bluuebunny/crossref_metadata_2025 huggingface dataset:
Postbuckling of Unknown-Length Nanobeam Considering the Effects of Nonlocal Elasticity and Surface Stress
Authors: Thongyothee Chawis , Chucheepsakul Somchai
Published: June 2015

The objective of this paper is to study the postbuckling behaviors of an unknown-length nanobeam combined with small-scale effects. The concept of variable-arc-length elastica is firstly applied on the problem of nanobeams. The span length is not changed while the arc length is varied increasingly. The nanobeam is on a clamped support at one end, while the other end is an overhanging part through a frictionless slot subjected to axial compression. At this end, the nanobeam is movable only in a horizontal direction. The governing equation is developed by the moment–curvature relationship based on the classical Euler–Bernoulli beam theory, including the effects of nonlocal elasticity, residual surface stress, and both combined effects. The shooting–optimization technique with two-point boundary condition is employed to solve the differential equations in this problem. The results, including nonlocal elasticity, reveal that nanobeams have decreased structural stiffness; meanwhile, the residual surface tension and both combined effects have increased strength. The postbuckling loads decrease as the arc length of nanobeams is increased. The equilibrium configurations are close to an anti-loop for very large deflections. The friction force at the nanoslot is also considered.
A Novel Morphological Model of Trabecular Bone Based on the Gyroid
Authors: Rammohan Abhishek Vishwanath , Lee Taeyong , Tan V. B. C.
Published: June 2015

Human trabecular bone is known to be structurally very complex. The geometrical distribution of trabecular bone has major effects on its ability to perform its physiological function of load-bearing efficiently. Idealized unit cell models are very helpful in understanding the significance of micro-level properties on macro-level behavior. There is a need for a simple method to model trabecular bone, such that micro-level phenomena (like buckling) can be studied. We investigate a new model for trabecular bone, based on a minimal surface solid called a gyroid. The gyroid-based model is computationally easy to implement, and generates structures that possess strong morphometric and mechanical resemblance to real trabecular bone. We generated gyroid models for a range of volume fractions, representing trabecular bone samples obtained from various anatomic sites and ages. Finite element analysis was performed to obtain the mechanical properties of the gyroid structures. We calculated the small-strain elastic moduli values for each of the gyroid models and plotted these against corresponding apparent density. A power-law relationship was obtained for the gyroid models, in accordance with published studies on real trabecular bone mechanical behavior. The results showed that the gyroid could provide a suitable model for studying the effects of variations in trabecular structure on macro-level bone behavior.
Analytical Solution for Free Vibration of Laminated Curved Beam with Magnetostrictive Layers
Authors: Bayat R. , Jafari A. A. , Rahmani O.
Published: June 2015

An analytical model to study the free vibration suppression of laminated curved beam with embedded actuating layers is presented in this study. The magnetostrictive layers are used to control and enhance the vibration suppression. The governing differential equations of the model are derived using the Hamilton principle. Analytical solution of the equations governing laminated curved beam with embedded magnetostrictive layers are obtained for simply-supported boundary conditions. Velocity feedback with constant gain distributed controller, by using Terfenol-D as smart material, is chosen to achieve vibration suppression. The effects of material properties, radius of curvature, lamination scheme, and placement of magnetostrictive layers with respect to laminate midplane on vibration suppression are studied in details.
A function field analogue of Romanoff's theorem
Authors: Kuan Yen-Liang
Published: June 2015

We prove an analogue for Drinfeld modules of a theorem of Romanoff. Specifically, let ϕ be a Drinfeld A-module over a global function field L and denote by ϕ(L) the A-module structure on L coming from ϕ. Let Γ ⊂ ϕ (L) be a free A-submodule of finite rank. For each effective divisor [Formula: see text] of L, let fΓ(𝔇) be the cardinality of the image of the reduction map [Formula: see text] if all elements of Γ are relatively prime to the divisor 𝔇; otherwise, just set fΓ(𝔇) = ∞. We give explicit upper bounds for the series [Formula: see text] and [Formula: see text].
The use of seismic attributes for fan and reservoir definition in the Sea Lion Field, North Falkland Basin
Authors: Bunt Richard J. W.
Published: June 2015

Fan bodies in the North Falkland Basin, including those that comprise the reservoir in the Sea Lion Field, have been defined seismically with the aid of several seismic attributes. This has provided a greater understanding of their geomorphology, potential reservoir variations and distribution, and has helped illuminate the full extent of some fans as well as the internal architectural detail of others. The attributes used include reflectivity attributes on full-stack and part-stack three-dimensional (3D) seismic data, impedance attributes on inverted seismic data, isochron attributes, and geometric attributes such as coherence, dip, curvature and spectral decomposition. The combination of spectral decomposition and high-resolution visualization techniques has greatly aided the identification and interpretation of some of the fans. Colour blending, where separate colours relating to different frequency ranges are blended into a single image, can reveal additional detail within the fan systems. Specific colour blends are seen to highlight separate sand bodies, as well as thickness variations, and have helped to resolve stratigraphic and petrophysical heterogeneity. Seismic attribute responses have been quantified with the integration of well data from the 18 wells within the 3D data set. This has resulted in a detailed reservoir characterization and definition of geological features within some of the fan bodies. This detailed use of seismic attributes on the North Falkland Basin 3D data set has been of benefit for both the appraisal and development of the Sea Lion Field, and has also helped to define future exploration targets and well locations within the basin.
The RGD sequence present in IGFBP-2 is required for reduced glucose clearance after oral glucose administration in female transgenic mice
Authors: Reyer Anja , Schindler Nancy , Ohde Daniela , Walz Christina , Kunze Martin , Tuchscherer Armin , Wirthgen Elisa , Brenmoehl Julia , Hoeflich Andreas
Published: June 2015

