tumor suppressor whose function is lost in many cancers. An emerging, though counterintuitive, therapeutic approach is inhibition of PP2A to drive damaged cells through the cell cycle, sensitizing them to radiotherapy. We investigated the effects of PP2A inhibition on U251 glioblastoma cells following radiation treatment in vitro and in a xenograft mouse model in vivo. Radiotherapy alone augmented PP2A activity, though this was significantly attenuated with combination LB100 treatment. LB100 treatment yielded a radiation dose enhancement factor of 1.45 and increased the rate of postradiation mitotic catastrophe at 72 and 96 hours. Glioblastoma cells treated with combination LB100 and radiotherapy maintained increased γ-H2AX expression at 24 hours, diminishing cellular repair of radiation-induced DNA double-strand breaks. Combination therapy significantly enhanced tumor growth delay and mouse survival and decreased p53 expression 3.68-fold, compared with radiotherapy alone. LB100 treatment effectively inhibited PP2A activity and enhanced U251 glioblastoma radiosensitivity in vitro and in vivo. Combination treatment with LB100 and radiation significantly delayed tumor growth, prolonging survival. The mechanism of radiosensitization appears to be related to increased mitotic catastrophe, decreased capacity for repair of DNA double-strand breaks, and diminished p53 DNA-damage response pathway activity. Mol Cancer Ther; 14(7); 1540–7. ©2015 AACR.
MEK Inhibition Overcomes Cisplatin Resistance Conferred by SOS/MAPK Pathway Activation in Squamous Cell Carcinoma
Authors: Kong Li Ren , Chua Kian Ngiap , Sim Wen Jing , Ng Hsien Chun , Bi Chonglei , Ho Jingshan , Nga Min En , Pang Yin Huei , Ong Weijie Richard , Soo Ross Andrew , Huynh Hung , Chng Wee Joo , Thiery Jean-Paul , Goh Boon Cher
Published: May 2015

Genomic analyses of squamous cell carcinoma (SCC) have yet to yield significant strategies against pathway activation to improve treatment. Platinum-based chemotherapy remains the mainstay of treatment for SCC of different histotypes either as a single-agent or alongside other chemotherapeutic drugs or radiotherapy; however, resistance inevitably emerges, which limits the duration of treatment response. To elucidate mechanisms that mediate resistance to cisplatin, we compared drug-induced perturbations to gene and protein expression between cisplatin-sensitive and -resistant SCC cells, and identified MAPK–ERK pathway upregulation and activation in drug-resistant cells. ERK-induced resistance appeared to be activated by Son of Sevenless (SOS) upstream, and mediated through Bim degradation downstream. Clinically, elevated p-ERK expression was associated with shorter disease-free survival in patients with locally advanced head and neck SCC treated with concurrent chemoradiation. Inhibition of MEK/ERK, but not that of EGFR or RAF, augmented cisplatin sensitivity in vitro and demonstrated efficacy and tolerability in vivo. Collectively, these findings suggest that inhibition of the activated SOS–MAPK–ERK pathway may augment patient responses to cisplatin treatment. Mol Cancer Ther; 14(7); 1750–60. ©2015 AACR.
Abstract 3425: Whole-transcriptome analyses of EBV-associated nasopharyngeal carcinoma using next-generation transcriptome sequencing
Authors: Mak Cathy Ka-Yan , Chung Grace Tin-Yan , Yip Kevin Yuk-Lap , Tso Ken Kai-Yuen , Lee Sau-Dan , Cheung Siu-Tim , Tsao Sai-Wah , Busson Pierre , To Ka-Fai , Lo Kwok-Wai
Published: May 2015

