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Sample records for based differential equationalgoritmo

  1. Reconcilable Differences: Standards-based Teaching and Differentiation.

    Science.gov (United States)

    Tomlinson, Carol Ann

    2000-01-01

    There is no contradiction between effective standards-based instruction and differentiation. Curriculum tells teachers what to teach; differentiation tells how. Teachers can challenge all learners by providing standards-based materials and tasks calling for varied difficulty levels, scaffolding, instructional styles, and learning times. (MLH)

  2. Solar-Based Boost Differential Single Phase Inverter | Eya | Nigerian ...

    African Journals Online (AJOL)

    Solar-Based Boost Differential Single Phase Inverter. ... Solar-based boost differential inverter is reduced down to 22.37% in closed loop system with the aid of Proportional –integral-Differential (PID) ... The dc power source is photovoltaic cell.

  3. Optical spatial differentiator based on subwavelength high-contrast gratings

    Science.gov (United States)

    Dong, Zhewei; Si, Jiangnan; Yu, Xuanyi; Deng, Xiaoxu

    2018-04-01

    An optical spatial differentiator based on subwavelength high-contrast gratings (HCGs) is proposed experimentally. The spatial differentiation property of the subwavelength HCG is analyzed by calculating its spatial spectral transfer function based on the periodic waveguide theory. By employing the FDTD solutions, the performance of the subwavelength HCG spatial differentiator was investigated numerically. The subwavelength HCG differentiator with the thickness at the nanoscale was fabricated on the quartz substrate by electron beam lithography and Bosch deep silicon etching. Observed under an optical microscope with a CCD camera, the spatial differentiation of the incident field profile was obtained by the subwavelength HCG differentiator in transmission without Fourier lens. By projecting the images of slits, letter "X," and a cross on the subwavelength HCG differentiator, edge detections of images were obtained in transmission. With the nanoscale HCG structure and simple optical implementation, the proposed optical spatial differentiator provides the prospects for applications in optical computing systems and parallel data processing.

  4. Ultrasound speckle reduction based on fractional order differentiation.

    Science.gov (United States)

    Shao, Dangguo; Zhou, Ting; Liu, Fan; Yi, Sanli; Xiang, Yan; Ma, Lei; Xiong, Xin; He, Jianfeng

    2017-07-01

    Ultrasound images show a granular pattern of noise known as speckle that diminishes their quality and results in difficulties in diagnosis. To preserve edges and features, this paper proposes a fractional differentiation-based image operator to reduce speckle in ultrasound. An image de-noising model based on fractional partial differential equations with balance relation between k (gradient modulus threshold that controls the conduction) and v (the order of fractional differentiation) was constructed by the effective combination of fractional calculus theory and a partial differential equation, and the numerical algorithm of it was achieved using a fractional differential mask operator. The proposed algorithm has better speckle reduction and structure preservation than the three existing methods [P-M model, the speckle reducing anisotropic diffusion (SRAD) technique, and the detail preserving anisotropic diffusion (DPAD) technique]. And it is significantly faster than bilateral filtering (BF) in producing virtually the same experimental results. Ultrasound phantom testing and in vivo imaging show that the proposed method can improve the quality of an ultrasound image in terms of tissue SNR, CNR, and FOM values.

  5. Differentiated protection services with failure probability guarantee for workflow-based applications

    Science.gov (United States)

    Zhong, Yaoquan; Guo, Wei; Jin, Yaohui; Sun, Weiqiang; Hu, Weisheng

    2010-12-01

    A cost-effective and service-differentiated provisioning strategy is very desirable to service providers so that they can offer users satisfactory services, while optimizing network resource allocation. Providing differentiated protection services to connections for surviving link failure has been extensively studied in recent years. However, the differentiated protection services for workflow-based applications, which consist of many interdependent tasks, have scarcely been studied. This paper investigates the problem of providing differentiated services for workflow-based applications in optical grid. In this paper, we develop three differentiated protection services provisioning strategies which can provide security level guarantee and network-resource optimization for workflow-based applications. The simulation demonstrates that these heuristic algorithms provide protection cost-effectively while satisfying the applications' failure probability requirements.

  6. Differentiated instruction in a data-based decision-making context

    NARCIS (Netherlands)

    Faber, Janke M.; Glas, Cees A.W.; Visscher, Adrie J.

    2018-01-01

    In this study, the relationship between differentiated instruction, as an element of data-based decision making, and student achievement was examined. Classroom observations (n = 144) were used to measure teachers’ differentiated instruction practices and to predict the mathematical achievement of

  7. Modulation of DNA base excision repair during neuronal differentiation

    DEFF Research Database (Denmark)

    Sykora, Peter; Yang, Jenq-Lin; Ferrarelli, Leslie K

    2013-01-01

    DNA damage susceptibility and base excision DNA repair (BER) capacity in undifferentiated and differentiated human neural cells. The results show that undifferentiated human SH-SY5Y neuroblastoma cells are less sensitive to oxidative damage than their differentiated counterparts, in part because...

  8. Differential geometry based multiscale models.

    Science.gov (United States)

    Wei, Guo-Wei

    2010-08-01

    Large chemical and biological systems such as fuel cells, ion channels, molecular motors, and viruses are of great importance to the scientific community and public health. Typically, these complex systems in conjunction with their aquatic environment pose a fabulous challenge to theoretical description, simulation, and prediction. In this work, we propose a differential geometry based multiscale paradigm to model complex macromolecular systems, and to put macroscopic and microscopic descriptions on an equal footing. In our approach, the differential geometry theory of surfaces and geometric measure theory are employed as a natural means to couple the macroscopic continuum mechanical description of the aquatic environment with the microscopic discrete atomistic description of the macromolecule. Multiscale free energy functionals, or multiscale action functionals are constructed as a unified framework to derive the governing equations for the dynamics of different scales and different descriptions. Two types of aqueous macromolecular complexes, ones that are near equilibrium and others that are far from equilibrium, are considered in our formulations. We show that generalized Navier-Stokes equations for the fluid dynamics, generalized Poisson equations or generalized Poisson-Boltzmann equations for electrostatic interactions, and Newton's equation for the molecular dynamics can be derived by the least action principle. These equations are coupled through the continuum-discrete interface whose dynamics is governed by potential driven geometric flows. Comparison is given to classical descriptions of the fluid and electrostatic interactions without geometric flow based micro-macro interfaces. The detailed balance of forces is emphasized in the present work. We further extend the proposed multiscale paradigm to micro-macro analysis of electrohydrodynamics, electrophoresis, fuel cells, and ion channels. We derive generalized Poisson-Nernst-Planck equations that are

  9. Differential Geometry Based Multiscale Models

    Science.gov (United States)

    Wei, Guo-Wei

    2010-01-01

    Large chemical and biological systems such as fuel cells, ion channels, molecular motors, and viruses are of great importance to the scientific community and public health. Typically, these complex systems in conjunction with their aquatic environment pose a fabulous challenge to theoretical description, simulation, and prediction. In this work, we propose a differential geometry based multiscale paradigm to model complex macromolecular systems, and to put macroscopic and microscopic descriptions on an equal footing. In our approach, the differential geometry theory of surfaces and geometric measure theory are employed as a natural means to couple the macroscopic continuum mechanical description of the aquatic environment with the microscopic discrete atom-istic description of the macromolecule. Multiscale free energy functionals, or multiscale action functionals are constructed as a unified framework to derive the governing equations for the dynamics of different scales and different descriptions. Two types of aqueous macromolecular complexes, ones that are near equilibrium and others that are far from equilibrium, are considered in our formulations. We show that generalized Navier–Stokes equations for the fluid dynamics, generalized Poisson equations or generalized Poisson–Boltzmann equations for electrostatic interactions, and Newton's equation for the molecular dynamics can be derived by the least action principle. These equations are coupled through the continuum-discrete interface whose dynamics is governed by potential driven geometric flows. Comparison is given to classical descriptions of the fluid and electrostatic interactions without geometric flow based micro-macro interfaces. The detailed balance of forces is emphasized in the present work. We further extend the proposed multiscale paradigm to micro-macro analysis of electrohydrodynamics, electrophoresis, fuel cells, and ion channels. We derive generalized Poisson–Nernst–Planck equations that

  10. Density based pruning for identification of differentially expressed genes from microarray data

    Directory of Open Access Journals (Sweden)

    Xu Jia

    2010-11-01

    Full Text Available Abstract Motivation Identification of differentially expressed genes from microarray datasets is one of the most important analyses for microarray data mining. Popular algorithms such as statistical t-test rank genes based on a single statistics. The false positive rate of these methods can be improved by considering other features of differentially expressed genes. Results We proposed a pattern recognition strategy for identifying differentially expressed genes. Genes are mapped to a two dimension feature space composed of average difference of gene expression and average expression levels. A density based pruning algorithm (DB Pruning is developed to screen out potential differentially expressed genes usually located in the sparse boundary region. Biases of popular algorithms for identifying differentially expressed genes are visually characterized. Experiments on 17 datasets from Gene Omnibus Database (GEO with experimentally verified differentially expressed genes showed that DB pruning can significantly improve the prediction accuracy of popular identification algorithms such as t-test, rank product, and fold change. Conclusions Density based pruning of non-differentially expressed genes is an effective method for enhancing statistical testing based algorithms for identifying differentially expressed genes. It improves t-test, rank product, and fold change by 11% to 50% in the numbers of identified true differentially expressed genes. The source code of DB pruning is freely available on our website http://mleg.cse.sc.edu/degprune

  11. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed; Zidan, Mohammed A.; Salama, Khaled N.

    2012-01-01

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  12. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed

    2012-09-06

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  13. Constructing regional advantage: platform policies based on related variety and differentiated knowledge bases.

    NARCIS (Netherlands)

    Asheim, B.T.; Boschma, R.A.; Cooke, P.

    2011-01-01

    Constructing regional advantage: platform policies based on related variety and differentiated knowledge bases, Regional Studies. This paper presents a regional innovation policy model based on the idea of constructing regional advantage. This policy model brings together concepts like related

  14. Digital differential confocal microscopy based on spatial shift transformation.

    Science.gov (United States)

    Liu, J; Wang, Y; Liu, C; Wilson, T; Wang, H; Tan, J

    2014-11-01

    Differential confocal microscopy is a particularly powerful surface profilometry technique in industrial metrology due to its high axial sensitivity and insensitivity to noise. However, the practical implementation of the technique requires the accurate positioning of point detectors in three-dimensions. We describe a simple alternative based on spatial transformation of a through-focus series of images obtained from a homemade beam scanning confocal microscope. This digital differential confocal microscopy approach is described and compared with the traditional Differential confocal microscopy approach. The ease of use of the digital differential confocal microscopy system is illustrated by performing measurements on a 3D standard specimen. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  15. Design and Experiment of a Differential-Based Power Split Device

    Directory of Open Access Journals (Sweden)

    Xiaohua Zeng

    2014-04-01

    Full Text Available Hybrid electric vehicles have excellent energy efficiency and emission performance. Power split device (PSD is a key component that directly affects the control strategy of power systems, the economic consumption of fuel, and the dynamic performance of vehicles. A differential-based PSD was proposed in this paper. A traditional differential was taken as the prototype and a new design method is proposed to retrofit the differential into a PSD. First, a comprehensive approach that includes theoretical analysis and software simulation was used to analyze the possibility as well as the necessity of retrofitting the differential into PSD. Then the differential was retrofitted. Finally, finite element analysis and bench test were conducted. Results showed that applying the retrofitted differential as PSD is practicable.

  16. Link-based quantitative methods to identify differentially coexpressed genes and gene Pairs

    Directory of Open Access Journals (Sweden)

    Ye Zhi-Qiang

    2011-08-01

    Full Text Available Abstract Background Differential coexpression analysis (DCEA is increasingly used for investigating the global transcriptional mechanisms underlying phenotypic changes. Current DCEA methods mostly adopt a gene connectivity-based strategy to estimate differential coexpression, which is characterized by comparing the numbers of gene neighbors in different coexpression networks. Although it simplifies the calculation, this strategy mixes up the identities of different coexpression neighbors of a gene, and fails to differentiate significant differential coexpression changes from those trivial ones. Especially, the correlation-reversal is easily missed although it probably indicates remarkable biological significance. Results We developed two link-based quantitative methods, DCp and DCe, to identify differentially coexpressed genes and gene pairs (links. Bearing the uniqueness of exploiting the quantitative coexpression change of each gene pair in the coexpression networks, both methods proved to be superior to currently popular methods in simulation studies. Re-mining of a publicly available type 2 diabetes (T2D expression dataset from the perspective of differential coexpression analysis led to additional discoveries than those from differential expression analysis. Conclusions This work pointed out the critical weakness of current popular DCEA methods, and proposed two link-based DCEA algorithms that will make contribution to the development of DCEA and help extend it to a broader spectrum.

  17. Maglev Train Signal Processing Architecture Based on Nonlinear Discrete Tracking Differentiator.

    Science.gov (United States)

    Wang, Zhiqiang; Li, Xiaolong; Xie, Yunde; Long, Zhiqiang

    2018-05-24

    In a maglev train levitation system, signal processing plays an important role for the reason that some sensor signals are prone to be corrupted by noise due to the harsh installation and operation environment of sensors and some signals cannot be acquired directly via sensors. Based on these concerns, an architecture based on a new type of nonlinear second-order discrete tracking differentiator is proposed. The function of this signal processing architecture includes filtering signal noise and acquiring needed signals for levitation purposes. The proposed tracking differentiator possesses the advantages of quick convergence, no fluttering, and simple calculation. Tracking differentiator's frequency characteristics at different parameter values are studied in this paper. The performance of this new type of tracking differentiator is tested in a MATLAB simulation and this tracking-differentiator is implemented in Very-High-Speed Integrated Circuit Hardware Description Language (VHDL). In the end, experiments are conducted separately on a test board and a maglev train model. Simulation and experiment results show that the performance of this novel signal processing architecture can fulfill the real system requirement.

  18. Differential alkylation-based redox proteomics - Lessons learnt

    DEFF Research Database (Denmark)

    Wojdyla, Katarzyna; Rogowska-Wrzesinska, Adelina

    2015-01-01

    Cysteine is one of the most reactive amino acids. This is due to the electronegativity of sulphur atom in the side chain of thiolate group. It results in cysteine being present in several distinct redox forms inside the cell. Amongst these, reversible oxidations, S-nitrosylation and S-sulfenylati......Cysteine is one of the most reactive amino acids. This is due to the electronegativity of sulphur atom in the side chain of thiolate group. It results in cysteine being present in several distinct redox forms inside the cell. Amongst these, reversible oxidations, S-nitrosylation and S......-sulfenylation are crucial mediators of intracellular redox signalling, with known associations to health and disease. Study of their functionalities has intensified thanks to the development of various analytical strategies, with particular contribution from differential alkylation-based proteomics methods. Presented here...... is a critical evaluation of differential alkylation-based strategies for the analysis of S-nitrosylation and S-sulfenylation. The aim is to assess the current status and to provide insights for future directions in the dynamically evolving field of redox proteomics. To achieve that we collected 35 original...

  19. Random number generation based on digital differential chaos

    KAUST Repository

    Zidan, Mohammed A.; Radwan, Ahmed G.; Salama, Khaled N.

    2012-01-01

    In this paper, we present a fully digital differential chaos based random number generator. The output of the digital circuit is proved to be chaotic by calculating the output time series maximum Lyapunov exponent. We introduce a new post processing

  20. Proteinuria: The diagnostic strategy based on urine proteins differentiation

    Directory of Open Access Journals (Sweden)

    Stojimirović Biljana B.

    2004-01-01

    Full Text Available Basal glomerular membrane represents mechanical and electrical barrier for passing of the plasma proteins. Mechanical barrier is composed of cylindrical pores and filtration fissure, and negative layer charge in exterior and interior side of basal glomerular membrane, made of heparan sulphate and sialoglicoproteine, provides certain electrical barrier. Diagnostic strategy based on different serum and urine proteins enables the differentiation of various types of proteinuria. Depending on etiology of proteinuria it can be prerenal, renal and postrenal. By analyzing albumin, armicroglobulin, immunoglobulin G and armacroglobulin, together with total protein in urine, it is possible to detect and differentiate causes of prerenal, renal (glomerular, tubular, glomerulo-tubular and postrenal proteinuria. The adequate and early differentiation of proteinuria type is of an immense diagnostic and therapeutic importance.

  1. Proliferation and osteoblastic differentiation of hMSCs on cellulose-based hydrogels.

    Science.gov (United States)

    Raucci, Maria Grazia; Alvarez-Perez, Marco Antonio; Demitri, Christian; Sannino, Alessandro; Ambrosio, Luigi

    2012-01-01

    The aim of this project was to study the proliferation and differentiation of human Mesenchymal Stem Cells (hMSCs) onto a cellulose-based hydrogel for bone tissue engineering. Modified-cellulose hydrogel was prepared via double esterification crosslinking using citric acid. The response of human Mesenchymal Stem Cells (hMSCs) in terms of cell proliferation and differentiation into osteoblastic phenotype was evaluated by using Alamar blue assay and Alkaline phosphatase activity. The results showed that CMCNa and CMCNa_CA have no negative effect on hMSC, adhesion and proliferation. Moreover, the increase of the ALP expression for CMCNa_CA confirms the ability of the hydrogels to support the osteoblastic differentiation. The cellulose-based hydrogels have a potential application as filler in bone tissue regeneration.

  2. Stochastic Differential Equation-Based Flexible Software Reliability Growth Model

    Directory of Open Access Journals (Sweden)

    P. K. Kapur

    2009-01-01

    Full Text Available Several software reliability growth models (SRGMs have been developed by software developers in tracking and measuring the growth of reliability. As the size of software system is large and the number of faults detected during the testing phase becomes large, so the change of the number of faults that are detected and removed through each debugging becomes sufficiently small compared with the initial fault content at the beginning of the testing phase. In such a situation, we can model the software fault detection process as a stochastic process with continuous state space. In this paper, we propose a new software reliability growth model based on Itô type of stochastic differential equation. We consider an SDE-based generalized Erlang model with logistic error detection function. The model is estimated and validated on real-life data sets cited in literature to show its flexibility. The proposed model integrated with the concept of stochastic differential equation performs comparatively better than the existing NHPP-based models.

  3. Collage-based approaches for elliptic partial differential equations inverse problems

    Science.gov (United States)

    Yodzis, Michael; Kunze, Herb

    2017-01-01

    The collage method for inverse problems has become well-established in the literature in recent years. Initial work developed a collage theorem, based upon Banach's fixed point theorem, for treating inverse problems for ordinary differential equations (ODEs). Amongst the subsequent work was a generalized collage theorem, based upon the Lax-Milgram representation theorem, useful for treating inverse problems for elliptic partial differential equations (PDEs). Each of these two different approaches can be applied to elliptic PDEs in one space dimension. In this paper, we explore and compare how the two different approaches perform for the estimation of the diffusivity for a steady-state heat equation.

  4. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Pay differentials claimed to be based on extra duties. 1620.20 Section 1620.20 Labor Regulations Relating to Labor (Continued) EQUAL EMPLOYMENT OPPORTUNITY COMMISSION THE EQUAL PAY ACT § 1620.20 Pay differentials claimed to be based on extra duties. Additional...

  5. Solving SAT Problem Based on Hybrid Differential Evolution Algorithm

    Science.gov (United States)

    Liu, Kunqi; Zhang, Jingmin; Liu, Gang; Kang, Lishan

    Satisfiability (SAT) problem is an NP-complete problem. Based on the analysis about it, SAT problem is translated equally into an optimization problem on the minimum of objective function. A hybrid differential evolution algorithm is proposed to solve the Satisfiability problem. It makes full use of strong local search capacity of hill-climbing algorithm and strong global search capability of differential evolution algorithm, which makes up their disadvantages, improves the efficiency of algorithm and avoids the stagnation phenomenon. The experiment results show that the hybrid algorithm is efficient in solving SAT problem.

  6. Clinical Study on the Visceral Differentiation-Based Acupuncture Therapy for Insomnia

    Institute of Scientific and Technical Information of China (English)

    LING Li; JIANG Xin-mei; XUE Jin-wei; WANG Miao; KE Rui

    2008-01-01

    objective;To investigate the clinical effects of acupuncture for insomnia on the basis of visceral differentiation.Methods;Seventy cases of insomnia were randomly divided into a treatment group and a control group,The former was treated by acupuncture based on visceral differentiation and the latter by the routine acupuncture therapy.Results;The clinical effcts were significantly better in the treatment group than that of the control group(P<0.05).Conclusion;The visceral difrerentiation-based acupuncture therapy may enhance the therapeutic effects for insomnia patients.

  7. Maglev Train Signal Processing Architecture Based on Nonlinear Discrete Tracking Differentiator

    Directory of Open Access Journals (Sweden)

    Zhiqiang Wang

    2018-05-01

    Full Text Available In a maglev train levitation system, signal processing plays an important role for the reason that some sensor signals are prone to be corrupted by noise due to the harsh installation and operation environment of sensors and some signals cannot be acquired directly via sensors. Based on these concerns, an architecture based on a new type of nonlinear second-order discrete tracking differentiator is proposed. The function of this signal processing architecture includes filtering signal noise and acquiring needed signals for levitation purposes. The proposed tracking differentiator possesses the advantages of quick convergence, no fluttering, and simple calculation. Tracking differentiator’s frequency characteristics at different parameter values are studied in this paper. The performance of this new type of tracking differentiator is tested in a MATLAB simulation and this tracking-differentiator is implemented in Very-High-Speed Integrated Circuit Hardware Description Language (VHDL. In the end, experiments are conducted separately on a test board and a maglev train model. Simulation and experiment results show that the performance of this novel signal processing architecture can fulfill the real system requirement.

  8. Differential evolution based method for total transfer capability ...

    African Journals Online (AJOL)

    The application of Differential Evolution (DE) to compute the Total Transfer Capability (TTC) in deregulated market is proposed in this paper. The objective is to maximize a specific point-to-point power transaction without violating system constraints using DE. This algorithm is based on full ac optimal power flow solution to ...

  9. and O-based composite materials derived from differential ...

    Indian Academy of Sciences (India)

    Abstract. In this work, we have made an effort to determine whether the effective atomic numbers of H-, C-, N- and O-based composite materials would indeed remain a constant over the energy grid of 280–1200 keV wherein incoherent scattering dominates their interaction with photons. For this purpose, the differential ...

  10. Novel Design of Recursive Differentiator Based on Lattice Wave Digital Filter

    Directory of Open Access Journals (Sweden)

    R. Barsainya

    2017-04-01

    Full Text Available In this paper, a novel design of third and fifth order differentiator based on lattice wave digital filter (LWDF, established on optimizing L_1-error approximation function using cuckoo search algorithm (CSA is proposed. We present a novel realization of minimum multiplier differentiator using LWD structure leading to requirement of optimizing only N coefficients for Nth order differentiator. The gamma coefficients of lattice wave digital differentiator (LWDD are computed by minimizing the L_1-norm fitness function leading to a flat response. The superiority of the proposed LWDD is evident by comparing it with other differentiators mentioned in the literature. The magnitude response of the designed LWDD is found to be of high accuracy with flat response in a wide frequency range. The simulation and statistical results validates that the designed minimum multiplier LWDD circumvents the existing one in terms of minimum absolute magnitude error, mean relative error (dB and efficient structural realization, thereby making the proposed LWDD a promising approach to digital differentiator design.

  11. Saturation Detection-Based Blocking Scheme for Transformer Differential Protection

    Directory of Open Access Journals (Sweden)

    Byung Eun Lee

    2014-07-01

    Full Text Available This paper describes a current differential relay for transformer protection that operates in conjunction with a core saturation detection-based blocking algorithm. The differential current for the magnetic inrush or over-excitation has a point of inflection at the start and end of each saturation period of the transformer core. At these instants, discontinuities arise in the first-difference function of the differential current. The second- and third-difference functions convert the points of inflection into pulses, the magnitudes of which are large enough to detect core saturation. The blocking signal is activated if the third-difference of the differential current is larger than the threshold and is maintained for one cycle. In addition, a method to discriminate between transformer saturation and current transformer (CT saturation is included. The performance of the proposed blocking scheme was compared with that of a conventional harmonic blocking method. The test results indicate that the proposed scheme successfully discriminates internal faults even with CT saturation from the magnetic inrush, over-excitation, and external faults with CT saturation, and can significantly reduce the operating time delay of the relay.

  12. Differentiating case-based learning from problem-based learning after a twoday introductory workshop on case-based learning

    Directory of Open Access Journals (Sweden)

    Aqil Mohammad Daher

    2017-12-01

    Full Text Available Background Considerable overlap exists between case-based learning (CBL and problem-based learning (PBL and differentiating between the two can be difficult for a lot of the academicians. Aims This study gauged the ability of members of medical school, familiar with a problem-based learning (PBL curriculum, to differentiate between case-based learning (CBL and PBL after a two-day workshop on CBL. Methods A questionnaire was distributed to all participants, attending the introductory course on CBL. It was designed to document the basic characteristics of the respondents, their preference for either CBL or PBL, their ability to recognize differences between CBL and PBL, and their overall perception of the course. Results Of the total workshop participants, 80.5 per cent returned the completed questionnaire. The mean age of the respondents was 44.12±12.31 years and women made up a slight majority. Majority favoured CBL over PBL and felt it was more clinical, emphasizes on self-directed learning, provides more opportunities for learning, permits in-depth exploration of cases, has structured environment and encourages the use of all learning resources. On the respondents’ ability to discriminate CBL from PBL, a weighted score of 39.9 per cent indicated a failure on the part of the respondents to correctly identify differences between CBL and PBL. Less than half opined that CBL was a worthwhile progression from PBL and about third would recommend CBL over PBL. Conclusion It seems that majority of the respondents failed to adequately differentiate between CBL and PBL and didn’t favour CBL over PBL.

  13. Testing Differential Effects of Computer-Based, Web-Based and Paper-Based Administration of Questionnaire Research Instruments

    Science.gov (United States)

    Hardre, Patricia L.; Crowson, H. Michael; Xie, Kui; Ly, Cong

    2007-01-01

    Translation of questionnaire instruments to digital administration systems, both self-contained and web-based, is widespread and increasing daily. However, the literature is lean on controlled empirical studies investigating the potential for differential effects of administrative methods. In this study, two university student samples were…

  14. Self-mixing differential vibrometer based on electronic channel subtraction

    International Nuclear Information System (INIS)

    Donati, Silvano; Norgia, Michele; Giuliani, Guido

    2006-01-01

    An instrument for noncontact measurement of differential vibrations is developed, based on the self-mixing interferometer. As no reference arm is available in the self-mixing configuration, the differential mode is obtained by electronic subtraction of signals from two (nominally equal) vibrometer channels, taking advantage that channels are servo stabilized and thus insensitive to speckle and other sources of amplitude fluctuation. We show that electronic subtraction is nearly as effective as field superposition. Common-mode suppression is 25-30 dB, the dynamic range (amplitude) is in excess of 100 μm, and the minimum measurable (differential) amplitude is 20 nm on aB=10 kHz bandwidth. The instrument has been used to measure vibrations of two metal samples kept in contact, revealing the hysteresis cycle in the microslip and gross-slip regimes, which are of interest in the study of friction induced vibration damping of gas turbine blades for aircraft applications

  15. Fault Detection Based on Tracking Differentiator Applied on the Suspension System of Maglev Train

    Directory of Open Access Journals (Sweden)

    Hehong Zhang

    2015-01-01

    Full Text Available A fault detection method based on the optimized tracking differentiator is introduced. It is applied on the acceleration sensor of the suspension system of maglev train. It detects the fault of the acceleration sensor by comparing the acceleration integral signal with the speed signal obtained by the optimized tracking differentiator. This paper optimizes the control variable when the states locate within or beyond the two-step reachable region to improve the performance of the approximate linear discrete tracking differentiator. Fault-tolerant control has been conducted by feedback based on the speed signal acquired from the optimized tracking differentiator when the acceleration sensor fails. The simulation and experiment results show the practical usefulness of the presented method.

  16. Differential alkylation-based redox proteomics--Lessons learnt.

    Science.gov (United States)

    Wojdyla, Katarzyna; Rogowska-Wrzesinska, Adelina

    2015-12-01

    Cysteine is one of the most reactive amino acids. This is due to the electronegativity of sulphur atom in the side chain of thiolate group. It results in cysteine being present in several distinct redox forms inside the cell. Amongst these, reversible oxidations, S-nitrosylation and S-sulfenylation are crucial mediators of intracellular redox signalling, with known associations to health and disease. Study of their functionalities has intensified thanks to the development of various analytical strategies, with particular contribution from differential alkylation-based proteomics methods. Presented here is a critical evaluation of differential alkylation-based strategies for the analysis of S-nitrosylation and S-sulfenylation. The aim is to assess the current status and to provide insights for future directions in the dynamically evolving field of redox proteomics. To achieve that we collected 35 original research articles published since 2010 and analysed them considering the following parameters, (i) resolution of modification site, (ii) quantitative information, including correction of modification levels by protein abundance changes and determination of modification site occupancy, (iii) throughput, including the amount of starting material required for analysis. The results of this meta-analysis are the core of this review, complemented by issues related to biological models and sample preparation in redox proteomics, including conditions for free thiol blocking and labelling of target cysteine oxoforms. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Market-based transmission expansion planning by improved differential evolution

    International Nuclear Information System (INIS)

    Georgilakis, Pavlos S.

    2010-01-01

    The restructuring and deregulation has exposed the transmission planner to new objectives and uncertainties. As a result, new criteria and approaches are needed for transmission expansion planning (TEP) in deregulated electricity markets. This paper proposes a new market-based approach for TEP. An improved differential evolution (IDE) model is proposed for the solution of this new market-based TEP problem. The modifications of IDE in comparison to the simple differential evolution method are: (1) the scaling factor F is varied randomly within some range, (2) an auxiliary set is employed to enhance the diversity of the population, (3) the newly generated trial vector is compared with the nearest parent, and (4) the simple feasibility rule is used to treat the constraints. Results from the application of the proposed method on the IEEE 30-bus test system demonstrate the feasibility and practicality of the proposed IDE for the solution of TEP problem. (author)

  18. Spline based iterative phase retrieval algorithm for X-ray differential phase contrast radiography.

    Science.gov (United States)

    Nilchian, Masih; Wang, Zhentian; Thuering, Thomas; Unser, Michael; Stampanoni, Marco

    2015-04-20

    Differential phase contrast imaging using grating interferometer is a promising alternative to conventional X-ray radiographic methods. It provides the absorption, differential phase and scattering information of the underlying sample simultaneously. Phase retrieval from the differential phase signal is an essential problem for quantitative analysis in medical imaging. In this paper, we formalize the phase retrieval as a regularized inverse problem, and propose a novel discretization scheme for the derivative operator based on B-spline calculus. The inverse problem is then solved by a constrained regularized weighted-norm algorithm (CRWN) which adopts the properties of B-spline and ensures a fast implementation. The method is evaluated with a tomographic dataset and differential phase contrast mammography data. We demonstrate that the proposed method is able to produce phase image with enhanced and higher soft tissue contrast compared to conventional absorption-based approach, which can potentially provide useful information to mammographic investigations.

  19. PCL-PDMS-PCL copolymer-based microspheres mediate cardiovascular differentiation from embryonic stem cells

    Science.gov (United States)

    Song, Liqing

    Poly-epsilon-caprolactone (PCL) based copolymers have received much attention as drug or growth factor delivery carriers and tissue engineering scaffolds due to their biocompatibility, biodegradability, and tunable biophysical properties. Copolymers of PCL and polydimethylsiloxane (PDMS) also have shape memory behaviors and can be made into thermoresponsive shape memory polymers for various biomedical applications such as smart sutures and vascular stents. However, the influence of biophysical properties of PCL-PDMS-PCL copolymers on stem cell lineage commitment is not well understood. In this study, PDMS was used as soft segments of varying length to tailor the biophysical properties of PCL-based co-polymers. While low elastic modulus (affected cardiovascular differentiation of embryonic stem cells, the range of 60-100 MPa PCL-PDMS-PCL showed little influence on the differentiation. Then different size (30-140 mum) of microspheres were fabricated from PCL-PDMS-PCL copolymers and incorporated within embryoid bodies (EBs). Mesoderm differentiation was induced using bone morphogenetic protein (BMP)-4 for cardiovascular differentiation. Differential expressions of mesoderm progenitor marker KDR and vascular markers CD31 and VE-cadherin were observed for the cells differentiated from EBs incorporated with microspheres of different size, while little difference was observed for cardiac marker alpha-actinin expression. Small size of microspheres (30 mum) resulted in higher expression of KDR while medium size of microspheres (94 mum) resulted in higher CD31 and VE-cadherin expression. This study indicated that the biophysical properties of PCL-based copolymers impacted stem cell lineage commitment, which should be considered for drug delivery and tissue engineering applications.

  20. Experimental Validation of a Differential Variational Inequality-Based Approach for Handling Friction and Contact in Vehicle

    Science.gov (United States)

    2015-11-20

    terrain modeled using the discrete element method (DEM). Experimental Validation of a Differential Variational Inequality -Based Approach for Handling...COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Experimental Validation of a Differential Variational Inequality -Based Approach for...sinkage, and single wheel tests. 1.1. Modeling Frictional Contact Via Differential Variational Inequalities Consider a three dimensional (3D) system of

  1. Combined Differential and Static Pressure Sensor based on a Double-Bridged Structure

    DEFF Research Database (Denmark)

    Pedersen, Casper; Jespersen, S.T.; Krog, J.P.

    2005-01-01

    A combined differential and static silicon microelectromechanical system pressure sensor based on a double piezoresistive Wheatstone bridge structure is presented. The developed sensor has a conventional (inner) bridge on a micromachined diaphragm and a secondary (outer) bridge on the chip...... substrate. A novel approach is demonstrated with a combined measurement of outputs from the two bridges, which results in a combined deduction of both differential and static media pressure. Also following this new approach, a significant improvement in differential pressure sensor accuracy is achieved....... Output from the two bridges depends linearly on both differential and absolute (relative to atmospheric pressure) media pressure. Furthermore, the sensor stress distributions involved are studied by three-dimensional finite-element (FE) stress analysis. Furthermore, the FE analysis evaluates current...

  2. The Cellular Differential Evolution Based on Chaotic Local Search

    Directory of Open Access Journals (Sweden)

    Qingfeng Ding

    2015-01-01

    Full Text Available To avoid immature convergence and tune the selection pressure in the differential evolution (DE algorithm, a new differential evolution algorithm based on cellular automata and chaotic local search (CLS or ccDE is proposed. To balance the exploration and exploitation tradeoff of differential evolution, the interaction among individuals is limited in cellular neighbors instead of controlling parameters in the canonical DE. To improve the optimizing performance of DE, the CLS helps by exploring a large region to avoid immature convergence in the early evolutionary stage and exploiting a small region to refine the final solutions in the later evolutionary stage. What is more, to improve the convergence characteristics and maintain the population diversity, the binomial crossover operator in the canonical DE may be instead by the orthogonal crossover operator without crossover rate. The performance of ccDE is widely evaluated on a set of 14 bound constrained numerical optimization problems compared with the canonical DE and several DE variants. The simulation results show that ccDE has better performances in terms of convergence rate and solution accuracy than other optimizers.

  3. Average Gait Differential Image Based Human Recognition

    Directory of Open Access Journals (Sweden)

    Jinyan Chen

    2014-01-01

    Full Text Available The difference between adjacent frames of human walking contains useful information for human gait identification. Based on the previous idea a silhouettes difference based human gait recognition method named as average gait differential image (AGDI is proposed in this paper. The AGDI is generated by the accumulation of the silhouettes difference between adjacent frames. The advantage of this method lies in that as a feature image it can preserve both the kinetic and static information of walking. Comparing to gait energy image (GEI, AGDI is more fit to representation the variation of silhouettes during walking. Two-dimensional principal component analysis (2DPCA is used to extract features from the AGDI. Experiments on CASIA dataset show that AGDI has better identification and verification performance than GEI. Comparing to PCA, 2DPCA is a more efficient and less memory storage consumption feature extraction method in gait based recognition.

  4. Personalized Medicine Based on Theranostic Radioiodine Molecular Imaging for Differentiated Thyroid Cancer.

    Science.gov (United States)

    Ahn, Byeong-Cheol

    2016-01-01

    Molecular imaging based personalized therapy has been a fascinating concept for individualized therapeutic strategy, which is able to attain the highest efficacy and reduce adverse effects in certain patients. Theranostics, which integrates diagnostic testing to detect molecular targets for particular therapeutic modalities, is one of the key technologies that contribute to the success of personalized medicine. Although the term "theranostics" was used after the second millennium, its basic principle was applied more than 70 years ago in the field of thyroidology with radioiodine molecular imaging. Differentiated thyroid cancer, which arises from follicular cells in the thyroid, is the most common endocrine malignancy, and theranostic radioiodine has been successfully applied to diagnose and treat differentiated thyroid cancer, the applications of which were included in the guidelines published by various thyroid or nuclear medicine societies. Through better pathophysiologic understanding of thyroid cancer and advancements in nuclear technologies, theranostic radioiodine contributes more to modern tailored personalized management by providing high therapeutic effect and by avoiding significant adverse effects in differentiated thyroid cancer. This review details the inception of theranostic radioiodine and recent radioiodine applications for differentiated thyroid cancer management as a prototype of personalized medicine based on molecular imaging.

  5. Fractal-Based Methods and Inverse Problems for Differential Equations: Current State of the Art

    Directory of Open Access Journals (Sweden)

    Herb E. Kunze

    2014-01-01

    Full Text Available We illustrate, in this short survey, the current state of the art of fractal-based techniques and their application to the solution of inverse problems for ordinary and partial differential equations. We review several methods based on the Collage Theorem and its extensions. We also discuss two innovative applications: the first one is related to a vibrating string model while the second one considers a collage-based approach for solving inverse problems for partial differential equations on a perforated domain.

  6. HYPERDIRE HYPERgeometric functions DIfferential REduction. Mathematica-based packages for the differential reduction of generalized hypergeometric functions. Lauricella function FC of three variables

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kniehl, Bernd A.

    2016-12-01

    We present a further extension of the HYPERDIRE project, which is devoted to the creation of a set of Mathematica-based program packages for manipulations with Horn-type hypergeometric functions on the basis of differential equations. Specifically, we present the implementation of the differential reduction for the Lauricella function F C of three variables.