Recent studies suggest that insulin-like growth factor-binding protein-2 (IGFBP-2) affects both growth and metabolism. Whereas negative growth effects are primarily due to negative interference with IGF-I, the mechanisms for metabolic interference of IGFBP-2 are less clear. As we demonstrate, overexpression of IGFBP-2 in transgenic mice is correlated with a decelerated clearance of blood glucose after oral administration. IGFBP-2 carries an integrin-binding domain (RGD motif), which has been shown to also mediate IGF-independent effects. We thus asked if higher serum levels of IGFBP-2 without an intact RGD motif would also partially block blood glucose clearance after oral glucose application. In fact, transgenic mice overexpressing mutated IGFBP-2 with higher levels of IGFBP-2 carrying an RGE motif instead of an RGD were not characterized by decelerated glucose clearance. Impaired glucose tolerance was correlated with lower levels of GLUT4 present in plasma membranes isolated from muscle tissues after glucose challenge. At the same time, activation of TBC1D1 was depressed in mice overexpressing wild-type but not mutated IGFBP-2. Although we do not have reason to assume altered activation of IGF-I receptor or PDK1/Akt activation in both models, we have identified increased levels of integrin-linked kinase and focal adhesion kinase dependent on the presence of the RGD motif. From our results we conclude that impaired glucose clearance in female IGFBP-2 transgenic mice is dependent on the presence of the RGD motif and that translocation of GLUT4 in the muscle may be regulated by IGFBP-2 via RGD-dependent mechanisms.
MicroRNA-150 deletion in mice protects kidney from myocardial infarction-induced acute kidney injury
Authors: Ranganathan Punithavathi , Jayakumar Calpurnia , Tang Yaoping , Park Kyoung-mi , Teoh Jian-peng , Su Huabo , Li Jie , Kim Il-man , Ramesh Ganesan
Published: June 2015

Despite greater understanding of acute kidney injury (AKI) in animal models, many of the preclinical studies are not translatable. Most of the data were derived from a bilateral renal pedicle clamping model with warm ischemia. However, ischemic injury of the kidney in humans is distinctly different and does not involve clamping of renal vessel. Permanent ligation of the left anterior descending coronary artery model was used to test the role of microRNA (miR)-150 in AKI. Myocardial infarction in this model causes AKI which is similar to human cardiac bypass surgery. Moreover, the time course of serum creatinine and biomarker elevation were also similar to human ischemic injury. Deletion of miR-150 suppressed AKI which was associated with suppression of inflammation and interstitial cell apoptosis. Immunofluorescence staining with endothelial marker and marker of apoptosis suggested that dying cells are mostly endothelial cells with minimal epithelial cell apoptosis in this model. Interestingly, deletion of miR-150 also suppressed interstitial fibrosis. Consistent with protection, miR-150 deletion causes induction of its target gene insulin-like growth factor-1 receptor (IGF-1R) and overexpression of miR-150 in endothelial cells downregulated IGF-1R, suggesting miR-150 may mediate its detrimental effects through suppression of IGF-1R pathways.
Ketamine-induced ulcerative cystitis and bladder apoptosis involve oxidative stress mediated by mitochondria and the endoplasmic reticulum
Authors: Liu Keh-Min , Chuang Shu-Mien , Long Cheng-Yu , Lee Yi-Lun , Wang Chao-Chuan , Lu Mei-Chin , Lin Rong-Jyh , Lu Jian-He , Jang Mei-Yu , Wu Wen-Jeng , Ho Wan-Ting , Juan Yung-Shun
Published: June 2015

Ketamine abusers develop severe lower urinary tract symptoms. The major aims of the present study were to elucidate ketamine-induced ulcerative cystitis and bladder apoptosis in association with oxidative stress mediated by mitochondria and the endoplasmic reticulum (ER). Sprague-Dawley rats were distributed into three different groups, which received normal saline or ketamine for a period of 14 or 28 days, respectively. Double-labeled immunofluorescence experiments were performed to investigate tight junction proteins for urothelial barrier functions. A TUNEL assay was performed to evaluate the distribution of apoptotic cells. Western blot analysis was carried out to examine the expressions of urothelial tight junction proteins, ER stress markers, and apoptosis-associated proteins. Antioxidant enzymes, including SOD and catalase, were investigated by real-time PCR and immunofluorescence experiments. Ketamine-treated rats were found to display bladder hyperactivity. This bladder dysfunction was accompanied by disruptions of epithelial cadherin- and tight junction-associated proteins as well as increases in the expressions of apoptosis-associated proteins, which displayed features of mitochondria-dependent apoptotic signals and ER stress markers. Meanwhile, expressions of mitochondria respiratory subunit enzymes were significantly increased in ketamine-treated bladders. Conversely, mRNA expressions of the antioxidant enzymes Mn-SOD (SOD2), Cu/Zn-SOD (SOD1), and catalase were decreased after 28 days of ketamine treatment. These results demonstrate that ketamine enhanced the generation of oxidative stress mediated by mitochondria- and ER-dependent pathways and consequently contributed to bladder apoptosis and urothelial lining defects. Such oxidative stress-enhanced bladder cell apoptosis and urothelial barrier defects are potential factors that may play a crucial role in bladder overactivity and ulceration.
Properties of Neutron Noise Induced by Localized Perturbations in an SFR
Authors: Tran Hoai-Nam
Published: June 2015