Nasopharyngeal carcinoma (NPC) is unique among epithelial cancers arising from the head and neck regions. This specific cancer type is consistently associated with EBV infection. Using RNA-seq, we have conducted a comprehensive assessment of EBV and cellular gene expression in six NPC cell line and patient-derived xenografts (PDXs). In these tumor lines, expression of EBV latent genes including EBNA1, LMP1, LMP2A and BamH1 A transcripts was quantitated. Among the viral genes, the BamH1 A transcripts were detected as the major transcripts with various splicing variants. Expression of these transcripts in NPC was further validated by qRT-PCR analysis. Active lytic gene expression and lytic viral replication was not observed in these tumor lines. Analysis of the RNA-seq data has identified multiple fusion transcripts. A total of 18 candidate fusions were validated in these tumor lines. A novel fusion transcript, UBR5-ZNF423 was detected in C666-1 cells and 8.3% of primary tumors. The transcript produces a chimeric fusion protein which might alter the function of EBF transcription factor. A significant growth inhibitory effect was observed in UBR5-ZNF423 knockdown C666-1 cells. Constitutive expression of UBR5-ZNF423 fusion in NIH3T3 cells induced in vivo tumor formation in nude mice model. The findings strongly suggest that the fusion gene play a causative role in NPC tumorigenesis. Using the expression profile of immortalized nasopharyngeal epithelial cells as control, our study also revealed the differential expression of cellular genes and specific alternative spliced transcripts in NPC. Significant upregulation of genes involved in cytokine-cytokine receptor interaction (e.g. CCL5, CCL20, CXCL10, CXCR4, IL2RG) was consistently detected in the tumor lines. Most of them were targets of the NF-kappaB signaling pathways, which are constitutively activated in EBV-associated NPC. In addition, the analyses also discovered several potential druggable targets (e.g. CD74) and oncogenic non-coding RNAs (e.g. AFAP1-AS1) in NPC, which may contribute to the development of new therapeutic strategies for this cancer. The whole-transcriptome analyses greatly enhance our understanding of the molecular basis of EBV-infected NPC.

Citation Format: Cathy Ka-Yan Mak, Grace Tin-Yan Chung, Kevin Yuk-Lap Yip, Ken Kai-Yuen Tso, Sau-Dan Lee, Siu-Tim Cheung, Sai-Wah Tsao, Pierre Busson, Ka-Fai To, Kwok-Wai Lo. Whole-transcriptome analyses of EBV-associated nasopharyngeal carcinoma using next-generation transcriptome sequencing. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3425. doi:10.1158/1538-7445.AM2014-3425
Abstract 3443: Wnt-beta-catenin-Rac1 signaling axis regulates metastasis-associated phenotypes in TNBC
Authors: Dey Nandini , Carlson Jennifer , De Pradip , Leyland-Jones Brian
Published: May 2015

Background: RAC1-GTPase controls many cellular phenotypes including integrin-directed migration via its control over the actin-cytoskeleton. We and others have established the upregulation of Wnt-beta-catenin pathway (WP) in triple negative breast cancer (TNBC), the most aggressive subtype of breast cancer (Dey et al., 2013, BMC Cancer; Dey et al., 2013, PLOS ONE). Here we report for the first time that metastasis-associated phenotypes in TNBC are controlled by Wnt-beta-catenin-RAC1signaling axis. Methodology: The involvement of WP was tested using (1) WP modulators (CHIR99021, Wnt-C59, XAV939), (2) sulindac sulfide and (3) beta-catenin SiRNA. We studied metastasis-associated phenotypes including, (1) proliferation (CelltiterGLO) (2) clonogenic growth (3D On-TOP assay) (3) fibronectin-directed migration (4) matrigel invasion (5) vascular mimicry (6) actin dynamics (confocal-microscopy and podia-parameters) (7) protein expression (WB) (8) real-time imaging for migration and vascular mimicry and (9) adhesion in the context of RAC1 activation in a panel of 3-4 TNBC cell lines. Results: Sulindac sulfide as well as transient transfection of beta-catenin SiRNA (1) decreased cellular levels of beta-catenin, inhibited proliferation, attenuated metastasis-associated different phenotypes and blocked fibronectin-mediated RAC1 as well as Cdc42 activities and (2) altered actin dynamics and inhibited podia-parameters (lamellopodia and fillopodia). Both Wnt-antagonists and RAC1 inhibitor (NSC23766) blocked fibronectin-induced RAC1 activation and inhibited the metastasis-associated phenotypes, while Wnt-activator enhanced phenotypes like vascular mimicry. Conclusion: Results of our experiments show that upregulation of WP regulates metastasis-associated phenotypes in TNBC via activation of RAC1 GTP-ase. The functional link between WP, metastasis and the activation of RAC1 is being currently worked out using RAC1SiRNA and pharmacological inhibitor of RAC1 in brain metastasizing MDA-MB231BR cells to specifically address the role of Wnt-beta-catenin-RAC1 signaling axis in the context of distant metastasis, the results of which will be presented at the meeting.

Citation Format: Nandini Dey, Jennifer Carlson, Pradip De, Brian Leyland-Jones. Wnt-beta-catenin-Rac1 signaling axis regulates metastasis-associated phenotypes in TNBC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3443. doi:10.1158/1538-7445.AM2014-3443