  7. A Variable Order Fractional Differential-Based Texture Enhancement Algorithm with Application in Medical Imaging.

    Directory of Open Access Journals (Sweden)

    Qiang Yu

    Full Text Available Texture enhancement is one of the most important techniques in digital image processing and plays an essential role in medical imaging since textures discriminate information. Most image texture enhancement techniques use classical integral order differential mask operators or fractional differential mask operators using fixed fractional order. These masks can produce excessive enhancement of low spatial frequency content, insufficient enhancement of large spatial frequency content, and retention of high spatial frequency noise. To improve upon existing approaches of texture enhancement, we derive an improved Variable Order Fractional Centered Difference (VOFCD scheme which dynamically adjusts the fractional differential order instead of fixing it. The new VOFCD technique is based on the second order Riesz fractional differential operator using a Lagrange 3-point interpolation formula, for both grey scale and colour image enhancement. We then use this method to enhance photographs and a set of medical images related to patients with stroke and Parkinson's disease. The experiments show that our improved fractional differential mask has a higher signal to noise ratio value than the other fractional differential mask operators. Based on the corresponding quantitative analysis we conclude that the new method offers a superior texture enhancement over existing methods.

  8. Integration Processes of Delay Differential Equation Based on Modified Laguerre Functions

    Directory of Open Access Journals (Sweden)

    Yeguo Sun

    2012-01-01

    Full Text Available We propose long-time convergent numerical integration processes for delay differential equations. We first construct an integration process based on modified Laguerre functions. Then we establish its global convergence in certain weighted Sobolev space. The proposed numerical integration processes can also be used for systems of delay differential equations. We also developed a technique for refinement of modified Laguerre-Radau interpolations. Lastly, numerical results demonstrate the spectral accuracy of the proposed method and coincide well with analysis.

  9. Power Transformer Differential Protection Based on Neural Network Principal Component Analysis, Harmonic Restraint and Park's Plots

    OpenAIRE

    Tripathy, Manoj

    2012-01-01

    This paper describes a new approach for power transformer differential protection which is based on the wave-shape recognition technique. An algorithm based on neural network principal component analysis (NNPCA) with back-propagation learning is proposed for digital differential protection of power transformer. The principal component analysis is used to preprocess the data from power system in order to eliminate redundant information and enhance hidden pattern of differential current to disc...

  10. A Numerical Method for Partial Differential Algebraic Equations Based on Differential Transform Method

    Directory of Open Access Journals (Sweden)

    Murat Osmanoglu

    2013-01-01

    Full Text Available We have considered linear partial differential algebraic equations (LPDAEs of the form , which has at least one singular matrix of . We have first introduced a uniform differential time index and a differential space index. The initial conditions and boundary conditions of the given system cannot be prescribed for all components of the solution vector here. To overcome this, we introduced these indexes. Furthermore, differential transform method has been given to solve LPDAEs. We have applied this method to a test problem, and numerical solution of the problem has been compared with analytical solution.

  11. Solution of partial differential equations by agent-based simulation

    International Nuclear Information System (INIS)

    Szilagyi, Miklos N

    2014-01-01

    The purpose of this short note is to demonstrate that partial differential equations can be quickly solved by agent-based simulation with high accuracy. There is no need for the solution of large systems of algebraic equations. This method is especially useful for quick determination of potential distributions and demonstration purposes in teaching electromagnetism. (letters and comments)

  12. Differential Sarcomere and Electrophysiological Maturation of Human iPSC-Derived Cardiac Myocytes in Monolayer vs. Aggregation-Based Differentiation Protocols

    Directory of Open Access Journals (Sweden)

    Dorota Jeziorowska

    2017-06-01

    Full Text Available Human induced pluripotent stem cells (iPSCs represent a powerful human model to study cardiac disease in vitro, notably channelopathies and sarcomeric cardiomyopathies. Different protocols for cardiac differentiation of iPSCs have been proposed either based on embroid body formation (3D or, more recently, on monolayer culture (2D. We performed a direct comparison of the characteristics of the derived cardiomyocytes (iPSC-CMs on day 27 ± 2 of differentiation between 3D and 2D differentiation protocols with two different Wnt-inhibitors were compared: IWR1 (inhibitor of Wnt response or IWP2 (inhibitor of Wnt production. We firstly found that the level of Troponin T (TNNT2 expression measured by FACS was significantly higher for both 2D protocols as compared to the 3D protocol. In the three methods, iPSC-CM show sarcomeric structures. However, iPSC-CM generated in 2D protocols constantly displayed larger sarcomere lengths as compared to the 3D protocol. In addition, mRNA and protein analyses reveal higher cTNi to ssTNi ratios in the 2D protocol using IWP2 as compared to both other protocols, indicating a higher sarcomeric maturation. Differentiation of cardiac myocytes with 2D monolayer-based protocols and the use of IWP2 allows the production of higher yield of cardiac myocytes that have more suitable characteristics to study sarcomeric cardiomyopathies.

  13. Parameter identification of PEMFC model based on hybrid adaptive differential evolution algorithm

    International Nuclear Information System (INIS)

    Sun, Zhe; Wang, Ning; Bi, Yunrui; Srinivasan, Dipti

    2015-01-01

    In this paper, a HADE (hybrid adaptive differential evolution) algorithm is proposed for the identification problem of PEMFC (proton exchange membrane fuel cell). Inspired by biological genetic strategy, a novel adaptive scaling factor and a dynamic crossover probability are presented to improve the adaptive and dynamic performance of differential evolution algorithm. Moreover, two kinds of neighborhood search operations based on the bee colony foraging mechanism are introduced for enhancing local search efficiency. Through testing the benchmark functions, the proposed algorithm exhibits better performance in convergent accuracy and speed. Finally, the HADE algorithm is applied to identify the nonlinear parameters of PEMFC stack model. Through experimental comparison with other identified methods, the PEMFC model based on the HADE algorithm shows better performance. - Highlights: • We propose a hybrid adaptive differential evolution algorithm (HADE). • The search efficiency is enhanced in low and high dimension search space. • The effectiveness is confirmed by testing benchmark functions. • The identification of the PEMFC model is conducted by adopting HADE.

  14. Adaptive differential correspondence imaging based on sorting technique

    Directory of Open Access Journals (Sweden)

    Heng Wu

    2017-04-01

    Full Text Available We develop an adaptive differential correspondence imaging (CI method using a sorting technique. Different from the conventional CI schemes, the bucket detector signals (BDS are first processed by a differential technique, and then sorted in a descending (or ascending order. Subsequently, according to the front and last several frames of the sorted BDS, the positive and negative subsets (PNS are created by selecting the relative frames from the reference detector signals. Finally, the object image is recovered from the PNS. Besides, an adaptive method based on two-step iteration is designed to select the optimum number of frames. To verify the proposed method, a single-detector computational ghost imaging (GI setup is constructed. We experimentally and numerically compare the performance of the proposed method with different GI algorithms. The results show that our method can improve the reconstruction quality and reduce the computation cost by using fewer measurement data.

  15. A hybrid approach to protein differential expression in mass spectrometry-based proteomics

    KAUST Repository

    Wang, X.

    2012-04-19

    MOTIVATION: Quantitative mass spectrometry-based proteomics involves statistical inference on protein abundance, based on the intensities of each protein\\'s associated spectral peaks. However, typical MS-based proteomics datasets have substantial proportions of missing observations, due at least in part to censoring of low intensities. This complicates intensity-based differential expression analysis. RESULTS: We outline a statistical method for protein differential expression, based on a simple Binomial likelihood. By modeling peak intensities as binary, in terms of \\'presence/absence,\\' we enable the selection of proteins not typically amenable to quantitative analysis; e.g. \\'one-state\\' proteins that are present in one condition but absent in another. In addition, we present an analysis protocol that combines quantitative and presence/absence analysis of a given dataset in a principled way, resulting in a single list of selected proteins with a single-associated false discovery rate. AVAILABILITY: All R code available here: http://www.stat.tamu.edu/~adabney/share/xuan_code.zip.

  16. Trajectory data privacy protection based on differential privacy mechanism

    Science.gov (United States)

    Gu, Ke; Yang, Lihao; Liu, Yongzhi; Liao, Niandong

    2018-05-01

    In this paper, we propose a trajectory data privacy protection scheme based on differential privacy mechanism. In the proposed scheme, the algorithm first selects the protected points from the user’s trajectory data; secondly, the algorithm forms the polygon according to the protected points and the adjacent and high frequent accessed points that are selected from the accessing point database, then the algorithm calculates the polygon centroids; finally, the noises are added to the polygon centroids by the differential privacy method, and the polygon centroids replace the protected points, and then the algorithm constructs and issues the new trajectory data. The experiments show that the running time of the proposed algorithms is fast, the privacy protection of the scheme is effective and the data usability of the scheme is higher.

  17. Differential Search Coils Based Magnetometers: Conditioning, Magnetic Sensitivity, Spatial Resolution

    Directory of Open Access Journals (Sweden)

    Timofeeva Maria

    2012-03-01

    Full Text Available A theoretical and experimental comparison of optimized search coils based magnetometers, operating either in the Flux mode or in the classical Lenz-Faraday mode, is presented. The improvements provided by the Flux mode in terms of bandwidth and measuring range of the sensor are detailed. Theory, SPICE model and measurements are in good agreement. The spatial resolution of the sensor is studied which is an important parameter for applications in non destructive evaluation. A general expression of the magnetic sensitivity of search coils sensors is derived. Solutions are proposed to design magnetometers with reduced weight and volume without degrading the magnetic sensitivity. An original differential search coil based magnetometer, made of coupled coils, operating in flux mode and connected to a differential transimpedance amplifier is proposed. It is shown that this structure is better in terms of volume occupancy than magnetometers using two separated coils without any degradation in magnetic sensitivity. Experimental results are in good agreement with calculations.

  18. Differential geometry based solvation model II: Lagrangian formulation.

    Science.gov (United States)

    Chen, Zhan; Baker, Nathan A; Wei, G W

    2011-12-01

    Solvation is an elementary process in nature and is of paramount importance to more sophisticated chemical, biological and biomolecular processes. The understanding of solvation is an essential prerequisite for the quantitative description and analysis of biomolecular systems. This work presents a Lagrangian formulation of our differential geometry based solvation models. The Lagrangian representation of biomolecular surfaces has a few utilities/advantages. First, it provides an essential basis for biomolecular visualization, surface electrostatic potential map and visual perception of biomolecules. Additionally, it is consistent with the conventional setting of implicit solvent theories and thus, many existing theoretical algorithms and computational software packages can be directly employed. Finally, the Lagrangian representation does not need to resort to artificially enlarged van der Waals radii as often required by the Eulerian representation in solvation analysis. The main goal of the present work is to analyze the connection, similarity and difference between the Eulerian and Lagrangian formalisms of the solvation model. Such analysis is important to the understanding of the differential geometry based solvation model. The present model extends the scaled particle theory of nonpolar solvation model with a solvent-solute interaction potential. The nonpolar solvation model is completed with a Poisson-Boltzmann (PB) theory based polar solvation model. The differential geometry theory of surfaces is employed to provide a natural description of solvent-solute interfaces. The optimization of the total free energy functional, which encompasses the polar and nonpolar contributions, leads to coupled potential driven geometric flow and PB equations. Due to the development of singularities and nonsmooth manifolds in the Lagrangian representation, the resulting potential-driven geometric flow equation is embedded into the Eulerian representation for the purpose of

  19. Differential alkylation-based redox proteomics – Lessons learnt

    Science.gov (United States)

    Wojdyla, Katarzyna; Rogowska-Wrzesinska, Adelina

    2015-01-01

    Cysteine is one of the most reactive amino acids. This is due to the electronegativity of sulphur atom in the side chain of thiolate group. It results in cysteine being present in several distinct redox forms inside the cell. Amongst these, reversible oxidations, S-nitrosylation and S-sulfenylation are crucial mediators of intracellular redox signalling, with known associations to health and disease. Study of their functionalities has intensified thanks to the development of various analytical strategies, with particular contribution from differential alkylation-based proteomics methods. Presented here is a critical evaluation of differential alkylation-based strategies for the analysis of S-nitrosylation and S-sulfenylation. The aim is to assess the current status and to provide insights for future directions in the dynamically evolving field of redox proteomics. To achieve that we collected 35 original research articles published since 2010 and analysed them considering the following parameters, (i) resolution of modification site, (ii) quantitative information, including correction of modification levels by protein abundance changes and determination of modification site occupancy, (iii) throughput, including the amount of starting material required for analysis. The results of this meta-analysis are the core of this review, complemented by issues related to biological models and sample preparation in redox proteomics, including conditions for free thiol blocking and labelling of target cysteine oxoforms. PMID:26282677

  20. A paper-based scaffold for enhanced osteogenic differentiation of equine adipose-derived stem cells.

    Science.gov (United States)

    Petersen, Gayle F; Hilbert, Bryan J; Trope, Gareth D; Kalle, Wouter H J; Strappe, Padraig M

    2015-11-01

    We investigated the applicability of single layer paper-based scaffolds for the three-dimensional (3D) growth and osteogenic differentiation of equine adipose-derived stem cells (EADSC), with comparison against conventional two-dimensional (2D) culture on polystyrene tissue culture vessels. Viable culture of EADSC was achieved using paper-based scaffolds, with EADSC grown and differentiated in 3D culture retaining high cell viability (>94 %), similarly to EADSC in 2D culture. Osteogenic differentiation of EADSC was significantly enhanced in 3D culture, with Alizarin Red S staining and quantification demonstrating increased mineralisation (p < 0.0001), and an associated increase in expression of the osteogenic-specific markers alkaline phosphatase (p < 0.0001), osteopontin (p < 0.0001), and runx2 (p < 0.01). Furthermore, scanning electron microscopy revealed a spherical morphology of EADSC in 3D culture, compared to a flat morphology of EADSC in 2D culture. Single layer paper-based scaffolds provide an enhanced environment for the in vitro 3D growth and osteogenic differentiation of EADSC, with high cell viability, and a spherical morphology.

  1. Graphene nanomesh-based devices exhibiting a strong negative differential conductance effect

    International Nuclear Information System (INIS)

    Hung Nguyen, V; Mazzamuto, F; Saint-Martin, J; Bournel, A; Dollfus, P

    2012-01-01

    Using atomistic quantum simulation based on a tight binding model, we have investigated the transport characteristics of graphene nanomesh-based devices and evaluated the possibilities of observing negative differential conductance. It is shown that by taking advantage of bandgap opening in the graphene nanomesh lattice, a strong negative differential conductance effect can be achieved at room temperature in pn junctions and n-doped structures. Remarkably, the effect is improved very significantly (with a peak-to-valley current ratio of a few hundred) and appears to be weakly sensitive to the transition length in graphene nanomesh pn hetero-junctions when inserting a pristine (gapless) graphene section in the transition region between n and p zones. The study therefore suggests new design strategies for graphene electronic devices which may offer strong advantages in terms of performance and processing over the devices studied previously. (paper)

  2. Harnessing cellular differentiation to improve ALA-based photodynamic therapy in an artificial skin model

    Science.gov (United States)

    Maytin, Edward; Anand, Sanjay; Sato, Nobuyuki; Mack, Judith; Ortel, Bernhard

    2005-04-01

    During ALA-based photodynamic therapy (PDT), a pro-drug (aminolevulinic acid; ALA) is taken up by tumor cells and metabolically converted to a photosensitizing intermediate (protoporphyrin IX; PpIX). ALA-based PDT, while an emerging treatment modality, remains suboptimal for most cancers (e.g. squamous cell carcinoma of the skin). Many treatment failures may be largely due to insufficient conversion of ALA to PpIX within cells. We discovered a novel way to increase the conversion of ALA to PpIX, by administering agents that can drive terminal differentiation (i.e., accelerate cellular maturation). Terminally-differentiated epithelial cells show higher levels of intracellular PpIX, apparently via increased levels of a rate-limiting enzyme, coproporphyrinogen oxidase (CPO). To study these mechanisms in a three-dimensional tissue, we developed an organotypic model that mimics true epidermal physiology in a majority of respects. A line of rat epidermal keratinocytes (REKs), when grown in raft cultures, displays all the features of a fully-differentiated epidermis. Addition of ALA to the culture medium results in ALA uptake and PpIX synthesis, with subsequent death of keratinocytes upon exposure to blue light. Using this model, we can manipulate cellular differentiation via three different approaches. (1) Vitamin D, a hormone that enhances keratinocyte differentiation; (2) Hoxb13, a nuclear transcription factor that affects the genetically-controlled differentiation program of stratifying cells (3) Hyaluronan, an abundant extracellular matrix molecule that regulates epidermal differentiation. Because the raft cultures contain only a single cell type (no blood, fibroblasts, etc.) the effects of terminal differentiation upon CPO, PpIX, and keratinocyte cell death can be specifically defined.

  3. Differential BPFs with Multiple Transmission Zeros Based on Terminated Coupled Lines

    Science.gov (United States)

    Niu, Yiming; Yang, Guo; Wu, Wen

    2018-04-01

    Differential bandpass filters (BPFs) named Filter A and Filter B based on Terminated Coupled Lines (TCLs) are proposed in this letter. The TCLs contributes to not only three poles in differential-mode (DM) for wideband filtering response but also multiple zeros in both DM and common-mode (CM) offering wide DM out-of-band rejection and good CM suppression. Fabricated filters centred at 3.5 GHz with wide DM passband and wideband CM suppression have been designed and measured. The filters improved the noise suppression capability of the communication and radiometer systems. The simulated and measured results are in good agreement.

  4. Gelatin-Based Hydrogels Promote Chondrogenic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stem Cells In Vitro

    Science.gov (United States)

    Salamon, Achim; van Vlierberghe, Sandra; van Nieuwenhove, Ine; Baudisch, Frank; Graulus, Geert-Jan; Benecke, Verena; Alberti, Kristin; Neumann, Hans-Georg; Rychly, Joachim; Martins, José C.; Dubruel, Peter; Peters, Kirsten

    2014-01-01

    Due to the weak regeneration potential of cartilage, there is a high clinical incidence of articular joint disease, leading to a strong demand for cartilaginous tissue surrogates. The aim of this study was to evaluate a gelatin-based hydrogel for its suitability to support chondrogenic differentiation of human mesenchymal stem cells. Gelatin-based hydrogels are biodegradable, show high biocompatibility, and offer possibilities to introduce functional groups and/or ligands. In order to prove their chondrogenesis-supporting potential, a hydrogel film was developed and compared with standard cell culture polystyrene regarding the differentiation behavior of human mesenchymal stem cells. Cellular basis for this study were human adipose tissue-derived mesenchymal stem cells, which exhibit differentiation potential along the adipogenic, osteogenic and chondrogenic lineage. The results obtained show a promotive effect of gelatin-based hydrogels on chondrogenic differentiation of mesenchymal stem cells in vitro and therefore encourage subsequent in vivo studies. PMID:28788517

  5. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-01-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current–voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research. PMID:27819264

  6. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-11-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current-voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research.

  7. Pulse retrieval algorithm for interferometric frequency-resolved optical gating based on differential evolution.

    Science.gov (United States)

    Hyyti, Janne; Escoto, Esmerando; Steinmeyer, Günter

    2017-10-01

    A novel algorithm for the ultrashort laser pulse characterization method of interferometric frequency-resolved optical gating (iFROG) is presented. Based on a genetic method, namely, differential evolution, the algorithm can exploit all available information of an iFROG measurement to retrieve the complex electric field of a pulse. The retrieval is subjected to a series of numerical tests to prove the robustness of the algorithm against experimental artifacts and noise. These tests show that the integrated error-correction mechanisms of the iFROG method can be successfully used to remove the effect from timing errors and spectrally varying efficiency in the detection. Moreover, the accuracy and noise resilience of the new algorithm are shown to outperform retrieval based on the generalized projections algorithm, which is widely used as the standard method in FROG retrieval. The differential evolution algorithm is further validated with experimental data, measured with unamplified three-cycle pulses from a mode-locked Ti:sapphire laser. Additionally introducing group delay dispersion in the beam path, the retrieval results show excellent agreement with independent measurements with a commercial pulse measurement device based on spectral phase interferometry for direct electric-field retrieval. Further experimental tests with strongly attenuated pulses indicate resilience of differential-evolution-based retrieval against massive measurement noise.

  8. HYPERDIRE HYPERgeometric functions DIfferential REduction. Mathematica-based packages for the differential reduction of generalized hypergeometric functions. Lauricella function F{sub C} of three variables

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Joint Institute for Nuclear Research, Dubna (Russian Federation); Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2016-12-15

    We present a further extension of the HYPERDIRE project, which is devoted to the creation of a set of Mathematica-based program packages for manipulations with Horn-type hypergeometric functions on the basis of differential equations. Specifically, we present the implementation of the differential reduction for the Lauricella function F{sub C} of three variables.

  9. Gelatin-Based Hydrogels Promote Chondrogenic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stem Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Achim Salamon

    2014-02-01

    Full Text Available Due to the weak regeneration potential of cartilage, there is a high clinical incidence of articular joint disease, leading to a strong demand for cartilaginous tissue surrogates. The aim of this study was to evaluate a gelatin-based hydrogel for its suitability to support chondrogenic differentiation of human mesenchymal stem cells. Gelatin-based hydrogels are biodegradable, show high biocompatibility, and offer possibilities to introduce functional groups and/or ligands. In order to prove their chondrogenesis-supporting potential, a hydrogel film was developed and compared with standard cell culture polystyrene regarding the differentiation behavior of human mesenchymal stem cells. Cellular basis for this study were human adipose tissue-derived mesenchymal stem cells, which exhibit differentiation potential along the adipogenic, osteogenic and chondrogenic lineage. The results obtained show a promotive effect of gelatin-based hydrogels on chondrogenic differentiation of mesenchymal stem cells in vitro and therefore encourage subsequent in vivo studies.

  10. Morphology-based prediction of osteogenic differentiation potential of human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Fumiko Matsuoka

    Full Text Available Human bone marrow mesenchymal stem cells (hBMSCs are widely used cell source for clinical bone regeneration. Achieving the greatest therapeutic effect is dependent on the osteogenic differentiation potential of the stem cells to be implanted. However, there are still no practical methods to characterize such potential non-invasively or previously. Monitoring cellular morphology is a practical and non-invasive approach for evaluating osteogenic potential. Unfortunately, such image-based approaches had been historically qualitative and requiring experienced interpretation. By combining the non-invasive attributes of microscopy with the latest technology allowing higher throughput and quantitative imaging metrics, we studied the applicability of morphometric features to quantitatively predict cellular osteogenic potential. We applied computational machine learning, combining cell morphology features with their corresponding biochemical osteogenic assay results, to develop prediction model of osteogenic differentiation. Using a dataset of 9,990 images automatically acquired by BioStation CT during osteogenic differentiation culture of hBMSCs, 666 morphometric features were extracted as parameters. Two commonly used osteogenic markers, alkaline phosphatase (ALP activity and calcium deposition were measured experimentally, and used as the true biological differentiation status to validate the prediction accuracy. Using time-course morphological features throughout differentiation culture, the prediction results highly correlated with the experimentally defined differentiation marker values (R>0.89 for both marker predictions. The clinical applicability of our morphology-based prediction was further examined with two scenarios: one using only historical cell images and the other using both historical images together with the patient's own cell images to predict a new patient's cellular potential. The prediction accuracy was found to be greatly enhanced

  11. Transcriptomics-based identification of developmental toxicants through their interference with cardiomyocyte differentiation of embryonic stem cells

    International Nuclear Information System (INIS)

    Dartel, Dorien A.M. van; Pennings, Jeroen L.A.; Schooten, Frederik J. van; Piersma, Aldert H.

    2010-01-01

    The embryonic stem cell test (EST) predicts developmental toxicity based on the inhibition of cardiomyocyte differentiation of embryonic stem cells (ESC). The subjective endpoint, the long culture duration together with the undefined applicability domain and related predictivity need further improvement to facilitate implementation of the EST into regulatory strategies. These aspects may be improved by studying gene expression changes in the ESC differentiation cultures and their modulation by compound exposure using transcriptomics. Here, we tested the developmental toxicants monobutyl phthalate and 6-aminonicotinamide. ESC were allowed to differentiated, and cardiomyocyte differentiation was assessed after 10 days of culture. RNA of solvent controls was collected after 0, 24, 48, 72 and 96 h of exposure, and RNA of developmental-toxicant-exposed cultures was collected after 24 and 96 h. Samples were hybridized to DNA microarrays, and 1355 genes were found differentially expressed among the unexposed experimental groups. These regulated genes were involved in differentiation-related processes, and Principal Component Analysis (PCA) based on these genes showed that the unexposed experimental groups appeared in chronological order in the PCA, which can therefore be regarded as a continuous representation of the differentiation track. The developmental-toxicant-exposed cultures appeared to deviate significantly from this differentiation track, which confirms the compound-modulating effects on the differentiation process. The incorporation of transcriptomics in the EST is expected to provide a more informative and improved endpoint in the EST as compared with morphology, allowing early detection of differentiation modulation. Furthermore, this approach may improve the definition of the applicability domain and predictivity of the EST.

  12. Design of Novel FBG-Based Sensor of Differential Pressure with Magnetic Transfer

    Directory of Open Access Journals (Sweden)

    Guohui Lyu

    2017-02-01

    Full Text Available In this paper, a differential pressure sensor with magnetic transfer is proposed, in which the non-electric measurement based on the fiber Bragg grating (FBG with the position limiting mechanism is implemented without the direct contact of the sensing unit with the measuring fluid. The test shows that the designed sensor is effective for measuring differential pressure in the range of 0~10 kPa with a sensitivity of 0.0112 nm/kPa, which can be used in environments with high temperature, strong corrosion and high overload measurements.

  13. Design of Novel FBG-Based Sensor of Differential Pressure with Magnetic Transfer.

    Science.gov (United States)

    Lyu, Guohui; Che, Guohang; Li, Junqing; Jiang, Xu; Wang, Keda; Han, Yueqiang; Gao, Laixu

    2017-02-15

    In this paper, a differential pressure sensor with magnetic transfer is proposed, in which the non-electric measurement based on the fiber Bragg grating (FBG) with the position limiting mechanism is implemented without the direct contact of the sensing unit with the measuring fluid. The test shows that the designed sensor is effective for measuring differential pressure in the range of 0~10 kPa with a sensitivity of 0.0112 nm/kPa, which can be used in environments with high temperature, strong corrosion and high overload measurements.

  14. Transcriptome-based differentiation of closely-related Miscanthus lines.

    Directory of Open Access Journals (Sweden)

    Philippe Chouvarine

    Full Text Available BACKGROUND: Distinguishing between individuals is critical to those conducting animal/plant breeding, food safety/quality research, diagnostic and clinical testing, and evolutionary biology studies. Classical genetic identification studies are based on marker polymorphisms, but polymorphism-based techniques are time and labor intensive and often cannot distinguish between closely related individuals. Illumina sequencing technologies provide the detailed sequence data required for rapid and efficient differentiation of related species, lines/cultivars, and individuals in a cost-effective manner. Here we describe the use of Illumina high-throughput exome sequencing, coupled with SNP mapping, as a rapid means of distinguishing between related cultivars of the lignocellulosic bioenergy crop giant miscanthus (Miscanthus × giganteus. We provide the first exome sequence database for Miscanthus species complete with Gene Ontology (GO functional annotations. RESULTS: A SNP comparative analysis of rhizome-derived cDNA sequences was successfully utilized to distinguish three Miscanthus × giganteus cultivars from each other and from other Miscanthus species. Moreover, the resulting phylogenetic tree generated from SNP frequency data parallels the known breeding history of the plants examined. Some of the giant miscanthus plants exhibit considerable sequence divergence. CONCLUSIONS: Here we describe an analysis of Miscanthus in which high-throughput exome sequencing was utilized to differentiate between closely related genotypes despite the current lack of a reference genome sequence. We functionally annotated the exome sequences and provide resources to support Miscanthus systems biology. In addition, we demonstrate the use of the commercial high-performance cloud computing to do computational GO annotation.

  15. Constraint Differentiation

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander; Basin, David; Viganò, Luca

    2010-01-01

    We introduce constraint differentiation, a powerful technique for reducing search when model-checking security protocols using constraint-based methods. Constraint differentiation works by eliminating certain kinds of redundancies that arise in the search space when using constraints to represent...... results show that constraint differentiation substantially reduces search and considerably improves the performance of OFMC, enabling its application to a wider class of problems....

  16. Random number generation based on digital differential chaos

    KAUST Repository

    Zidan, Mohammed A.

    2012-07-29

    In this paper, we present a fully digital differential chaos based random number generator. The output of the digital circuit is proved to be chaotic by calculating the output time series maximum Lyapunov exponent. We introduce a new post processing technique to improve the distribution and statistical properties of the generated data. The post-processed output passes the NIST Sp. 800-22 statistical tests. The system is written in Verilog VHDL and realized on Xilinx Virtex® FPGA. The generator can fit into a very small area and have a maximum throughput of 2.1 Gb/s.

  17. Introduction of the Notion of Differential Equations by Modelling Based Teaching

    Science.gov (United States)

    Budinski, Natalija; Takaci, Djurdjica

    2011-01-01

    This paper proposes modelling based learning as a tool for learning and teaching mathematics. The example of modelling real world problems leading to the exponential function as the solution of differential equations is described, as well as the observations about students' activities during the process. The students were acquainted with the…

  18. A high-throughput surface plasmon resonance biosensor based on differential interferometric imaging

    International Nuclear Information System (INIS)

    Wang, Daqian; Ding, Lili; Zhang, Wei; Zhang, Enyao; Yu, Xinglong; Luo, Zhaofeng; Ou, Huichao

    2012-01-01

    A new high-throughput surface plasmon resonance (SPR) biosensor based on differential interferometric imaging is reported. The two SPR interferograms of the sensing surface are imaged on two CCD cameras. The phase difference between the two interferograms is 180°. The refractive index related factor (RIRF) of the sensing surface is calculated from the two simultaneously acquired interferograms. The simulation results indicate that the RIRF exhibits a linear relationship with the refractive index of the sensing surface and is unaffected by the noise, drift and intensity distribution of the light source. The affinity and kinetic information can be extracted in real time from continuously acquired RIRF distributions. The results of refractometry experiments show that the dynamic detection range of SPR differential interferometric imaging system can be over 0.015 refractive index unit (RIU). High refractive index resolution is down to 0.45 RU (1 RU = 1 × 10 −6 RIU). Imaging and protein microarray experiments demonstrate the ability of high-throughput detection. The aptamer experiments demonstrate that the SPR sensor based on differential interferometric imaging has a great capability to be implemented for high-throughput aptamer kinetic evaluation. These results suggest that this biosensor has the potential to be utilized in proteomics and drug discovery after further improvement. (paper)

  19. Absolute Position Sensing Based on a Robust Differential Capacitive Sensor with a Grounded Shield Window

    Directory of Open Access Journals (Sweden)

    Yang Bai

    2016-05-01

    Full Text Available A simple differential capacitive sensor is provided in this paper to measure the absolute positions of length measuring systems. By utilizing a shield window inside the differential capacitor, the measurement range and linearity range of the sensor can reach several millimeters. What is more interesting is that this differential capacitive sensor is only sensitive to one translational degree of freedom (DOF movement, and immune to the vibration along the other two translational DOFs. In the experiment, we used a novel circuit based on an AC capacitance bridge to directly measure the differential capacitance value. The experimental result shows that this differential capacitive sensor has a sensitivity of 2 × 10−4 pF/μm with 0.08 μm resolution. The measurement range of this differential capacitive sensor is 6 mm, and the linearity error are less than 0.01% over the whole absolute position measurement range.

  20. Design of an ultrafast all-optical differentiator based on a fiber Bragg grating in transmission.

    Science.gov (United States)

    Preciado, Miguel A; Muriel, Miguel A

    2008-11-01

    We propose and analyze a first-order optical differentiator based on a fiber Bragg grating (FBG) in transmission. It is shown in the examples that a simple uniform-period FBG in a very strong coupling regime (maximum reflectivity very close to 100%) can perform close to ideal temporal differentiation of the complex envelope of an arbitrary-input optical signal.

  1. Dip-in Indicators for Visual Differentiation of Fuel Mixtures Based on Wettability of Fluoroalkylchlorosilane-Coated Inverse Opal Films.

    Science.gov (United States)

    Sedighi, Abootaleb; Qiu, Shuang; Wong, Michael C K; Li, Paul C H

    2015-12-30

    We have developed the dip-in indicator based on the inverse opal film (IOF) for visual differentiation of organic liquid mixtures, such as oil/gasoline or ethanol/gasoline fuel mixtures. The IOF consists of a three-dimensional porous structure with a highly ordered periodic arrangement of nanopores. The specularly reflected light at the interface of the nanopores and silica walls contributes to the structural color of the IOF film. This color disappears when the nanopores are infiltrated by a liquid with a similar refractive index to silica. The disappearance of the structural color provides a means to differentiate various liquid fuel mixtures based on their wettability of the nanopores in the IOF-based indicators. For differentiation of various liquid mixtures, we tune the wettability threshold of the indicator in such a way that it is wetted (color disappears) by one liquid but is not wetted by the other (color remains). Although colorimetric differentiation of liquids based on IOF wettability has been reported, differentiation of highly similar liquid mixtures require complicated readout approaches. It is known that the IOF wettability is controlled by multiple surface properties (e.g., oleophobicity) and structural properties (e.g., neck angle and film thickness) of the nanostructure. Therefore, we aim to exploit the combined tuning of these properties for differentiation of fuel mixtures with close compositions. In this study, we have demonstrated that, for the first time, the IOF-based dip-in indicator is able to detect a slight difference in the fuel mixture composition (i.e., 0.4% of oil content). Moreover, the color/no-color differentiation platform is simple, powerful, and easy-to-read. This platform makes the dip-in indicator a promising tool for authentication and determination of fuel composition at the point-of-purchase or point-of-use.

  2. Fast and quantitative differentiation of single-base mismatched DNA by initial reaction rate of catalytic hairpin assembly.

    Science.gov (United States)

    Li, Chenxi; Li, Yixin; Xu, Xiao; Wang, Xinyi; Chen, Yang; Yang, Xiaoda; Liu, Feng; Li, Na

    2014-10-15

    The widely used catalytic hairpin assembly (CHA) amplification strategy generally needs several hours to accomplish one measurement based on the prevailingly used maximum intensity detection mode, making it less practical for assays where high throughput or speed is desired. To make the best use of the kinetic specificity of toehold domain for circuit reaction initiation, we developed a mathematical model and proposed an initial reaction rate detection mode to quantitatively differentiate the single-base mismatch. Using the kinetic mode, assay time can be reduced substantially to 10 min for one measurement with the comparable sensitivity and single-base mismatch differentiating ability as were obtained by the maximum intensity detection mode. This initial reaction rate based approach not only provided a fast and quantitative differentiation of single-base mismatch, but also helped in-depth understanding of the CHA system, which will be beneficial to the design of highly sensitive and specific toehold-mediated hybridization reactions. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Lectures on differential Galois theory

    CERN Document Server

    Magid, Andy R

    1994-01-01

    Differential Galois theory studies solutions of differential equations over a differential base field. In much the same way that ordinary Galois theory is the theory of field extensions generated by solutions of (one variable) polynomial equations, differential Galois theory looks at the nature of the differential field extension generated by the solutions of differential equations. An additional feature is that the corresponding differential Galois groups (of automorphisms of the extension fixing the base and commuting with the derivation) are algebraic groups. This book deals with the differential Galois theory of linear homogeneous differential equations, whose differential Galois groups are algebraic matrix groups. In addition to providing a convenient path to Galois theory, this approach also leads to the constructive solution of the inverse problem of differential Galois theory for various classes of algebraic groups. Providing a self-contained development and many explicit examples, this book provides ...

  4. Agent-Based Model of Price Competition and Product Differentiation on Congested Networks

    OpenAIRE

    Lei Zhang; David Levinson; Shanjiang Zhu

    2007-01-01

    Using consistent agent-based techniques, this research models the decision-making processes of users and infrastructure owner/operators to explore the welfare consequence of price competition, capacity choice, and product differentiation on congested transportation networks. Component models include: (1) An agent-based travel demand model wherein each traveler has learning capabilities and unique characteristics (e.g. value of time); (2) Econometric facility provision cost models; and (3) Rep...

  5. Modification of species-based differential evolution for multimodal optimization

    Science.gov (United States)

    Idrus, Said Iskandar Al; Syahputra, Hermawan; Firdaus, Muliawan

    2015-12-01

    At this time optimization has an important role in various fields as well as between other operational research, industry, finance and management. Optimization problem is the problem of maximizing or minimizing a function of one variable or many variables, which include unimodal and multimodal functions. Differential Evolution (DE), is a random search technique using vectors as an alternative solution in the search for the optimum. To localize all local maximum and minimum on multimodal function, this function can be divided into several domain of fitness using niching method. Species-based niching method is one of method that build sub-populations or species in the domain functions. This paper describes the modification of species-based previously to reduce the computational complexity and run more efficiently. The results of the test functions show species-based modifications able to locate all the local optima in once run the program.

  6. The effect of numerical techniques on differential equation based chaotic generators

    KAUST Repository

    Zidan, Mohammed A.

    2012-07-29

    In this paper, we study the effect of the numerical solution accuracy on the digital implementation of differential chaos generators. Four systems are built on a Xilinx Virtex 4 FPGA using Euler, mid-point, and Runge-Kutta fourth order techniques. The twelve implementations are compared based on the FPGA used area, maximum throughput, maximum Lyapunov exponent, and autocorrelation confidence region. Based on circuit performance and the chaotic response of the different implementations, it was found that less complicated numerical solution has better chaotic response and higher throughput.

  7. Differential standard deviation of log-scale intensity based optical coherence tomography angiography.

    Science.gov (United States)

    Shi, Weisong; Gao, Wanrong; Chen, Chaoliang; Yang, Victor X D

    2017-12-01

    In this paper, a differential standard deviation of log-scale intensity (DSDLI) based optical coherence tomography angiography (OCTA) is presented for calculating microvascular images of human skin. The DSDLI algorithm calculates the variance in difference images of two consecutive log-scale intensity based structural images from the same position along depth direction to contrast blood flow. The en face microvascular images were then generated by calculating the standard deviation of the differential log-scale intensities within the specific depth range, resulting in an improvement in spatial resolution and SNR in microvascular images compared to speckle variance OCT and power intensity differential method. The performance of DSDLI was testified by both phantom and in vivo experiments. In in vivo experiments, a self-adaptive sub-pixel image registration algorithm was performed to remove the bulk motion noise, where 2D Fourier transform was utilized to generate new images with spatial interval equal to half of the distance between two pixels in both fast-scanning and depth directions. The SNRs of signals of flowing particles are improved by 7.3 dB and 6.8 dB on average in phantom and in vivo experiments, respectively, while the average spatial resolution of images of in vivo blood vessels is increased by 21%. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The Characterization Tool: A knowledge-based stem cell, differentiated cell, and tissue database with a web-based analysis front-end.