Investigation of the properties of neutron noise induced by localized perturbations in a sodium-cooled fast reactor has been performed using a multigroup neutron noise simulator. Three representations of the noise source associated with the perturbations of absorption, fission, and scattering cross sections, respectively, were assumed to be located at the first fuel ring around the central assembly. The energy- and space-dependent noise, that is, the amplitude and the phase, was calculated in a wide range of frequencies, for example, 0.1–100 Hz. The results show that in the important energy range (>1.0 keV) where the noise amplitude is significant the phase is almost constant with energy at the calculated frequencies despite the source types. At low frequencies, the variation of the phase is negligibly small at a large distance from the source. The perturbation in several fast groups has a significant contribution and dominates the amplitude and the phase of the induced noise.
A Flexible Modulation Scheme Design for C-Band GNSS Signals
Authors: Xue Rui , Cao Qing-ming , Wei Qiang
Published: June 2015

Due to the spectrum congestion of current navigation signals in L-band, C-band has been taken into consideration as a candidate frequency band for global navigation satellite system (GNSS). As is known, modulation scheme is the core part of signal structure, and how to design a modulation waveform that could make full use of narrow bandwidth 20 MHz and satisfy the constraint condition of frequency compatibility in C-band is the main research content of this paper. In view of transmission characteristics and constraint condition of compatibility in C-band, multi-hcontinuous phase modulation (CPM) is proposed as a candidate modulation scheme. Then the classical channel capacity estimation and a comprehensive evaluation criterion for GNSS modulation signals are employed to assess the proposed scheme in the aspects of the capacity over additive white Gaussian noise (AWGN), tracking accuracy, multipath mitigation, antijamming, and so on. Simulation results reveal that, through optimizing the number and size of modulation indexes, the flexible scheme could offer better performance in terms of code tracking, multipath mitigation, and antijamming compared with other candidates such as MSK and GMSK while maintaining high band efficiency and moderate implementation complexity of receiver. Moreover, this paper also provides a reference for next generation modulation signals in C-band.
Numerical Study of Correlation of Fluid Particle Acceleration and Turbulence Intensity in Swirling Flow
Authors: Gui Nan , Yang Xingtuan , Yan Jie , Tu Jiyuan , Jiang Shengyao
Published: June 2015

Numerical investigation of correlation between the fluid particle acceleration and the intensity of turbulence in swirling flows at a large Reynolds number is carried out via direct numerical simulation. A weak power-law form correlationur.m.sE~C(aL)φbetween the Lagrangian acceleration and the Eulerian turbulence intensity is derived. It is found that the increase of the swirl level leads to the increase of the exponentφand the trajectory-conditioned correlation coefficientρ(aL,uE)and results in a weak power-law augmentation of the acceleration intermittency. The trajectory-conditioned convection of turbulence fluctuation in the Eulerian viewpoint is generally linearly proportional to the fluctuation of Lagrangian accelerations, indicating a weak but clear relation between the Lagrangian intermittency and Eulerian intermittency effects. Moreover, except the case with vortex breakdown, the weak linear dependency is maintained when the swirl levels change, only with the coefficient of slope varied.
Drag Reduction in Turbulent Boundary Layers with Half Wave Wall Oscillations
Authors: Mishra Maneesh , Skote Martin
Published: June 2015

Spatial square waves with positive cycle are used as steady forcing technique to study drag reduction effects on a turbulent boundary layer flow. Pseudospectral method is used for performing direct numerical simulations on very high resolution grids. A smooth step function is employed to prevent Gibbs phenomenon at the sharp discontinuities of a square wave. The idea behind keeping only the positive cycle of the spatial forcing is to reduce the power consumption to boost net power savings. For some spatial frequency of the oscillations with half waves, it is possible to prevent recovery of skin friction back to the reference case values. A set of wall oscillation parameters is numerically simulated to study its effect on the power budget.
Optimization ofμc-Si1−xGex:H Single-Junction Solar Cells with Enhanced Spectral Response and Improved Film Quality
Authors: Huang Yen-Tang , Chen Pei-Ling , Chen Po-Wei , Hsu Hung-Jung , Hsu Cheng-Hang , Tsai Chuang-Chuang
Published: June 2015

Effects of RF power on optical, electrical, and structural properties ofμc-Si1−xGex:H films was reported. Raman and FTIR spectra fromμc-Si1−xGex:H films reflected the variation in microstructure and bonding configuration. Unlike increasing the germane concentration for Ge incorporation, low RF power enhanced Ge incorporation efficiency inμc-Si1−xGex:H alloy. By decreasing RF power from 100 to 50 W at a fixed reactant gas ratio, the optical bandgap ofμc-Si1−xGex:H was reduced owing to the increase in Ge content from 11.2 to 23.8 at.%, while Ge-related defects and amorphous phase were increased. Consequently, photo conductivity of 1.62 × 10−5 S/cm was obtained for theμc-Si1−xGex:H film deposited at 60 W. By applying 0.9 μm thickμc-Si1−xGex:H absorber withXCof 48% and [Ge] of 16.4 at.% in the single-junction cell, efficiency of 6.18% was obtained. The long-wavelength response ofμc-Si1−xGex:H cell was significantly enhanced compared with theμc-Si:H cell. In the case of tandem cells, 0.24 μm a-Si:H/0.9 μmμc-Si1−xGex:H tandem cell exhibited a comparable spectral response as 0.24 μm a-Si:H/1.4 μmμc-Si:H tandem cell and achieved an efficiency of 9.44%.
Undersampled MR Image Reconstruction with Data-Driven Tight Frame
Authors: Liu Jianbo , Wang Shanshan , Peng Xi , Liang Dong
Published: June 2015

Undersampled magnetic resonance image reconstruction employing sparsity regularization has fascinated many researchers in recent years under the support of compressed sensing theory. Nevertheless, most existing sparsity-regularized reconstruction methods either lack adaptability to capture the structure information or suffer from high computational load. With the aim of further improving image reconstruction accuracy without introducing too much computation, this paper proposes a data-driven tight frame magnetic image reconstruction (DDTF-MRI) method. By taking advantage of the efficiency and effectiveness of data-driven tight frame, DDTF-MRI trains an adaptive tight frame to sparsify the to-be-reconstructed MR image. Furthermore, a two-level Bregman iteration algorithm has been developed to solve the proposed model. The proposed method has been compared to two state-of-the-art methods on four datasets and encouraging performances have been achieved by DDTF-MRI.
An EM Modeling for Rescue System Design of Buried People
Authors: De Leo A. , Petrini V. , Russo P. , Scalise L. , Di Mattia V. , Primiani Valter Mariani , Cerri G.
Published: June 2015

The development of a rescue system for buried persons is a subject of growing importance in case of occurrence of natural disasters such as earthquake, landslides, or avalanches. In this paper a fully analytical model has been developed to get some fundamental a priori design characteristics. The proposed system is based on the detection of the victim movements due to its respiratory activity: in particular, when an electromagnetic (EM) wave impinges on a human body, the analysis of the reflected wave parameters such as amplitude, frequency, phase, or delay time allows for the detection of the breathing frequency. The model is simple on purpose because the great uncertainty concerning the characterization of many environmental parameters of a general situation makes a very detailed model useless. However, it is accurate enough to provide useful information about system design, filling the gap in the literature concerning the electromagnetic formulation of such kinds of problems. A system prototype was built using laboratory equipment to experimentally validate the model, and subsequently breathing frequency measurements were carried on, both in a lossless laboratory environment and in a lossy realistic scenario.
An Investigation of Wavelet Average Framing LPC for Noisy Speaker Identification Environment
Authors: Daqrouq Khaled , Al-Hmouz Rami , Balamash Abdullah Saeed , Alotaibi Naif , Noeth Elmar
Published: June 2015

In the presented research paper, an average framing linear prediction coding (AFLPC) method for a text-independent speaker identification system is studied. AFLPC was proposed in our previous work. Generally, linear prediction coding (LPC) has been used in numerous speech recognition tasks. Here, an investigative procedure was based on studying the AFLPC speaker recognition system in a noisy environment. In the stage of feature extraction, the speaker-specific resonances of the vocal tract were extracted using the AFLPC technique. In the phase of classification, a probabilistic neural network (PNN) and Bayesian classifier (BC) were applied for comparison. In the performed investigation, the quality of different wavelet transforms with AFLPC techniques was compared with each other. In addition, the capability analysis of the proposed system was examined for comparison with other systems suggested in the literature. In response to an achieved experimental result in a noisy environment, the PNN classifier could have a better performance with the fusion of wavelets and AFLPC as a feature extraction technique termed WFALPCF.
A Partial Lagrangian Approach to Mathematical Models of Epidemiology
Authors: Naz R. , Naeem I. , Mahomed F. M.
Published: June 2015

This paper analyzes the first integrals and exact solutions of mathematical models of epidemiology via the partial Lagrangian approach by replacing the three first-order nonlinear ordinary differential equations by an equivalent system containing one second-order equation and a first-order equation. The partial Lagrangian approach is then utilized for the second-order ODE to construct the first integrals of the underlying system. We investigate the SIR and HIV models. We obtain two first integrals for the SIR model with and without demographic growth. For the HIV model without demography, five first integrals are established and two first integrals are deduced for the HIV model with demography. Then we utilize the derived first integrals to construct exact solutions to the models under investigation. The dynamic properties of these models are studied too. Numerical solutions are derived for SIR models by finite difference method and are compared with exact solutions.
Linear Feedback Synchronization Used in the Three-Dimensional Duffing System
Authors: Han Jian-qun , Shi Xu-dong , Sun Hong
Published: June 2015

It has been realized that synchronization using linear feedback control method is efficient compared to nonlinear feedback control method due to the less computational complexity and the synchronization error. For the problem of feedback synchronization of Duffing chaotic system, in the paper, we firstly established three-dimensional Duffing system by method of variable decomposition and, then, studied the synchronization of Duffing chaotic system and designed the control law based on linear feedback control and Lyapunov stability theory. It is proved theoretically that the two identical integer order chaotic systems are synchronized analytically and numerically.
The Impact of Immunosenescence on Pulmonary Disease
Authors: Murray Michelle A. , Chotirmall Sanjay H.
Published: June 2015