    NARCIS (Netherlands)

    I. Wohlers (Inken); H. Stachelscheid; J. Borstlap; K. Zeilinger; J.C. Gerlach

    2009-01-01

    htmlabstractIn the rapidly growing field of stem cell research, there is a need for universal databases and web-based applications that provide a common knowledge base on the characteristics of stem cells, differentiated cells, and tissues by collecting, processing, and making available diverse

  9. A regression-based differential expression detection algorithm for microarray studies with ultra-low sample size.

    Directory of Open Access Journals (Sweden)

    Daniel Vasiliu

    Full Text Available Global gene expression analysis using microarrays and, more recently, RNA-seq, has allowed investigators to understand biological processes at a system level. However, the identification of differentially expressed genes in experiments with small sample size, high dimensionality, and high variance remains challenging, limiting the usability of these tens of thousands of publicly available, and possibly many more unpublished, gene expression datasets. We propose a novel variable selection algorithm for ultra-low-n microarray studies using generalized linear model-based variable selection with a penalized binomial regression algorithm called penalized Euclidean distance (PED. Our method uses PED to build a classifier on the experimental data to rank genes by importance. In place of cross-validation, which is required by most similar methods but not reliable for experiments with small sample size, we use a simulation-based approach to additively build a list of differentially expressed genes from the rank-ordered list. Our simulation-based approach maintains a low false discovery rate while maximizing the number of differentially expressed genes identified, a feature critical for downstream pathway analysis. We apply our method to microarray data from an experiment perturbing the Notch signaling pathway in Xenopus laevis embryos. This dataset was chosen because it showed very little differential expression according to limma, a powerful and widely-used method for microarray analysis. Our method was able to detect a significant number of differentially expressed genes in this dataset and suggest future directions for investigation. Our method is easily adaptable for analysis of data from RNA-seq and other global expression experiments with low sample size and high dimensionality.

  10. Design of Test Wrapper Scan Chain Based on Differential Evolution

    Directory of Open Access Journals (Sweden)

    Aijun Zhu

    2013-08-01

    Full Text Available Integrated Circuit has entered the era of design of the IP-based SoC (System on Chip, which makes the IP core reuse become a key issue. SoC test wrapper design for scan chain is a NP Hard problem, we propose an algorithm based on Differential Evolution (DE to design wrapper scan chain. Through group’s mutation, crossover and selection operations, the design of test wrapper scan chain is achieved. Experimental verification is carried out according to the international standard benchmark ITC’02. The results show that the algorithm can obtain shorter longest wrapper scan chains, compared with other algorithms.

  11. A novel algorithm for discrimination between inrush current and internal faults in power transformer differential protection based on discrete wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    Eldin, A.A. Hossam; Refaey, M.A. [Electrical Engineering Department, Alexandria University, Alexandria (Egypt)

    2011-01-15

    This paper proposes a novel methodology for transformer differential protection, based on wave shape recognition of the discriminating criterion extracted of the instantaneous differential currents. Discrete wavelet transform has been applied to the differential currents due to internal fault and inrush currents. The diagnosis criterion is based on median absolute deviation (MAD) of wavelet coefficients over a specified frequency band. The proposed algorithm is examined using various simulated inrush and internal fault current cases on a power transformer that has been modeled using electromagnetic transients program EMTDC software. Results of evaluation study show that, proposed wavelet based differential protection scheme can discriminate internal faults from inrush currents. (author)

  12. Investigating market efficiency through a forecasting model based on differential equations

    Science.gov (United States)

    de Resende, Charlene C.; Pereira, Adriano C. M.; Cardoso, Rodrigo T. N.; de Magalhães, A. R. Bosco

    2017-05-01

    A new differential equation based model for stock price trend forecast is proposed as a tool to investigate efficiency in an emerging market. Its predictive power showed statistically to be higher than the one of a completely random model, signaling towards the presence of arbitrage opportunities. Conditions for accuracy to be enhanced are investigated, and application of the model as part of a trading strategy is discussed.

  13. A sandwich-like differential B-dot based on EACVD polycrystalline diamond slice

    Science.gov (United States)

    Xu, P.; Yu, Y.; Xu, L.; Zhou, H. Y.; Qiu, C. J.

    2018-06-01

    In this article, we present a method of mass production of a standardized high-performance differential B-dot magnetic probe together with the magnetic field measurement in a pulsed current device with the current up to hundreds of kilo-Amperes. A polycrystalline diamond slice produced in an Electron Assisted Chemical Vapor Deposition device is used as the base and insulating material to imprint two symmetric differential loops for the magnetic field measurement. The SP3 carbon bond in the cubic lattice structure of diamond is confirmed by Raman spectra. The thickness of this slice is 20 μm. A gold loop is imprinted onto each surface of the slice by using the photolithography technique. The inner diameter, width, and thickness of each loop are 0.8 mm, 50 μm, and 1 μm, respectively. It provides a way of measuring the pulsed magnetic field with a high spatial and temporal resolution, especially in limited space. This differential magnetic probe has demonstrated a very good common-mode rejection rate through the pulsed magnetic field measurement.

  14. Quartz crystal microbalance-based system for high-sensitivity differential sputter yield measurements

    International Nuclear Information System (INIS)

    Rubin, B.; Topper, J. L.; Farnell, C. C.; Yalin, A. P.

    2009-01-01

    We present a quartz crystal microbalance-based system for high sensitivity differential sputter yield measurements of different target materials due to ion bombardment. The differential sputter yields can be integrated to find total yields. Possible ion beam conditions include ion energies in the range of 30-350 eV and incidence angles of 0 deg. - 70 deg. from normal. A four-grid ion optics system is used to achieve a collimated ion beam at low energy (<100 eV) and a two-grid ion optics is used for higher energies (up to 750 eV). A complementary weight loss approach is also used to measure total sputter yields. Validation experiments are presented that confirm high sensitivity and accuracy of sputter yield measurements.

  15. Testing a model of codependency for college students in Taiwan based on Bowen's concept of differentiation.

    Science.gov (United States)

    Chang, Shih-Hua

    2018-04-01

    The purpose of this study was to test a model of codependency based on Bowen's concept of differentiation for college students in Taiwan. The relations between family-of-origin dysfunction, differentiation of self, codependency traits and related symptoms including low self-esteem, relationship distress and psychological adjustment problems were examined. Data were collected from 567 college students from 2 large, urban universities in northern Taiwan. Results indicated a significantly negative relationship between levels of codependency and self-differentiation and that self-differentiation partially mediated the relationship between family-of-origin dysfunction and codependency. The implications of these findings for counselling Taiwanese college students who experience codependency traits and related symptoms as well as suggestions for future research are discussed. © 2016 International Union of Psychological Science.

  16. Detection of Individual Molecules and Ions by Carbon Nanotube-Based Differential Resistive Pulse Sensor.

    Science.gov (United States)

    Peng, Ran; Tang, Xiaowu Shirley; Li, Dongqing

    2018-04-01

    This paper presents a new method of sensing single molecules and cations by a carbon nanotube (CNT)-based differential resistive pulse sensing (RPS) technique on a nanofluidic chip. A mathematical model for multichannel RPS systems is developed to evaluate the CNT-based RPS signals. Individual cations, rhodamine B dye molecules, and ssDNAs are detected successfully with high resolution and high signal-to-noise ratio. Differentiating ssDNAs with 15 and 30 nucleotides are achieved. The experimental results also show that translocation of negatively charged ssDNAs through a CNT decreases the electrical resistance of the CNT channel, while translocation of positively charged cations and rhodamine B molecules increases the electrical resistance of the CNT. The CNT-based nanofluidic device developed in this work provides a new avenue for single-molecule/ion detection and offers a potential strategy for DNA sequencing. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A Lateral Differential Resonant Pressure Microsensor Based on SOI-Glass Wafer-Level Vacuum Packaging

    Directory of Open Access Journals (Sweden)

    Bo Xie

    2015-09-01

    Full Text Available This paper presents the fabrication and characterization of a resonant pressure microsensor based on SOI-glass wafer-level vacuum packaging. The SOI-based pressure microsensor consists of a pressure-sensitive diaphragm at the handle layer and two lateral resonators (electrostatic excitation and capacitive detection on the device layer as a differential setup. The resonators were vacuum packaged with a glass cap using anodic bonding and the wire interconnection was realized using a mask-free electrochemical etching approach by selectively patterning an Au film on highly topographic surfaces. The fabricated resonant pressure microsensor with dual resonators was characterized in a systematic manner, producing a quality factor higher than 10,000 (~6 months, a sensitivity of about 166 Hz/kPa and a reduced nonlinear error of 0.033% F.S. Based on the differential output, the sensitivity was increased to two times and the temperature-caused frequency drift was decreased to 25%.

  18. Tie Points Extraction for SAR Images Based on Differential Constraints

    Science.gov (United States)

    Xiong, X.; Jin, G.; Xu, Q.; Zhang, H.

    2018-04-01

    Automatically extracting tie points (TPs) on large-size synthetic aperture radar (SAR) images is still challenging because the efficiency and correct ratio of the image matching need to be improved. This paper proposes an automatic TPs extraction method based on differential constraints for large-size SAR images obtained from approximately parallel tracks, between which the relative geometric distortions are small in azimuth direction and large in range direction. Image pyramids are built firstly, and then corresponding layers of pyramids are matched from the top to the bottom. In the process, the similarity is measured by the normalized cross correlation (NCC) algorithm, which is calculated from a rectangular window with the long side parallel to the azimuth direction. False matches are removed by the differential constrained random sample consensus (DC-RANSAC) algorithm, which appends strong constraints in azimuth direction and weak constraints in range direction. Matching points in the lower pyramid images are predicted with the local bilinear transformation model in range direction. Experiments performed on ENVISAT ASAR and Chinese airborne SAR images validated the efficiency, correct ratio and accuracy of the proposed method.

  19. Living biointerfaces based on non-pathogenic bacteria to direct cell differentiation

    Science.gov (United States)

    Rodrigo-Navarro, Aleixandre; Rico, Patricia; Saadeddin, Anas; Garcia, Andres J.; Salmeron-Sanchez, Manuel

    2014-07-01

    Genetically modified Lactococcus lactis, non-pathogenic bacteria expressing the FNIII7-10 fibronectin fragment as a protein membrane have been used to create a living biointerface between synthetic materials and mammalian cells. This FNIII7-10 fragment comprises the RGD and PHSRN sequences of fibronectin to bind α5β1 integrins and triggers signalling for cell adhesion, spreading and differentiation. We used L. lactis strain to colonize material surfaces and produce stable biofilms presenting the FNIII7-10 fragment readily available to cells. Biofilm density is easily tunable and remains stable for several days. Murine C2C12 myoblasts seeded over mature biofilms undergo bipolar alignment and form differentiated myotubes, a process triggered by the FNIII7-10 fragment. This biointerface based on living bacteria can be further modified to express any desired biochemical signal, establishing a new paradigm in biomaterial surface functionalisation for biomedical applications.

  20. Method of Monitoring Urban Area Deformation Based on Differential TomoSAR

    Directory of Open Access Journals (Sweden)

    WANG Aichun

    2016-12-01

    Full Text Available While the use of differential TomoSAR based on compressive sensing (CS makes it possible to solve the layover problem and reconstruct the deformation information of an observed urban area scene acquired by moderate-high resolution SAR satellite, the performance of the reconstruction decreases for a sparse and structural observed scene due to ignoring the structural characteristics of the observed scene. To deal with this issue, the method for differential SAR tomography based on Khatri-Rao subspace and block compressive sensing (KRS-BCS is proposed. The proposed method changes the reconstruction of the sparse and structural observed scene into a BCS problem under Khatri-Rao subspace, using the structure information of the observed scene and Khatri-Rao product property of the reconstructed observation matrix for differential TomoSAR, such that the KRS-BCS problem is efficiently solved with a block sparse l1/l2 norm optimization signal model, and the performance of resolution capability and reconstruction estimation is compared and analyzed qualitatively and quantitatively by the theoretical analysis and the simulation experiments, all of the results show the propose KRS-BCS method practicably overcomes the problems of CS method, as well as, quite maintains the high resolution characteristics, effectively reduces the probability of false scattering target and greatly improves the reconstruction accurate of scattering point. Finally, the application is taking the urban area of the Mobara(in Chiba, Japan as the test area and using 34 ENVISAT-ASAR images, the accuracy is verifying with the reference deformations derived from first level point data and GPS tracking data, the results show the trend is consistent and the overall deviation is small between reconstruction deformations of the propose KRS-BCS method and the reference deformations, and the accuracy is high in the estimation of the urban area deformation.

  1. A test of the California competency-based differentiated role model.

    Science.gov (United States)

    Keating, Sarah B; Rutledge, Dana N; Sargent, Arlene; Walker, Polly

    2003-01-01

    To address the incongruence between the expectations of nursing service and education in California, the Education Industry Interface Task Force of the California Strategic Planning Committee for Nursing developed descriptions to assist employers and educators in clearly differentiating practice and educational competencies. The completion of the Competency-Based Role Differentiation Model resulted in the need to test the model for its utility in the service setting, in education, and for career planning for nurses. Three alpha demonstration sites were selected based on representative geographical regions of California. The sites were composed of tri-partnerships consisting of a medical center, an associate degree in nursing program, and a baccalaureate nursing program. Observers rated senior students and new graduates in medical-surgical units on their behaviors in teacher and leadership care provider and care coordinator roles. The alpha demonstration study results were as expected. That is, senior students practice predominantly at a novice level in teacher and management/leadership care provider functions and new graduates practice predominately at the competent level. New graduates are more likely to take on novice and competent care coordinator roles. The CBRDM may be useful for practice and education settings to evaluate student and nurse performance, to define role expectations, and to identify the preparation necessary for the roles. It is useful for all of nursing as it continues to define its levels of practice and their relationship to on-the-job performance, curriculum development, and carrier planning.

  2. X-Ray Pulsar Profile Recovery Based on Tracking-Differentiator

    Directory of Open Access Journals (Sweden)

    Dapeng Zhang

    2016-01-01

    Full Text Available The profile recovery is an important work in X-ray pulsar-based navigation. It is a key step for the analysis on the pulsar signal’s characteristic and the computing of time of arrival (TOA. This paper makes an argument for an algorithm based on the tracking-differentiator (TD to recover the profile from the low Signal-to-Noise Ratio (SNR signals. In the method, a TD filter with cascade structure is designed which has very low phase delay and amplitude distortion. In the simulation experiment, two typical pulsars (PSR B0531+21 and PSR B1937+21 are used to verify the algorithm’s performance. The simulation results show that the method satisfies the application requirements in the aspects of SNR and profile fidelity. By processing the data collected by the Rossi X-Ray Timing Explorer (RXTE satellite in space, similar results can also be achieved.

  3. A new capacitive long-range displacement nanometer sensor with differential sensing structure based on time-grating

    Science.gov (United States)

    Yu, Zhicheng; Peng, Kai; Liu, Xiaokang; Pu, Hongji; Chen, Ziran

    2018-05-01

    High-precision displacement sensors, which can measure large displacements with nanometer resolution, are key components in many ultra-precision fabrication machines. In this paper, a new capacitive nanometer displacement sensor with differential sensing structure is proposed for long-range linear displacement measurements based on an approach denoted time grating. Analytical models established using electric field coupling theory and an area integral method indicate that common-mode interference will result in a first-harmonic error in the measurement results. To reduce the common-mode interference, the proposed sensor design employs a differential sensing structure, which adopts a second group of induction electrodes spatially separated from the first group of induction electrodes by a half-pitch length. Experimental results based on a prototype sensor demonstrate that the measurement accuracy and the stability of the sensor are substantially improved after adopting the differential sensing structure. Finally, a prototype sensor achieves a measurement accuracy of  ±200 nm over the full 200 mm measurement range of the sensor.

  4. Generalized query-based active learning to identify differentially methylated regions in DNA.

    Science.gov (United States)

    Haque, Md Muksitul; Holder, Lawrence B; Skinner, Michael K; Cook, Diane J

    2013-01-01

    Active learning is a supervised learning technique that reduces the number of examples required for building a successful classifier, because it can choose the data it learns from. This technique holds promise for many biological domains in which classified examples are expensive and time-consuming to obtain. Most traditional active learning methods ask very specific queries to the Oracle (e.g., a human expert) to label an unlabeled example. The example may consist of numerous features, many of which are irrelevant. Removing such features will create a shorter query with only relevant features, and it will be easier for the Oracle to answer. We propose a generalized query-based active learning (GQAL) approach that constructs generalized queries based on multiple instances. By constructing appropriately generalized queries, we can achieve higher accuracy compared to traditional active learning methods. We apply our active learning method to find differentially DNA methylated regions (DMRs). DMRs are DNA locations in the genome that are known to be involved in tissue differentiation, epigenetic regulation, and disease. We also apply our method on 13 other data sets and show that our method is better than another popular active learning technique.

  5. Improving sensitivity of linear regression-based cell type-specific differential expression deconvolution with per-gene vs. global significance threshold.

    Science.gov (United States)

    Glass, Edmund R; Dozmorov, Mikhail G

    2016-10-06

    The goal of many human disease-oriented studies is to detect molecular mechanisms different between healthy controls and patients. Yet, commonly used gene expression measurements from blood samples suffer from variability of cell composition. This variability hinders the detection of differentially expressed genes and is often ignored. Combined with cell counts, heterogeneous gene expression may provide deeper insights into the gene expression differences on the cell type-specific level. Published computational methods use linear regression to estimate cell type-specific differential expression, and a global cutoff to judge significance, such as False Discovery Rate (FDR). Yet, they do not consider many artifacts hidden in high-dimensional gene expression data that may negatively affect linear regression. In this paper we quantify the parameter space affecting the performance of linear regression (sensitivity of cell type-specific differential expression detection) on a per-gene basis. We evaluated the effect of sample sizes, cell type-specific proportion variability, and mean squared error on sensitivity of cell type-specific differential expression detection using linear regression. Each parameter affected variability of cell type-specific expression estimates and, subsequently, the sensitivity of differential expression detection. We provide the R package, LRCDE, which performs linear regression-based cell type-specific differential expression (deconvolution) detection on a gene-by-gene basis. Accounting for variability around cell type-specific gene expression estimates, it computes per-gene t-statistics of differential detection, p-values, t-statistic-based sensitivity, group-specific mean squared error, and several gene-specific diagnostic metrics. The sensitivity of linear regression-based cell type-specific differential expression detection differed for each gene as a function of mean squared error, per group sample sizes, and variability of the proportions

  6. TIE POINTS EXTRACTION FOR SAR IMAGES BASED ON DIFFERENTIAL CONSTRAINTS

    Directory of Open Access Journals (Sweden)

    X. Xiong

    2018-04-01

    Full Text Available Automatically extracting tie points (TPs on large-size synthetic aperture radar (SAR images is still challenging because the efficiency and correct ratio of the image matching need to be improved. This paper proposes an automatic TPs extraction method based on differential constraints for large-size SAR images obtained from approximately parallel tracks, between which the relative geometric distortions are small in azimuth direction and large in range direction. Image pyramids are built firstly, and then corresponding layers of pyramids are matched from the top to the bottom. In the process, the similarity is measured by the normalized cross correlation (NCC algorithm, which is calculated from a rectangular window with the long side parallel to the azimuth direction. False matches are removed by the differential constrained random sample consensus (DC-RANSAC algorithm, which appends strong constraints in azimuth direction and weak constraints in range direction. Matching points in the lower pyramid images are predicted with the local bilinear transformation model in range direction. Experiments performed on ENVISAT ASAR and Chinese airborne SAR images validated the efficiency, correct ratio and accuracy of the proposed method.

  7. Stepwise Analysis of Differential Item Functioning Based on Multiple-Group Partial Credit Model.

    Science.gov (United States)

    Muraki, Eiji

    1999-01-01

    Extended an Item Response Theory (IRT) method for detection of differential item functioning to the partial credit model and applied the method to simulated data using a stepwise procedure. Then applied the stepwise DIF analysis based on the multiple-group partial credit model to writing trend data from the National Assessment of Educational…

  8. Numerical solution of modified differential equations based on symmetry preservation.

    Science.gov (United States)

    Ozbenli, Ersin; Vedula, Prakash

    2017-12-01

    In this paper, we propose a method to construct invariant finite-difference schemes for solution of partial differential equations (PDEs) via consideration of modified forms of the underlying PDEs. The invariant schemes, which preserve Lie symmetries, are obtained based on the method of equivariant moving frames. While it is often difficult to construct invariant numerical schemes for PDEs due to complicated symmetry groups associated with cumbersome discrete variable transformations, we note that symmetries associated with more convenient transformations can often be obtained by appropriately modifying the original PDEs. In some cases, modifications to the original PDEs are also found to be useful in order to avoid trivial solutions that might arise from particular selections of moving frames. In our proposed method, modified forms of PDEs can be obtained either by addition of perturbation terms to the original PDEs or through defect correction procedures. These additional terms, whose primary purpose is to enable symmetries with more convenient transformations, are then removed from the system by considering moving frames for which these specific terms go to zero. Further, we explore selection of appropriate moving frames that result in improvement in accuracy of invariant numerical schemes based on modified PDEs. The proposed method is tested using the linear advection equation (in one- and two-dimensions) and the inviscid Burgers' equation. Results obtained for these tests cases indicate that numerical schemes derived from the proposed method perform significantly better than existing schemes not only by virtue of improvement in numerical accuracy but also due to preservation of qualitative properties or symmetries of the underlying differential equations.

  9. Modulating functions-based method for parameters and source estimation in one-dimensional partial differential equations

    KAUST Repository

    Asiri, Sharefa M.; Laleg-Kirati, Taous-Meriem

    2016-01-01

    In this paper, modulating functions-based method is proposed for estimating space–time-dependent unknowns in one-dimensional partial differential equations. The proposed method simplifies the problem into a system of algebraic equations linear

  10. Proximity-based differential single cell analysis of the niche to identify stem/progenitor cell regulators

    Science.gov (United States)

    Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Celso, Cristina Lo; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-fu; Scadden, David T

    2016-01-01

    SUMMARY Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on differential single-cell gene expression analysis of mesenchymal osteolineage cells close to and further removed from hematopoietic stem/progenitor cells to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. Amongst the genes which were preferentially expressed in proximal cells, we functionally examined three secreted or cell surface molecules not previously connected to HSPC biology: the secreted RNase Angiogenin, the cytokine IL18 and the adhesion molecule Embigin and discovered that all of these factors are HSPC quiescence regulators. Our proximity-based differential single cell approach therefore reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance understanding of microenvironmental regulation of stem cell function. PMID:27524439

  11. A robust random number generator based on differential comparison of chaotic laser signals.

    Science.gov (United States)

    Zhang, Jianzhong; Wang, Yuncai; Liu, Ming; Xue, Lugang; Li, Pu; Wang, Anbang; Zhang, Mingjiang

    2012-03-26

    We experimentally realize a robust real-time random number generator by differentially comparing the signal from a chaotic semiconductor laser and its delayed signal through a 1-bit analog-to-digital converter. The probability density distribution of the output chaotic signal based on the differential comparison method possesses an extremely small coefficient of Pearson's median skewness (1.5 × 10⁻⁶), which can yield a balanced random sequence much easily than the previously reported method that compares the signal from the chaotic laser with a certain threshold value. Moveover, we experimently demonstrate that our method can stably generate good random numbers at rates of 1.44 Gbit/s with excellent immunity from external perturbations while the previously reported method fails.

  12. Differential Rationality and Personal Development.

    Science.gov (United States)

    Fincher, Cameron

    This publication discusses differential rationality; it asserts that the development of institutions, professions, and individuals involves the differentiation of forms and styles of thinking and knowing that are, in various ways, idiosyncratic. Based on this understanding, differential rationality can be seen as a developmental construct that…

  13. Design of high-order all-optical temporal differentiators based on multiple-phase-shifted fiber Bragg gratings.

    Science.gov (United States)

    Kulishov, Mykola; Azaña, José

    2007-05-14

    A simple and general approach for designing practical all-optical (all-fiber) arbitrary-order time differentiators is introduced here for the first time. Specifically, we demonstrate that the Nth time derivative of an input optical waveform can be obtained by reflection of this waveform in a single uniform fiber Bragg grating (FBG) incorporating N &pi-phase shifts properly located along its grating profile. The general design procedure of an arbitrary-order optical time differentiator based on a multiple-phase-shifted FBG is described and numerically demonstrated for up to fourth-order time differentiation. Our simulations show that the proposed approach can provide optical operation bandwidths in the tens-of-GHz regime using readily feasible FBG structures.

  14. Investigation into the Influence of Physician for Treatment Based on Syndrome Differentiation

    Directory of Open Access Journals (Sweden)

    Lijie Jiang

    2013-01-01

    Full Text Available Background. The characteristics of treatment based on syndrome differentiation (TBSD cause great challenges to evaluate the effectiveness of the clinical methods. Objectives. This paper aims to evaluate the influence of physician to personalized medicine in the process of TBSD. Methods. We performed a randomized, triple-blind trial involving patients of primary insomnia treated by 3 physicians individually and independently. The patients (n=30 were randomly assigned to receive treatments by the 3 physicians for every visit. However, they always received the treatment, respectively, prescribed by the physician at the first visit. The primary outcome was evaluated, respectively, by the Pittsburgh Sleep Quality Index (PSQI and the TCM symptoms measuring scale. The clinical practices of the physicians were recorded at every visit including diagnostic information, syndrome differentiation, treating principles, and prescriptions. Results. All patients in the 3 groups (30 patients showed significant improvements (>66% according to the PSQI and TCM symptoms measuring scale. Conclusion. The results indicate that although with comparable effectiveness, there exist significant differences in syndrome differentiation, the treating principles, and the prescriptions of the approaches used by the 3 physicians. This means that the physician should be considered as an important factor for individualized medicine and the related TCM clinical research.

  15. Image denoising using new pixon representation based on fuzzy filtering and partial differential equations

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Nikpour, Mohsen

    2012-01-01

    In this paper, we have proposed two extensions to pixon-based image modeling. The first one is using bicubic interpolation instead of bilinear interpolation and the second one is using fuzzy filtering method, aiming to improve the quality of the pixonal image. Finally, partial differential...

  16. A genome-wide methylation study on obesity: differential variability and differential methylation.

    Science.gov (United States)

    Xu, Xiaojing; Su, Shaoyong; Barnes, Vernon A; De Miguel, Carmen; Pollock, Jennifer; Ownby, Dennis; Shi, Hidong; Zhu, Haidong; Snieder, Harold; Wang, Xiaoling

    2013-05-01

    Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common complex disease. We analyzed genome-wide methylation profiles of over 470,000 CpGs in peripheral blood samples from 48 obese and 48 lean African-American youth aged 14-20 y old. A substantial number of differentially variable CpG sites (DVCs), using statistics based on variances, as well as a substantial number of differentially methylated CpG sites (DMCs), using statistics based on means, were identified. Similar to the findings in cancers, DVCs generally exhibited an outlier structure and were more variable in cases than in controls. By randomly splitting the current sample into a discovery and validation set, we observed that both the DVCs and DMCs identified from the first set could independently predict obesity status in the second set. Furthermore, both the genes harboring DMCs and the genes harboring DVCs showed significant enrichment of genes identified by genome-wide association studies on obesity and related diseases, such as hypertension, dyslipidemia, type 2 diabetes and certain types of cancers, supporting their roles in the etiology and pathogenesis of obesity. We generalized the recent finding on methylation variability in cancer research to obesity and demonstrated that differential variability is also an important feature of obesity-related methylation changes. Future studies on the epigenetics of obesity will benefit from both statistics based on means and statistics based on variances.

  17. Terahertz-wave differential detection based on simultaneous dual-wavelength up-conversion

    Directory of Open Access Journals (Sweden)

    Yuma Takida

    2017-03-01

    Full Text Available We report a terahertz (THz-wave differential detection based on simultaneous dual-wavelength up-conversion in a nonlinear optical MgO:LiNbO3 crystal with optical and electronic THz-wave sources. The broadband parametric gain and noncollinear phase-matching of MgO:LiNbO3 provide efficient conversion from superposed THz waves to spatially distributed near-infrared (NIR beams to function as a dispersive THz-wave spectrometer without any additional dispersive element. We show that the μW-level THz waves from two independent sources, a 0.78-THz injection-seeded THz-wave parametric generator (is-TPG and a 1.14-THz resonant tunneling diode (RTD, are simultaneously up-converted to two NIR waves and then detected with two NIR photodetectors. By applying a balanced detection scheme to this dual-frequency detection, we demonstrate THz-wave differential imaging of maltose and polyethylene pellets in the transmission geometry. This dual-wavelength detection is applicable to more than three frequencies and broadband THz-wave radiation for real-time THz-wave spectroscopic detection and imaging.

  18. The development of differential inductors using double air-bridge structure based on integrated passive device technology

    Science.gov (United States)

    Li, Yang; Yao, Zhao; Fu, Xiao-Qian; Li, Zhi-Ming; Shan, Fu-Kai; Wang, Cong

    2017-05-01

    Recently, integrated passive devices have become increasingly popular; inductor realization, in particular, offers interesting high performance for RF modules and systems. In this paper, a development of differential inductor fabricated by integrated passive devices technology using a double air-bridge structure is presented. A study of the model development of the differential inductor is first demonstrated. In this model section, a segment box analysis method is applied to provide a clear presentation of the differential inductor. Compared with other work that only shows a brief description of the process, the integrated passive devices process used to fabricate the inductor in this study is elaborated on. Finally, a characterization of differential inductors with different physical layout parameters is illustrated based on inductance and quality factors, which provides a valuable reference for realizing high performance. The proposed work provides a good solution for the design, fabrication and practical application of RF modules and systems.

  19. Interrogation of weak Bragg grating sensors based on dual-wavelength differential detection.

    Science.gov (United States)

    Cheng, Rui; Xia, Li

    2016-11-15

    It is shown that for weak Bragg gratings the logarithmic ratio of reflected intensities at any two wavelengths within the spectrum follows a linear relationship with the Bragg wavelength shift, with a slope proportional to their wavelength spacing. This finding is exploited to develop a flexible, efficient, and cheap interrogation solution of weak fiber Bragg grating (FBGs), especially ultra-short FBGs, in distributed sensing based on dual-wavelength differential detection. The concept is experimentally studied in both single and distributed sensing systems with ultra-short FBG sensors. The work may form the basis of new and promising FBG interrogation techniques based on detecting discrete rather than continuous spectra.

  20. Differential evolution enhanced with multiobjective sorting-based mutation operators.

    Science.gov (United States)

    Wang, Jiahai; Liao, Jianjun; Zhou, Ying; Cai, Yiqiao

    2014-12-01

    Differential evolution (DE) is a simple and powerful population-based evolutionary algorithm. The salient feature of DE lies in its mutation mechanism. Generally, the parents in the mutation operator of DE are randomly selected from the population. Hence, all vectors are equally likely to be selected as parents without selective pressure at all. Additionally, the diversity information is always ignored. In order to fully exploit the fitness and diversity information of the population, this paper presents a DE framework with multiobjective sorting-based mutation operator. In the proposed mutation operator, individuals in the current population are firstly sorted according to their fitness and diversity contribution by nondominated sorting. Then parents in the mutation operators are proportionally selected according to their rankings based on fitness and diversity, thus, the promising individuals with better fitness and diversity have more opportunity to be selected as parents. Since fitness and diversity information is simultaneously considered for parent selection, a good balance between exploration and exploitation can be achieved. The proposed operator is applied to original DE algorithms, as well as several advanced DE variants. Experimental results on 48 benchmark functions and 12 real-world application problems show that the proposed operator is an effective approach to enhance the performance of most DE algorithms studied.

  1. Differential Diagnosis of Cystic Lymphangioma of the Pancreas Based on Imaging Features

    Directory of Open Access Journals (Sweden)

    Ting-Kai Leung

    2006-01-01

    Full Text Available Lymphangioma is a benign tumor, which is a consequence of lymphatic malformation with blockage of lymphatic flow. Most lymphangiomas occur in the neck and axillary region, and < 1% occur in the mesentery or retroperitoneum. Lymphangiomas arising from the pancreas are extremely rare. We report the case of a 34-year-old woman with cystic lymphangioma of the pancreas without major symptoms or signs. A 6 × 6 cm intra-abdominal cystic mass was incidentally revealed by sonography during a health examination. It is always a challenge to differentiate the lesion from other possible cystic-like pancreatic neoplasms. Differential diagnosis of cystic lymphangioma from other cystic-like tumors of the pancreas can be performed based on their imaging characteristics, including presence of septa, cystic or wall calcification, soft tissue, wall thickness, single or multiple loculation, and dilatation of the pancreatic duct. Post-gadolinium magnetic resonance imaging is excellent in defining the origin of intra-abdominal cystic mass and intracystic septa.

  2. Estimating the parameters of stochastic differential equations using a criterion function based on the Kolmogorov-Smirnov statistic

    OpenAIRE

    McDonald, A. David; Sandal, Leif Kristoffer

    1998-01-01

    Estimation of parameters in the drift and diffusion terms of stochastic differential equations involves simulation and generally requires substantial data sets. We examine a method that can be applied when available time series are limited to less than 20 observations per replication. We compare and contrast parameter estimation for linear and nonlinear first-order stochastic differential equations using two criterion functions: one based on a Chi-square statistic, put forward by Hurn and Lin...

  3. Proximity-Based Differential Single-Cell Analysis of the Niche to Identify Stem/Progenitor Cell Regulators.

    Science.gov (United States)

    Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel A; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Lo Celso, Cristina; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-Fu; Scadden, David T

    2016-10-06

    Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on the differential single-cell gene expression analysis of mesenchymal osteolineage cells close to, and further removed from, hematopoietic stem/progenitor cells (HSPCs) to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. We functionally examined, among the genes that were preferentially expressed in proximal cells, three secreted or cell-surface molecules not previously connected to HSPC biology-the secreted RNase angiogenin, the cytokine IL18, and the adhesion molecule Embigin-and discovered that all of these factors are HSPC quiescence regulators. Therefore, our proximity-based differential single-cell approach reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance the understanding of microenvironmental regulation of stem cell function. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Expressions of pathologic markers in PRP based chondrogenic differentiation of human adipose derived stem cells.

    Science.gov (United States)

    Pakfar, Arezou; Irani, Shiva; Hanaee-Ahvaz, Hana

    2017-02-01

    Optimization of the differentiation medium through using autologous factors such as PRP is of great consideration, but due to the complex, variable and undefined composition of PRP on one hand and lack of control over the absolute regulatory mechanisms in in vitro conditions or disrupted and different mechanisms in diseased tissue microenvironments in in vivo conditions on the other hand, it is complicated and rather unpredictable to get the desired effects of PRP making it inevitable to monitor the possible pathologic or undesired differentiation pathways and therapeutic effects of PRP. Therefore, in this study the probable potential of PRP on inducing calcification, inflammation and angiogenesis in chondrogenically-differentiated cells was investigated. The expressions of chondrogenic, inflammatory, osteogenic and angiogenic markers from TGFβ or PRP-treated cells during chondrogenic differentiation of human adipose-derived stem cells (ADSCs) was evaluated. Expressions of Collagen II (Col II), Aggrecan, Sox9 and Runx2 were quantified using q-RT PCR. Expression of Col II and X was investigated by immunocytochemistry as well. Glycosaminoglycans (GAGs) production was also determined by GAG assay. Possible angiogenic/inflammatory potential was determined by quantitatively measuring the secreted VEGF, TNFα and phosphorylated VEGFR2 via ELISA. In addition, the calcification of the construct was monitored by measuring ALP activity and calcium deposition. Our data showed that PRP positively induced chondrogenesis; meanwhile the secretion of angiogenic and inflammatory markers was decreased. VEGFR2 phosphorylation and ALP activity had a decreasing trend, but tissue mineralization was enhanced upon treating with PRP. Although reduction in inflammatory/angiogenic potential of the chondrogenically differentiated constructs highlights the superior effectiveness of PRP in comparison to TGFβ for chondrogenic differentiation, yet further improvement of the PRP-based

  5. Viscoelastic Plate Analysis Based on Gâteaux Differential

    Directory of Open Access Journals (Sweden)

    Kadıoğlu Fethi

    2016-01-01

    Full Text Available In this study, it is aimed to analyze the quasi-static response of viscoelastic Kirchhoff plates with mixed finite element formulation based on the Gâteaux differential. Although the static response of elastic plate, beam and shell structures is a widely studied topic, there are few studies that exist in the literature pertaining to the analysis of the viscoelastic structural elements especially with complex geometries, loading conditions and constitutive relations. The developed mixed finite element model in transformed Laplace-Carson space has four unknowns as displacement, bending and twisting moments in addition to the dynamic and geometric boundary condition terms. Four-parameter solid model is employed for modelling the viscoelastic behaviour. For transformation of the solutions obtained in the Laplace-Carson domain to the time domain, different numerical inverse transform techniques are employed. The developed solution technique is applied to several quasi-static example problems for the verification of the suggested numerical procedure.

  6. Reward-based spatial crowdsourcing with differential privacy preservation

    Science.gov (United States)

    Xiong, Ping; Zhang, Lefeng; Zhu, Tianqing

    2017-11-01

    In recent years, the popularity of mobile devices has transformed spatial crowdsourcing (SC) into a novel mode for performing complicated projects. Workers can perform tasks at specified locations in return for rewards offered by employers. Existing methods ensure the efficiency of their systems by submitting the workers' exact locations to a centralised server for task assignment, which can lead to privacy violations. Thus, implementing crowsourcing applications while preserving the privacy of workers' location is a key issue that needs to be tackled. We propose a reward-based SC method that achieves acceptable utility as measured by task assignment success rates, while efficiently preserving privacy. A differential privacy model ensures rigorous privacy guarantee, and Laplace noise is introduced to protect workers' exact locations. We then present a reward allocation mechanism that adjusts each piece of the reward for a task using the distribution of the workers' locations. Through experimental results, we demonstrate that this optimised-reward method is efficient for SC applications.

  7. Differential evolution algorithm-based kernel parameter selection for Fukunaga-Koontz Transform subspaces construction

    Science.gov (United States)

    Binol, Hamidullah; Bal, Abdullah; Cukur, Huseyin

    2015-10-01

    The performance of the kernel based techniques depends on the selection of kernel parameters. That's why; suitable parameter selection is an important problem for many kernel based techniques. This article presents a novel technique to learn the kernel parameters in kernel Fukunaga-Koontz Transform based (KFKT) classifier. The proposed approach determines the appropriate values of kernel parameters through optimizing an objective function constructed based on discrimination ability of KFKT. For this purpose we have utilized differential evolution algorithm (DEA). The new technique overcomes some disadvantages such as high time consumption existing in the traditional cross-validation method, and it can be utilized in any type of data. The experiments for target detection applications on the hyperspectral images verify the effectiveness of the proposed method.