The global population is aging with significant gains in life expectancy particularly in the developed world. Consequently, greater focus on understanding the processes that underlie physiological aging has occurred. Key facets of advancing age include genomic instability, telomere shortening, epigenetic changes, and declines in immune function termed immunosenescence. Immunosenescence and its associated chronic low grade systemic “inflamm‐aging” contribute to the development and progression of pulmonary disease in older individuals. These physiological processes predispose to pulmonary infection and confer specific and unique clinical phenotypes observed in chronic respiratory disease including late‐onset asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. Emerging concepts of the gut and airway microbiome further complicate the interrelationship between host and microorganism particularly from an immunological perspective and especially so in the setting of immunosenescence. This review focuses on our current understanding of the aging process, immunosenescence, and how it can potentially impact on various pulmonary diseases and the human microbiome.
Phytofabrication of Bioactive Molecules Encapsulated Metallic Silver Nanoparticles from Cucumis sativus L. and Its Enhanced Wound Healing Potential in Rat Model
Authors: Venkatachalam Perumal , Sangeetha Palanivel , Geetha Natesan , Sahi Shivendra Vikram
Published: June 2015

The present study describes a rapid method for synthesis of metallic silver nanoparticles using callus (CAgNPs) and leaf extracts (LEAgNPs) of Cucumis sativus and evaluation of its wound healing activity in rat model. The prepared silver nanoparticles showed a peak at 350 nm corresponding to the surface plasmon resonance band. The FTIR spectroscopy measurements showed the presence of the possible biomolecules. X‐ray diffraction analysis confirmed the crystalline structure of the synthesized silver nanoparticles. TEM images showed the size of the synthesized CAgNPs with diameter ranged from 21 nm to 23 nm with polygonal shape whereas, in the case of LEAgNPs, spherical shape was noticed with an average size between 11 nm and 19 nm. The EDX results indicated the chemical composition at specific locations on synthesized nanoparticles. Furthermore the topical application of ointment prepared using synthesized AgNPs was found to show enhanced wound healing activity in Wistar albino rat model. By the 21st day, the ointment base containing 5% (w/w) of silver nanoparticles showed 100% potential wound healing activity than the standard drug as well as control bases. Results strongly showed that the ointment base containing LEAgNPs was found to be very effective in wound repair mechanism in the experimental rats.
Fibrosis Related Inflammatory Mediators: Role of the IL‐10 Cytokine Family
Authors: Sziksz Erna , Pap Domonkos , Lippai Rita , Béres Nóra Judit , Fekete Andrea , Szabó Attila J. , Vannay Ádám
Published: June 2015

Importance of chronic fibroproliferative diseases (FDs) including pulmonary fibrosis, chronic kidney diseases, inflammatory bowel disease, and cardiovascular or liver fibrosis is rapidly increasing and they have become a major public health problem. According to some estimates about 45% of all deaths are attributed to FDs in the developed world. Independently of their etiology the common hallmark of FDs is chronic inflammation. Infiltrating immune cells, endothelial, epithelial, and other resident cells of the injured organ release an orchestra of inflammatory mediators, which stimulate the proliferation and excessive extracellular matrix (ECM) production of myofibroblasts, the effector cells of organ fibrosis. Abnormal amount of ECM disturbs the original organ architecture leading to the decline of function. Although our knowledge is rapidly expanding, we still have neither a diagnostic tool to detect nor a drug to specifically target fibrosis. Therefore, there is an urgent need for the more comprehensive understanding of the pathomechanism of fibrosis and development of novel diagnostic and therapeutic strategies. In the present review we provide an overview of the common key mediators of organ fibrosis highlighting the role of interleukin‐10 (IL‐10) cytokine family members (IL‐10, IL‐19, IL‐20, IL‐22, IL‐24, and IL‐26), which recently came into focus as tissue remodeling‐related inflammatory cytokines.
Synthesis of Adaptive Gain Robust Controllers for Polytopic Uncertain Systems
Authors: Oya Hidetoshi , Yamasaki Daisuke , Nagai Shunya , Hagino Kojiro
Published: June 2015

We present a new adaptive gain robust controller for polytopic uncertain systems. The proposed adaptive gain robust controller consists of a state feedback law with a fixed gain and a compensation input with adaptive gains which are tuned by updating laws. In this paper, we show that sufficient conditions for the existence of the proposed adaptive gain robust controller are given in terms of LMIs. Finally, illustrative examples are presented to show the effectiveness of the proposed adaptive gain robust controller.
Shape Preserving Data Interpolation Using Rational Cubic Ball Functions
Authors: Tahat Ayser Nasir Hassan , Piah Abd Rahni Mt , Yahya Zainor Ridzuan
Published: June 2015

A smooth curve interpolation scheme for positive, monotone, and convex data is developed. This scheme uses rational cubic Ball representation with four shape parameters in its description. Conditions of two shape parameters are derived in such a way that they preserve the shape of the data, whereas the other two parameters remain free to enable the user to modify the shape of the curve. The degree of smoothness isC1. The outputs from a number of numerical experiments are presented.
Assembly of Optimum Habitats for Asian Houbara Bustard (Chlamydotis macqueenii) in the Arabian Peninsula: The Vegetation Aspects
Authors: Asadalla Naseraldeen Baqer , Abido Mohammad Sulaiman , Abahussain Asma , Shobrak Mohamed
Published: June 2015

This research was conducted in four sites at Mahazat as-Sayd reserve in Saudi Arabia to determine the optimum habitats’ constituents for Asian houbara bustardChlamydotis macqueeniivia assessing abiotic and biotic factors with special reference to vegetation aspects. Vegetative parameters were quantified using combinations of distance and line intercept methods. Acquired data were analyzed using cluster analysis and analysis of variance tests. Results indicated that three of the four plant communities of the study sites were dominated byAcacia tortiliswith underground cover composed of lesser species. On the other hand, White Jabal was dominated by scrubs composed mainly ofFagonia indicawith sparse Acacia trees. Rumrumiyya site recorded the highest species abundance and vegetative coverage (133%) among the sites. It is concluded that Black Jabal and White Jabal sites are used as nesting and foraging habitats for houbaras, whereas Jabal Khurse is specifically a males’ display site. Nevertheless, Rumrumiyya site was used for foraging and shelter. The study confirmed that density and vegetation cover are of prime importance for houbara site selection. However, other factors affecting feeding and behavior of the species must be considered in further studies.
Clutter Mitigation in Echocardiography Using Sparse Signal Separation
Authors: Turek Javier S. , Elad Michael , Yavneh Irad
Published: June 2015

In ultrasound imaging, clutter artifacts degrade images and may cause inaccurate diagnosis. In this paper, we apply a method called Morphological Component Analysis (MCA) for sparse signal separation with the objective of reducing such clutter artifacts. The MCA approach assumes that the two signals in the additive mix have each a sparse representation under some dictionary of atoms (a matrix), and separation is achieved by finding these sparse representations. In our work, an adaptive approach is used for learning the dictionary from the echo data. MCA is compared to Singular Value Filtering (SVF), a Principal Component Analysis- (PCA-) based filtering technique, and to a high-pass Finite Impulse Response (FIR) filter. Each filter is applied to a simulated hypoechoic lesion sequence, as well as experimental cardiac ultrasound data. MCA is demonstrated in both cases to outperform the FIR filter and obtain results comparable to the SVF method in terms of contrast-to-noise ratio (CNR). Furthermore, MCA shows a lower impact on tissue sections while removing the clutter artifacts. In experimental heart data, MCA obtains in our experiments clutter mitigation with an average CNR improvement of 1.33 dB.
Upregulation of Death Receptor 5 and Production of Reactive Oxygen Species Mediate Sensitization of PC-3 Prostate Cancer Cells to TRAIL Induced Apoptosis by Vitisin A
Authors: Shin Deokil , Kwon Hee-Young , Sohn Eun Jung , Nam Moon Sik , Kim Jung Hyo , Lee Jae Chul , Ryu Shi-Yong , Park Byungchun , Kim Sung-Hoon
Published: June 2015

Background/Aims: Although Vitisin A, derived from wine grapes, is known to have cytotoxic, anti-adipogenic, anti-inflammatory and antioxidant effects, the underlying antitumor mechanism has not been investigated in prostate cancer cells to date. In the present study, the apoptotic mechanism of Vitisin A plus TNF-related apoptosis-inducing ligand (TRAIL) in prostate cancer cells was elucidated. Methods: The cytotoxicity of Vitisin A and/or TRAIL against PC-3, DU145 and LNCaP prostate cancer cells was measured by MTT colorimetric assay. Annexin V-FITC Apoptosis Detection kit was used to detect apoptotic cells by flow cytometry. Intracellular levels of ROS were measured by flow cytometry using 2070-diacetyl dichlorofluorescein (DCFDA). Results: Combined treatment with Vitisin A and TRAIL enhanced cytotoxicity and also increased sub-G1 population in PC-3 cells better than DU145 or LNCap prostate cancer cells. Similarly, Annexin V and PI staining revealed that combination increased early and late apoptosis in PC-3 cells compared to untreated control. Consistently, combination attenuated the expression of pro-caspases 7/8, DcR1, Bcl-XL or Bcl-2 and activated caspase 3, FADD, DR5 and DR4 in PC-3 cells. Also, combination increased DR5 promoter activity compared to untreated control. Furthermore, combination increased the production of reactive oxygen species (ROS) and DR5 cell surface expression. The ROS inhibitor NAC and silencing of DR5 by siRNA transfection inhibited the ability of combination to induce PARP cleavage and generate ROS. Conclusion: These findings provide evidence that Vitisin A can be used in conjunction with TRAIL as a potent TRAIL sensitizer for synergistic apoptosis induction via upregulation of DR5 and production of ROS in prostate cancer cells.
Adam17, a Target of Mir-326, Promotes Emt-Induced Cells Invasion in Lung Adenocarcinoma
Authors: Cai Ming , Wang Zhiqiang , Zhang Jiru , Zhou Huan , Jin Linfang , Bai Ruizhen , Weng Yuan
Published: June 2015

Background/Aims: A disintegrin and metalloprotease (ADAM) 17 has been reported to be implicated in cancer cells invasion. Nevertheless, its potential role in lung adenocarcinoma has not been addressed clearly. Methods: RT-PCR and Western blot were used to detect the expression of miR-326 and ADAM17 in lung adenocarcinoma samples (n=73). miR-326 mimics and inhibitor were tansfected in human A549 and SPCA1 cell lines. The transwell assay was used to detect the cell invasive ability. The regulation mechanism was evaluated by luciferase reporter assay. The markers of (epithelial-to-mesenchymal transition) EMT were detected by using Western blot assay. Results: We found increased expression of ADAM17 in lung adenocarcinoma and cell lines. In vitro, up-regulation of ADAM17 promoted cells invasion, while silencing of ADAM17 inhibited cells invasion. Meanwhile, ADAM17 could affect the markers of EMT. Furthermore, we confirmed that ADAM17 is a target of miR-326, which is involved in EMT and cells invasion. Conclusions: These findings revealed that ADAM17, a target of miR-326, promoted EMT-induced cells invasion in lung adenocarcinoma.
Influence of Lentiviral β-Synuclein Overexpression in the Hippocampus of a Transgenic Mouse Model of Alzheimer's Disease on Amyloid Precursor Protein Metabolism and Pathology
Authors: Krassnig Stefanie , Schweinzer Cornelia , Taub Nicole , Havas Daniel , Auer Ewald , Flunkert Stefanie , Schreibmayer Wolfgang , Hutter-Paier Birgit , Windisch Manfred
Published: June 2015