  8. Surface Crack Detection for Carbon Fiber Reinforced Plastic Materials Using Pulsed Eddy Current Based on Rectangular Differential Probe

    Directory of Open Access Journals (Sweden)

    Jialong Wu

    2014-01-01

    Full Text Available Aiming at the surface defect inspection of carbon fiber reinforced composite, the differential and the direct measurement finite element simulation models of pulsed eddy current flaw detection were built. The principle of differential pulsed eddy current detection was analyzed and the sensitivity of defect detection was compared through two kinds of measurements. The validity of simulation results was demonstrated by experiments. The simulation and experimental results show that the pulsed eddy current detection method based on rectangular differential probe can effectively improve the sensitivity of surface defect detection of carbon fiber reinforced composite material.

  9. An absolute calibration method of an ethyl alcohol biosensor based on wavelength-modulated differential photothermal radiometry.

    Science.gov (United States)

    Liu, Yi Jun; Mandelis, Andreas; Guo, Xinxin

    2015-11-01

    In this work, laser-based wavelength-modulated differential photothermal radiometry (WM-DPTR) is applied to develop a non-invasive in-vehicle alcohol biosensor. WM-DPTR features unprecedented ethanol-specificity and sensitivity by suppressing baseline variations through a differential measurement near the peak and baseline of the mid-infrared ethanol absorption spectrum. Biosensor signal calibration curves are obtained from WM-DPTR theory and from measurements in human blood serum and ethanol solutions diffused from skin. The results demonstrate that the WM-DPTR-based calibrated alcohol biosensor can achieve high precision and accuracy for the ethanol concentration range of 0-100 mg/dl. The high-performance alcohol biosensor can be incorporated into ignition interlocks that could be fitted as a universal accessory in vehicles in an effort to reduce incidents of drinking and driving.

  10. Fast integration-based prediction bands for ordinary differential equation models.

    Science.gov (United States)

    Hass, Helge; Kreutz, Clemens; Timmer, Jens; Kaschek, Daniel

    2016-04-15

    To gain a deeper understanding of biological processes and their relevance in disease, mathematical models are built upon experimental data. Uncertainty in the data leads to uncertainties of the model's parameters and in turn to uncertainties of predictions. Mechanistic dynamic models of biochemical networks are frequently based on nonlinear differential equation systems and feature a large number of parameters, sparse observations of the model components and lack of information in the available data. Due to the curse of dimensionality, classical and sampling approaches propagating parameter uncertainties to predictions are hardly feasible and insufficient. However, for experimental design and to discriminate between competing models, prediction and confidence bands are essential. To circumvent the hurdles of the former methods, an approach to calculate a profile likelihood on arbitrary observations for a specific time point has been introduced, which provides accurate confidence and prediction intervals for nonlinear models and is computationally feasible for high-dimensional models. In this article, reliable and smooth point-wise prediction and confidence bands to assess the model's uncertainty on the whole time-course are achieved via explicit integration with elaborate correction mechanisms. The corresponding system of ordinary differential equations is derived and tested on three established models for cellular signalling. An efficiency analysis is performed to illustrate the computational benefit compared with repeated profile likelihood calculations at multiple time points. The integration framework and the examples used in this article are provided with the software package Data2Dynamics, which is based on MATLAB and freely available at http://www.data2dynamics.org helge.hass@fdm.uni-freiburg.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e

  11. Constructing HVS-Based Optimal Substitution Matrix Using Enhanced Differential Evolution

    Directory of Open Access Journals (Sweden)

    Shu-Fen Tu

    2013-01-01

    Full Text Available Least significant bit (LSB substitution is a method of information hiding. The secret message is embedded into the last k bits of a cover-image in order to evade the notice of hackers. The security and stego-image quality are two main limitations of the LSB substitution method. Therefore, some researchers have proposed an LSB substitution matrix to address these two issues. Finding the optimal LSB substitution matrix can be conceptualized as a problem of combinatorial optimization. In this paper, we adopt a different heuristic method based on other researchers’ method, called enhanced differential evolution (EDE, to construct an optimal LSB substitution matrix. Differing from other researchers, we adopt an HVS-based measurement as a fitness function and embed the secret by modifying the pixel to a closest value rather than simply substituting the LSBs. Our scheme extracts the secret by modular operations as simple LSB substitution does. The experimental results show that the proposed embedding algorithm indeed improves imperceptibility of stego-images substantially.

  12. Low cost, microcontroller based heating device for multi-wavelength differential scanning fluorimetry.

    Science.gov (United States)

    Hoeser, Jo; Gnandt, Emmanuel; Friedrich, Thorsten

    2018-01-23

    Differential scanning fluorimetry is a popular method to estimate the stability of a protein in distinct buffer conditions by determining its 'melting point'. The method requires a temperature controlled fluorescence spectrometer or a RT-PCR machine. Here, we introduce a low-budget version of a microcontroller based heating device implemented into a 96-well plate reader that is connected to a standard fluorescence spectrometer. We demonstrate its potential to determine the 'melting point' of soluble and membranous proteins at various buffer conditions.

  13. Simulating Chemical Kinetics Without Differential Equations: A Quantitative Theory Based on Chemical Pathways.

    Science.gov (United States)

    Bai, Shirong; Skodje, Rex T

    2017-08-17

    A new approach is presented for simulating the time-evolution of chemically reactive systems. This method provides an alternative to conventional modeling of mass-action kinetics that involves solving differential equations for the species concentrations. The method presented here avoids the need to solve the rate equations by switching to a representation based on chemical pathways. In the Sum Over Histories Representation (or SOHR) method, any time-dependent kinetic observable, such as concentration, is written as a linear combination of probabilities for chemical pathways leading to a desired outcome. In this work, an iterative method is introduced that allows the time-dependent pathway probabilities to be generated from a knowledge of the elementary rate coefficients, thus avoiding the pitfalls involved in solving the differential equations of kinetics. The method is successfully applied to the model Lotka-Volterra system and to a realistic H 2 combustion model.

  14. Culture belief based multi-objective hybrid differential evolutionary algorithm in short term hydrothermal scheduling

    International Nuclear Information System (INIS)

    Zhang Huifeng; Zhou Jianzhong; Zhang Yongchuan; Lu Youlin; Wang Yongqiang

    2013-01-01

    Highlights: ► Culture belief is integrated into multi-objective differential evolution. ► Chaotic sequence is imported to improve evolutionary population diversity. ► The priority of convergence rate is proved in solving hydrothermal problem. ► The results show the quality and potential of proposed algorithm. - Abstract: A culture belief based multi-objective hybrid differential evolution (CB-MOHDE) is presented to solve short term hydrothermal optimal scheduling with economic emission (SHOSEE) problem. This problem is formulated for compromising thermal cost and emission issue while considering its complicated non-linear constraints with non-smooth and non-convex characteristics. The proposed algorithm integrates a modified multi-objective differential evolutionary algorithm into the computation model of culture algorithm (CA) as well as some communication protocols between population space and belief space, three knowledge structures in belief space are redefined according to these problem-solving characteristics, and in the differential evolution a chaotic factor is embedded into mutation operator for avoiding the premature convergence by enlarging the search scale when the search trajectory reaches local optima. Furthermore, a new heuristic constraint-handling technique is utilized to handle those complex equality and inequality constraints of SHOSEE problem. After the application on hydrothermal scheduling system, the efficiency and stability of the proposed CB-MOHDE is verified by its more desirable results in comparison to other method established recently, and the simulation results also reveal that CB-MOHDE can be a promising alternative for solving SHOSEE.

  15. Calculus & ordinary differential equations

    CERN Document Server

    Pearson, David

    1995-01-01

    Professor Pearson's book starts with an introduction to the area and an explanation of the most commonly used functions. It then moves on through differentiation, special functions, derivatives, integrals and onto full differential equations. As with other books in the series the emphasis is on using worked examples and tutorial-based problem solving to gain the confidence of students.

  16. Parameter identification based on modified simulated annealing differential evolution algorithm for giant magnetostrictive actuator

    Science.gov (United States)

    Gao, Xiaohui; Liu, Yongguang

    2018-01-01

    There is a serious nonlinear relationship between input and output in the giant magnetostrictive actuator (GMA) and how to establish mathematical model and identify its parameters is very important to study characteristics and improve control accuracy. The current-displacement model is firstly built based on Jiles-Atherton (J-A) model theory, Ampere loop theorem and stress-magnetism coupling model. And then laws between unknown parameters and hysteresis loops are studied to determine the data-taking scope. The modified simulated annealing differential evolution algorithm (MSADEA) is proposed by taking full advantage of differential evolution algorithm's fast convergence and simulated annealing algorithm's jumping property to enhance the convergence speed and performance. Simulation and experiment results shows that this algorithm is not only simple and efficient, but also has fast convergence speed and high identification accuracy.

  17. Regulation of human mesenchymal stem cells differentiation into chondrocytes in extracellular matrix-based hydrogel scaffolds.

    Science.gov (United States)

    Du, Mingchun; Liang, Hui; Mou, Chenchen; Li, Xiaoran; Sun, Jie; Zhuang, Yan; Xiao, Zhifeng; Chen, Bing; Dai, Jianwu

    2014-02-01

    To induce human mesenchymal stem cells (hMSCs) to differentiate into chondrocytes in three-dimensional (3D) microenvironments, we developed porous hydrogel scaffolds using the cartilage extracellular matrix (ECM) components of chondroitin sulfate (CS) and collagen (COL). The turbidity and viscosity experiments indicated hydrogel could form through pH-triggered co-precipitation when pH=2-3. Enzyme-linked immunosorbent assay (ELISA) confirmed the hydrogel scaffolds could controllably release growth factors as envisaged. Transforming growth factor-β (TGF-β) was released to stimulate hMSCs differentiation into chondrocytes; and then collagen binding domain-basic fibroblast growth factor (CBD-bFGF) was released to improve the differentiation and preserve the chondrocyte phenotype. In in vitro cell culture experiments, the differentiation processes were compared in different microenvironments: 2D culture in culture plate as control, 3D culture in the fabricated scaffolds without growth factors (CC), the samples with CBD-bFGF (CC-C), the samples with TGF-β (CC-T), the samples with CBD-bFGF/TGF-β (CC-CT). Real-time polymerase chain reaction (RT-PCR) revealed the hMSC marker genes of CD44 and CD105 decreased; at the same time the chondrocyte marker genes of collagen type II and aggrecan increased, especially in the CC-CT sample. Immunostaining results further confirmed the hMSC marker protein of CD 44 disappeared and the chondrocyte marker protein of collagen type II emerged over time in the CC-CT sample. These results imply the ECM-based hydrogel scaffolds with growth factors can supply suitable 3D cell niches for hMSCs differentiation into chondrocytes and the differentiation process can be regulated by the controllably released growth factors. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Static and free vibration analysis of carbon nano wires based on Timoshenko beam theory using differential quadrature method

    Directory of Open Access Journals (Sweden)

    Maziar Janghorban

    Full Text Available Static and free vibration analysis of carbon nano wires with rectangular cross section based on Timoshenko beam theory is studied in this research. Differential quadrature method (DQM is employed to solve the governing equations. From the knowledge of author, it is the first time that free vibration of nano wires is investigated. It is also the first time that differential quadrature method is used for bending analysis of nano wires.

  19. An optimized digital watermarking algorithm in wavelet domain based on differential evolution for color image.

    Science.gov (United States)

    Cui, Xinchun; Niu, Yuying; Zheng, Xiangwei; Han, Yingshuai

    2018-01-01

    In this paper, a new color watermarking algorithm based on differential evolution is proposed. A color host image is first converted from RGB space to YIQ space, which is more suitable for the human visual system. Then, apply three-level discrete wavelet transformation to luminance component Y and generate four different frequency sub-bands. After that, perform singular value decomposition on these sub-bands. In the watermark embedding process, apply discrete wavelet transformation to a watermark image after the scrambling encryption processing. Our new algorithm uses differential evolution algorithm with adaptive optimization to choose the right scaling factors. Experimental results show that the proposed algorithm has a better performance in terms of invisibility and robustness.

  20. Clinicopathological and Molecular Histochemical Review of Skull Base Metastasis from Differentiated Thyroid Carcinoma

    International Nuclear Information System (INIS)

    Matsuno, Akira; Murakami, Mineko; Hoya, Katsumi; Yamada, Shoko M.; Miyamoto, Shinya; Yamada, So; Son, Jae-Hyun; Nishido, Hajime; Ide, Fuyuaki; Nagashima, Hiroshi; Sugaya, Mutsumi; Hirohata, Toshio; Mizutani, Akiko; Okinaga, Hiroko; Ishii, Yudo; Tahara, Shigeyuki; Teramoto, Akira; Osamura, R. Yoshiyuki; Yamazaki, Kazuto; Ishida, Yasuo

    2013-01-01

    Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma

  1. Population stochastic modelling (PSM)--an R package for mixed-effects models based on stochastic differential equations.

    Science.gov (United States)

    Klim, Søren; Mortensen, Stig Bousgaard; Kristensen, Niels Rode; Overgaard, Rune Viig; Madsen, Henrik

    2009-06-01

    The extension from ordinary to stochastic differential equations (SDEs) in pharmacokinetic and pharmacodynamic (PK/PD) modelling is an emerging field and has been motivated in a number of articles [N.R. Kristensen, H. Madsen, S.H. Ingwersen, Using stochastic differential equations for PK/PD model development, J. Pharmacokinet. Pharmacodyn. 32 (February(1)) (2005) 109-141; C.W. Tornøe, R.V. Overgaard, H. Agersø, H.A. Nielsen, H. Madsen, E.N. Jonsson, Stochastic differential equations in NONMEM: implementation, application, and comparison with ordinary differential equations, Pharm. Res. 22 (August(8)) (2005) 1247-1258; R.V. Overgaard, N. Jonsson, C.W. Tornøe, H. Madsen, Non-linear mixed-effects models with stochastic differential equations: implementation of an estimation algorithm, J. Pharmacokinet. Pharmacodyn. 32 (February(1)) (2005) 85-107; U. Picchini, S. Ditlevsen, A. De Gaetano, Maximum likelihood estimation of a time-inhomogeneous stochastic differential model of glucose dynamics, Math. Med. Biol. 25 (June(2)) (2008) 141-155]. PK/PD models are traditionally based ordinary differential equations (ODEs) with an observation link that incorporates noise. This state-space formulation only allows for observation noise and not for system noise. Extending to SDEs allows for a Wiener noise component in the system equations. This additional noise component enables handling of autocorrelated residuals originating from natural variation or systematic model error. Autocorrelated residuals are often partly ignored in PK/PD modelling although violating the hypothesis for many standard statistical tests. This article presents a package for the statistical program R that is able to handle SDEs in a mixed-effects setting. The estimation method implemented is the FOCE(1) approximation to the population likelihood which is generated from the individual likelihoods that are approximated using the Extended Kalman Filter's one-step predictions.

  2. Modulating functions-based method for parameters and source estimation in one-dimensional partial differential equations

    KAUST Repository

    Asiri, Sharefa M.

    2016-10-20

    In this paper, modulating functions-based method is proposed for estimating space–time-dependent unknowns in one-dimensional partial differential equations. The proposed method simplifies the problem into a system of algebraic equations linear in unknown parameters. The well-posedness of the modulating functions-based solution is proved. The wave and the fifth-order KdV equations are used as examples to show the effectiveness of the proposed method in both noise-free and noisy cases.

  3. 3D facial expression recognition based on histograms of surface differential quantities

    KAUST Repository

    Li, Huibin

    2011-01-01

    3D face models accurately capture facial surfaces, making it possible for precise description of facial activities. In this paper, we present a novel mesh-based method for 3D facial expression recognition using two local shape descriptors. To characterize shape information of the local neighborhood of facial landmarks, we calculate the weighted statistical distributions of surface differential quantities, including histogram of mesh gradient (HoG) and histogram of shape index (HoS). Normal cycle theory based curvature estimation method is employed on 3D face models along with the common cubic fitting curvature estimation method for the purpose of comparison. Based on the basic fact that different expressions involve different local shape deformations, the SVM classifier with both linear and RBF kernels outperforms the state of the art results on the subset of the BU-3DFE database with the same experimental setting. © 2011 Springer-Verlag.

  4. Partial differential equation-based localization of a monopole source from a circular array.

    Science.gov (United States)

    Ando, Shigeru; Nara, Takaaki; Levy, Tsukassa

    2013-10-01

    Wave source localization from a sensor array has long been the most active research topics in both theory and application. In this paper, an explicit and time-domain inversion method for the direction and distance of a monopole source from a circular array is proposed. The approach is based on a mathematical technique, the weighted integral method, for signal/source parameter estimation. It begins with an exact form of the source-constraint partial differential equation that describes the unilateral propagation of wide-band waves from a single source, and leads to exact algebraic equations that include circular Fourier coefficients (phase mode measurements) as their coefficients. From them, nearly closed-form, single-shot and multishot algorithms are obtained that is suitable for use with band-pass/differential filter banks. Numerical evaluation and several experimental results obtained using a 16-element circular microphone array are presented to verify the validity of the proposed method.

  5. A novel method to identify hub pathways of rheumatoid arthritis based on differential pathway networks.

    Science.gov (United States)

    Wei, Shi-Tong; Sun, Yong-Hua; Zong, Shi-Hua

    2017-09-01

    The aim of the current study was to identify hub pathways of rheumatoid arthritis (RA) using a novel method based on differential pathway network (DPN) analysis. The present study proposed a DPN where protein‑protein interaction (PPI) network was integrated with pathway‑pathway interactions. Pathway data was obtained from background PPI network and the Reactome pathway database. Subsequently, pathway interactions were extracted from the pathway data by building randomized gene‑gene interactions and a weight value was assigned to each pathway interaction using Spearman correlation coefficient (SCC) to identify differential pathway interactions. Differential pathway interactions were visualized using Cytoscape to construct a DPN. Topological analysis was conducted to identify hub pathways that possessed the top 5% degree distribution of DPN. Modules of DPN were mined according to ClusterONE. A total of 855 pathways were selected to build pathway interactions. By filtrating pathway interactions of weight values >0.7, a DPN with 312 nodes and 791 edges was obtained. Topological degree analysis revealed 15 hub pathways, such as heparan sulfate/heparin‑glycosaminoglycan (HS‑GAG) degradation, HS‑GAG metabolism and keratan sulfate degradation for RA based on DPN. Furthermore, hub pathways were also important in modules, which validated the significance of hub pathways. In conclusion, the proposed method is a computationally efficient way to identify hub pathways of RA, which identified 15 hub pathways that may be potential biomarkers and provide insight to future investigation and treatment of RA.

  6. Multi-layer thickness determination using differential-based enhanced Fourier transforms of X-ray reflectivity data

    Energy Technology Data Exchange (ETDEWEB)

    Poust, Benjamin [Department of Materials Science and Engineering, University of California, Los Angeles, CA (United States); Northrop Grumman Space Technology, Redondo Beach, CA (United States); Sandhu, Rajinder [Northrop Grumman Space Technology, Redondo Beach, CA (United States); Goorsky, Mark [Department of Materials Science and Engineering, University of California, Los Angeles, CA (United States)

    2009-08-15

    Layer thickness determination of single and multi-layer structures is achieved using a new method for generating Fourier transforms (FTs) of X-ray reflectivity data. This enhanced Fourier analysis is compared to other techniques in the determination of AlN layer thickness deposited on sapphire. In addition to demonstrably improved results, the results also agree with thicknesses determined using simulations and TEM measurements. The effectiveness of the technique is further demonstrated using the more complicated metamorphic epitaxial multi-layer AlSb/InAs structures deposited on GaAs. The approach reported here is based upon differentiating the specular intensity with respect to the vertical reciprocal space coordinate Q{sub Z}. In general, differentiation is far more effective at removing the sloping background present in reflectivity scans than logarithmic compression alone, average subtraction alone, or other methods. When combined with any of the other enhancement techniques, however, differentiation yields distinguishable discrete Fourier transform (DFT) power spectrum peaks for even the weakest and most truncated of sloping oscillations that are present in many reflectivity scans from multi-layer structures. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  7. CANONICAL BACKWARD DIFFERENTIATION SCHEMES FOR ...

    African Journals Online (AJOL)

    This paper describes a new nonlinear backward differentiation schemes for the numerical solution of nonlinear initial value problems of first order ordinary differential equations. The schemes are based on rational interpolation obtained from canonical polynomials. They are A-stable. The test problems show that they give ...

  8. Measurement-based perturbation theory and differential equation parameter estimation with applications to satellite gravimetry

    Science.gov (United States)

    Xu, Peiliang

    2018-06-01

    The numerical integration method has been routinely used by major institutions worldwide, for example, NASA Goddard Space Flight Center and German Research Center for Geosciences (GFZ), to produce global gravitational models from satellite tracking measurements of CHAMP and/or GRACE types. Such Earth's gravitational products have found widest possible multidisciplinary applications in Earth Sciences. The method is essentially implemented by solving the differential equations of the partial derivatives of the orbit of a satellite with respect to the unknown harmonic coefficients under the conditions of zero initial values. From the mathematical and statistical point of view, satellite gravimetry from satellite tracking is essentially the problem of estimating unknown parameters in the Newton's nonlinear differential equations from satellite tracking measurements. We prove that zero initial values for the partial derivatives are incorrect mathematically and not permitted physically. The numerical integration method, as currently implemented and used in mathematics and statistics, chemistry and physics, and satellite gravimetry, is groundless, mathematically and physically. Given the Newton's nonlinear governing differential equations of satellite motion with unknown equation parameters and unknown initial conditions, we develop three methods to derive new local solutions around a nominal reference orbit, which are linked to measurements to estimate the unknown corrections to approximate values of the unknown parameters and the unknown initial conditions. Bearing in mind that satellite orbits can now be tracked almost continuously at unprecedented accuracy, we propose the measurement-based perturbation theory and derive global uniformly convergent solutions to the Newton's nonlinear governing differential equations of satellite motion for the next generation of global gravitational models. Since the solutions are global uniformly convergent, theoretically speaking

  9. [Phenotype-based primary screening for drugs promoting neuronal subtype differentiation in embryonic stem cells with light microscope].

    Science.gov (United States)

    Gao, Yi-ning; Wang, Dan-ying; Pan, Zong-fu; Mei, Yu-qin; Wang, Zhi-qiang; Zhu, Dan-yan; Lou, Yi-jia

    2012-07-01

    To set up a platform for phenotype-based primary screening of drug candidates promoting neuronal subtype differentiation in embryonic stem cells (ES) with light microscope. Hanging drop culture 4-/4+ method was employed to harvest the cells around embryoid body (EB) at differentiation endpoint. Morphological evaluation for neuron-like cells was performed with light microscope. Axons for more than three times of the length of the cell body were considered as neuron-like cells. The compound(s) that promote neuron-like cells was further evaluated. Icariin (ICA, 10(-6)mol/L) and Isobavachin (IBA, 10(-7)mol/L) were selected to screen the differentiation-promoting activity on ES cells. Immunofluorescence staining with specific antibodies (ChAT, GABA) was used to evaluate the neuron subtypes. The cells treated with IBA showed neuron-like phenotype, but the cells treated with ICA did not exhibit the morphological changes. ES cells treated with IBA was further confirmed to be cholinergic and GABAergic neurons. Phenotypic screening with light microscope for molecules promoting neuronal differentiation is an effective method with advantages of less labor and material consuming and time saving, and false-positive results derived from immunofluorescence can be avoided. The method confirms that IBA is able to facilitate ES cells differentiating into neuronal cells, including cholinergic neurons and GABAergic neurons.

  10. Pulse Retrieval Algorithm for Interferometric Frequency-Resolved Optical Gating Based on Differential Evolution

    OpenAIRE

    Hyyti, Janne; Escoto, Esmerando; Steinmeyer, Günter

    2017-01-01

    A novel algorithm for the ultrashort laser pulse characterization method of interferometric frequency-resolved optical gating (iFROG) is presented. Based on a genetic method, namely differential evolution, the algorithm can exploit all available information of an iFROG measurement to retrieve the complex electric field of a pulse. The retrieval is subjected to a series of numerical tests to prove robustness of the algorithm against experimental artifacts and noise. These tests show that the i...

  11. Systems-based decomposition schemes for the approximate solution of multi-term fractional differential equations

    Science.gov (United States)

    Ford, Neville J.; Connolly, Joseph A.

    2009-07-01

    We give a comparison of the efficiency of three alternative decomposition schemes for the approximate solution of multi-term fractional differential equations using the Caputo form of the fractional derivative. The schemes we compare are based on conversion of the original problem into a system of equations. We review alternative approaches and consider how the most appropriate numerical scheme may be chosen to solve a particular equation.

  12. Automatic differentiation algorithms in model analysis

    NARCIS (Netherlands)

    Huiskes, M.J.

    2002-01-01

    Title: Automatic differentiation algorithms in model analysis
    Author: M.J. Huiskes
    Date: 19 March, 2002

    In this thesis automatic differentiation algorithms and derivative-based methods

  13. Harmony Search Based Parameter Ensemble Adaptation for Differential Evolution

    Directory of Open Access Journals (Sweden)

    Rammohan Mallipeddi

    2013-01-01

    Full Text Available In differential evolution (DE algorithm, depending on the characteristics of the problem at hand and the available computational resources, different strategies combined with a different set of parameters may be effective. In addition, a single, well-tuned combination of strategies and parameters may not guarantee optimal performance because different strategies combined with different parameter settings can be appropriate during different stages of the evolution. Therefore, various adaptive/self-adaptive techniques have been proposed to adapt the DE strategies and parameters during the course of evolution. In this paper, we propose a new parameter adaptation technique for DE based on ensemble approach and harmony search algorithm (HS. In the proposed method, an ensemble of parameters is randomly sampled which form the initial harmony memory. The parameter ensemble evolves during the course of the optimization process by HS algorithm. Each parameter combination in the harmony memory is evaluated by testing them on the DE population. The performance of the proposed adaptation method is evaluated using two recently proposed strategies (DE/current-to-pbest/bin and DE/current-to-gr_best/bin as basic DE frameworks. Numerical results demonstrate the effectiveness of the proposed adaptation technique compared to the state-of-the-art DE based algorithms on a set of challenging test problems (CEC 2005.

  14. Higher-order automatic differentiation of mathematical functions

    Science.gov (United States)

    Charpentier, Isabelle; Dal Cappello, Claude

    2015-04-01

    Functions of mathematical physics such as the Bessel functions, the Chebyshev polynomials, the Gauss hypergeometric function and so forth, have practical applications in many scientific domains. On the one hand, differentiation formulas provided in reference books apply to real or complex variables. These do not account for the chain rule. On the other hand, based on the chain rule, the automatic differentiation has become a natural tool in numerical modeling. Nevertheless automatic differentiation tools do not deal with the numerous mathematical functions. This paper describes formulas and provides codes for the higher-order automatic differentiation of mathematical functions. The first method is based on Faà di Bruno's formula that generalizes the chain rule. The second one makes use of the second order differential equation they satisfy. Both methods are exemplified with the aforementioned functions.

  15. Differentiation of Enhancing Glioma and Primary Central Nervous System Lymphoma by Texture-Based Machine Learning.

    Science.gov (United States)

    Alcaide-Leon, P; Dufort, P; Geraldo, A F; Alshafai, L; Maralani, P J; Spears, J; Bharatha, A

    2017-06-01

    Accurate preoperative differentiation of primary central nervous system lymphoma and enhancing glioma is essential to avoid unnecessary neurosurgical resection in patients with primary central nervous system lymphoma. The purpose of the study was to evaluate the diagnostic performance of a machine-learning algorithm by using texture analysis of contrast-enhanced T1-weighted images for differentiation of primary central nervous system lymphoma and enhancing glioma. Seventy-one adult patients with enhancing gliomas and 35 adult patients with primary central nervous system lymphomas were included. The tumors were manually contoured on contrast-enhanced T1WI, and the resulting volumes of interest were mined for textural features and subjected to a support vector machine-based machine-learning protocol. Three readers classified the tumors independently on contrast-enhanced T1WI. Areas under the receiver operating characteristic curves were estimated for each reader and for the support vector machine classifier. A noninferiority test for diagnostic accuracy based on paired areas under the receiver operating characteristic curve was performed with a noninferiority margin of 0.15. The mean areas under the receiver operating characteristic curve were 0.877 (95% CI, 0.798-0.955) for the support vector machine classifier; 0.878 (95% CI, 0.807-0.949) for reader 1; 0.899 (95% CI, 0.833-0.966) for reader 2; and 0.845 (95% CI, 0.757-0.933) for reader 3. The mean area under the receiver operating characteristic curve of the support vector machine classifier was significantly noninferior to the mean area under the curve of reader 1 ( P = .021), reader 2 ( P = .035), and reader 3 ( P = .007). Support vector machine classification based on textural features of contrast-enhanced T1WI is noninferior to expert human evaluation in the differentiation of primary central nervous system lymphoma and enhancing glioma. © 2017 by American Journal of Neuroradiology.

  16. Three Steps Lead to Differentiation

    Science.gov (United States)

    Bowgren, Linda; Sever, Kathryn

    2010-01-01

    Much has been written about the value, need, and complexity of differentiating learning within every classroom based on student readiness, motivation and interest, apparent skills, learning preferences or styles, and identified cognitive needs. Teachers are encouraged to look at differentiation for students not as a formula for teaching, but…

  17. Au Contraire: Differentiation Requires HOPE

    Science.gov (United States)

    Delisle, James R.

    2002-01-01

    Everybody is doing it: differentiating curriculum to make it deeper, broader, parallel, and more complex. No longer the private property of gifted specialists, differentiation is now a democratic pursuit of classroom teachers, curriculum specialists, and anyone else who subscribes to "Educational Leadership." In an era of competency-based tests…

  18. Complex Conjugated certificateless-based signcryption with differential integrated factor for secured message communication in mobile network.

    Directory of Open Access Journals (Sweden)

    Sumithra Alagarsamy

    Full Text Available Certificateless-based signcryption overcomes inherent shortcomings in traditional Public Key Infrastructure (PKI and Key Escrow problem. It imparts efficient methods to design PKIs with public verifiability and cipher text authenticity with minimum dependency. As a classic primitive in public key cryptography, signcryption performs validity of cipher text without decryption by combining authentication, confidentiality, public verifiability and cipher text authenticity much more efficiently than the traditional approach. In this paper, we first define a security model for certificateless-based signcryption called, Complex Conjugate Differential Integrated Factor (CC-DIF scheme by introducing complex conjugates through introduction of the security parameter and improving secured message distribution rate. However, both partial private key and secret value changes with respect to time. To overcome this weakness, a new certificateless-based signcryption scheme is proposed by setting the private key through Differential (Diff Equation using an Integration Factor (DiffEIF, minimizing computational cost and communication overhead. The scheme is therefore said to be proven secure (i.e. improving the secured message distributing rate against certificateless access control and signcryption-based scheme. In addition, compared with the three other existing schemes, the CC-DIF scheme has the least computational cost and communication overhead for secured message communication in mobile network.

  19. Complex Conjugated certificateless-based signcryption with differential integrated factor for secured message communication in mobile network.

    Science.gov (United States)

    Alagarsamy, Sumithra; Rajagopalan, S P

    2017-01-01

    Certificateless-based signcryption overcomes inherent shortcomings in traditional Public Key Infrastructure (PKI) and Key Escrow problem. It imparts efficient methods to design PKIs with public verifiability and cipher text authenticity with minimum dependency. As a classic primitive in public key cryptography, signcryption performs validity of cipher text without decryption by combining authentication, confidentiality, public verifiability and cipher text authenticity much more efficiently than the traditional approach. In this paper, we first define a security model for certificateless-based signcryption called, Complex Conjugate Differential Integrated Factor (CC-DIF) scheme by introducing complex conjugates through introduction of the security parameter and improving secured message distribution rate. However, both partial private key and secret value changes with respect to time. To overcome this weakness, a new certificateless-based signcryption scheme is proposed by setting the private key through Differential (Diff) Equation using an Integration Factor (DiffEIF), minimizing computational cost and communication overhead. The scheme is therefore said to be proven secure (i.e. improving the secured message distributing rate) against certificateless access control and signcryption-based scheme. In addition, compared with the three other existing schemes, the CC-DIF scheme has the least computational cost and communication overhead for secured message communication in mobile network.

  20. Design Optimization of Mechanical Components Using an Enhanced Teaching-Learning Based Optimization Algorithm with Differential Operator

    Directory of Open Access Journals (Sweden)

    B. Thamaraikannan

    2014-01-01

    Full Text Available This paper studies in detail the background and implementation of a teaching-learning based optimization (TLBO algorithm with differential operator for optimization task of a few mechanical components, which are essential for most of the mechanical engineering applications. Like most of the other heuristic techniques, TLBO is also a population-based method and uses a population of solutions to proceed to the global solution. A differential operator is incorporated into the TLBO for effective search of better solutions. To validate the effectiveness of the proposed method, three typical optimization problems are considered in this research: firstly, to optimize the weight in a belt-pulley drive, secondly, to optimize the volume in a closed coil helical spring, and finally to optimize the weight in a hollow shaft. have been demonstrated. Simulation result on the optimization (mechanical components problems reveals the ability of the proposed methodology to find better optimal solutions compared to other optimization algorithms.

  1. Optimasi Peletakan Base Transceiver Station Di Kabupaten Mojokerto Menggunakan Algoritma Differential Evolution

    Directory of Open Access Journals (Sweden)

    Ahadi Arif Nugraha

    2015-03-01

    Full Text Available Salah satu aspek penting dalam perencanaan infrastruktur jaringan seluler adalah Base Transceiver Station (BTS yang merupakan sebuah pemancar dan penerima sinyal telephone seluler. Di satu sisi, peningkatan jumlah menara memang akan mendukung tercapainya pemenuhan kebutuhan masyarakat terhadap layanan telekomunikasi. Namun di sisi lain, penempatan menara yang  tanpa perencanaan serta koordinasi yang tepat akan menimbulkan jumlah menara yang berlebih sehingga dapat mengganggu estetika lingkungan, tata ruang suatu wilayah, dan radiasi gelombang radio yang tidak terkontrol sehingga sangat mengganggu. Berdasarkan permasalahan diatas, maka dapat diselesaikan dengan cara menyusun suatu master plan yang lengkap dan rinci tentang penataan lokasi menara di Kabupaten Mojokerto untuk lima tahun mendatang. Penataan lokasi menara dilakukan dengan menggunakan algoritma Differential Evolution (DE untuk menemukan solusi penataan menara yang baik berdasarkan luas cakupan area sel yang dihasilkan, kemudian menggunakan software MapInfo sebagai media visualisasi peta lokasi penempatan menara telekomunikasi. Dalam perancangan menara BTS tahun 2019, Kabupaten Mojokerto membutuhkan 106 menara BTS 2G dan 36 menara BTS 3G. Penempatan menara BTS 2G dan 3G menggunakan algoritma differential evolution mampu mengoptimalkan 2,94% dari luas wilayah Kabupaten Mojokerto

  2. Parameter Estimation for Partial Differential Equations by Collage-Based Numerical Approximation

    Directory of Open Access Journals (Sweden)

    Xiaoyan Deng

    2009-01-01

    into a minimization problem of a function of several variables after the partial differential equation is approximated by a differential dynamical system. Then numerical schemes for solving this minimization problem are proposed, including grid approximation and ant colony optimization. The proposed schemes are applied to a parameter estimation problem for the Belousov-Zhabotinskii equation, and the results show that the proposed approximation method is efficient for both linear and nonlinear partial differential equations with respect to unknown parameters. At worst, the presented method provides an excellent starting point for traditional inversion methods that must first select a good starting point.

  3. A SLAM based on auxiliary marginalised particle filter and differential evolution

    Science.gov (United States)

    Havangi, R.; Nekoui, M. A.; Teshnehlab, M.; Taghirad, H. D.

    2014-09-01

    FastSLAM is a framework for simultaneous localisation and mapping (SLAM) using a Rao-Blackwellised particle filter. In FastSLAM, particle filter is used for the robot pose (position and orientation) estimation, and parametric filter (i.e. EKF and UKF) is used for the feature location's estimation. However, in the long term, FastSLAM is an inconsistent algorithm. In this paper, a new approach to SLAM based on hybrid auxiliary marginalised particle filter and differential evolution (DE) is proposed. In the proposed algorithm, the robot pose is estimated based on auxiliary marginal particle filter that operates directly on the marginal distribution, and hence avoids performing importance sampling on a space of growing dimension. In addition, static map is considered as a set of parameters that are learned using DE. Compared to other algorithms, the proposed algorithm can improve consistency for longer time periods and also, improve the estimation accuracy. Simulations and experimental results indicate that the proposed algorithm is effective.

  4. The reliability of differentiating neurogenic claudication from vascular claudication based on symptomatic presentation.

    Science.gov (United States)

    Nadeau, Mélissa; Rosas-Arellano, M Patricia; Gurr, Kevin R; Bailey, Stewart I; Taylor, David C; Grewal, Ruby; Lawlor, D Kirk; Bailey, Chris S

    2013-12-01

    Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.

  5. An Operational Matrix Technique for Solving Variable Order Fractional Differential-Integral Equation Based on the Second Kind of Chebyshev Polynomials

    Directory of Open Access Journals (Sweden)

    Jianping Liu

    2016-01-01

    Full Text Available An operational matrix technique is proposed to solve variable order fractional differential-integral equation based on the second kind of Chebyshev polynomials in this paper. The differential operational matrix and integral operational matrix are derived based on the second kind of Chebyshev polynomials. Using two types of operational matrixes, the original equation is transformed into the arithmetic product of several dependent matrixes, which can be viewed as an algebraic system after adopting the collocation points. Further, numerical solution of original equation is obtained by solving the algebraic system. Finally, several examples show that the numerical algorithm is computationally efficient.

  6. Neurosphere based differentiation of human iPSC improves astrocyte differentiation

    DEFF Research Database (Denmark)

    Zhou, Shuling; Szczesna, Karolina; Ochalek, Anna

    2016-01-01

    Neural progenitor cells (NPCs) derived from human induced pluripotent stem cells (iPSCs) are traditionally maintained and proliferated utilizing two-dimensional (2D) adherent monolayer culture systems. However, NPCs cultured using this system hardly reflect the intrinsic spatial development...... of brain tissue. In this study, we determined that culturing iPSC-derived NPCs as three-dimensional (3D) floating neurospheres resulted in increased expression of the neural progenitor cell (NPC) markers, PAX6 and NESTIN. Expansion of NPCs in 3D culture methods also resulted in a more homogenous PAX6...... expression when compared to 2D culture methods. Furthermore, the 3D propagation method for NPCs resulted in a significant higher expression of the astrocyte markers  GFAP and aquaporin 4 (AQP4) in the differentiated cells. Thus, our 3D propagation method could constitute a useful tool to promote NPC...

  7. Magneto-motive detection of tissue-based macrophages by differential phase optical coherence tomography.

    Science.gov (United States)

    Oh, Junghwan; Feldman, Marc D; Kim, Jihoon; Kang, Hyun Wook; Sanghi, Pramod; Milner, Thomas E

    2007-03-01

    A novel method to detect tissue-based macrophages using a combination of superparamagnetic iron oxide (SPIO) nanoparticles and differential phase optical coherence tomography (DP-OCT) with an external oscillating magnetic field is reported. Magnetic force acting on iron-laden tissue-based macrophages was varied by applying a sinusoidal current to a solenoid containing a conical iron core that substantially focused and increased magnetic flux density. Nanoparticle motion was detected with DP-OCT, which can detect tissue movement with nanometer resolution. Frequency response of iron-laden tissue movement was twice the modulation frequency since the magnetic force is proportional to the product of magnetic flux density and gradient. Results of our experiments indicate that DP-OCT can be used to identify tissue-based macrophage when excited by an external focused oscillating magnetic field. (c) 2007 Wiley-Liss, Inc

  8. Free Vibration Analysis of Fiber Metal Laminate Annular Plate by State-Space Based Differential Quadrature Method

    Directory of Open Access Journals (Sweden)

    G. H. Rahimi

    2014-01-01

    Full Text Available A three-dimensional elasticity theory by means of a state-space based differential quadrature method is presented for free vibration analysis of fiber metal laminate annular plate. The kinds of composite material and metal layers are considered to be S2-glass and aluminum, respectively. A semianalytical approach which uses state-space in the thickness and differential quadrature in the radial direction is implemented for evaluating the nondimensional natural frequencies of the annular plates. The influences of changes in boundary condition, plate thickness, and lay-up direction on the natural frequencies are studied. A comparison is also made with the numerical results reported by ABAQUS software which shows an excellent agreement.

  9. An Energy Efficient Hydraulic Winch Drive Concept Based on a Speed-variable Switched Differential Pump

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben O.; Pedersen, Henrik Clemmensen

    2017-01-01

    controls. Such solutions are typically constituted by many and rather expensive components, and are furthermore often suffering from low frequency dynamics. In this paper an alternative solution is proposed for winch drive operation, which is based on the so-called speed-variable switched differential pump......, originally designed for direct drive of hydraulic differential cylinders. This concept utilizes three pumps, driven by a single electric servo drive. The concept is redesigned for usage in winch drives, driven by flow symmetric hydraulic motors and single directional loads as commonly seen in e.g. active...... heave compensation applications. A general drive configuration approach is presented, along with a proper control strategy and design. The resulting concept is evaluated when applied for active heave compensation. Results demonstrate control performance on level with conventional valve solutions...

  10. A Bifactor Multidimensional Item Response Theory Model for Differential Item Functioning Analysis on Testlet-Based Items

    Science.gov (United States)

    Fukuhara, Hirotaka; Kamata, Akihito

    2011-01-01

    A differential item functioning (DIF) detection method for testlet-based data was proposed and evaluated in this study. The proposed DIF model is an extension of a bifactor multidimensional item response theory (MIRT) model for testlets. Unlike traditional item response theory (IRT) DIF models, the proposed model takes testlet effects into…

  11. Construction of Interval Wavelet Based on Restricted Variational Principle and Its Application for Solving Differential Equations

    OpenAIRE

    Mei, Shu-Li; Lv, Hong-Liang; Ma, Qin

    2008-01-01

    Based on restricted variational principle, a novel method for interval wavelet construction is proposed. For the excellent local property of quasi-Shannon wavelet, its interval wavelet is constructed, and then applied to solve ordinary differential equations. Parameter choices for the interval wavelet method are discussed and its numerical performance is demonstrated.

  12. Cloud-based solution to identify statistically significant MS peaks differentiating sample categories.

    Science.gov (United States)

    Ji, Jun; Ling, Jeffrey; Jiang, Helen; Wen, Qiaojun; Whitin, John C; Tian, Lu; Cohen, Harvey J; Ling, Xuefeng B

    2013-03-23

    Mass spectrometry (MS) has evolved to become the primary high throughput tool for proteomics based biomarker discovery. Until now, multiple challenges in protein MS data analysis remain: large-scale and complex data set management; MS peak identification, indexing; and high dimensional peak differential analysis with the concurrent statistical tests based false discovery rate (FDR). "Turnkey" solutions are needed for biomarker investigations to rapidly process MS data sets to identify statistically significant peaks for subsequent validation. Here we present an efficient and effective solution, which provides experimental biologists easy access to "cloud" computing capabilities to analyze MS data. The web portal can be accessed at http://transmed.stanford.edu/ssa/. Presented web application supplies large scale MS data online uploading and analysis with a simple user interface. This bioinformatic tool will facilitate the discovery of the potential protein biomarkers using MS.

  13. Spectrum interrogation of fiber acoustic sensor based on self-fitting and differential method.

    Science.gov (United States)

    Fu, Xin; Lu, Ping; Ni, Wenjun; Liao, Hao; Wang, Shun; Liu, Deming; Zhang, Jiangshan

    2017-02-20

    In this article, we propose an interrogation method of fiber acoustic sensor to recover the time-domain signal from the sensor spectrum. The optical spectrum of the sensor will show a ripple waveform when responding to acoustic signal due to the scanning process in a certain wavelength range. The reason behind this phenomenon is the dynamic variation of the sensor spectrum while the intensity of different wavelength is acquired at different time in a scanning period. The frequency components can be extracted from the ripple spectrum assisted by the wavelength scanning speed. The signal is able to be recovered by differential between the ripple spectrum and its self-fitted curve. The differential process can eliminate the interference caused by environmental perturbations such as temperature or refractive index (RI), etc. The proposed method is appropriate for fiber acoustic sensors based on gratings or interferometers. A long period grating (LPG) is adopted as an acoustic sensor head to prove the feasibility of the interrogation method in experiment. The ability to compensate the environmental fluctuations is also demonstrated.

  14. Linking Diversity and Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Rolf Gregorius

    2010-03-01

    Full Text Available Generally speaking, the term differentiation refers to differences between collections for the distribution of specified traits of their members, while diversity deals with (effective numbers of trait states (types. Counting numbers of types implies discrete traits such as alleles and genotypes in population genetics or species and taxa in ecology. Comparisons between the concepts of differentiation and diversity therefore primarily refer to discrete traits. Diversity is related to differentiation through the idea that the total diversity of a subdivided collection should be composed of the diversity within the subcollections and a complement called “diversity between subcollections”. The idea goes back to the perception that the mixing of differentiated collections increases diversity. Several existing concepts of “diversity between subcollections” are based on this idea. Among them, β-diversity and fixation (inadvertently called differentiation are the most prominent in ecology and in population genetics, respectively. The pertaining measures are shown to quantify the effect of differentiation in terms of diversity components, though from a dual perspective: the classical perspective of differentiation between collections for their type compositions, and the reverse perspective of differentiation between types for their collection affiliations. A series of measures of diversity-oriented differentiation is presented that consider this dual perspective at two levels of diversity partitioning: the overall type or subcollection diversity and the joint type-subcollection diversity. It turns out that, in contrast with common notions, the measures of fixation (such as FST or GST refer to the perspective of type rather than subcollection differentiation. This unexpected observation strongly suggests that the popular interpretations of fixation measures must be reconsidered.

  15. ON DIFFERENTIAL EQUATIONS, INTEGRABLE SYSTEMS, AND GEOMETRY

    OpenAIRE

    Enrique Gonzalo Reyes Garcia

    2004-01-01

    ON DIFFERENTIAL EQUATIONS, INTEGRABLE SYSTEMS, AND GEOMETRY Equations in partial derivatives appeared in the 18th century as essential tools for the analytic study of physical models and, later, they proved to be fundamental for the progress of mathematics. For example, fundamental results of modern differential geometry are based on deep theorems on differential equations. Reciprocally, it is possible to study differential equations through geometrical means just like it was done by o...

  16. QoS Differential Scheduling in Cognitive-Radio-Based Smart Grid Networks: An Adaptive Dynamic Programming Approach.

    Science.gov (United States)

    Yu, Rong; Zhong, Weifeng; Xie, Shengli; Zhang, Yan; Zhang, Yun

    2016-02-01

    As the next-generation power grid, smart grid will be integrated with a variety of novel communication technologies to support the explosive data traffic and the diverse requirements of quality of service (QoS). Cognitive radio (CR), which has the favorable ability to improve the spectrum utilization, provides an efficient and reliable solution for smart grid communications networks. In this paper, we study the QoS differential scheduling problem in the CR-based smart grid communications networks. The scheduler is responsible for managing the spectrum resources and arranging the data transmissions of smart grid users (SGUs). To guarantee the differential QoS, the SGUs are assigned to have different priorities according to their roles and their current situations in the smart grid. Based on the QoS-aware priority policy, the scheduler adjusts the channels allocation to minimize the transmission delay of SGUs. The entire transmission scheduling problem is formulated as a semi-Markov decision process and solved by the methodology of adaptive dynamic programming. A heuristic dynamic programming (HDP) architecture is established for the scheduling problem. By the online network training, the HDP can learn from the activities of primary users and SGUs, and adjust the scheduling decision to achieve the purpose of transmission delay minimization. Simulation results illustrate that the proposed priority policy ensures the low transmission delay of high priority SGUs. In addition, the emergency data transmission delay is also reduced to a significantly low level, guaranteeing the differential QoS in smart grid.

  17. A novel approach to select differential pathways associated with hypertrophic cardiomyopathy based on gene co‑expression analysis.

    Science.gov (United States)

    Chen, Xiao-Min; Feng, Ming-Jun; Shen, Cai-Jie; He, Bin; Du, Xian-Feng; Yu, Yi-Bo; Liu, Jing; Chu, Hui-Min

    2017-07-01

    The present study was designed to develop a novel method for identifying significant pathways associated with human hypertrophic cardiomyopathy (HCM), based on gene co‑expression analysis. The microarray dataset associated with HCM (E‑GEOD‑36961) was obtained from the European Molecular Biology Laboratory‑European Bioinformatics Institute database. Informative pathways were selected based on the Reactome pathway database and screening treatments. An empirical Bayes method was utilized to construct co‑expression networks for informative pathways, and a weight value was assigned to each pathway. Differential pathways were extracted based on weight threshold, which was calculated using a random model. In order to assess whether the co‑expression method was feasible, it was compared with traditional pathway enrichment analysis of differentially expressed genes, which were identified using the significance analysis of microarrays package. A total of 1,074 informative pathways were screened out for subsequent investigations and their weight values were also obtained. According to the threshold of weight value of 0.01057, 447 differential pathways, including folding of actin by chaperonin containing T‑complex protein 1 (CCT)/T‑complex protein 1 ring complex (TRiC), purine ribonucleoside monophosphate biosynthesis and ubiquinol biosynthesis, were obtained. Compared with traditional pathway enrichment analysis, the number of pathways obtained from the co‑expression approach was increased. The results of the present study demonstrated that this method may be useful to predict marker pathways for HCM. The pathways of folding of actin by CCT/TRiC and purine ribonucleoside monophosphate biosynthesis may provide evidence of the underlying molecular mechanisms of HCM, and offer novel therapeutic directions for HCM.

  18. Differential barometric-based positioning technique for indoor elevation measurement in IoT medical applications.

    Science.gov (United States)

    Wang, Hua; Wen, Yingyou; Zhao, Dazhe

    2017-07-20

    Medical applications have begun to benefit from Internet of Things (IoT) technology through the introduction of wearable devices. Several medical applications require accurate patient location as various changes affect pressure parameters inside the body. This study aims to develop a system to measure indoor altitude for IoT medical applications. We propose a differential barometric-based positioning system to estimate the altitude between a reference sensor and a localizing sensor connected to the human body. The differential barometric altimetry model is introduced to estimate indoor elevations and eliminate environmental artifacts. In addition, a Gaussian filter processing is adopted to remove noise from the elevation measurements. The proposed system is then investigated through extensive experiments, using various evaluation criteria. The results indicate that the proposed system yielded good accuracy with reduced implementation complexity and fewer costs. The proposed system is resilient compared to other indoor localization approaches, even when numerous environmental artifacts in indoor environments are present.

  19. Osteoclast differentiation inhibitors: a patent review (2008 - 2012).

    Science.gov (United States)

    Kim, Seong Hwan; Moon, Seong-Hee

    2013-12-01

    Mononuclear macrophage/monocyte-lineage hematopoietic precursors differentiate into multinucleated osteoclasts. Abnormally increased numbers and/or overactivation of osteoclasts can lead to bone loss. Therefore, pharmaceutical inhibition of osteoclast differentiation is one therapeutic strategy for mitigating the occurrence of bone loss-associated disorders and related fractures. This review surveys the patents and patent applications from 2008 to 2012 that are related to inventions of therapeutics and/or methods for inhibiting osteoclast differentiation. Over the past 20 years, the identification and validation of signaling molecules involved in osteoclast differentiation has led to a better understanding of the molecular mechanism, and to the development of new therapeutic agents for treating bone loss-associated disorders. Since 2008, 34 WO patents or patent applications have been filed that relate to inventions of therapeutics and/or methods for chemical-based, natural product-based, or biological-based inhibitors of osteoclast differentiation. Here, analysis of these patents and patent applications is presented, and summarize the disclosed osteoclast differentiation-inhibiting target molecules. This report can support further advances in the development of anti-osteoclastogenic therapeutics for bone loss-associated disorders, including osteoporosis, rheumatoid arthritis, Paget's disease, periodontal disease, osteosarcoma, and cancer bone metastasis.

  20. Filters in topology optimization based on Helmholtz‐type differential equations

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Sigmund, Ole

    2011-01-01

    The aim of this paper is to apply a Helmholtz‐type partial differential equation as an alternative to standard density filtering in topology optimization problems. Previously, this approach has been successfully applied as a sensitivity filter. The usual filtering techniques in topology...... from the neighbor subdomains is an expensive operation. The proposed filter technique requires only mesh information necessary for the finite element discretization of the problem. The main idea is to define the filtered variable implicitly as a solution of a Helmholtz‐type differential equation...

  1. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATEMATICA based packages for differential reduction of generalized hypergeometric functions. FD and FS Horn-type hypergeometric functions of three variables

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Moch, Sven-Olaf; Hamburg Univ.

    2013-12-01

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: the first one, FdFunction, for manipulations with Appell hypergeometric functions F D of r variables; and the second one, FsFunction, for manipulations with Lauricella-Saran hypergeometric functions F S of three variables. Both functions are related with one-loop Feynman diagrams.

  2. Statistical method evaluation for differentially methylated CpGs in base resolution next-generation DNA sequencing data.

    Science.gov (United States)

    Zhang, Yun; Baheti, Saurabh; Sun, Zhifu

    2018-05-01

    High-throughput bisulfite methylation sequencing such as reduced representation bisulfite sequencing (RRBS), Agilent SureSelect Human Methyl-Seq (Methyl-seq) or whole-genome bisulfite sequencing is commonly used for base resolution methylome research. These data are represented either by the ratio of methylated cytosine versus total coverage at a CpG site or numbers of methylated and unmethylated cytosines. Multiple statistical methods can be used to detect differentially methylated CpGs (DMCs) between conditions, and these methods are often the base for the next step of differentially methylated region identification. The ratio data have a flexibility of fitting to many linear models, but the raw count data take consideration of coverage information. There is an array of options in each datatype for DMC detection; however, it is not clear which is an optimal statistical method. In this study, we systematically evaluated four statistic methods on methylation ratio data and four methods on count-based data and compared their performances with regard to type I error control, sensitivity and specificity of DMC detection and computational resource demands using real RRBS data along with simulation. Our results show that the ratio-based tests are generally more conservative (less sensitive) than the count-based tests. However, some count-based methods have high false-positive rates and should be avoided. The beta-binomial model gives a good balance between sensitivity and specificity and is preferred method. Selection of methods in different settings, signal versus noise and sample size estimation are also discussed.

  3. Numerical simulation for Jeffery-Hamel flow and heat transfer of micropolar fluid based on differential evolution algorithm

    Science.gov (United States)

    Ara, Asmat; Khan, Najeeb Alam; Naz, Farah; Raja, Muhammad Asif Zahoor; Rubbab, Qammar

    2018-01-01

    This article explores the Jeffery-Hamel flow of an incompressible non-Newtonian fluid inside non-parallel walls and observes the influence of heat transfer in the flow field. The fluid is considered to be micropolar fluid that flows in a convergent/divergent channel. The governing nonlinear partial differential equations (PDEs) are converted to nonlinear coupled ordinary differential equations (ODEs) with the help of a suitable similarity transformation. The resulting nonlinear analysis is determined analytically with the utilization of the Taylor optimization method based on differential evolution (DE) algorithm. In order to understand the flow field, the effects of pertinent parameters such as the coupling parameter, spin gradient viscosity parameter and the Reynolds number have been examined on velocity and temperature profiles. It concedes that the good results can be attained by an implementation of the proposed method. Ultimately, the accuracy of the method is confirmed by comparing the present results with the results obtained by Runge-Kutta method.

  4. Numerical simulation for Jeffery-Hamel flow and heat transfer of micropolar fluid based on differential evolution algorithm

    Directory of Open Access Journals (Sweden)

    Asmat Ara

    2018-01-01

    Full Text Available This article explores the Jeffery-Hamel flow of an incompressible non-Newtonian fluid inside non-parallel walls and observes the influence of heat transfer in the flow field. The fluid is considered to be micropolar fluid that flows in a convergent/divergent channel. The governing nonlinear partial differential equations (PDEs are converted to nonlinear coupled ordinary differential equations (ODEs with the help of a suitable similarity transformation. The resulting nonlinear analysis is determined analytically with the utilization of the Taylor optimization method based on differential evolution (DE algorithm. In order to understand the flow field, the effects of pertinent parameters such as the coupling parameter, spin gradient viscosity parameter and the Reynolds number have been examined on velocity and temperature profiles. It concedes that the good results can be attained by an implementation of the proposed method. Ultimately, the accuracy of the method is confirmed by comparing the present results with the results obtained by Runge-Kutta method.

  5. Subtype differentiation of renal tumors using voxel-based histogram analysis of intravoxel incoherent motion parameters.

    Science.gov (United States)

    Gaing, Byron; Sigmund, Eric E; Huang, William C; Babb, James S; Parikh, Nainesh S; Stoffel, David; Chandarana, Hersh

    2015-03-01

    The aim of this study was to determine if voxel-based histogram analysis of intravoxel incoherent motion imaging (IVIM) parameters can differentiate various subtypes of renal tumors, including benign and malignant lesions. A total of 44 patients with renal tumors who underwent surgery and had histopathology available were included in this Health Insurance Portability and Accountability Act-compliant, institutional review board-approved, single-institution prospective study. In addition to routine renal magnetic resonance imaging examination performed on a 1.5-T system, all patients were imaged with axial diffusion-weighted imaging using 8 b values (range, 0-800 s/mm). A biexponential model was fitted to the diffusion signal data using a segmented algorithm to extract the IVIM parameters perfusion fraction (fp), tissue diffusivity (Dt), and pseudodiffusivity (Dp) for each voxel. Mean and histogram measures of heterogeneity (standard deviation, skewness, and kurtosis) of IVIM parameters were correlated with pathology results of tumor subtype using unequal variance t tests to compare subtypes in terms of each measure. Correction for multiple comparisons was accomplished using the Tukey honestly significant difference procedure. A total of 44 renal tumors including 23 clear cell (ccRCC), 4 papillary (pRCC), 5 chromophobe, and 5 cystic renal cell carcinomas, as well as benign lesions, 4 oncocytomas (Onc) and 3 angiomyolipomas (AMLs), were included in our analysis. Mean IVIM parameters fp and Dt differentiated 8 of 15 pairs of renal tumors. Histogram analysis of IVIM parameters differentiated 9 of 15 subtype pairs. One subtype pair (ccRCC vs pRCC) was differentiated by mean analysis but not by histogram analysis. However, 2 other subtype pairs (AML vs Onc and ccRCC vs Onc) were differentiated by histogram distribution parameters exclusively. The standard deviation of Dt [σ(Dt)] differentiated ccRCC (0.362 ± 0.136 × 10 mm/s) from AML (0.199 ± 0.043 × 10 mm/s) (P = 0

  6. A resampling-based meta-analysis for detection of differential gene expression in breast cancer

    International Nuclear Information System (INIS)

    Gur-Dedeoglu, Bala; Konu, Ozlen; Kir, Serkan; Ozturk, Ahmet Rasit; Bozkurt, Betul; Ergul, Gulusan; Yulug, Isik G

    2008-01-01

    Accuracy in the diagnosis of breast cancer and classification of cancer subtypes has improved over the years with the development of well-established immunohistopathological criteria. More recently, diagnostic gene-sets at the mRNA expression level have been tested as better predictors of disease state. However, breast cancer is heterogeneous in nature; thus extraction of differentially expressed gene-sets that stably distinguish normal tissue from various pathologies poses challenges. Meta-analysis of high-throughput expression data using a collection of statistical methodologies leads to the identification of robust tumor gene expression signatures. A resampling-based meta-analysis strategy, which involves the use of resampling and application of distribution statistics in combination to assess the degree of significance in differential expression between sample classes, was developed. Two independent microarray datasets that contain normal breast, invasive ductal carcinoma (IDC), and invasive lobular carcinoma (ILC) samples were used for the meta-analysis. Expression of the genes, selected from the gene list for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes were tested on 10 independent primary IDC samples and matched non-tumor controls by real-time qRT-PCR. Other existing breast cancer microarray datasets were used in support of the resampling-based meta-analysis. The two independent microarray studies were found to be comparable, although differing in their experimental methodologies (Pearson correlation coefficient, R = 0.9389 and R = 0.8465 for ductal and lobular samples, respectively). The resampling-based meta-analysis has led to the identification of a highly stable set of genes for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes. The expression results of the selected genes obtained through real-time qRT-PCR supported the meta-analysis results. The

  7. A resampling-based meta-analysis for detection of differential gene expression in breast cancer

    Directory of Open Access Journals (Sweden)

    Ergul Gulusan

    2008-12-01

    Full Text Available Abstract Background Accuracy in the diagnosis of breast cancer and classification of cancer subtypes has improved over the years with the development of well-established immunohistopathological criteria. More recently, diagnostic gene-sets at the mRNA expression level have been tested as better predictors of disease state. However, breast cancer is heterogeneous in nature; thus extraction of differentially expressed gene-sets that stably distinguish normal tissue from various pathologies poses challenges. Meta-analysis of high-throughput expression data using a collection of statistical methodologies leads to the identification of robust tumor gene expression signatures. Methods A resampling-based meta-analysis strategy, which involves the use of resampling and application of distribution statistics in combination to assess the degree of significance in differential expression between sample classes, was developed. Two independent microarray datasets that contain normal breast, invasive ductal carcinoma (IDC, and invasive lobular carcinoma (ILC samples were used for the meta-analysis. Expression of the genes, selected from the gene list for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes were tested on 10 independent primary IDC samples and matched non-tumor controls by real-time qRT-PCR. Other existing breast cancer microarray datasets were used in support of the resampling-based meta-analysis. Results The two independent microarray studies were found to be comparable, although differing in their experimental methodologies (Pearson correlation coefficient, R = 0.9389 and R = 0.8465 for ductal and lobular samples, respectively. The resampling-based meta-analysis has led to the identification of a highly stable set of genes for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes. The expression results of the selected genes obtained through real

  8. On matrix fractional differential equations

    Directory of Open Access Journals (Sweden)

    Adem Kılıçman

    2017-01-01

    Full Text Available The aim of this article is to study the matrix fractional differential equations and to find the exact solution for system of matrix fractional differential equations in terms of Riemann–Liouville using Laplace transform method and convolution product to the Riemann–Liouville fractional of matrices. Also, we show the theorem of non-homogeneous matrix fractional partial differential equation with some illustrative examples to demonstrate the effectiveness of the new methodology. The main objective of this article is to discuss the Laplace transform method based on operational matrices of fractional derivatives for solving several kinds of linear fractional differential equations. Moreover, we present the operational matrices of fractional derivatives with Laplace transform in many applications of various engineering systems as control system. We present the analytical technique for solving fractional-order, multi-term fractional differential equation. In other words, we propose an efficient algorithm for solving fractional matrix equation.

  9. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATHEMATICA based packages for differential reduction of generalized hypergeometric functions pFp-1, F1, F2, F3, F4

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Kniehl, Bernd A.

    2013-05-01

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions p+1 F p , and the second one, AppellF1F4, for manipulations with Appell hypergeometric functions F 1 , F 2 , F 3 , F 4 of two variables.

  10. Resolving glass transition in Te-based phase-change materials by modulated differential scanning calorimetry

    Science.gov (United States)

    Chen, Yimin; Mu, Sen; Wang, Guoxiang; Shen, Xiang; Wang, Junqiang; Dai, Shixun; Xu, Tiefeng; Nie, Qiuhua; Wang, Rongping

    2017-10-01

    Glass transitions of Te-based phase-change materials (PCMs) were studied by modulated differential scanning calorimetry. It was found that both Ge2Sb2Te5 and GeTe are marginal glass formers with ΔT (= T x - T g) less than 2.1 °C when the heating rate is below 3 °C min-1. The fragilities of Ge2Sb2Te5 and GeTe can be estimated as 46.0 and 39.7, respectively, around the glass transition temperature, implying that a fragile-to-strong transition would be presented in such Te-based PCMs. The above results provide direct experimental evidence to support the investigation of crystallization kinetics in supercooled liquid PCMs.

  11. Iterative Splitting Methods for Differential Equations

    CERN Document Server

    Geiser, Juergen

    2011-01-01

    Iterative Splitting Methods for Differential Equations explains how to solve evolution equations via novel iterative-based splitting methods that efficiently use computational and memory resources. It focuses on systems of parabolic and hyperbolic equations, including convection-diffusion-reaction equations, heat equations, and wave equations. In the theoretical part of the book, the author discusses the main theorems and results of the stability and consistency analysis for ordinary differential equations. He then presents extensions of the iterative splitting methods to partial differential

  12. Study on TCM Syndrome Differentiation of Primary Liver Cancer Based on the Analysis of Latent Structural Model

    Directory of Open Access Journals (Sweden)

    Zhan Gu

    2015-01-01

    Full Text Available Primary liver cancer (PLC is one of the most common malignant tumors because of its high incidence and high mortality. Traditional Chinese medicine (TCM plays an active role in the treatment of PLC. As the most important part in the TCM system, syndrome differentiation based on the clinical manifestations from traditional four diagnostic methods has met great challenges and questions with the lack of statistical validation support. In this study, we provided evidences for TCM syndrome differentiation of PLC using the method of analysis of latent structural model from clinic data, thus providing basis for establishing TCM syndrome criteria. And also we obtain the common syndromes of PLC as well as their typical clinical manifestations, respectively.

  13. Study on TCM Syndrome Differentiation of Primary Liver Cancer Based on the Analysis of Latent Structural Model.

    Science.gov (United States)

    Gu, Zhan; Qi, Xiuzhong; Zhai, Xiaofeng; Lang, Qingbo; Lu, Jianying; Ma, Changping; Liu, Long; Yue, Xiaoqiang

    2015-01-01

    Primary liver cancer (PLC) is one of the most common malignant tumors because of its high incidence and high mortality. Traditional Chinese medicine (TCM) plays an active role in the treatment of PLC. As the most important part in the TCM system, syndrome differentiation based on the clinical manifestations from traditional four diagnostic methods has met great challenges and questions with the lack of statistical validation support. In this study, we provided evidences for TCM syndrome differentiation of PLC using the method of analysis of latent structural model from clinic data, thus providing basis for establishing TCM syndrome criteria. And also we obtain the common syndromes of PLC as well as their typical clinical manifestations, respectively.

  14. All-optical differential equation solver with constant-coefficient tunable based on a single microring resonator.

    Science.gov (United States)

    Yang, Ting; Dong, Jianji; Lu, Liangjun; Zhou, Linjie; Zheng, Aoling; Zhang, Xinliang; Chen, Jianping

    2014-07-04

    Photonic integrated circuits for photonic computing open up the possibility for the realization of ultrahigh-speed and ultra wide-band signal processing with compact size and low power consumption. Differential equations model and govern fundamental physical phenomena and engineering systems in virtually any field of science and engineering, such as temperature diffusion processes, physical problems of motion subject to acceleration inputs and frictional forces, and the response of different resistor-capacitor circuits, etc. In this study, we experimentally demonstrate a feasible integrated scheme to solve first-order linear ordinary differential equation with constant-coefficient tunable based on a single silicon microring resonator. Besides, we analyze the impact of the chirp and pulse-width of input signals on the computing deviation. This device can be compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may motivate the development of integrated photonic circuits for optical computing.

  15. Non-genetic heterogeneity, criticality and cell differentiation.

    Science.gov (United States)

    Pal, Mainak; Ghosh, Sayantari; Bose, Indrani

    2014-11-27

    The different cell types in a living organism acquire their identity through the process of cell differentiation in which multipotent progenitor cells differentiate into distinct cell types. Experimental evidence and analysis of large-scale microarray data establish the key role played by a two-gene motif in cell differentiation in a number of cell systems. The two genes express transcription factors which repress each other's expression and autoactivate their own production. A number of theoretical models have recently been proposed based on the two-gene motif to provide a physical understanding of how cell differentiation occurs. In this paper, we study a simple model of cell differentiation which assumes no cooperativity in the regulation of gene expression by the transcription factors. The latter repress each other's activity directly through DNA binding and indirectly through the formation of heterodimers. We specifically investigate how deterministic processes combined with stochasticity contribute in bringing about cell differentiation. The deterministic dynamics of our model give rise to a supercritical pitchfork bifurcation from an undifferentiated stable steady state to two differentiated stable steady states. The stochastic dynamics of our model are studied using the approaches based on the Langevin equations and the linear noise approximation. The simulation results provide a new physical understanding of recent experimental observations. We further propose experimental measurements of quantities like the variance and the lag-1 autocorrelation function in protein fluctuations as the early signatures of an approaching bifurcation point in the cell differentiation process.

  16. Preconditioners based on windowed Fourier frames applied to elliptic partial differential equations

    NARCIS (Netherlands)

    Bhowmik, S.K.; Stolk, C.C.

    2011-01-01

    We investigate the application of windowed Fourier frames to the numerical solution of partial differential equations, focussing on elliptic equations. The action of a partial differential operator (PDO) on a windowed plane wave is close to a multiplication, where the multiplication factor is given

  17. Automatic differentiation for gradient-based optimization of radiatively heated microelectronics manufacturing equipment

    Energy Technology Data Exchange (ETDEWEB)

    Moen, C.D.; Spence, P.A.; Meza, J.C.; Plantenga, T.D.

    1996-12-31

    Automatic differentiation is applied to the optimal design of microelectronic manufacturing equipment. The performance of nonlinear, least-squares optimization methods is compared between numerical and analytical gradient approaches. The optimization calculations are performed by running large finite-element codes in an object-oriented optimization environment. The Adifor automatic differentiation tool is used to generate analytic derivatives for the finite-element codes. The performance results support previous observations that automatic differentiation becomes beneficial as the number of optimization parameters increases. The increase in speed, relative to numerical differences, has a limited value and results are reported for two different analysis codes.

  18. The role of differentiation and standards-based grading in the science learning of struggling and advanced learners in a detracked high school honors biology classroom

    Science.gov (United States)

    MacDonald, Michelina Ruth Carter

    The accountability movement in education resulting from the passage of The No Child Left Behind Act of 2001 has brought to light the disparities that exist in student achievement in the United States which play out along racial and socioeconomic lines. Three educational practices hold promise for reducing this achievement gap: differentiated instruction, standards-based assessment, and elimination of academic tracking. The purpose of this practitioner research study was to examine the ways that differentiation and standards-based assessment can support struggling learners and challenge advanced learners in a detracked, honors biology classroom. To gain insight into the role that differentiation and standards-based assessment played in supporting struggling and advanced learners, I used practitioner research to examine the development and implementation of a differentiated, standards-based instructional unit around the conceptual topic of protein synthesis. I collected multiple data pieces for 10 students in the study: two advanced learners, four struggling learners, and four strong learners who struggled in biology. Data analyzed included formative, self-, and summative assessment results; student artifacts; informal and formal student interviews; and, a practitioner reflection journal chronicling critical incidents and actions taken during the development and implementation of this unit and notes from peer debriefing during and following the unit's implementation. As I analyzed the data collected, my four findings fell into two overarching categories related to student grouping. My first three findings reflect what I learned about homogeneous grouping: (1) Pre-assessment based on unit outcomes is not useful for determining groups for tiered instruction; (2) Decisions about differentiation and grouping for differentiation must be made in the act of teaching using formative assessment results; and, (3) Flexible grouping structures are effective for both struggling

  19. Differential privacy-based evaporative cooling feature selection and classification with relief-F and random forests.

    Science.gov (United States)

    Le, Trang T; Simmons, W Kyle; Misaki, Masaya; Bodurka, Jerzy; White, Bill C; Savitz, Jonathan; McKinney, Brett A

    2017-09-15

    Classification of individuals into disease or clinical categories from high-dimensional biological data with low prediction error is an important challenge of statistical learning in bioinformatics. Feature selection can improve classification accuracy but must be incorporated carefully into cross-validation to avoid overfitting. Recently, feature selection methods based on differential privacy, such as differentially private random forests and reusable holdout sets, have been proposed. However, for domains such as bioinformatics, where the number of features is much larger than the number of observations p≫n , these differential privacy methods are susceptible to overfitting. We introduce private Evaporative Cooling, a stochastic privacy-preserving machine learning algorithm that uses Relief-F for feature selection and random forest for privacy preserving classification that also prevents overfitting. We relate the privacy-preserving threshold mechanism to a thermodynamic Maxwell-Boltzmann distribution, where the temperature represents the privacy threshold. We use the thermal statistical physics concept of Evaporative Cooling of atomic gases to perform backward stepwise privacy-preserving feature selection. On simulated data with main effects and statistical interactions, we compare accuracies on holdout and validation sets for three privacy-preserving methods: the reusable holdout, reusable holdout with random forest, and private Evaporative Cooling, which uses Relief-F feature selection and random forest classification. In simulations where interactions exist between attributes, private Evaporative Cooling provides higher classification accuracy without overfitting based on an independent validation set. In simulations without interactions, thresholdout with random forest and private Evaporative Cooling give comparable accuracies. We also apply these privacy methods to human brain resting-state fMRI data from a study of major depressive disorder. Code

  20. Accelerating parameter identification of proton exchange membrane fuel cell model with ranking-based differential evolution

    International Nuclear Information System (INIS)

    Gong, Wenyin; Cai, Zhihua

    2013-01-01

    Parameter identification of PEM (proton exchange membrane) fuel cell model is a very active area of research. Generally, it can be treated as a numerical optimization problem with complex nonlinear and multi-variable features. DE (differential evolution), which has been successfully used in various fields, is a simple yet efficient evolutionary algorithm for global numerical optimization. In this paper, with the objective of accelerating the process of parameter identification of PEM fuel cell models and reducing the necessary computational efforts, we firstly present a generic and simple ranking-based mutation operator for the DE algorithm. Then, the ranking-based mutation operator is incorporated into five highly-competitive DE variants to solve the PEM fuel cell model parameter identification problems. The main contributions of this work are the proposed ranking-based DE variants and their application to the parameter identification problems of PEM fuel cell models. Experiments have been conducted by using both the simulated voltage–current data and the data obtained from the literature to validate the performance of our approach. The results indicate that the ranking-based DE methods provide better results with respect to the solution quality, the convergence rate, and the success rate compared with their corresponding original DE methods. In addition, the voltage–current characteristics obtained by our approach are in good agreement with the original voltage–current curves in all cases. - Highlights: • A simple and generic ranking-based mutation operator is presented in this paper. • Several DE (differential evolution) variants are used to solve the parameter identification of PEMFC (proton exchange membrane fuel cells) model. • Results show that our method accelerates the process of parameter identification. • The V–I characteristics are in very good agreement with experimental data

  1. effect of differentiated instructional strategies on students' retention

    African Journals Online (AJOL)

    PROF EKWUEME

    show that retention ability was significantly higher in the experimental group ... Differentiated instruction, Lecture , Cognitive Achievement ,Retention ability, Geometry. ... thinking. Based on this knowledge, differentiated instruction applies an ...

  2. Moving Object Tracking and Avoidance Algorithm for Differential Driving AGV Based on Laser Measurement Technology

    Directory of Open Access Journals (Sweden)

    Pandu Sandi Pratama

    2012-12-01

    Full Text Available This paper proposed an algorithm to track the obstacle position and avoid the moving objects for differential driving Automatic Guided Vehicles (AGV system in industrial environment. This algorithm has several abilities such as: to detect the moving objects, to predict the velocity and direction of moving objects, to predict the collision possibility and to plan the avoidance maneuver. For sensing the local environment and positioning, the laser measurement system LMS-151 and laser navigation system NAV-200 are applied. Based on the measurement results of the sensors, the stationary and moving obstacles are detected and the collision possibility is calculated. The velocity and direction of the obstacle are predicted using Kalman filter algorithm. Collision possibility, time, and position can be calculated by comparing the AGV movement and obstacle prediction result obtained by Kalman filter. Finally the avoidance maneuver using the well known tangent Bug algorithm is decided based on the calculation data. The effectiveness of proposed algorithm is verified using simulation and experiment. Several examples of experiment conditions are presented using stationary obstacle, and moving obstacles. The simulation and experiment results show that the AGV can detect and avoid the obstacles successfully in all experimental condition. [Keywords— Obstacle avoidance, AGV, differential drive, laser measurement system, laser navigation system].

  3. Monitoring Bone Tissue Engineered (BTE) Constructs Based on the Shifting Metabolism of Differentiating Stem Cells.

    Science.gov (United States)

    Simmons, Aaron D; Sikavitsas, Vassilios I

    2018-01-01

    Ever-increasing demand for bone grafts necessitates the realization of clinical implementation of bone tissue engineered constructs. The predominant hurdle to implementation remains to be securing FDA approval, based on the lack of viable methods for the rigorous monitoring of said constructs. The study presented herein details a method for such monitoring based on the shifting metabolism of mesenchymal stem cells (MSCs) as they differentiate into osteoblasts. To that end, rat MSCs seeded on 85% porous spunbonded poly(L-lactic acid) scaffolds were cultured in flow perfusion bioreactors with baseline or osteoinductive media, and levels of key physio-metabolic markers (oxygen, glucose, osteoprotegerin, and osteocalcin) were monitored throughout culture. Comparison of these non-destructively obtained values and current standard destructive analyses demonstrated key trends useful for the concurrent real-time monitoring of construct cellularity and maturation. Principle among these is the elucidation of the ratio of the rates of oxygen uptake to glucose consumption as a powerful quality marker. This ratio, supported on a physiological basis, has been shown herein to be reliable in the determination of both construct maturation (defined as osteoblastic differentiation and accompanying mineralization) and construct cellularity. Supplementary monitoring of OPG and OCN are shown to provide further validation of such metrics.