Background: β-Synuclein (β-Syn) is a member of the highly homologous synuclein protein family. The most prominent family member, α-synuclein (α-Syn), abnormally accumulates in so-called Lewy bodies, one of the major pathological hallmarks of α-synucleinopathies. Notably, parts of the peptide backbone, called the nonamyloid component, are also found in amyloid plaques. However, β-Syn seems to have beneficial effects by reducing α-Syn aggregation, and amyloid antiaggregatory activity has been described. Objective: The aim of the study was to analyze if wild-type β-Syn can counteract functional and pathological changes in a murine Alzheimer model over different time periods. Methods: At the onset of pathology, lentiviral particles expressing human β-Syn were injected into the hippocampus of transgenic mice overexpressing human amyloid precursor protein with Swedish and London mutations (APPSL). An empty vector served as the control. Behavioral analyses were performed 1, 3 and 6 months after injection followed by biochemical and histological examinations of brain samples. Results: β-Syn expression was locally concentrated and rather modest, but nevertheless changed its effect on APP expression and plaque load in a time- and concentration-dependent manner. Interestingly, the phosphorylation of glycogen synthase kinase 3 beta was enhanced in APPSL mice expressing human β-Syn, but an inverse trend was observed in wild-type animals. Conclusion: The initially reported beneficial effects of β-Syn could be partially reproduced, but locally elevated levels of β-Syn might also cause neurodegeneration. To enlighten the controversial pathological mechanism of β-Syn, further examinations considering the relationship between concentration and exposure time of β-Syn are needed.
Myocardial Function by Two-Dimensional Speckle Tracking Echocardiography and Activin A May Predict Mortality in Patients with Carcinoid Intestinal Disease
Authors: Zahid Wasim , Bergestuen Deidi , Haugaa Kristina H. , Ueland Thor , Thiis-Evensen Espen , Aukrust Pål , Fosse Erik , Edvardsen Thor
Published: June 2015

Objectives: Myocardial fibrosis causes deterioration of myocardial function in carcinoid intestinal disease (CID). We assessed the ability of myocardial function and various biomarkers to predict mortality in patients with CID. Methods: A total of 71 patients with small intestinal carcinoid tumours were included, and underwent echocardiography at baseline. Systolic function was assessed by two-dimensional speckle tracking echocardiography as left ventricular (LV) and right ventricular (RV) strain, and as mitral annular displacement (MAD), by tissue Doppler imaging. Parameters of diastolic function, the amount of liver metastases, and various biomarkers were also analysed. Results: During 1,274 ± 368 days of follow-up, 18 patients (25%) died. Of the 53 survivors, 46 patients (87%) were available for follow-up echocardiography. Baseline LV strain and MAD was reduced in those who died compared to those who survived (p < 0.001). Baseline plasma levels of activin A were markedly higher in patients who died during follow-up than those who survived (p = 0.001). In multivariate Cox hazard models (A, B, C and D), LV strain, age, the amount of liver metastases, MAD, and activin A were independent predictors of mortality. Conclusion: Assessment of myocardial function by echocardiography, and the biomarker activin A, can be very useful in the risk stratification of patients with CID.
Chromosome Banding in Amphibia. XXXII. The Genus Xenopus (Anura, Pipidae)
Authors: Schmid Michael , Steinlein Claus
Published: June 2015

Mitotic chromosomes of 16 species of the frog genus Xenopus were prepared from kidney and lung cell cultures. In the chromosomes of 7 species, high-resolution replication banding patterns could be induced by treating the cultures with 5-bromodeoxyuridine (BrdU) and deoxythymidine (dT) in succession, and in 6 of these species the BrdU/dT-banded chromosomes could be arranged into karyotypes. In the 3 species of the clade with 2n = 20 and 4n = 40 chromosomes (X. tropicalis, X. epitropicalis, X. new tetraploid 1), as well as in the 3 species with 4n = 36 chromosomes (X. laevis, X. borealis, X. muelleri), the BrdU/dT-banded karyotypes show a high degree of homoeology, though differences were detected between these groups. Translocations, inversions, insertions or sex-specific replication bands were not observed. Minor replication asynchronies found between chromosomes probably involve heterochromatic regions. BrdU/dT replication banding of Xenopus chromosomes provides the landmarks necessary for the exact physical mapping of genes and repetitive sequences. FISH with an X. laevis 5S rDNA probe detected multiple hybridization sites at or near the long-arm telomeric regions in most chromosomes of X. laevis and X. borealis, whereas in X. muelleri, the 5S rDNA sequences are located exclusively at the long-arm telomeres of a single chromosome pair. Staining with the AT base pair-specific fluorochrome quinacrine mustard revealed brightly fluorescing heterochromatic regions in the majority of X. borealis chromosomes which are absent in other Xenopus species.
SPAK and OSR1 Sensitivity of Excitatory Amino Acid Transporter EAAT3
Authors: Borrás José , Salker Madhuri S. , Elvira Bernat , Warsi Jamshed , Fezai Myriam , Hoseinzadeh Zohreh , Lang Florian
Published: June 2015