  4. On computing Gröbner bases in rings of differential operators

    Science.gov (United States)

    Ma, Xiaodong; Sun, Yao; Wang, Dingkang

    2011-05-01

    Insa and Pauer presented a basic theory of Groebner basis for differential operators with coefficients in a commutative ring in 1998, and a criterion was proposed to determine if a set of differential operators is a Groebner basis. In this paper, we will give a new criterion such that Insa and Pauer's criterion could be concluded as a special case and one could compute the Groebner basis more efficiently by this new criterion.

  5. On new solutions of fuzzy differential equations

    International Nuclear Information System (INIS)

    Chalco-Cano, Y.; Roman-Flores, H.

    2008-01-01

    We study fuzzy differential equations (FDE) using the concept of generalized H-differentiability. This concept is based in the enlargement of the class of differentiable fuzzy mappings and, for this, we consider the lateral Hukuhara derivatives. We will see that both derivatives are different and they lead us to different solutions from a FDE. Also, some illustrative examples are given and some comparisons with other methods for solving FDE are made

  6. Selective phosphorylation during early macrophage differentiation

    KAUST Repository

    Zhang, Huoming

    2015-08-26

    The differentiation of macrophages from monocytes is a tightly controlled and complex biological process. Although numerous studies have been conducted using biochemical approaches or global gene/gene profiling, the mechanisms of the early stages of differentiation remain unclear. Here we used SILAC-based quantitative proteomics approach to perform temporal phosphoproteome profiling of early macrophage differentiation. We identified a large set of phosphoproteins and grouped them as PMA-regulated and non-regulated phosphoproteins in the early stages of differentiation. Further analysis of the PMA-regulated phosphoproteins revealed that transcriptional suppression, cytoskeletal reorganization and cell adhesion were among the most significantly activated pathways. Some key involved regulators of these pathways are mTOR, MYB, STAT1 and CTNNB. Moreover, we were able to classify the roles and activities of several transcriptional factors during different differentiation stages and found that E2F is likely to be an important regulator during the relatively late stages of differentiation. This study provides the first comprehensive picture of the dynamic phosphoproteome during myeloid cells differentiation, and identifies potential molecular targets in leukemic cells.

  7. Education based thinking and behaving? Towards an identity perspective for studying education differentials in public opinion and political participation

    NARCIS (Netherlands)

    Spruyt, Bram; Kuppens, Toon

    2015-01-01

    Education based thinking and behaving? Towards and identity perspective for studying education differentials in public opinion and political participation Abstract Ever since scholars started studying public opinion and political behaviour, they have reported substantial educational differences.

  8. Toward a non-invasive screening tool for differentiation of pancreatic lesions based on intra-voxel incoherent motion derived parameters

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Markus; Simon, Dirk; Mang, Sarah [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Software Development for Integrated Therapy and Diagnostics; Lemke, Andreas [Heidelberg Univ., Mannheim (Germany). Dept. of Computer Assisted Clinical Medicine; Gruenberg, Katharina [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Dept. of Radiology

    2013-03-01

    Early recognition of and differential diagnosis between pancreatic cancer and chronic pancreatitis is an important step in successful therapy. Parameters of the IVIM (intra-voxel incoherent motion) theory can be used to differentiate between those lesions. The objective of this work is to evaluate the effects of rigid image registration on IVIM derived parameters for differentiation of pancreatic lesions such as pancreatic cancer and solid mass forming pancreatitis. The effects of linear image registration methods on reproducibility and accuracy of IVIM derived parameters were quantified on MR images of ten volunteers. For this purpose, they were evaluated statistically by comparison of registered and unregistered parameter data. Further, the perfusion fraction f was used to differentiate pancreatic lesions on eleven previously diagnosed patient data sets. Its diagnostic power with and without rigid registration was evaluated using receiver operating curves (ROC) analysis. The pancreas was segmented manually on MR data sets of healthy volunteers as well as the patients showing solid pancreatic lesions. Diffusion weighted imaging was performed in 10 blocks of breath-hold phases. Linear registration of the weighted image stack leads to a 3.7% decrease in variability of the IVIM derived parameter f due to an improved anatomical overlap of 5%. Consequently, after registration the area under the curve in the ROC-analysis for the differentiation approach increased by 2.7%. In conclusion, rigid registration improves the differentiation process based on f-values. (orig.)

  9. Toward a non-invasive screening tool for differentiation of pancreatic lesions based on intra-voxel incoherent motion derived parameters

    International Nuclear Information System (INIS)

    Graf, Markus; Simon, Dirk; Mang, Sarah; Lemke, Andreas; Gruenberg, Katharina

    2013-01-01

    Early recognition of and differential diagnosis between pancreatic cancer and chronic pancreatitis is an important step in successful therapy. Parameters of the IVIM (intra-voxel incoherent motion) theory can be used to differentiate between those lesions. The objective of this work is to evaluate the effects of rigid image registration on IVIM derived parameters for differentiation of pancreatic lesions such as pancreatic cancer and solid mass forming pancreatitis. The effects of linear image registration methods on reproducibility and accuracy of IVIM derived parameters were quantified on MR images of ten volunteers. For this purpose, they were evaluated statistically by comparison of registered and unregistered parameter data. Further, the perfusion fraction f was used to differentiate pancreatic lesions on eleven previously diagnosed patient data sets. Its diagnostic power with and without rigid registration was evaluated using receiver operating curves (ROC) analysis. The pancreas was segmented manually on MR data sets of healthy volunteers as well as the patients showing solid pancreatic lesions. Diffusion weighted imaging was performed in 10 blocks of breath-hold phases. Linear registration of the weighted image stack leads to a 3.7% decrease in variability of the IVIM derived parameter f due to an improved anatomical overlap of 5%. Consequently, after registration the area under the curve in the ROC-analysis for the differentiation approach increased by 2.7%. In conclusion, rigid registration improves the differentiation process based on f-values. (orig.)

  10. Individual responsibility, solidarity and differentiation in healthcare

    NARCIS (Netherlands)

    Stegeman, I.; Willems, D. L.; Dekker, E.; Bossuyt, P. M.

    2014-01-01

    Access to healthcare in most western societies is based on equality. Rapidly rising costs have fuelled debates about differentiation in access to healthcare. We assessed the public's perceptions and attitudes about differentiation in healthcare according to lifestyle behaviour. A vignette study was

  11. A Sensitive ANN Based Differential Relay for Transformer Protection with Security against CT Saturation and Tap Changer Operation

    OpenAIRE

    KHORASHADI-ZADEH, Hassan; LI, Zuyi

    2014-01-01

    This paper presents an artificial neural network (ANN) based scheme for fault identification in power transformer protection. The proposed scheme is featured by the application of ANN to identifying system patterns, the unique choice of harmonics of positive sequence differential currents as ANN inputs, the effective handling of current transformer (CT) saturation with an ANN based approach, and the consideration of tap changer position for correcting secondary CT current. Performanc...

  12. Discrimination Between Inrush and Short Circuit Currents in Differential Protection of Power Transformer Based on Correlation Method Using the Wavelet Transform

    OpenAIRE

    M. Rasoulpoor; M. Banejad; A. Ahmadyfard

    2011-01-01

    This paper presents a novel technique for transformer differential protection to prevent incorrect operation due to inrush current. The proposed method in this paper is based on time-frequency transform known as the Wavelet transform. The discrete Wavelet transform is used for analysis the differential current signals in time and frequency domains. The investigation on the energy distribution of the signal on the discrete Wavelet transform components shows the difference distribution between ...

  13. Optical solver for a system of ordinary differential equations based on an external feedback assisted microring resonator.

    Science.gov (United States)

    Hou, Jie; Dong, Jianji; Zhang, Xinliang

    2017-06-15

    Systems of ordinary differential equations (SODEs) are crucial for describing the dynamic behaviors in various systems such as modern control systems which require observability and controllability. In this Letter, we propose and experimentally demonstrate an all-optical SODE solver based on the silicon-on-insulator platform. We use an add/drop microring resonator to construct two different ordinary differential equations (ODEs) and then introduce two external feedback waveguides to realize the coupling between these ODEs, thus forming the SODE solver. A temporal coupled mode theory is used to deduce the expression of the SODE. A system experiment is carried out for further demonstration. For the input 10 GHz NRZ-like pulses, the measured output waveforms of the SODE solver agree well with the calculated results.

  14. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... Differentiation is mostly based on binary decisions with the progenitor cells ..... accounts for the dominant part of the remaining variation ... significant loss in information. ..... making in vitro: emerging concepts and novel tools.

  15. A differential transformation approach for solving functional differential equations with multiple delays

    Science.gov (United States)

    Rebenda, Josef; Šmarda, Zdeněk

    2017-07-01

    In the paper an efficient semi-analytical approach based on the method of steps and the differential transformation is proposed for numerical approximation of solutions of functional differential models of delayed and neutral type on a finite interval of arbitrary length, including models with several constant delays. Algorithms for both commensurate and non-commensurate delays are described, applications are shown in examples. Validity and efficiency of the presented algorithms is compared with the variational iteration method, the Adomian decomposition method and the polynomial least squares method numerically. Matlab package DDE23 is used to produce reference numerical values.

  16. Rolling Force Prediction in Heavy Plate Rolling Based on Uniform Differential Neural Network

    Directory of Open Access Journals (Sweden)

    Fei Zhang

    2016-01-01

    Full Text Available Accurate prediction of the rolling force is critical to assuring the quality of the final product in steel manufacturing. Exit thickness of plate for each pass is calculated from roll gap, mill spring, and predicted roll force. Ideal pass scheduling is dependent on a precise prediction of the roll force in each pass. This paper will introduce a concept that allows obtaining the material model parameters directly from the rolling process on an industrial scale by the uniform differential neural network. On the basis of the characteristics that the uniform distribution can fully characterize the solution space and enhance the diversity of the population, uniformity research on differential evolution operator is made to get improved crossover with uniform distribution. When its original function is transferred with a transfer function, the uniform differential evolution algorithms can quickly solve complex optimization problems. Neural network structure and weights threshold are optimized by uniform differential evolution algorithm, and a uniform differential neural network is formed to improve rolling force prediction accuracy in process control system.

  17. Inverse Regulation of Early and Late Chondrogenic Differentiation by Oxygen Tension Provides Cues for Stem Cell-Based Cartilage Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Sophie Portron

    2015-01-01

    Full Text Available Background/Aims: Multipotent stem/stromal cells (MSC are considered promising for cartilage tissue engineering. However, chondrogenic differentiation of MSC can ultimately lead to the formation of hypertrophic chondrocytes responsible for the calcification of cartilage. To prevent the production of this calcified matrix at the articular site, the late hypertrophic differentiation of MSCs must be carefully controlled. Given that articular cartilage is avascular, we hypothesized that in addition to its stimulatory role in the early differentiation of chondrogenic cells, hypoxia may prevent their late hypertrophic conversion. Methods: Early and late chondrogenic differentiation were evaluated using human adipose MSC and murine ATDC5 cells cultured under either normoxic (21%O2 or hypoxic (5%O2 conditions. To investigate the effect of hypoxia on late chondrogenic differentiation, the transcriptional activity of hypoxia-inducible factor-1alpha (HIF-1α and HIF-2α were evaluated using the NoShift DNA-binding assay and through modulation of their activity (chemical inhibitor, RNA interference. Results: Our data demonstrate that low oxygen tension not only stimulates the early chondrogenic commitment of two complementary models of chondrogenic cells, but also inhibits their hypertrophic differentiation. Conclusion: These results suggest that hypoxia can be used as an instrumental tool to prevent the formation of a calcified matrix in MSC-based cartilage tissue engineering.

  18. Algorithmic differentiation of pragma-defined parallel regions differentiating computer programs containing OpenMP

    CERN Document Server

    Förster, Michael

    2014-01-01

    Numerical programs often use parallel programming techniques such as OpenMP to compute the program's output values as efficient as possible. In addition, derivative values of these output values with respect to certain input values play a crucial role. To achieve code that computes not only the output values simultaneously but also the derivative values, this work introduces several source-to-source transformation rules. These rules are based on a technique called algorithmic differentiation. The main focus of this work lies on the important reverse mode of algorithmic differentiation. The inh

  19. Living biointerfaces based on non-pathogenic bacteria support stem cell differentiation

    Science.gov (United States)

    Hay, Jake J.; Rodrigo-Navarro, Aleixandre; Hassi, Karoliina; Moulisova, Vladimira; Dalby, Matthew J.; Salmeron-Sanchez, Manuel

    2016-02-01

    Lactococcus lactis, a non-pathogenic bacteria, has been genetically engineered to express the III7-10 fragment of human fibronectin as a membrane protein. The engineered L. lactis is able to develop biofilms on different surfaces (such as glass and synthetic polymers) and serves as a long-term substrate for mammalian cell culture, specifically human mesenchymal stem cells (hMSC). This system constitutes a living interface between biomaterials and stem cells. The engineered biofilms remain stable and viable for up to 28 days while the expressed fibronectin fragment induces hMSC adhesion. We have optimised conditions to allow long-term mammalian cell culture, and found that the biofilm is functionally equivalent to a fibronectin-coated surface in terms of osteoblastic differentiation using bone morphogenetic protein 2 (BMP-2) added to the medium. This living bacteria interface holds promise as a dynamic substrate for stem cell differentiation that can be further engineered to express other biochemical cues to control hMSC differentiation.

  20. Introductory course on differential equations

    CERN Document Server

    Gorain, Ganesh C

    2014-01-01

    Introductory Course on DIFFERENTIAL EQUATIONS provides an excellent exposition of the fundamentals of ordinary and partial differential equations and is ideally suited for a first course of undergraduate students of mathematics, physics and engineering. The aim of this book is to present the elementary theories of differential equations in the forms suitable for use of those students whose main interest in the subject are based on simple mathematical ideas. KEY FEATURES: Discusses the subject in a systematic manner without sacrificing mathematical rigour. A variety of exercises drill the students in problem solving in view of the mathematical theories explained in the book. Worked out examples illustrated according to the theories developed in the book with possible alternatives. Exhaustive collection of problems and the simplicity of presentation differentiate this book from several others. Material contained will help teachers as well as aspiring students of different competitive examinations.

  1. Bounded solutions for fuzzy differential and integral equations

    Energy Technology Data Exchange (ETDEWEB)

    Nieto, Juan J. [Departamento de Analisis Matematico Facultad de Matematicas Universidad de Santiago de Compostela, 15782 (Spain)] e-mail: amnieto@usc.es; Rodriguez-Lopez, Rosana [Departamento de Analisis Matematico Facultad de Matematicas Universidad de Santiago de Compostela, 15782 (Spain)] e-mail: amrosana@usc.es

    2006-03-01

    We find sufficient conditions for the boundness of every solution of first-order fuzzy differential equations as well as certain fuzzy integral equations. Our results are based on several theorems concerning crisp differential and integral inequalities.

  2. Brand positioning strategies : an expiremental test ot two types of benefit differentiation

    OpenAIRE

    Hem, Alexander Farestvedt; Teslo, Per Christian Strand

    2012-01-01

    The purpose of this study is to examine associative- and instrumental benefit differentiation based on secondary associations as part of brand positioning. The field of brand positioning has been subject to extensive research, however, differentiation based on secondary associations and differences between instrumental- and associative benefit differentiation has received less attention. Instrumental benefit differentiation relates to benefits that are linked directly to product performance, ...

  3. Modulating Functions Based Algorithm for the Estimation of the Coefficients and Differentiation Order for a Space-Fractional Advection-Dispersion Equation

    KAUST Repository

    Aldoghaither, Abeer

    2015-12-01

    In this paper, a new method, based on the so-called modulating functions, is proposed to estimate average velocity, dispersion coefficient, and differentiation order in a space-fractional advection-dispersion equation, where the average velocity and the dispersion coefficient are space-varying. First, the average velocity and the dispersion coefficient are estimated by applying the modulating functions method, where the problem is transformed into a linear system of algebraic equations. Then, the modulating functions method combined with a Newton\\'s iteration algorithm is applied to estimate the coefficients and the differentiation order simultaneously. The local convergence of the proposed method is proved. Numerical results are presented with noisy measurements to show the effectiveness and robustness of the proposed method. It is worth mentioning that this method can be extended to general fractional partial differential equations.

  4. Modulating Functions Based Algorithm for the Estimation of the Coefficients and Differentiation Order for a Space-Fractional Advection-Dispersion Equation

    KAUST Repository

    Aldoghaither, Abeer; Liu, Da-Yan; Laleg-Kirati, Taous-Meriem

    2015-01-01

    In this paper, a new method, based on the so-called modulating functions, is proposed to estimate average velocity, dispersion coefficient, and differentiation order in a space-fractional advection-dispersion equation, where the average velocity and the dispersion coefficient are space-varying. First, the average velocity and the dispersion coefficient are estimated by applying the modulating functions method, where the problem is transformed into a linear system of algebraic equations. Then, the modulating functions method combined with a Newton's iteration algorithm is applied to estimate the coefficients and the differentiation order simultaneously. The local convergence of the proposed method is proved. Numerical results are presented with noisy measurements to show the effectiveness and robustness of the proposed method. It is worth mentioning that this method can be extended to general fractional partial differential equations.

  5. The effect of differential training-based occupational therapy on hand and arm function in patients after stroke: Results of the pilot study.

    Science.gov (United States)

    Repšaitė, Viktorija; Vainoras, Alfonsas; Berškienė, Kristina; Baltaduonienė, Daiva; Daunoravičienė, Algė; Sendžikaitė, Ernesta

    2015-01-01

    The aim of this study was to evaluate the effect of differential training-based occupational therapy on the recovery of arm function and to compare these data with the results obtained after conventional occupational therapy. A total of 27 patients who had suffered a cerebral infarction in the left brain hemisphere were recruited for the study. There were 9 men (33.33%) and 18 women (66.67%). All the patients had paresis of the right arm. The patients were divided into 2 groups: the control group comprised 15 patients who were given conventional occupational therapy (5 times per week) and the study group consisted of 12 patients who underwent conventional occupational therapy (3 times per week) along with occupational therapy based on differential training (2 times per week). In the control group, the mean performance time of only 2 tasks, i.e., flip cards and fold towel, improved significantly (Poccupational therapy sessions, but the patients who underwent conventional occupational therapy along with differential training-based occupational therapy recovered their arm function more effectively than their counterparts after conventional occupational therapy. Copyright © 2015 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  6. Teacher Implementation of Trial-Based Functional Analysis and Differential Reinforcement of Alternative Behavior for Students with Challenging Behavior

    Science.gov (United States)

    Flynn, Susan D.; Lo, Ya-yu

    2016-01-01

    The purpose of this study was to examine the effects of a training package on three middle school special education teachers' accurate implementation of trial-based functional analysis (TBFA) and differential reinforcement of alternative behavior (DRA) with their students with autism spectrum disorders or emotional and behavioral disorders in the…

  7. Density-based Monte Carlo filter and its applications in nonlinear stochastic differential equation models.

    Science.gov (United States)

    Huang, Guanghui; Wan, Jianping; Chen, Hui

    2013-02-01

    Nonlinear stochastic differential equation models with unobservable state variables are now widely used in analysis of PK/PD data. Unobservable state variables are usually estimated with extended Kalman filter (EKF), and the unknown pharmacokinetic parameters are usually estimated by maximum likelihood estimator. However, EKF is inadequate for nonlinear PK/PD models, and MLE is known to be biased downwards. A density-based Monte Carlo filter (DMF) is proposed to estimate the unobservable state variables, and a simulation-based M estimator is proposed to estimate the unknown parameters in this paper, where a genetic algorithm is designed to search the optimal values of pharmacokinetic parameters. The performances of EKF and DMF are compared through simulations for discrete time and continuous time systems respectively, and it is found that the results based on DMF are more accurate than those given by EKF with respect to mean absolute error. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. How to differentiate acute pelvic inflammatory disease from acute appendicitis? A decision tree based on CT findings

    Energy Technology Data Exchange (ETDEWEB)

    El Hentour, Kim; Millet, Ingrid; Pages-Bouic, Emmanuelle; Curros-Doyon, Fernanda; Taourel, Patrice [Lapeyronie Hospital, Department of Medical Imaging, Montpellier (France); Molinari, Nicolas [UMR 5149 IMAG, CHU, Department of Medical Information and Statistics, Montpellier (France)

    2018-02-15

    To construct a decision tree based on CT findings to differentiate acute pelvic inflammatory disease (PID) from acute appendicitis (AA) in women with lower abdominal pain and inflammatory syndrome. This retrospective study was approved by our institutional review board and informed consent was waived. Contrast-enhanced CT studies of 109 women with acute PID and 218 age-matched women with AA were retrospectively and independently reviewed by two radiologists to identify CT findings predictive of PID or AA. Surgical and laboratory data were used for the PID and AA reference standard. Appropriate tests were performed to compare PID and AA and a CT decision tree using the classification and regression tree (CART) algorithm was generated. The median patient age was 28 years (interquartile range, 22-39 years). According to the decision tree, an appendiceal diameter ≥ 7 mm was the most discriminating criterion for differentiating acute PID and AA, followed by a left tubal diameter ≥ 10 mm, with a global accuracy of 98.2 % (95 % CI: 96-99.4). Appendiceal diameter and left tubal thickening are the most discriminating CT criteria for differentiating acute PID from AA. (orig.)

  9. How to differentiate acute pelvic inflammatory disease from acute appendicitis? A decision tree based on CT findings

    International Nuclear Information System (INIS)

    El Hentour, Kim; Millet, Ingrid; Pages-Bouic, Emmanuelle; Curros-Doyon, Fernanda; Taourel, Patrice; Molinari, Nicolas

    2018-01-01

    To construct a decision tree based on CT findings to differentiate acute pelvic inflammatory disease (PID) from acute appendicitis (AA) in women with lower abdominal pain and inflammatory syndrome. This retrospective study was approved by our institutional review board and informed consent was waived. Contrast-enhanced CT studies of 109 women with acute PID and 218 age-matched women with AA were retrospectively and independently reviewed by two radiologists to identify CT findings predictive of PID or AA. Surgical and laboratory data were used for the PID and AA reference standard. Appropriate tests were performed to compare PID and AA and a CT decision tree using the classification and regression tree (CART) algorithm was generated. The median patient age was 28 years (interquartile range, 22-39 years). According to the decision tree, an appendiceal diameter ≥ 7 mm was the most discriminating criterion for differentiating acute PID and AA, followed by a left tubal diameter ≥ 10 mm, with a global accuracy of 98.2 % (95 % CI: 96-99.4). Appendiceal diameter and left tubal thickening are the most discriminating CT criteria for differentiating acute PID from AA. (orig.)

  10. Dielectric metasurfaces solve differential and integro-differential equations.

    Science.gov (United States)

    Abdollahramezani, Sajjad; Chizari, Ata; Dorche, Ali Eshaghian; Jamali, Mohammad Vahid; Salehi, Jawad A

    2017-04-01

    Leveraging subwavelength resonant nanostructures, plasmonic metasurfaces have recently attracted much attention as a breakthrough concept for engineering optical waves both spatially and spectrally. However, inherent ohmic losses concomitant with low coupling efficiencies pose fundamental impediments over their practical applications. Not only can all-dielectric metasurfaces tackle such substantial drawbacks, but also their CMOS-compatible configurations support both Mie resonances that are invariant to the incident angle. Here, we report on a transmittive metasurface comprising arrayed silicon nanodisks embedded in a homogeneous dielectric medium to manipulate phase and amplitude of incident light locally and almost independently. By taking advantage of the interplay between the electric/magnetic resonances and employing general concepts of spatial Fourier transformation, a highly efficient metadevice is proposed to perform mathematical operations including solution of ordinary differential and integro-differential equations with constant coefficients. Our findings further substantiate dielectric metasurfaces as promising candidates for miniaturized, two-dimensional, and planar optical analog computing systems that are much thinner than their conventional lens-based counterparts.

  11. Differential proteomics analysis to identify proteins and pathways associated with male sterility of soybean using iTRAQ-based strategy.

    Science.gov (United States)

    Li, Jiajia; Ding, Xianlong; Han, Shaohuai; He, Tingting; Zhang, Hao; Yang, Longshu; Yang, Shouping; Gai, Junyi

    2016-04-14

    To further elucidate the molecular mechanism of cytoplasmic male sterility (CMS) in soybean, a differential proteomic analysis was completed between the CMS line NJCMS1A and its maintainer NJCMS1B using iTRAQ-based strategy. As a result, 180 differential abundance proteins (DAPs) were identified, of which, 60 were down-regulated and 120 were up-regulated in NJCMS1A compared with NJCMS1B. Bioinformatic analysis showed that 167 DAPs were annotated in 41 Gene Ontology functional groups, 106 DAPs were classified into 20 clusters of orthologous groups of protein categories, and 128 DAPs were enrichment in 53 KEGG pathways. Fifteen differential level proteins/genes with the same expression pattern were identified in the further conjoint analysis of DAPs and the previously reported differential expression genes. Moreover, multiple reaction monitoring test, qRT-PCR analysis and enzyme activity assay validated that the iTRAQ results were reliable. Based on functional analysis of DAPs, we concluded that male sterility in NJCMS1A might be related to insufficiencies in energy supply, unbalance of protein synthesis and degradation, disruption of flavonoid synthesis, programmed cell death, abnormalities of substance metabolism, etc. These results might facilitate our understanding of the molecular mechanisms behind CMS in soybean. Soybean is an important global crop that provides protein and oil. Heterosis is a significantly potential approach to increase the yield of soybean. Cytoplasmic male sterility (CMS) plays a vital role in the production of hybrid seeds. However, the genetic and molecular mechanisms of male sterility in soybean still need to be further elucidated. In the present paper, a differential proteomic analysis was carried out and the results showed that several key proteins involved in key pathways were associated with male sterility in soybean. This work provides a new insight to understand the genetic and molecular mechanisms underlying CMS in soybean

  12. Integro-differential transport approaches

    International Nuclear Information System (INIS)

    Stepanek, J.; Arkuszewski, J.; Boffi, V.; Matausek, M.V.

    1981-01-01

    This chapter summarizes the work done in Italy, Poland, Switzerland and Yugoslavia in the field of integro-differential neutron transport theory. It reflects different viewpoints in the handling of the subject. Some of the methods are based only on the solution of the integro-differential equation, others use only the integral form of the transport equation. Use of the characteristic solution closely related to the integral equation (ARKUSZEWSKI et al.,(1979)) seems to be a rather effective way to accelerate the 2 dimensional discrete ordinates (Ssub(n)) transport methods and supress one of the main disadvantages, the ray effect. The advanced ''Surface Currents'' (MAEDER (1975)) and ''Surface Flux'' (STEPANEK (1979)) methods are based on the solution of both the integro-differential and integral form of the transport equation. As long as the spatial fluxes were considered to be flat in each region only the integral form of the transport equation was considered. The solution seems to be the best method of simple handling the higher order Legendre polynomials used to approximate spatial and angular flux distribution. The coupling of the Bsub(n) integral transport equations with the related Psub(n) equations removes the greatest disadvantage of the Psub(n) theory and closes the system of the Psub(n) equations (LIGOU, STEPANEK (1974))

  13. Differential pseudoconnections and field theories

    International Nuclear Information System (INIS)

    Modugno, Marco; Ragionieri, Rodolfo; Stefani, Gianna

    1981-01-01

    Several general field theories have been successful in describing fundamental physical fields by a unique schema. Our purpose is to present the first step of an attempt based on differential pseudoconnections on jet bundles. In this paper we are dealing with the essential elements of such an approach and with the testing of a certain number of important examples. We define a 'differential pseudoconnection of order k' on a bundle p:E→M as a translation morphism on the affine bundle. Such concept is a generalization of usual connections. Then we study in the framework of jet spaces several important differential operators used in physics. In this context an interest arises naturally for the second order affine differential equations, called 'special'. Particular cases of special equations are both the geodesics equation (an ordinary equation) and any Kind of Laplace equation (a partial equation) even modified by the addition of physical terms. So special equations are candidate to fit a lot of fundamental physical fields

  14. Differential magnetic force microscope imaging.

    Science.gov (United States)

    Wang, Ying; Wang, Zuobin; Liu, Jinyun; Hou, Liwei

    2015-01-01

    This paper presents a method for differential magnetic force microscope imaging based on a two-pass scanning procedure to extract differential magnetic forces and eliminate or significantly reduce background forces with reversed tip magnetization. In the work, the difference of two scanned images with reversed tip magnetization was used to express the local magnetic forces. The magnetic sample was first scanned with a low lift distance between the MFM tip and the sample surface, and the magnetization direction of the probe was then changed after the first scan to perform the second scan. The differential magnetic force image was obtained through the subtraction of the two images from the two scans. The theoretical and experimental results have shown that the proposed method for differential magnetic force microscope imaging is able to reduce the effect of background or environment interference forces, and offers an improved image contrast and signal to noise ratio (SNR). © Wiley Periodicals, Inc.

  15. New Collaborative Filtering Algorithms Based on SVD++ and Differential Privacy

    Directory of Open Access Journals (Sweden)

    Zhengzheng Xian

    2017-01-01

    Full Text Available Collaborative filtering technology has been widely used in the recommender system, and its implementation is supported by the large amount of real and reliable user data from the big-data era. However, with the increase of the users’ information-security awareness, these data are reduced or the quality of the data becomes worse. Singular Value Decomposition (SVD is one of the common matrix factorization methods used in collaborative filtering, which introduces the bias information of users and items and is realized by using algebraic feature extraction. The derivative model SVD++ of SVD achieves better predictive accuracy due to the addition of implicit feedback information. Differential privacy is defined very strictly and can be proved, which has become an effective measure to solve the problem of attackers indirectly deducing the personal privacy information by using background knowledge. In this paper, differential privacy is applied to the SVD++ model through three approaches: gradient perturbation, objective-function perturbation, and output perturbation. Through theoretical derivation and experimental verification, the new algorithms proposed can better protect the privacy of the original data on the basis of ensuring the predictive accuracy. In addition, an effective scheme is given that can measure the privacy protection strength and predictive accuracy, and a reasonable range for selection of the differential privacy parameter is provided.

  16. Gender-Based Differential Item Performance in Mathematics Achievement Items.

    Science.gov (United States)

    Doolittle, Allen E.; Cleary, T. Anne

    1987-01-01

    Eight randomly equivalent samples of high school seniors were each given a unique form of the ACT Assessment Mathematics Usage Test (ACTM). Signed measures of differential item performance (DIP) were obtained for each item in the eight ACTM forms. DIP estimates were analyzed and a significant item category effect was found. (Author/LMO)

  17. Generalized differential transform method to differential-difference equation

    International Nuclear Information System (INIS)

    Zou Li; Wang Zhen; Zong Zhi

    2009-01-01

    In this Letter, we generalize the differential transform method to solve differential-difference equation for the first time. Two simple but typical examples are applied to illustrate the validity and the great potential of the generalized differential transform method in solving differential-difference equation. A Pade technique is also introduced and combined with GDTM in aim of extending the convergence area of presented series solutions. Comparisons are made between the results of the proposed method and exact solutions. Then we apply the differential transform method to the discrete KdV equation and the discrete mKdV equation, and successfully obtain solitary wave solutions. The results reveal that the proposed method is very effective and simple. We should point out that generalized differential transform method is also easy to be applied to other nonlinear differential-difference equation.

  18. Advanced differential quadrature methods

    CERN Document Server

    Zong, Zhi

    2009-01-01

    Modern Tools to Perform Numerical DifferentiationThe original direct differential quadrature (DQ) method has been known to fail for problems with strong nonlinearity and material discontinuity as well as for problems involving singularity, irregularity, and multiple scales. But now researchers in applied mathematics, computational mechanics, and engineering have developed a range of innovative DQ-based methods to overcome these shortcomings. Advanced Differential Quadrature Methods explores new DQ methods and uses these methods to solve problems beyond the capabilities of the direct DQ method.After a basic introduction to the direct DQ method, the book presents a number of DQ methods, including complex DQ, triangular DQ, multi-scale DQ, variable order DQ, multi-domain DQ, and localized DQ. It also provides a mathematical compendium that summarizes Gauss elimination, the Runge-Kutta method, complex analysis, and more. The final chapter contains three codes written in the FORTRAN language, enabling readers to q...

  19. Low-Power Differential SRAM design for SOC Based on the 25-um Technology

    Science.gov (United States)

    Godugunuri, Sivaprasad; Dara, Naveen; Sambasiva Nayak, R.; Nayeemuddin, Md; Singh, Yadu, Dr.; Veda, R. N. S. Sunil

    2017-08-01

    In recent, the SOC styles area unit the vast complicated styles in VLSI these SOC styles having important low-power operations problems, to comprehend this we tend to enforced low-power SRAM. However these SRAM Architectures critically affects the entire power of SOC and competitive space. To beat the higher than disadvantages, during this paper, a low-power differential SRAM design is planned. The differential SRAM design stores multiple bits within the same cell, operates at minimum in operation low-tension and space per bit. The differential SRAM design designed supported the 25-um technology using Tanner-EDA Tool.

  20. Fluorescent polymer-based post-translational differentiation and subtyping of breast cancer cells.

    Science.gov (United States)

    Scott, Michael D; Dutta, Rinku; Haldar, Manas K; Wagh, Anil; Gustad, Thomas R; Law, Benedict; Friesner, Daniel L; Mallik, Sanku

    2012-12-07

    Herein, we report the application of synthesized fluorescent, water soluble polymers for post-translational subtyping and differentiation of breast cancer cells in vitro. The fluorescence emission spectra from these polymers were modulated differently in the presence of conditioned cell culture media from various breast cancer cells. These polymers differentiate at a post-translation level possibly due to their ability to interact with extracellular enzymes that are over-expressed in cancerous conditions.

  1. Differential stabilities and sequence-dependent base pair opening dynamics of Watson-Crick base pairs with 5-hydroxymethylcytosine, 5-formylcytosine, or 5-carboxylcytosine.

    Science.gov (United States)

    Szulik, Marta W; Pallan, Pradeep S; Nocek, Boguslaw; Voehler, Markus; Banerjee, Surajit; Brooks, Sonja; Joachimiak, Andrzej; Egli, Martin; Eichman, Brandt F; Stone, Michael P

    2015-02-10

    5-Hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC) form during active demethylation of 5-methylcytosine (5mC) and are implicated in epigenetic regulation of the genome. They are differentially processed by thymine DNA glycosylase (TDG), an enzyme involved in active demethylation of 5mC. Three modified Dickerson-Drew dodecamer (DDD) sequences, amenable to crystallographic and spectroscopic analyses and containing the 5'-CG-3' sequence associated with genomic cytosine methylation, containing 5hmC, 5fC, or 5caC placed site-specifically into the 5'-T(8)X(9)G(10)-3' sequence of the DDD, were compared. The presence of 5caC at the X(9) base increased the stability of the DDD, whereas 5hmC or 5fC did not. Both 5hmC and 5fC increased imino proton exchange rates and calculated rate constants for base pair opening at the neighboring base pair A(5):T(8), whereas 5caC did not. At the oxidized base pair G(4):X(9), 5fC exhibited an increase in the imino proton exchange rate and the calculated kop. In all cases, minimal effects to imino proton exchange rates occurred at the neighboring base pair C(3):G(10). No evidence was observed for imino tautomerization, accompanied by wobble base pairing, for 5hmC, 5fC, or 5caC when positioned at base pair G(4):X(9); each favored Watson-Crick base pairing. However, both 5fC and 5caC exhibited intranucleobase hydrogen bonding between their formyl or carboxyl oxygens, respectively, and the adjacent cytosine N(4) exocyclic amines. The lesion-specific differences observed in the DDD may be implicated in recognition of 5hmC, 5fC, or 5caC in DNA by TDG. However, they do not correlate with differential excision of 5hmC, 5fC, or 5caC by TDG, which may be mediated by differences in transition states of the enzyme-bound complexes.

  2. Differential Stabilities and Sequence-Dependent Base Pair Opening Dynamics of Watson–Crick Base Pairs with 5-Hydroxymethylcytosine, 5-Formylcytosine, or 5-Carboxylcytosine

    Science.gov (United States)

    2016-01-01

    5-Hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC) form during active demethylation of 5-methylcytosine (5mC) and are implicated in epigenetic regulation of the genome. They are differentially processed by thymine DNA glycosylase (TDG), an enzyme involved in active demethylation of 5mC. Three modified Dickerson–Drew dodecamer (DDD) sequences, amenable to crystallographic and spectroscopic analyses and containing the 5′-CG-3′ sequence associated with genomic cytosine methylation, containing 5hmC, 5fC, or 5caC placed site-specifically into the 5′-T8X9G10-3′ sequence of the DDD, were compared. The presence of 5caC at the X9 base increased the stability of the DDD, whereas 5hmC or 5fC did not. Both 5hmC and 5fC increased imino proton exchange rates and calculated rate constants for base pair opening at the neighboring base pair A5:T8, whereas 5caC did not. At the oxidized base pair G4:X9, 5fC exhibited an increase in the imino proton exchange rate and the calculated kop. In all cases, minimal effects to imino proton exchange rates occurred at the neighboring base pair C3:G10. No evidence was observed for imino tautomerization, accompanied by wobble base pairing, for 5hmC, 5fC, or 5caC when positioned at base pair G4:X9; each favored Watson–Crick base pairing. However, both 5fC and 5caC exhibited intranucleobase hydrogen bonding between their formyl or carboxyl oxygens, respectively, and the adjacent cytosine N4 exocyclic amines. The lesion-specific differences observed in the DDD may be implicated in recognition of 5hmC, 5fC, or 5caC in DNA by TDG. However, they do not correlate with differential excision of 5hmC, 5fC, or 5caC by TDG, which may be mediated by differences in transition states of the enzyme-bound complexes. PMID:25632825

  3. Cloud computing task scheduling strategy based on differential evolution and ant colony optimization

    Science.gov (United States)

    Ge, Junwei; Cai, Yu; Fang, Yiqiu

    2018-05-01

    This paper proposes a task scheduling strategy DEACO based on the combination of Differential Evolution (DE) and Ant Colony Optimization (ACO), aiming at the single problem of optimization objective in cloud computing task scheduling, this paper combines the shortest task completion time, cost and load balancing. DEACO uses the solution of the DE to initialize the initial pheromone of ACO, reduces the time of collecting the pheromone in ACO in the early, and improves the pheromone updating rule through the load factor. The proposed algorithm is simulated on cloudsim, and compared with the min-min and ACO. The experimental results show that DEACO is more superior in terms of time, cost, and load.