Background/Aims: Kinases involved in the regulation of epithelial transport include SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1). SPAK and OSR1 are both regulated by WNK (with-no-K(Lys)) kinases. The present study explored whether SPAK and/or OSR1 influence the excitatory amino acid transporter EAAT3, which accomplishes glutamate and aspartate transport in kidney, intestine and brain. Methods: cRNA encoding EAAT3 was injected into Xenopus laevis oocytes with or without additional injection of cRNA encoding wild-type SPAK, constitutively active T233ESPAK, WNK insensitive T233ASPAK, catalytically inactive D212ASPAK, wild-type OSR1, constitutively active T185EOSR1, WNK insensitive T185AOSR1 and catalytically inactive D164AOSR1. Glutamate-induced current was taken as measure of electrogenic glutamate transport and was quantified utilizing dual electrode voltage clamp. Furthermore, Ussing chamber was employed to determine glutamate transport in the intestine from gene-targeted mice carrying WNK insensitive SPAK (spaktg/tg) and from corresponding wild-type mice (spak+/+). Results: EAAT3 activity was significantly decreased by wild-type SPAK and T233ESPAK, but not by T233ASPAK and D212ASPAK. SPAK decreased maximal transport rate without affecting significantly affinity of the carrier. Similarly, EAAT3 activity was significantly downregulated by wild-type OSR1 and T185EOSR1, but not by T185AOSR1 and D164AOSR1. Again OSR1 decreased maximal transport rate without affecting significantly affinity of the carrier. Intestinal electrogenic glutamate transport was significantly lower in spak+/+ than in spaktg/tg mice. Conclusion: Both, SPAK and OSR1 are negative regulators of EAAT3 activity.
Drug-Immune Thrombocytopenia with Thrombosis versus Heparin-Induced Thrombocytopenia: A Critical Clinical Controversy
Authors: Al-Jafar Hassan , Al-Yousef Anas , Al-Shatti Somaya , Al-Banwan Khalifa
Published: June 2015

Heparin-induced thrombocytopenia (HIT) is a type of drug-induced immune thrombocytopenia (DITP). DITP is a rare and challenging clinical issue, especially when it is associated with thrombosis. A 62-year-old woman was admitted to our institution with end-stage renal failure. She received heparin for hemodialysis. Six days later, she became febrile and was treated with vancomycin and amikacin antibiotics. Two days after starting the vancomycin, she developed severe thrombocytopenia with extensive gangrenous deep vein thrombosis in her right leg, which required a below-the-knee amputation. The HIT test yielded positive results when heparin was already stopped, but her platelet count did not regenerate even after 3 months of heparin-free treatment. Courses of vancomycin treatment were given during several febrile episodes over the long period of severe thrombocytopenia. The patient was given both anti-immune thrombocytopenia and anticoagulant treatments because of both severe persistent thrombocytopenia and recurrent thrombotic episodes. The patient died as a result of severe thrombocytopenia, recurrent infection, and blood loss from the amputation site. Vancomycin is known to cause DITP, thrombosis, and immune complexes. DITP is a bleeding disorder, whereas HIT is a controversial thrombotic disorder. HIT tests can be influenced by cross-reacting antibodies and many other factors. Thus, there is no single method that can be considered 100% effective in confirming the HIT diagnosis. Anticoagulants must be used with great caution in patients with suspected DITP. Treatment of HIT-positive cases requires both clinical correlation and experience rather than reliance on HIT tests alone.
Validation of an Organizational Management Model of Remote Implantable Cardioverter-Defibrillator Monitoring Alerts
Authors: Guédon-Moreau Laurence , Finat Loïc , Boulé Stéphane , Wissocque Ludivine , Marquié Christelle , Brigadeau François , Kouakam Claude , Mondésert Blandine , Kacet Salem , Klug Didier , Lacroix Dominique
Published: June 2015

Background—

Implantable cardioverter-defibrillators (ICDs) are a standard means of sudden cardiac death prevention. Compared with ambulatory visits, remote monitoring (RM) of ICD recipients has improved the quality of health care and spared its resources. Few studies have addressed the organization of RM. We optimized and validated our institutional model of RM organization for ICD recipients.

Methods and Results—

This observational study of 562 ICD recipients compared 2 RM periods consisting of iterative, qualitative, and quantitative (1) device diagnostic evaluations by nurses and cardiologists; and (2) selected decisional trees. The main study end points were the professional interventions prompted by, and times allocated to, RM alerts. During the first period, 1134 alerts occurred in 427 patients (286 patient-year), of which 376 (33%) were submitted to cardiologists’ reviews, compared with, 1522 alerts in 562 patients (458 patient-year), of which 273 (18%) were submitted to cardiologists’ reviews during the second period (
P
<0.001). An intervention was prompted by 73 of 376 (19.4%) alerts in the first versus 77 of 273 (28.2%) in the second period (
P
=0.009). The mean time to manage an alert was 4 minutes 31 s in the first versus 2 minutes 10 s in the second period (
P
<0.001). The annual numbers of alert-related hospitalizations were 10.8 versus 8.1 per 100-patient-year (
P
=0.230), and annual numbers of alert-related visits were 9.8 and 6.1 per 100-patient-year (
P
=0.081), respectively.

Conclusions—

An optimized RM organization based on automated alerts and decisional trees enabled a focus on clinically relevant events and a decrease in the consumption of resources without compromising the quality of ICD recipients’ care.