  4. An automated classification system for the differentiation of obstructive lung diseases based on the textural analysis of HRCT images

    International Nuclear Information System (INIS)

    Park, Seong Hoon; Seo, Joon Beom; Kim, Nam Kug; Lee, Young Kyung; Kim, Song Soo; Chae, Eun Jin; Lee, June Goo

    2007-01-01

    To develop an automated classification system for the differentiation of obstructive lung diseases based on the textural analysis of HRCT images, and to evaluate the accuracy and usefulness of the system. For textural analysis, histogram features, gradient features, run length encoding, and a co-occurrence matrix were employed. A Bayesian classifier was used for automated classification. The images (image number n = 256) were selected from the HRCT images obtained from 17 healthy subjects (n = 67), 26 patients with bronchiolitis obliterans (n = 70), 28 patients with mild centrilobular emphysema (n = 65), and 21 patients with panlobular emphysema or severe centrilobular emphysema (n = 63). An five-fold cross-validation method was used to assess the performance of the system. Class-specific sensitivities were analyzed and the overall accuracy of the system was assessed with kappa statistics. The sensitivity of the system for each class was as follows: normal lung 84.9%, bronchiolitis obliterans 83.8%, mild centrilobular emphysema 77.0%, and panlobular emphysema or severe centrilobular emphysema 95.8%. The overall performance for differentiating each disease and the normal lung was satisfactory with a kappa value of 0.779. An automated classification system for the differentiation between obstructive lung diseases based on the textural analysis of HRCT images was developed. The proposed system discriminates well between the various obstructive lung diseases and the normal lung

  5. Poorly-differentiated colorectal neuroendocrine tumour: CT differentiation from well-differentiated neuroendocrine tumour and poorly-differentiated adenocarcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Ji Hee [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Se Hyung [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Han, Joon Koo [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of)

    2017-09-15

    The differentiation of poorly-differentiated neuroendocrine tumours (PD-NETs), well-differentiated NETs (WD-NETs), and adenocarcinomas (ADCs) is important due to different management options and prognoses. This study is to find the differential CT features of colorectal PD-NETs from WD-NETs and ADCs. CT features of 25 colorectal WD-NETs, 36 PD-NETs, and 36 ADCs were retrospectively reviewed. Significant variables were assessed using univariate and multivariate analyses. Receiver operating characteristics analysis determined the optimal cut-off value of tumour and lymph node (LN) size. Large size, rectum location, ulceroinfiltrative morphology without intact overlying mucosa, heterogeneous attenuation with necrosis, presence of ≥3 enlarged LNs, and metastasis were significant variables to differentiate PD-NETs from WD-NETs (P < 0.05). High attenuation on arterial phase, persistently high enhancement pattern, presence of ≥6 enlarged LNs, large LN size, and wash-in/wash-out enhancement pattern of liver metastasis were significant variables to differentiate PD-NETs from ADCs (P < 0.05). Compared to WD-NETs, colorectal PD-NETs are usually large, heterogeneous, and ulceroinfiltrative mass without intact overlying mucosa involving enlarged LNs and metastasis. High attenuation on arterial phase, presence of enlarged LNs with larger size and greater number, and wash-in/wash-out enhancement pattern of liver metastasis can be useful CT discriminators of PD-NETs from ADCs. (orig.)

  6. A Sequential, Implicit, Wavelet-Based Solver for Multi-Scale Time-Dependent Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Donald A. McLaren

    2013-04-01

    Full Text Available This paper describes and tests a wavelet-based implicit numerical method for solving partial differential equations. Intended for problems with localized small-scale interactions, the method exploits the form of the wavelet decomposition to divide the implicit system created by the time-discretization into multiple smaller systems that can be solved sequentially. Included is a test on a basic non-linear problem, with both the results of the test, and the time required to calculate them, compared with control results based on a single system with fine resolution. The method is then tested on a non-trivial problem, its computational time and accuracy checked against control results. In both tests, it was found that the method requires less computational expense than the control. Furthermore, the method showed convergence towards the fine resolution control results.

  7. On geometric approach to Lie symmetries of differential-difference equations

    International Nuclear Information System (INIS)

    Li Hongjing; Wang Dengshan; Wang Shikun; Wu Ke; Zhao Weizhong

    2008-01-01

    Based upon Cartan's geometric formulation of differential equations, Harrison and Estabrook proposed a geometric approach for the symmetries of differential equations. In this Letter, we extend Harrison and Estabrook's approach to analyze the symmetries of differential-difference equations. The discrete exterior differential technique is applied in our approach. The Lie symmetry of (2+1)-dimensional Toda equation is investigated by means of our approach

  8. Parameter-free bearing fault detection based on maximum likelihood estimation and differentiation

    International Nuclear Information System (INIS)

    Bozchalooi, I Soltani; Liang, Ming

    2009-01-01

    Bearing faults can lead to malfunction and ultimately complete stall of many machines. The conventional high-frequency resonance (HFR) method has been commonly used for bearing fault detection. However, it is often very difficult to obtain and calibrate bandpass filter parameters, i.e. the center frequency and bandwidth, the key to the success of the HFR method. This inevitably undermines the usefulness of the conventional HFR technique. To avoid such difficulties, we propose parameter-free, versatile yet straightforward techniques to detect bearing faults. We focus on two types of measured signals frequently encountered in practice: (1) a mixture of impulsive faulty bearing vibrations and intrinsic background noise and (2) impulsive faulty bearing vibrations blended with intrinsic background noise and vibration interferences. To design a proper signal processing technique for each case, we analyze the effects of intrinsic background noise and vibration interferences on amplitude demodulation. For the first case, a maximum likelihood-based fault detection method is proposed to accommodate the Rician distribution of the amplitude-demodulated signal mixture. For the second case, we first illustrate that the high-amplitude low-frequency vibration interferences can make the amplitude demodulation ineffective. Then we propose a differentiation method to enhance the fault detectability. It is shown that the iterative application of a differentiation step can boost the relative strength of the impulsive faulty bearing signal component with respect to the vibration interferences. This preserves the effectiveness of amplitude demodulation and hence leads to more accurate fault detection. The proposed approaches are evaluated on simulated signals and experimental data acquired from faulty bearings

  9. The Effect of Teaching Geometry Which is Differentiated Based on the Parallel Curriculum for Gifted/Talented Students on Spatial Ability

    Directory of Open Access Journals (Sweden)

    Basak KOK

    2014-06-01

    Full Text Available The purpose of this research is to evaluate the effects of teaching geometry which is differentiated based on the parallel curriculum for gifted/talented students on spatial ability. For this purpose; two units as “Polygons” and “Geometric Objects” of 5th grade mathematics book has been taken and formed a new differentiated geometry unit. In this study, pretest and posttest designs of experimental model were used. The study was conducted in Istanbul Science and Art Center, which offers differentiated program to those who are gifted and talented students after school, in the city of İstanbul and participants were 30 students being 15 of them are experimental group and the other 15 are control group. Experimental group students were underwent a differentiated program on “Polygons” and “Geometric Objects” whereas the other group continued their normal program without any differentiation. Spatial Ability Test developed by Talented Youth Center of John Hopkins University was used to collect data. Above mentioned test was presented to both groups of the study. Collected data was analyzed by Mann Whitney-U and Wilcoxon Signed Rank Test which is in the statistics program. It is presented as a result of the study that the program prepared for the gifted and talented students raised their spatial thinking ability.

  10. Differentiating between light and deep sleep stages using an ambulatory device based on peripheral arterial tonometry

    International Nuclear Information System (INIS)

    Bresler, Ma'ayan; Sheffy, Koby; Preiszler, Meir; Herscovici, Sarah; Pillar, Giora

    2008-01-01

    The objective of this study is to develop and assess an automatic algorithm based on the peripheral arterial tone (PAT) signal to differentiate between light and deep sleep stages. The PAT signal is a measure of the pulsatile arterial volume changes at the finger tip reflecting sympathetic tone variations and is recorded by an ambulatory unattended device, the Watch-PAT100, which has been shown to be capable of detecting wake, NREM and REM sleep. An algorithm to differentiate light from deep sleep was developed using a training set of 49 patients and was validated using a separate set of 44 patients. In both patient sets, Watch-PAT100 data were recorded simultaneously with polysomnography during a full night sleep study. The algorithm is based on 14 features extracted from two time series of PAT amplitudes and inter-pulse periods (IPP). Those features were then further processed to yield a prediction function that determines the likelihood of detecting a deep sleep stage epoch during NREM sleep periods. Overall sensitivity, specificity and agreement of the automatic algorithm to identify standard 30 s epochs of light and deep sleep stages were 66%, 89%, 82% and 65%, 87%, 80% for the training and validation sets, respectively. Together with the already existing algorithms for REM and wake detection we propose a close to full stage detection method based solely on the PAT and actigraphy signals. The automatic sleep stages detection algorithm could be very useful for unattended ambulatory sleep monitoring assessing sleep stages when EEG recordings are not available

  11. International Conference on Differential and Difference Equations with Applications

    CERN Document Server

    Došlá, Zuzana; Došlý, Ondrej; Kloeden, Peter

    2016-01-01

    Aimed at the community of mathematicians working on ordinary and partial differential equations, difference equations, and functional equations, this book contains selected papers based on the presentations at the International Conference on Differential and Difference Equations and Applications (ICDDEA) 2015, dedicated to the memory of Professor Georg Sell. Contributions include new trends in the field of differential and difference equations, applications of differential and difference equations, as well as high-level survey results. The main aim of this recurring conference series is to promote, encourage, cooperate, and bring together researchers in the fields of differential and difference equations. All areas of differential and difference equations are represented, with special emphasis on applications.

  12. A Novel Method to Identify Differential Pathways in Hippocampus Alzheimer's Disease.

    Science.gov (United States)

    Liu, Chun-Han; Liu, Lian

    2017-05-08

    BACKGROUND Alzheimer's disease (AD) is the most common type of dementia. The objective of this paper is to propose a novel method to identify differential pathways in hippocampus AD. MATERIAL AND METHODS We proposed a combined method by merging existed methods. Firstly, pathways were identified by four known methods (DAVID, the neaGUI package, the pathway-based co-expressed method, and the pathway network approach), and differential pathways were evaluated through setting weight thresholds. Subsequently, we combined all pathways by a rank-based algorithm and called the method the combined method. Finally, common differential pathways across two or more of five methods were selected. RESULTS Pathways obtained from different methods were also different. The combined method obtained 1639 pathways and 596 differential pathways, which included all pathways gained from the four existing methods; hence, the novel method solved the problem of inconsistent results. Besides, a total of 13 common pathways were identified, such as metabolism, immune system, and cell cycle. CONCLUSIONS We have proposed a novel method by combining four existing methods based on a rank product algorithm, and identified 13 significant differential pathways based on it. These differential pathways might provide insight into treatment and diagnosis of hippocampus AD.

  13. Theoretical and Empirical Analyses of an Improved Harmony Search Algorithm Based on Differential Mutation Operator

    Directory of Open Access Journals (Sweden)

    Longquan Yong

    2012-01-01

    Full Text Available Harmony search (HS method is an emerging metaheuristic optimization algorithm. In this paper, an improved harmony search method based on differential mutation operator (IHSDE is proposed to deal with the optimization problems. Since the population diversity plays an important role in the behavior of evolution algorithm, the aim of this paper is to calculate the expected population mean and variance of IHSDE from theoretical viewpoint. Numerical results, compared with the HSDE, NGHS, show that the IHSDE method has good convergence property over a test-suite of well-known benchmark functions.

  14. Differential calculus and its applications

    CERN Document Server

    Field, Michael J

    2013-01-01

    Based on undergraduate courses in advanced calculus, the treatment covers a wide range of topics, from soft functional analysis and finite-dimensional linear algebra to differential equations on submanifolds of Euclidean space. 1976 edition.

  15. On functional bases of the first-order differential invariants for non-conjugate subgroups of the Poincaré group $P(1,4$

    Directory of Open Access Journals (Sweden)

    V.M. Fedorchuk

    2008-11-01

    Full Text Available It is established which functional bases of the first-order differential invariants of the splitting and non-splitting subgroups of the Poincaré group $P(1,4$ are invariant under the subgroups of the extended Galilei group $widetilde G(1,3 subset P(1,4$. The obtained sets of functional bases are classified according to dimensions.

  16. Lagrangian Differentiation, Integration and Eigenvalues Problems

    International Nuclear Information System (INIS)

    Durand, L.

    1983-01-01

    Calogero recently proposed a new and very powerful method for the solution of Sturm-Liouville eigenvalue problems based on Lagrangian differentiation. In this paper, some results of a numerical investigation of Calogero's method for physical interesting problems are presented. It is then shown that one can 'invert' his differentiation technique to obtain a flexible, factorially convergent Lagrangian integration scheme which should be useful in a variety of problems, e.g. solution of integral equations

  17. Targeted mass spektrometry based assay for monitoring neuronal differentiation

    Czech Academy of Sciences Publication Activity Database

    Žižková, Martina; Suchá, Rita; Rákocyová, Michaela; Doležalová, D.; Červenka, Jakub; Kovářová, Hana

    2015-01-01

    Roč. 78, Suppl 2 (2015), s. 26-27 ISSN 1210-7859. [Conference on Animal Models for neurodegenerative Diseases /3./. 08.11.2015-10.11.2015, Liblice] R&D Projects: GA TA ČR(CZ) TA01011466; GA MŠk ED2.1.00/03.0124; GA MŠk(CZ) 7F14308 Institutional support: RVO:67985904 Keywords : pluripotent cells * neural differentiation * neurons

  18. Value-based differential pricing: efficient prices for drugs in a global context.

    Science.gov (United States)

    Danzon, Patricia; Towse, Adrian; Mestre-Ferrandiz, Jorge

    2015-03-01

    This paper analyzes pharmaceutical pricing between and within countries to achieve second-best static and dynamic efficiency. We distinguish countries with and without universal insurance, because insurance undermines patients' price sensitivity, potentially leading to prices above second-best efficient levels. In countries with universal insurance, if each payer unilaterally sets an incremental cost-effectiveness ratio (ICER) threshold based on its citizens' willingness-to-pay for health; manufacturers price to that ICER threshold; and payers limit reimbursement to patients for whom a drug is cost-effective at that price and ICER, then the resulting price levels and use within each country and price differentials across countries are roughly consistent with second-best static and dynamic efficiency. These value-based prices are expected to differ cross-nationally with per capita income and be broadly consistent with Ramsey optimal prices. Countries without comprehensive insurance avoid its distorting effects on prices but also lack financial protection and affordability for the poor. Improving pricing efficiency in these self-pay countries includes improving regulation and consumer information about product quality and enabling firms to price discriminate within and between countries. © 2013 The Authors. Health Economics published by John Wiley & Sons Ltd.

  19. Multi-objective optimum design of fast tool servo based on improved differential evolution algorithm

    International Nuclear Information System (INIS)

    Zhu, Zhiwei; Zhou, Xiaoqin; Liu, Qiang; Zhao, Shaoxin

    2011-01-01

    The flexure-based mechanism is a promising realization of fast tool servo (FTS), and the optimum determination of flexure hinge parameters is one of the most important elements in the FTS design. This paper presents a multi-objective optimization approach to optimizing the dimension and position parameters of the flexure-based mechanism, which is based on the improved differential evolution algorithm embedding chaos and nonlinear simulated anneal algorithm. The results of optimum design show that the proposed algorithm has excellent performance and a well-balanced compromise is made between two conflicting objectives, the stroke and natural frequency of the FTS mechanism. The validation tests based on finite element analysis (FEA) show good agreement with the results obtained by using the proposed theoretical algorithm of this paper. Finally, a series of experimental tests are conducted to validate the design process and assess the performance of the FTS mechanism. The designed FTS reaches up to a stroke of 10.25 μm with at least 2 kHz bandwidth. Both of the FEA and experimental results demonstrate that the parameters of the flexure-based mechanism determined by the proposed approaches can achieve the specified performance and the proposed approach is suitable for the optimum design of FTS mechanism and of excellent performances

  20. Differential Laser Doppler based Non-Contact Sensor for Dimensional Inspection with Error Propagation Evaluation

    Directory of Open Access Journals (Sweden)

    Ketsaya Vacharanukul

    2006-06-01

    Full Text Available To achieve dynamic error compensation in CNC machine tools, a non-contactlaser probe capable of dimensional measurement of a workpiece while it is being machinedhas been developed and presented in this paper. The measurements are automatically fedback to the machine controller for intelligent error compensations. Based on a well resolvedlaser Doppler technique and real time data acquisition, the probe delivers a very promisingdimensional accuracy at few microns over a range of 100 mm. The developed opticalmeasuring apparatus employs a differential laser Doppler arrangement allowing acquisitionof information from the workpiece surface. In addition, the measurements are traceable tostandards of frequency allowing higher precision.

  1. Photon Differential Splatting for Rendering Caustics

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall; Schjøth, Lars; Erleben, Kenny

    2014-01-01

    We present a photon splatting technique which reduces noise and blur in the rendering of caustics. Blurring of illumination edges is an inherent problem in photon splatting, as each photon is unaware of its neighbours when being splatted. This means that the splat size is usually based...... on heuristics rather than knowledge of the local flux density. We use photon differentials to determine the size and shape of the splats such that we achieve adaptive anisotropic flux density estimation in photon splatting. As compared to previous work that uses photon differentials, we present the first method...... where no photons or beams or differentials need to be stored in a map. We also present improvements in the theory of photon differentials, which give more accurate results and a faster implementation. Our technique has good potential for GPU acceleration, and we limit the number of parameters requiring...

  2. Electronic differential control of 2WD electric vehicle considering steering stability

    Science.gov (United States)

    Hua, Yiding; Jiang, Haobin; Geng, Guoqing

    2017-03-01

    Aiming at the steering wheel differential steering control technology of rear wheel independent driving electric wheel, considering the assisting effect of electronic differential control on vehicle steering, based on the high speed steering characteristic of electric wheel car, the electronic differential speed of auxiliary wheel steering is also studied. A yaw moment control strategy is applied to the vehicle at high speed. Based on the vehicle stability reference value, yaw rate is used to design the fuzzy controller to distribute the driving wheel torque. The simulation results show that the basic electronic differential speed function is realized based on the yaw moment control strategy, while the vehicle stability control is improved and the driving safety is enhanced. On the other hand, the torque control strategy can also assist steering of vehicle.

  3. Arithmetic differential equations on $GL_n$, I: differential cocycles

    OpenAIRE

    Buium, Alexandru; Dupuy, Taylor

    2013-01-01

    The theory of differential equations has an arithmetic analogue in which derivatives are replaced by Fermat quotients. One can then ask what is the arithmetic analogue of a linear differential equation. The study of usual linear differential equations is the same as the study of the differential cocycle from $GL_n$ into its Lie algebra given by the logarithmic derivative. However we prove here that there are no such cocycles in the context of arithmetic differential equations. In sequels of t...

  4. Partial differential equation-based approach for empirical mode decomposition: application on image analysis.

    Science.gov (United States)

    Niang, Oumar; Thioune, Abdoulaye; El Gueirea, Mouhamed Cheikh; Deléchelle, Eric; Lemoine, Jacques

    2012-09-01

    The major problem with the empirical mode decomposition (EMD) algorithm is its lack of a theoretical framework. So, it is difficult to characterize and evaluate this approach. In this paper, we propose, in the 2-D case, the use of an alternative implementation to the algorithmic definition of the so-called "sifting process" used in the original Huang's EMD method. This approach, especially based on partial differential equations (PDEs), was presented by Niang in previous works, in 2005 and 2007, and relies on a nonlinear diffusion-based filtering process to solve the mean envelope estimation problem. In the 1-D case, the efficiency of the PDE-based method, compared to the original EMD algorithmic version, was also illustrated in a recent paper. Recently, several 2-D extensions of the EMD method have been proposed. Despite some effort, 2-D versions for EMD appear poorly performing and are very time consuming. So in this paper, an extension to the 2-D space of the PDE-based approach is extensively described. This approach has been applied in cases of both signal and image decomposition. The obtained results confirm the usefulness of the new PDE-based sifting process for the decomposition of various kinds of data. Some results have been provided in the case of image decomposition. The effectiveness of the approach encourages its use in a number of signal and image applications such as denoising, detrending, or texture analysis.

  5. Cloud computing task scheduling strategy based on improved differential evolution algorithm

    Science.gov (United States)

    Ge, Junwei; He, Qian; Fang, Yiqiu

    2017-04-01

    In order to optimize the cloud computing task scheduling scheme, an improved differential evolution algorithm for cloud computing task scheduling is proposed. Firstly, the cloud computing task scheduling model, according to the model of the fitness function, and then used improved optimization calculation of the fitness function of the evolutionary algorithm, according to the evolution of generation of dynamic selection strategy through dynamic mutation strategy to ensure the global and local search ability. The performance test experiment was carried out in the CloudSim simulation platform, the experimental results show that the improved differential evolution algorithm can reduce the cloud computing task execution time and user cost saving, good implementation of the optimal scheduling of cloud computing tasks.

  6. Pre-buckling responses of Timoshenko nanobeams based on the integral and differential models of nonlocal elasticity: an isogeometric approach

    Science.gov (United States)

    Norouzzadeh, A.; Ansari, R.; Rouhi, H.

    2017-05-01

    Differential form of Eringen's nonlocal elasticity theory is widely employed to capture the small-scale effects on the behavior of nanostructures. However, paradoxical results are obtained via the differential nonlocal constitutive relations in some cases such as in the vibration and bending analysis of cantilevers, and recourse must be made to the integral (original) form of Eringen's theory. Motivated by this consideration, a novel nonlocal formulation is developed herein based on the original formulation of Eringen's theory to study the buckling behavior of nanobeams. The governing equations are derived according to the Timoshenko beam theory, and are represented in a suitable vector-matrix form which is applicable to the finite-element analysis. In addition, an isogeometric analysis (IGA) is conducted for the solution of buckling problem. Construction of exact geometry using non-uniform rational B-splines and easy implementation of geometry refinement tools are the main advantages of IGA. A comparison study is performed between the predictions of integral and differential nonlocal models for nanobeams under different kinds of end conditions.

  7. Application of Legendre spectral-collocation method to delay differential and stochastic delay differential equation

    Science.gov (United States)

    Khan, Sami Ullah; Ali, Ishtiaq

    2018-03-01

    Explicit solutions to delay differential equation (DDE) and stochastic delay differential equation (SDDE) can rarely be obtained, therefore numerical methods are adopted to solve these DDE and SDDE. While on the other hand due to unstable nature of both DDE and SDDE numerical solutions are also not straight forward and required more attention. In this study, we derive an efficient numerical scheme for DDE and SDDE based on Legendre spectral-collocation method, which proved to be numerical methods that can significantly speed up the computation. The method transforms the given differential equation into a matrix equation by means of Legendre collocation points which correspond to a system of algebraic equations with unknown Legendre coefficients. The efficiency of the proposed method is confirmed by some numerical examples. We found that our numerical technique has a very good agreement with other methods with less computational effort.

  8. Differential sensor in front photopyroelectric technique: II. Experimental

    International Nuclear Information System (INIS)

    Ivanov, R; Moreno, I; Araujo-Andrade, C; MarIn, E; Cruz-Orea, A; Pichardo-Molina, J L

    2009-01-01

    We describe the differential cell design and the experimental (optical and electronic) setup for the differential front photopyroelectric technique, whose theory has been developed in the first part of this paper (Ivanov et al 2008 J. Phys. D: Appl. Phys. 41 085106). We will show first how the direct (non-differential) front photopyroelectric theory described in our previous paper reproduces well the experimental results. The usefulness of the differential technique is demonstrated by means of experimental measurements of the thermal effusivity in binary ethanol-water and glycerol-water mixtures, based on a theoretical methodology that simplifies the measurement procedure and diminishes the experimental uncertainty.

  9. Differential sensor in front photopyroelectric technique: II. Experimental

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, R; Moreno, I; Araujo-Andrade, C [Facultad de Fisica, Universidad Autonoma de Zacatecas, Calz. Solidaridad Esquina Paseo de la Bufa s/n, CP 98060, Zacatecas, Zac. (Mexico); MarIn, E [Centro de Investigacion en Ciencia Aplicada y TecnologIa Avanzada-Instituto Politecnico Nacional, Legaria 694, Col. Irrigacion, CP 11500, Mexico D.F. (Mexico); Cruz-Orea, A [Departamento de Fisica, CINVESTAV-IPN, Av. IPN No. 2508, Col. San Pedro Zacatenco, CP 07360, Mexico D.F. (Mexico); Pichardo-Molina, J L, E-mail: rumen@fisica.uaz.edu.m [Centro de Investigaciones en Optica, Loma del Bosque 115, Loma del Campestre, CP 37150, Leon, Guanajuato (Mexico)

    2009-06-21

    We describe the differential cell design and the experimental (optical and electronic) setup for the differential front photopyroelectric technique, whose theory has been developed in the first part of this paper (Ivanov et al 2008 J. Phys. D: Appl. Phys. 41 085106). We will show first how the direct (non-differential) front photopyroelectric theory described in our previous paper reproduces well the experimental results. The usefulness of the differential technique is demonstrated by means of experimental measurements of the thermal effusivity in binary ethanol-water and glycerol-water mixtures, based on a theoretical methodology that simplifies the measurement procedure and diminishes the experimental uncertainty.

  10. Series expansion in fractional calculus and fractional differential equations

    OpenAIRE

    Li, Ming-Fan; Ren, Ji-Rong; Zhu, Tao

    2009-01-01

    Fractional calculus is the calculus of differentiation and integration of non-integer orders. In a recently paper (Annals of Physics 323 (2008) 2756-2778), the Fundamental Theorem of Fractional Calculus is highlighted. Based on this theorem, in this paper we introduce fractional series expansion method to fractional calculus. We define a kind of fractional Taylor series of an infinitely fractionally-differentiable function. Further, based on our definition we generalize hypergeometric functio...

  11. Distinguishing Differential Testlet Functioning from Differential Bundle Functioning Using the Multilevel Measurement Model

    Science.gov (United States)

    Beretvas, S. Natasha; Walker, Cindy M.

    2012-01-01

    This study extends the multilevel measurement model to handle testlet-based dependencies. A flexible two-level testlet response model (the MMMT-2 model) for dichotomous items is introduced that permits assessment of differential testlet functioning (DTLF). A distinction is made between this study's conceptualization of DTLF and that of…

  12. Logistic discriminant parametric mapping: a novel method for the pixel-based differential diagnosis of Parkinson's disease

    International Nuclear Information System (INIS)

    Acton, P.D.; Mozley, P.D.; Kung, H.F.; Pennsylvania Univ., Philadelphia, PA

    1999-01-01

    Positron emission tomography (PET) and single-photon emission tomography (SPET) imaging of the dopaminergic system is a powerful tool for distinguishing groups of patients with neurodegenerative disorders, such as Parkinson's disease (PD). However, the differential diagnosis of individual subjects presenting early in the progress of the disease is much more difficult, particularly using region-of-interest analysis where small localized differences between subjects are diluted. In this paper we present a novel pixel-based technique using logistic discriminant analysis to distinguish between a group of PD patients and age-matched healthy controls. Simulated images of an anthropomorphic head phantom were used to test the sensitivity of the technique to striatal lesions of known size. The methodology was applied to real clinical SPET images of binding of technetium-99m labelled TRODAT-1 to dopamine transporters in PD patients (n=42) and age-matched controls (n=23). The discriminant model was trained on a subset (n=17) of patients for whom the diagnosis was unequivocal. Logistic discriminant parametric maps were obtained for all subjects, showing the probability distribution of pixels classified as being consistent with PD. The probability maps were corrected for correlated multiple comparisons assuming an isotropic Gaussian point spread function. Simulated lesion sizes measured by logistic discriminant parametric mapping (LDPM) gave strong correlations with the known data (r 2 =0.985, P<0.001). LDPM correctly classified all PD patients (sensitivity 100%) and only misclassified one control (specificity 95%). All patients who had equivocal clinical symptoms associated with early onset PD (n=4) were correctly assigned to the patient group. Statistical parametric mapping (SPM) had a sensitivity of only 24% on the same patient group. LDPM is a powerful pixel-based tool for the differential diagnosis of patients with PD and healthy controls. The diagnosis of disease even

  13. High Weak Order Methods for Stochastic Differential Equations Based on Modified Equations

    KAUST Repository

    Abdulle, Assyr

    2012-01-01

    © 2012 Society for Industrial and Applied Mathematics. Inspired by recent advances in the theory of modified differential equations, we propose a new methodology for constructing numerical integrators with high weak order for the time integration of stochastic differential equations. This approach is illustrated with the constructions of new methods of weak order two, in particular, semi-implicit integrators well suited for stiff (meansquare stable) stochastic problems, and implicit integrators that exactly conserve all quadratic first integrals of a stochastic dynamical system. Numerical examples confirm the theoretical results and show the versatility of our methodology.

  14. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATEMATICA based packages for differential reduction of generalized hypergeometric functions. F{sub D} and F{sub S} Horn-type hypergeometric functions of three variables

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Kalmykov, Mikhail Yu. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Moch, Sven-Olaf [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-12-15

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: the first one, FdFunction, for manipulations with Appell hypergeometric functions F{sub D} of r variables; and the second one, FsFunction, for manipulations with Lauricella-Saran hypergeometric functions F{sub S} of three variables. Both functions are related with one-loop Feynman diagrams.

  15. A chaotic modulation scheme based on algebraic observability and sliding mode differentiators

    International Nuclear Information System (INIS)

    Cannas, Barbara; Cincotti, Silvano; Usai, Elio

    2005-01-01

    A chaotic communication technique for the transmission of secure information signals is presented. The proposed method allows the reconstruction of the system input (i.e., the information signal) from a scalar observable (i.e., the transmitted signal) and its derivatives. The approach is based on the concept of algebraic observability. A systematic procedure for the chaotic demodulation of the class of algebraic chaotic systems is described and discussed. The proposed procedure also allows one to directly identify a suitable 'response' system and the 'drive signal'. Moreover, it is shown that sliding differentiators can be used to reconstruct the time derivatives of the observable, and thus the information signal is recovered at the receiving end through some simple signal-processing operations such as multiplication, addition and subtraction. This allows the estimation of the system state and of the input signal (i.e., the information recovery) in a finite time

  16. A rank-based algorithm of differential expression analysis for small cell line data with statistical control.

    Science.gov (United States)

    Li, Xiangyu; Cai, Hao; Wang, Xianlong; Ao, Lu; Guo, You; He, Jun; Gu, Yunyan; Qi, Lishuang; Guan, Qingzhou; Lin, Xu; Guo, Zheng

    2017-10-13

    To detect differentially expressed genes (DEGs) in small-scale cell line experiments, usually with only two or three technical replicates for each state, the commonly used statistical methods such as significance analysis of microarrays (SAM), limma and RankProd (RP) lack statistical power, while the fold change method lacks any statistical control. In this study, we demonstrated that the within-sample relative expression orderings (REOs) of gene pairs were highly stable among technical replicates of a cell line but often widely disrupted after certain treatments such like gene knockdown, gene transfection and drug treatment. Based on this finding, we customized the RankComp algorithm, previously designed for individualized differential expression analysis through REO comparison, to identify DEGs with certain statistical control for small-scale cell line data. In both simulated and real data, the new algorithm, named CellComp, exhibited high precision with much higher sensitivity than the original RankComp, SAM, limma and RP methods. Therefore, CellComp provides an efficient tool for analyzing small-scale cell line data. © The Author 2017. Published by Oxford University Press.

  17. NMR-based lipidomic analysis of blood lipoproteins differentiates the progression of coronary heart disease.

    Science.gov (United States)

    Kostara, Christina E; Papathanasiou, Athanasios; Psychogios, Nikolaos; Cung, Manh Thong; Elisaf, Moses S; Goudevenos, John; Bairaktari, Eleni T

    2014-05-02

    Abnormal lipid composition and metabolism of plasma lipoproteins play a crucial role in the pathogenesis of coronary heart disease (CHD). A (1)H NMR-based lipidomic approach was used to investigate the correlation of coronary artery stenosis with the atherogenic (non-HDL) and atheroprotective (HDL) lipid profiles in 99 patients with CHD of various stages of disease and compared with 60 patients with normal coronary arteries (NCA), all documented in coronary angiography. The pattern recognition models created from lipid profiles predicted the presence of CHD with a sensitivity of 87% and a specificity of 88% in the HDL model and with 90% and 89% in the non-HDL model, respectively. Patients with mild, moderate, and severe coronary artery stenosis were progressively differentiated from those with NCA in the non-HDL model with a statistically significant separation of severe stage from both mild and moderate. In the HDL model, the progressive differentiation of the disease stages was statistically significant only between patients with mild and severe coronary artery stenosis. The lipid constituents of lipoproteins that mainly characterized the initial stages and then the progression of the disease were the high levels of saturated fatty acids in lipids in both HDL and non-HDL particles, the low levels of HDL-phosphatidylcholine, HDL-sphingomyelin, and omega-3 fatty acids and linoleic acid in lipids in non-HDL particles. The conventional lipid marker, total cholesterol, found in low levels in HDL and in high levels in non-HDL, also contributed to the onset of the disease but with a much lower coefficient of significance. (1)H NMR-based lipidomic analysis of atherogenic and atheroprotective lipoproteins could contribute to the early evaluation of the onset of coronary artery disease and possibly to the establishment of an appropriate therapeutic option.

  18. A general comparison theorem for backward stochastic differential equations

    OpenAIRE

    Cohen, Samuel N.; Elliott, Robert J.; Pearce, Charles E. M.

    2010-01-01

    A useful result when dealing with backward stochastic differential equations is the comparison theorem of Peng (1992). When the equations are not based on Brownian motion, the comparison theorem no longer holds in general. In this paper we present a condition for a comparison theorem to hold for backward stochastic differential equations based on arbitrary martingales. This theorem applies to both vector and scalar situations. Applications to the theory of nonlinear expectat...

  19. Diagnostic of the temperature and differential emission measure (DEM based on Hinode/XRT data

    Directory of Open Access Journals (Sweden)

    P. Rudawy

    2008-10-01

    Full Text Available We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present the determination of the temperature distribution of the X-rays emitting plasma using a filters ratio method and three various methods of the calculation of the differential emission measure (DEM. We have found that all these methods give results similar to the two filters ratio method. Additionally, all methods of the DEM calculation gave similar solutions. We can state that the majority of the pairs of the Hinode filters allows one to derive the temperature and emission measure in the isothermal plasma approximation using standard diagnostics based on the two filters ratio method. In cases of strong flares one can also expect good conformity of the results obtained using a Withbroe – Sylwester, genetic algorithm and least-squares methods of the DEM evaluation.

  20. CT differentiation of poorly-differentiated gastric neuroendocrine tumours from well-differentiated neuroendocrine tumours and gastric adenocarcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Ho; Kim, Se Hyung; Shin, Cheong-il; Han, Joon Koo; Choi, Byung Ihn [Seoul National University Hospital, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Seoul National University Hospital, Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of); Kim, Min-A [Seoul National University Hospital, Department of Pathology, Jongno-gu, Seoul (Korea, Republic of)

    2015-07-15

    To evaluate the differential CT features of gastric poorly-differentiated neuroendocrine tumours (PD-NETs) from well-differentiated NETs (WD-NETs) and gastric adenocarcinomas (ADCs) and to suggest differential features of hepatic metastases from gastric NETs and ADCs. Our study population was comprised of 36 patients with gastric NETs (18 WD-NETs, 18 PD-NETs) and 38 patients with gastric ADCs who served as our control group. Multiple CT features were assessed to identify significant differential CT findings of PD-NETs from WD-NETs and ADCs. In addition, CT features of hepatic metastases including the metastasis-to-liver ratio were analyzed to differentiate metastatic NETs from ADCs. The presence of metastatic lymph nodes was the sole differentiator of PD-NETs from WD-NETs (P =.001, odds ratio = 56.67), while the presence of intact overlying mucosa with mucosal tenting was the sole significant CT feature differentiating PD-NETs from ADCs (P =.047, odds ratio = 15.3) For hepatic metastases, metastases from NETs were more hyper-attenuated than those from ADCs. The presence of metastatic LNs and intact overlying mucosa with mucosal tenting are useful CT discriminators of PD-NETs from WD-NETs and ADCs, respectively. In addition, a higher metastasis-to-liver ratio may help differentiate hepatic metastases of gastric NETs from those of gastric ADCs with high accuracy. (orig.)

  1. Differential Raytracing for special illumination systems; Differentielles Raytracing fuer spezielle Beleuchtungssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Stolz, Oliver

    2010-02-19

    Differential ray tracing is implemented into the optics design software RAYTRACE and its performance is compared to Monte Carlo calculations. Simulations of illumination systems show that differential ray tracing yields smooth and noiseless results in (mostly) much smaller computational time as compared to the Monte Carlo simulations. Both shape and absolute values of the intensity distributions are in good agreement. When calculating with the differential method instead of using the Monte Carlo method one could, depending on the optical setup, save up to a tenfold of time. In optical systems containing lens arrays, the speed advantage of the differential ray tracing method slightly decreases. This is because the differential approach generates ray groups and calculates the total intensity distribution as the superposition of the separately interpolated distributions of each group. Another main focus of this work was the development of an improved optimization algorithm for optical illumination systems and in particular also for refractive beam-shaping elements which are based on free-form surfaces. The optimization aim is coded into a mathematical expression, the so called ''merit function''. Contrary to the merit function based on the Monte-Carlo ray tracing technique, a new merit function based on differential ray tracing is derived. As the differential approach works noiseless the resulting merit function excels through a smooth and continuous form. Comparative calculations between deterministic (e.g. gradient methods) and stochastical optimization techniques (e.g. Monte-Carlo method, simulated annealing, evolutionary algorithms, particle swarm optimization) are presented for both types of merit functions. It is shown that combinations of differential ray tracing with modern population-based optimization methods, like the evolutionary algorithms and the particle swarm optimization can achieve an actual reduction of computational time while

  2. Reduced minimax filtering by means of differential-algebraic equations

    NARCIS (Netherlands)

    V. Mallet; S. Zhuk (Sergiy)

    2011-01-01

    htmlabstractA reduced minimax state estimation approach is proposed for high-dimensional models. It is based on the reduction of the ordinary differential equation with high state space dimension to the low-dimensional Differential-Algebraic Equation (DAE) and on the subsequent application of the

  3. Label-free morphology-based prediction of multiple differentiation potentials of human mesenchymal stem cells for early evaluation of intact cells.

    Directory of Open Access Journals (Sweden)

    Hiroto Sasaki

    Full Text Available Precise quantification of cellular potential of stem cells, such as human bone marrow-derived mesenchymal stem cells (hBMSCs, is important for achieving stable and effective outcomes in clinical stem cell therapy. Here, we report a method for image-based prediction of the multiple differentiation potentials of hBMSCs. This method has four major advantages: (1 the cells used for potential prediction are fully intact, and therefore directly usable for clinical applications; (2 predictions of potentials are generated before differentiation cultures are initiated; (3 prediction of multiple potentials can be provided simultaneously for each sample; and (4 predictions of potentials yield quantitative values that correlate strongly with the experimental data. Our results show that the collapse of hBMSC differentiation potentials, triggered by in vitro expansion, can be quantitatively predicted far in advance by predicting multiple potentials, multi-lineage differentiation potentials (osteogenic, adipogenic, and chondrogenic and population doubling potential using morphological features apparent during the first 4 days of expansion culture. In order to understand how such morphological features can be effective for advance predictions, we measured gene-expression profiles of the same early undifferentiated cells. Both senescence-related genes (p16 and p21 and cytoskeleton-related genes (PTK2, CD146, and CD49 already correlated to the decrease of potentials at this stage. To objectively compare the performance of morphology and gene expression for such early prediction, we tested a range of models using various combinations of features. Such comparison of predictive performances revealed that morphological features performed better overall than gene-expression profiles, balancing the predictive accuracy with the effort required for model construction. This benchmark list of various prediction models not only identifies the best morphological feature

  4. International conference Fourier Analysis and Pseudo-Differential Operators

    CERN Document Server

    Turunen, Ville; Fourier Analysis : Pseudo-differential Operators, Time-Frequency Analysis and Partial Differential Equations

    2014-01-01

    This book is devoted to the broad field of Fourier analysis and its applications to several areas of mathematics, including problems in the theory of pseudo-differential operators, partial differential equations, and time-frequency analysis. This collection of 20 refereed articles is based on selected talks given at the international conference “Fourier Analysis and Pseudo-Differential Operators,” June 25–30, 2012, at Aalto University, Finland, and presents the latest advances in the field. The conference was a satellite meeting of the 6th European Congress of Mathematics, which took place in Krakow in July 2012; it was also the 6th meeting in the series “Fourier Analysis and Partial Differential Equations.”

  5. Introduction to fractional and pseudo-differential equations with singular symbols

    CERN Document Server

    Umarov, Sabir

    2015-01-01

    The book systematically presents the theories of pseudo-differential operators with symbols singular in dual variables, fractional order derivatives, distributed and variable order fractional derivatives, random walk approximants, and applications of these theories to various initial and multi-point boundary value problems for pseudo-differential equations. Fractional Fokker-Planck-Kolmogorov equations associated with a large class of stochastic processes are presented. A complex version of the theory of pseudo-differential operators with meromorphic symbols based on the recently introduced complex Fourier transform is developed and applied for initial and boundary value problems for systems of complex differential and pseudo-differential equations.

  6. Surgical management of metastatic differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Fakih, A.R.; Mistry, R.C.

    1999-01-01

    The differentiated management of metastatic differentiated thyroid cancer (DTC) with lymph node and/or systemic metastases is very much a treatable cancer. Interaction between the surgeon and the nuclear medicine specialist is essential to ensure quality survival in these patient. This review is confined to surgical aspects and is based on experience with 417 patients who were operated for DTC at the Tata Memorial Hospital between 1971 and 1985

  7. Male rock sparrows differentially allocate nest defence but not food provisioning to offspring

    DEFF Research Database (Denmark)

    Matessi, Giuliano; Carmagnani, Cristina; Griggio, Matteo

    2009-01-01

    for a number of species, while male differential allocation based on female secondary sexual traits has received less attention. Yet females of many species, among birds in particular, are ornamented. We performed a test of male differential allocation based on a female ornament in the rock sparrow (Petronia...... allocation and are in agreement with previous tests of male differential allocation in rock sparrows....

  8. Differential transimpedance amplifier circuit for correlated differential amplification

    Science.gov (United States)

    Gresham, Christopher A [Albuquerque, NM; Denton, M Bonner [Tucson, AZ; Sperline, Roger P [Tucson, AZ

    2008-07-22

    A differential transimpedance amplifier circuit for correlated differential amplification. The amplifier circuit increase electronic signal-to-noise ratios in charge detection circuits designed for the detection of very small quantities of electrical charge and/or very weak electromagnetic waves. A differential, integrating capacitive transimpedance amplifier integrated circuit comprising capacitor feedback loops performs time-correlated subtraction of noise.

  9. Differential evolution algorithm based automatic generation control for interconnected power systems with

    Directory of Open Access Journals (Sweden)

    Banaja Mohanty

    2014-09-01

    Full Text Available This paper presents the design and performance analysis of Differential Evolution (DE algorithm based Proportional–Integral (PI and Proportional–Integral–Derivative (PID controllers for Automatic Generation Control (AGC of an interconnected power system. Initially, a two area thermal system with governor dead-band nonlinearity is considered for the design and analysis purpose. In the proposed approach, the design problem is formulated as an optimization problem control and DE is employed to search for optimal controller parameters. Three different objective functions are used for the design purpose. The superiority of the proposed approach has been shown by comparing the results with a recently published Craziness based Particle Swarm Optimization (CPSO technique for the same interconnected power system. It is noticed that, the dynamic performance of DE optimized PI controller is better than CPSO optimized PI controllers. Additionally, controller parameters are tuned at different loading conditions so that an adaptive gain scheduling control strategy can be employed. The study is further extended to a more realistic network of two-area six unit system with different power generating units such as thermal, hydro, wind and diesel generating units considering boiler dynamics for thermal plants, Generation Rate Constraint (GRC and Governor Dead Band (GDB non-linearity.

  10. Differential equations

    CERN Document Server

    Barbu, Viorel

    2016-01-01

    This textbook is a comprehensive treatment of ordinary differential equations, concisely presenting basic and essential results in a rigorous manner. Including various examples from physics, mechanics, natural sciences, engineering and automatic theory, Differential Equations is a bridge between the abstract theory of differential equations and applied systems theory. Particular attention is given to the existence and uniqueness of the Cauchy problem, linear differential systems, stability theory and applications to first-order partial differential equations. Upper undergraduate students and researchers in applied mathematics and systems theory with a background in advanced calculus will find this book particularly useful. Supplementary topics are covered in an appendix enabling the book to be completely self-contained.

  11. Numerical discretization-based estimation methods for ordinary differential equation models via penalized spline smoothing with applications in biomedical research.

    Science.gov (United States)

    Wu, Hulin; Xue, Hongqi; Kumar, Arun

    2012-06-01

    Differential equations are extensively used for modeling dynamics of physical processes in many scientific fields such as engineering, physics, and biomedical sciences. Parameter estimation of differential equation models is a challenging problem because of high computational cost and high-dimensional parameter space. In this article, we propose a novel class of methods for estimating parameters in ordinary differential equation (ODE) models, which is motivated by HIV dynamics modeling. The new methods exploit the form of numerical discretization algorithms for an ODE solver to formulate estimating equations. First, a penalized-spline approach is employed to estimate the state variables and the estimated state variables are then plugged in a discretization formula of an ODE solver to obtain the ODE parameter estimates via a regression approach. We consider three different order of discretization methods, Euler's method, trapezoidal rule, and Runge-Kutta method. A higher-order numerical algorithm reduces numerical error in the approximation of the derivative, which produces a more accurate estimate, but its computational cost is higher. To balance the computational cost and estimation accuracy, we demonstrate, via simulation studies, that the trapezoidal discretization-based estimate is the best and is recommended for practical use. The asymptotic properties for the proposed numerical discretization-based estimators are established. Comparisons between the proposed methods and existing methods show a clear benefit of the proposed methods in regards to the trade-off between computational cost and estimation accuracy. We apply the proposed methods t an HIV study to further illustrate the usefulness of the proposed approaches. © 2012, The International Biometric Society.

  12. Trajectory Evaluation of Rotor-Flying Robots Using Accurate Inverse Computation Based on Algorithm Differentiation

    Directory of Open Access Journals (Sweden)

    Yuqing He

    2014-01-01

    Full Text Available Autonomous maneuvering flight control of rotor-flying robots (RFR is a challenging problem due to the highly complicated structure of its model and significant uncertainties regarding many aspects of the field. As a consequence, it is difficult in many cases to decide whether or not a flight maneuver trajectory is feasible. It is necessary to conduct an analysis of the flight maneuvering ability of an RFR prior to test flight. Our aim in this paper is to use a numerical method called algorithm differentiation (AD to solve this problem. The basic idea is to compute the internal state (i.e., attitude angles and angular rates and input profiles based on predetermined maneuvering trajectory information denoted by the outputs (i.e., positions and yaw angle and their higher-order derivatives. For this purpose, we first present a model of the RFR system and show that it is flat. We then cast the procedure for obtaining the required state/input based on the desired outputs as a static optimization problem, which is solved using AD and a derivative based optimization algorithm. Finally, we test our proposed method using a flight maneuver trajectory to verify its performance.

  13. Comparison of DNA-based techniques for differentiation of production strains of ale and lager brewing yeast.

    Science.gov (United States)

    Kopecká, J; Němec, M; Matoulková, D

    2016-06-01

    Brewing yeasts are classified into two species-Saccharomyces pastorianus and Saccharomyces cerevisiae. Most of the brewing yeast strains are natural interspecies hybrids typically polyploids and their identification is thus often difficult giving heterogenous results according to the method used. We performed genetic characterization of a set of the brewing yeast strains coming from several yeast culture collections by combination of various DNA-based techniques. The aim of this study was to select a method for species-specific identification of yeast and discrimination of yeast strains according to their technological classification. A group of 40 yeast strains were characterized using PCR-RFLP analysis of ITS-5·8S, NTS, HIS4 and COX2 genes, multiplex PCR, RAPD-PCR of genomic DNA, mtDNA-RFLP and electrophoretic karyotyping. Reliable differentiation of yeast to the species level was achieved by PCR-RFLP of HIS4 gene. Numerical analysis of the obtained RAPD-fingerprints and karyotype revealed species-specific clustering corresponding with the technological classification of the strains. Taxonomic position and partial hybrid nature of strains were verified by multiplex PCR. Differentiation among species using the PCR-RFLP of ITS-5·8S and NTS region was shown to be unreliable. Karyotyping and RFLP of mitochondrial DNA evinced small inaccuracies in strain categorization. PCR-RFLP of HIS4 gene and RAPD-PCR of genomic DNA are reliable and suitable methods for fast identification of yeast strains. RAPD-PCR with primer 21 is a fast and reliable method applicable for differentiation of brewing yeasts with only 35% similarity of fingerprint profile between the two main technological groups (ale and lager) of brewing strains. It was proved that PCR-RFLP method of HIS4 gene enables precise discrimination among three technologically important Saccharomyces species. Differentiation of brewing yeast to the strain level can be achieved using the RAPD-PCR technique. © 2016 The

  14. The radiological and histopathological differential diagnosis of chordoid neoplasms in skull base

    Directory of Open Access Journals (Sweden)

    PAN Bin-cai

    2013-07-01

    Full Text Available Background Chordoid neoplasms refer to tumors appearing to have histological features of embryonic notochord, which is characterized by cords and lobules of neoplastic cells arranged within myxoid matrix. Because of radiological and histological similarities with myxoid matrix and overlapping immunohistochemical profile, chordoma, chordoid meningioma, chordoid glioma, and rare extraskeletal myxoid chondrosarcoma enter in the radiological and histological differential diagnosis at the site of skull base. However, there is always a great challenge for histopathologists to make an accurate diagnosis when encountering a chordoid neoplasm within or near the central nervous system. The aim of this study is to investigate and summarize the radiological, histological features and immunohistochemical profiles of chordoid neoplasms in skull base, and to find a judicious panel of immunostains to unquestionably help in diagnostically challenging cases. Methods A total of 23 cases of chordoid neoplasms in skull base, including 10 chordomas, 5 chordoid meningiomas, 3 chordoid gliomas and 5 extraskeletal myxoid chondrosarcomas, were collected from the First Affiliated Hospital, Sun Yat-sen University and Guangdong Tongjiang Hospital. MRI examination was performed on the patients before surgical treatment. Microscopical examination and immunohistochemical staining study using vimentin (Vim, pan-cytokeratin (PCK, epithelial membrane antigen (EMA, S?100 protein (S-100, glial fibrillary acidic protein (GFAP, D2-40, Galectin-3, CD3, CD20, Ki-67 were performed on the samples of cases. The clinicopathological data of the patients was also analyzed retrospectively. Results Most of chordomas were localized in the clivus with heterogeneous hyperintensity on T2WI scanning. The breakage of clivus was observed in most cases. Histologically, the tumor cells of chordoma exhibited bland nuclear features and some contained abundant vacuolated cytoplasm (the so

  15. Energy-Based Yield Criteria for Orthotropic Materials, Exhibiting Strength-Differential Effect. Specification for Sheets under Plane Stress State

    Directory of Open Access Journals (Sweden)

    Szeptyński P.

    2017-06-01

    Full Text Available A general proposition of an energy-based limit condition for anisotropic materials exhibiting strength-differential effect (SDE based on spectral decomposition of elasticity tensors and the use of scaling pressure-dependent functions is specified for the case of orthotropic materials. A detailed algorithm (based on classical solutions of cubic equations for the determination of elastic eigenstates and eigenvalues of the orthotropic stiffness tensor is presented. A yield condition is formulated for both two-dimensional and three-dimensional cases. Explicit formulas based on simple strength tests are derived for parameters of criterion in the plane case. The application of both criteria for the description of yielding and plastic deformation of metal sheets is discussed in detail. The plane case criterion is verified with experimental results from the literature.

  16. Two-dimensional block-based reception for differentially encoded OFDM systems : a study on improved reception techniques for digital audio broadcasting systems

    NARCIS (Netherlands)

    Houtum, van W.J.

    2012-01-01

    Digital audio broadcast (DAB), DAB+ and Terrestrial-Digital Multimedia Broadcasting (T-DMB) systems use multi-carrier modulation (MCM). The principle of MCM in the DAB-family is based on orthogonal frequency division multiplexing (OFDM), for which every subcarrier is modulated by p 4 differentially

  17. Automatic differentiation bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, G.F. [comp.

    1992-07-01

    This is a bibliography of work related to automatic differentiation. Automatic differentiation is a technique for the fast, accurate propagation of derivative values using the chain rule. It is neither symbolic nor numeric. Automatic differentiation is a fundamental tool for scientific computation, with applications in optimization, nonlinear equations, nonlinear least squares approximation, stiff ordinary differential equation, partial differential equations, continuation methods, and sensitivity analysis. This report is an updated version of the bibliography which originally appeared in Automatic Differentiation of Algorithms: Theory, Implementation, and Application.

  18. Edge detection of optical subaperture image based on improved differential box-counting method

    Science.gov (United States)

    Li, Yi; Hui, Mei; Liu, Ming; Dong, Liquan; Kong, Lingqin; Zhao, Yuejin

    2018-01-01

    Optical synthetic aperture imaging technology is an effective approach to improve imaging resolution. Compared with monolithic mirror system, the image of optical synthetic aperture system is often more complex at the edge, and as a result of the existence of gap between segments, which makes stitching becomes a difficult problem. So it is necessary to extract the edge of subaperture image for achieving effective stitching. Fractal dimension as a measure feature can describe image surface texture characteristics, which provides a new approach for edge detection. In our research, an improved differential box-counting method is used to calculate fractal dimension of image, then the obtained fractal dimension is mapped to grayscale image to detect edges. Compared with original differential box-counting method, this method has two improvements as follows: by modifying the box-counting mechanism, a box with a fixed height is replaced by a box with adaptive height, which solves the problem of over-counting the number of boxes covering image intensity surface; an image reconstruction method based on super-resolution convolutional neural network is used to enlarge small size image, which can solve the problem that fractal dimension can't be calculated accurately under the small size image, and this method may well maintain scale invariability of fractal dimension. The experimental results show that the proposed algorithm can effectively eliminate noise and has a lower false detection rate compared with the traditional edge detection algorithms. In addition, this algorithm can maintain the integrity and continuity of image edge in the case of retaining important edge information.

  19. Astragalus-containing Traditional Chinese Medicine, with and without prescription based on syndrome differentiation, combined with chemotherapy for advanced non-small-cell lung cancer: a systemic review and meta-analysis.

    Science.gov (United States)

    Wang, S F; Wang, Q; Jiao, L J; Huang, Y L; Garfield, D; Zhang, J; Xu, L

    2016-06-01

    Traditional Chinese Medicine (tcm) is used in China as part of the treatment for non-small-cell lung cancer (nsclc) and often includes prescription of herbal therapy based on syndrome differentiation. Studies of various Astragalus-based Chinese medicines combined with platinum-based chemotherapy in the treatment of lung cancer are popular in East Asia, particularly in China. The aim of the present study was to perform a systematic review and meta-analysis comparing platinum-based chemotherapy alone with platinum-based chemotherapy plus Astragalus-based Chinese botanicals, with and without prescription based on syndrome differentiation, as first-line treatment for advanced nsclc. We searched the Chinese Biomedical Literature database, the China National Knowledge Internet, the VIP Chinese Science and Technology Periodicals Database, PubMed, embase, the Cochrane databases, and abstracts presented at meetings of the American Society of Clinical Oncology, the World Conference on Lung Cancer, the European Society for Medical Oncology, and the Chinese Society of Clinical Oncology for all eligible studies. Endpoints were overall survival; 1-year, 2-year, and 3-year survival rates; performance status; overall response rate; and grade 3 or 4 adverse events. Subgroup analyses based on herbal formulae individualized using syndrome differentiation or on oral or injection patent medicines were performed using the Stata software application (version 11.0: StataCorp LP, College Station, TX, U.S.A.) and a fixed-effects or random-effects model in case of heterogeneity. Results are expressed as a hazard ratio (hr) or relative risk (rr), with corresponding 95% confidence intervals (cis). Seventeen randomized studies with scores on the Jadad quality scale of 2 or more, representing 1552 patients, met the inclusion criteria. Compared with platinum-based chemotherapy alone, the addition of Astragalus-based tcm to chemotherapy was associated with significantly increased overall survival

  20. Monitoring inter-channel nonlinearity based on differential pilot

    Science.gov (United States)

    Wang, Wanli; Yang, Aiying; Guo, Peng; Lu, Yueming; Qiao, Yaojun

    2018-06-01

    We modify and simplify the inter-channel nonlinearity (NL) estimation method by using differential pilot. Compared to previous works, the inter-channel NL estimation method we propose has much lower complexity and does not need modification of the transmitter. The performance of inter-channel NL monitoring with different launch power is tested. For both QPSK and 16QAM systems with 9 channels, the estimation error of inter-channel NL is lower than 1 dB when the total launch power is bigger than 12 dBm after 1000 km optical transmission. At last, we compare our inter-channel NL estimation method with other methods.

  1. Differential Performance by English Language Learners on an Inquiry-Based Science Assessment

    Science.gov (United States)

    Turkan, Sultan; Liu, Ou Lydia

    2012-10-01

    The performance of English language learners (ELLs) has been a concern given the rapidly changing demographics in US K-12 education. This study aimed to examine whether students' English language status has an impact on their inquiry science performance. Differential item functioning (DIF) analysis was conducted with regard to ELL status on an inquiry-based science assessment, using a multifaceted Rasch DIF model. A total of 1,396 seventh- and eighth-grade students took the science test, including 313 ELL students. The results showed that, overall, non-ELLs significantly outperformed ELLs. Of the four items that showed DIF, three favored non-ELLs while one favored ELLs. The item that favored ELLs provided a graphic representation of a science concept within a family context. There is some evidence that constructed-response items may help ELLs articulate scientific reasoning using their own words. Assessment developers and teachers should pay attention to the possible interaction between linguistic challenges and science content when designing assessment for and providing instruction to ELLs.

  2. Analysis of RDSS positioning accuracy based on RNSS wide area differential technique

    Science.gov (United States)

    Xing, Nan; Su, RanRan; Zhou, JianHua; Hu, XiaoGong; Gong, XiuQiang; Liu, Li; He, Feng; Guo, Rui; Ren, Hui; Hu, GuangMing; Zhang, Lei

    2013-10-01

    The BeiDou Navigation Satellite System (BDS) provides Radio Navigation Service System (RNSS) as well as Radio Determination Service System (RDSS). RDSS users can obtain positioning by responding the Master Control Center (MCC) inquiries to signal transmitted via GEO satellite transponder. The positioning result can be calculated with elevation constraint by MCC. The primary error sources affecting the RDSS positioning accuracy are the RDSS signal transceiver delay, atmospheric trans-mission delay and GEO satellite position error. During GEO orbit maneuver, poor orbit forecast accuracy significantly impacts RDSS services. A real-time 3-D orbital correction method based on wide-area differential technique is raised to correct the orbital error. Results from the observation shows that the method can successfully improve positioning precision during orbital maneuver, independent from the RDSS reference station. This improvement can reach 50% in maximum. Accurate calibration of the RDSS signal transceiver delay precision and digital elevation map may have a critical role in high precise RDSS positioning services.

  3. Clustering gene expression data based on predicted differential effects of GV interaction.

    Science.gov (United States)

    Pan, Hai-Yan; Zhu, Jun; Han, Dan-Fu

    2005-02-01

    Microarray has become a popular biotechnology in biological and medical research. However, systematic and stochastic variabilities in microarray data are expected and unavoidable, resulting in the problem that the raw measurements have inherent "noise" within microarray experiments. Currently, logarithmic ratios are usually analyzed by various clustering methods directly, which may introduce bias interpretation in identifying groups of genes or samples. In this paper, a statistical method based on mixed model approaches was proposed for microarray data cluster analysis. The underlying rationale of this method is to partition the observed total gene expression level into various variations caused by different factors using an ANOVA model, and to predict the differential effects of GV (gene by variety) interaction using the adjusted unbiased prediction (AUP) method. The predicted GV interaction effects can then be used as the inputs of cluster analysis. We illustrated the application of our method with a gene expression dataset and elucidated the utility of our approach using an external validation.

  4. Brachyury, SOX-9, and Podoplanin, New Markers in the Skull Base Chordoma Vs Chondrosarcoma Differential: A Tissue Microarray Based Comparative Analysis

    Science.gov (United States)

    Oakley, GJ; Fuhrer, K; Seethala, RR

    2014-01-01

    The distinction between chondrosarcoma and chordoma of the skull base/head and neck is prognostically important; however, both have sufficient morphologic overlap to make distinction difficult. As a result of gene expression studies, additional candidate markers have been proposed to help in this distinction. Hence, we sought to evaluate the performance of new markers: brachyury, SOX-9, and podoplanin alongside the more traditional markers glial fibrillary acid protein, carcinoembryonic antigen, CD24 and epithelial membrane antigen. Paraffin blocks from 103 skull base/head and neck chondroid tumors from 70 patients were retrieved (1969-2007). Diagnoses were made based on morphology and/or whole section immunohistochemistry for cytokeratin and S100 protein yielding 79 chordomas (comprising 45 chondroid chordomas and 34 conventional chordomas), and 24 chondrosarcomas. A tissue microarray containing 0.6 mm cores of each tumor in triplicate was constructed using a manual array (MTA-1, Beecher Instruments). For visualization of staining, the ImmPRESS detection system (Vector Laboratories) with 2 - diaminobenzidine substrate was used. Sensitivities and specificities were calculated for each marker. Core loss from the microarray ranged from 25-29% yielding 66-78 viable cases per stain. The classic marker, cytokeratin, still has the best performance characteristics. When combined with brachyury, accuracy improves slightly (sensitivity and specificity for detection of chordoma 98% and 100%, respectively). Positivity for both epithelial membrane antigen and AE1/AE3 had a sensitivity of 90% and a specificity of 100% for detecting chordoma in this study. SOX-9 is apparently common to both notochordal and cartilaginous differentiation, and is not useful in the chordoma-chondrosarcoma differential diagnosis. Glial fibrillary acid protein, carcinoembryonic antigen, CD24, and epithelial membrane antigen did not outperform other markers, and are less useful in the diagnosis of

  5. Differential manifolds

    CERN Document Server

    Kosinski, Antoni A

    2007-01-01

    The concepts of differential topology form the center of many mathematical disciplines such as differential geometry and Lie group theory. Differential Manifolds presents to advanced undergraduates and graduate students the systematic study of the topological structure of smooth manifolds. Author Antoni A. Kosinski, Professor Emeritus of Mathematics at Rutgers University, offers an accessible approach to both the h-cobordism theorem and the classification of differential structures on spheres.""How useful it is,"" noted the Bulletin of the American Mathematical Society, ""to have a single, sho

  6. Nielsen number and differential equations

    Directory of Open Access Journals (Sweden)

    Andres Jan

    2005-01-01

    Full Text Available In reply to a problem of Jean Leray (application of the Nielsen theory to differential equations, two main approaches are presented. The first is via Poincaré's translation operator, while the second one is based on the Hammerstein-type solution operator. The applicability of various Nielsen theories is discussed with respect to several sorts of differential equations and inclusions. Links with the Sharkovskii-like theorems (a finite number of periodic solutions imply infinitely many subharmonics are indicated, jointly with some further consequences like the nontrivial -structure of solutions of initial value problems. Some illustrating examples are supplied and open problems are formulated.

  7. Differential equations

    CERN Document Server

    Tricomi, FG

    2013-01-01

    Based on his extensive experience as an educator, F. G. Tricomi wrote this practical and concise teaching text to offer a clear idea of the problems and methods of the theory of differential equations. The treatment is geared toward advanced undergraduates and graduate students and addresses only questions that can be resolved with rigor and simplicity.Starting with a consideration of the existence and uniqueness theorem, the text advances to the behavior of the characteristics of a first-order equation, boundary problems for second-order linear equations, asymptotic methods, and diff

  8. Insomnia Phenotypes Based on Objective Sleep Duration in Adolescents: Depression Risk and Differential Behavioral Profiles

    Directory of Open Access Journals (Sweden)

    Julio Fernandez-Mendoza

    2016-12-01

    Full Text Available Based on previous studies on the role of objective sleep duration in predicting morbidity in individuals with insomnia, we examined the role of objective sleep duration in differentiating behavioral profiles in adolescents with insomnia symptoms. Adolescents from the Penn State Child Cohort (n = 397, ages 12–23, 54.7% male underwent a nine-hour polysomnography (PSG, clinical history, physical examination and psychometric testing, including the Child or Adult Behavior Checklist and Pediatric Behavior Scale. Insomnia symptoms were defined as a self-report of difficulty falling and/or staying asleep and objective “short” sleep duration as a PSG total sleep time ≤7 h. A significant interaction showed that objective short sleep duration modified the association of insomnia symptoms with internalizing problems. Consistently, adolescents with insomnia symptoms and short sleep duration were characterized by depression, rumination, mood dysregulation and social isolation, while adolescents with insomnia symptoms and normal sleep duration were characterized by rule-breaking and aggressive behaviors and, to a lesser extent, rumination. These findings indicate that objective sleep duration is useful in differentiating behavioral profiles among adolescents with insomnia symptoms. The insomnia with objective short sleep duration phenotype is associated with an increased risk of depression earlier in the lifespan than previously believed.

  9. Inference for High-dimensional Differential Correlation Matrices.

    Science.gov (United States)

    Cai, T Tony; Zhang, Anru

    2016-01-01

    Motivated by differential co-expression analysis in genomics, we consider in this paper estimation and testing of high-dimensional differential correlation matrices. An adaptive thresholding procedure is introduced and theoretical guarantees are given. Minimax rate of convergence is established and the proposed estimator is shown to be adaptively rate-optimal over collections of paired correlation matrices with approximately sparse differences. Simulation results show that the procedure significantly outperforms two other natural methods that are based on separate estimation of the individual correlation matrices. The procedure is also illustrated through an analysis of a breast cancer dataset, which provides evidence at the gene co-expression level that several genes, of which a subset has been previously verified, are associated with the breast cancer. Hypothesis testing on the differential correlation matrices is also considered. A test, which is particularly well suited for testing against sparse alternatives, is introduced. In addition, other related problems, including estimation of a single sparse correlation matrix, estimation of the differential covariance matrices, and estimation of the differential cross-correlation matrices, are also discussed.

  10. Multimedia applications in differential services

    International Nuclear Information System (INIS)

    Mahfooz, S.; Merabti, M.; Pereira, R.

    2003-01-01

    In this paper we present a mechanism to provide Quality of Service (QoS) guarantees to different multimedia applications that share link bandwidth in IP-based differential services domain. In this mechanism weights are associated with each and to individual users according to their priorities. In order to evaluate the performance of our scheme we conducted simulations. The test data used portray different multimedia applications i.e. MPEG-2, IP telephony. The simulation results obtained show the effectiveness of our scheme for multimedia applications by allocating link share to each multimedia application and minimising end-to-end transmission delay 9Y bringing them in line with the recommended standard acceptable transmission delay for multimedia applications. This paper also presents extension to our proposed Relative Bandwidth Sharing (RES) scheme for differential services. We have identified and highlighted the role of border routers and core routers in differential services domain. Exploring features of Internet Protocol IPv6 in our architecture. (author)

  11. Differentiering i Undervisningen på Universitetet

    DEFF Research Database (Denmark)

    Jensen, Christine Revsbech; Pedersen, Ulf Rørbæk

    Through a historical and literature based investigation of the term ‘teaching differentiation’ we discuss and investigate the question: “What is teaching differentiation in university education and how and when do we differentiate during the programs that we teach respectively?” The uncovering...... of the term is followed by two course examples from quantum physics and the international summer supplementation course. The courses are very different in nature, content, and placement in the different programs. We reflect on the examples separately followed by a general discussion of our findings. Our......, that student learning logs and study progress descriptions advantageously could be expanded with elements that help the student gain insight into and navigate in own learning strategies based on the particular learning environments on RUC, between courses and peer-learning....

  12. Undergraduate Students' Mental Operations in Systems of Differential Equations

    Science.gov (United States)

    Whitehead, Karen; Rasmussen, Chris

    2003-01-01

    This paper reports on research conducted to understand undergraduate students' ways of reasoning about systems of differential equations (SDEs). As part of a semester long classroom teaching experiment in a first course in differential equations, we conducted task-based interviews with six students after their study of first order differential…

  13. A meshless scheme for partial differential equations based on multiquadric trigonometric B-spline quasi-interpolation

    International Nuclear Information System (INIS)

    Gao Wen-Wu; Wang Zhi-Gang

    2014-01-01

    Based on the multiquadric trigonometric B-spline quasi-interpolant, this paper proposes a meshless scheme for some partial differential equations whose solutions are periodic with respect to the spatial variable. This scheme takes into account the periodicity of the analytic solution by using derivatives of a periodic quasi-interpolant (multiquadric trigonometric B-spline quasi-interpolant) to approximate the spatial derivatives of the equations. Thus, it overcomes the difficulties of the previous schemes based on quasi-interpolation (requiring some additional boundary conditions and yielding unwanted high-order discontinuous points at the boundaries in the spatial domain). Moreover, the scheme also overcomes the difficulty of the meshless collocation methods (i.e., yielding a notorious ill-conditioned linear system of equations for large collocation points). The numerical examples that are presented at the end of the paper show that the scheme provides excellent approximations to the analytic solutions. (general)

  14. Gröbner Bases and Generation of Difference Schemes for Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Vladimir P. Gerdt

    2006-05-01

    Full Text Available In this paper we present an algorithmic approach to the generation of fully conservative difference schemes for linear partial differential equations. The approach is based on enlargement of the equations in their integral conservation law form by extra integral relations between unknown functions and their derivatives, and on discretization of the obtained system. The structure of the discrete system depends on numerical approximation methods for the integrals occurring in the enlarged system. As a result of the discretization, a system of linear polynomial difference equations is derived for the unknown functions and their partial derivatives. A difference scheme is constructed by elimination of all the partial derivatives. The elimination can be achieved by selecting a proper elimination ranking and by computing a Gröbner basis of the linear difference ideal generated by the polynomials in the discrete system. For these purposes we use the difference form of Janet-like Gröbner bases and their implementation in Maple. As illustration of the described methods and algorithms, we construct a number of difference schemes for Burgers and Falkowich-Karman equations and discuss their numerical properties.

  15. Differential geometry of group lattices

    International Nuclear Information System (INIS)

    Dimakis, Aristophanes; Mueller-Hoissen, Folkert

    2003-01-01

    In a series of publications we developed ''differential geometry'' on discrete sets based on concepts of noncommutative geometry. In particular, it turned out that first-order differential calculi (over the algebra of functions) on a discrete set are in bijective correspondence with digraph structures where the vertices are given by the elements of the set. A particular class of digraphs are Cayley graphs, also known as group lattices. They are determined by a discrete group G and a finite subset S. There is a distinguished subclass of ''bicovariant'' Cayley graphs with the property ad(S)S subset of S. We explore the properties of differential calculi which arise from Cayley graphs via the above correspondence. The first-order calculi extend to higher orders and then allow us to introduce further differential geometric structures. Furthermore, we explore the properties of ''discrete'' vector fields which describe deterministic flows on group lattices. A Lie derivative with respect to a discrete vector field and an inner product with forms is defined. The Lie-Cartan identity then holds on all forms for a certain subclass of discrete vector fields. We develop elements of gauge theory and construct an analog of the lattice gauge theory (Yang-Mills) action on an arbitrary group lattice. Also linear connections are considered and a simple geometric interpretation of the torsion is established. By taking a quotient with respect to some subgroup of the discrete group, generalized differential calculi associated with so-called Schreier diagrams are obtained

  16. Asymptotic integration of differential and difference equations

    CERN Document Server

    Bodine, Sigrun

    2015-01-01

    This book presents the theory of asymptotic integration for both linear differential and difference equations. This type of asymptotic analysis is based on some fundamental principles by Norman Levinson. While he applied them to a special class of differential equations, subsequent work has shown that the same principles lead to asymptotic results for much wider classes of differential and also difference equations. After discussing asymptotic integration in a unified approach, this book studies how the application of these methods provides several new insights and frequent improvements to results found in earlier literature. It then continues with a brief introduction to the relatively new field of asymptotic integration for dynamic equations on time scales. Asymptotic Integration of Differential and Difference Equations is a self-contained and clearly structured presentation of some of the most important results in asymptotic integration and the techniques used in this field. It will appeal to researchers i...

  17. A non-correlator-based digital communication system using interleaved chaotic differential peaks keying (I-CDPK) modulation and chaotic synchronization

    International Nuclear Information System (INIS)

    Chien, T.-I; Hung, Y.-C.; Liao, T.-L.

    2006-01-01

    This paper presents a novel non-correlator-based digital communication system with the application of interleaved chaotic differential peaks keying (I-CDPK) modulation technique. The proposed communication system consists of four major modules: I-CDPK modulator (ICM), frequency modulation (FM) transmitter, FM receiver and I-CDPK demodulator (ICDM). In the ICM module, there are four components: a chaotic circuit to generate the chaotic signals, A/D converter, D/A converter and a digital processing mechanism to control all signal flows and performs I-CDPK modulation corresponding to the input digital bits. For interleaving every input digital bit set, every state of the chaotic system is used to represent one portion of it, but only a scalar state variable (i.e. the system output) is sent to the ICDM's chaotic circuit through both FM transmitter and FM receiver. An observer-based chaotic synchronization scheme is designed to synchronize the chaotic circuits of the ICM and ICDM. Meanwhile, the bit detector in ICDM is devoted to recover the transmitted input digital bits. Some numerical simulations of an illustrative communication system are given to demonstrate its theoretical effectiveness. Furthermore, the performance of bit error rate of the proposed system is analyzed and compared with those of the correlator-based communication systems adopting coherent binary phase shift keying (BPSK) and coherent differential chaotic shift keying (DCSK) schemes

  18. Experiments with a Differential Transformer

    Science.gov (United States)

    Aguilar, Horacio Munguía

    2016-01-01

    An experiment with an electric transformer based on single coils shows how electromagnetic induction changes when the magnetic coupling between coils is adjusted. This transformer has two secondary outputs which are taken differentially. This is the basis for a widely used position transducer known as LVDT.

  19. Polytetrafluorethylene film-based liquid-three phase micro extraction coupled with differential pulse voltammetry for the determination of atorvastatin calcium.

    Science.gov (United States)

    Ensafi, Ali A; Khoddami, Elaheh; Rezaei, Behzad

    2013-01-01

    In this paper, we describe a new combination method based on polytetrafluorethylene (PTFE) film-based liquid three-phase micro extraction coupled with differential pulse voltammetry (DPV) for the micro extraction and quantification of atorvastatin calcium (ATC) at the ultra-trace level. Different factors affecting the liquid-three phases micro extraction of atorvastatin calcium, including organic solvent, pH of the donor and acceptor phases, concentration of salt, extraction time, stirring rate and electrochemical factors, were investigated, and the optimal extraction conditions were established. The final stable signal was achieved after a 50 min extraction time, which was used for analytical applications. An enrichment factor of 21 was achieved, and the relative standard deviation (RSD) of the method was 4.5% (n = 4). Differential pulse voltammetry exhibited two wide linear dynamic ranges of 20.0-1000.0 pmol L(-1) and 0.001-11.0 µmol L(-1) of ATC. The detection limit was found to be 8.1 pmol L(-1) ATC. Finally, the proposed method was used as a new combination method for the determination of atorvastatin calcium in real samples, such as human urine and plasma.

  20. Rational approximations to solutions of linear differential equations.

    Science.gov (United States)

    Chudnovsky, D V; Chudnovsky, G V

    1983-08-01

    Rational approximations of Padé and Padé type to solutions of differential equations are considered. One of the main results is a theorem stating that a simultaneous approximation to arbitrary solutions of linear differential equations over C(x) cannot be "better" than trivial ones implied by the Dirichlet box principle. This constitutes, in particular, the solution in the linear case of Kolchin's problem that the "Roth's theorem" holds for arbitrary solutions of algebraic differential equations. Complete effective proofs for several valuations are presented based on the Wronskian methods and graded subrings of Picard-Vessiot extensions.

  1. Oscillation of a class of fractional differential equations with damping term.

    Science.gov (United States)

    Qin, Huizeng; Zheng, Bin

    2013-01-01

    We investigate the oscillation of a class of fractional differential equations with damping term. Based on a certain variable transformation, the fractional differential equations are converted into another differential equations of integer order with respect to the new variable. Then, using Riccati transformation, inequality, and integration average technique, some new oscillatory criteria for the equations are established. As for applications, oscillation for two certain fractional differential equations with damping term is investigated by the use of the presented results.

  2. Graphene-Based Patterning and Differentiation of C2C12 Myoblasts

    DEFF Research Database (Denmark)

    Bajaj, Piyush; Rivera, Jose A; Marchwiany, Daniel

    2014-01-01

    This study aims at generating highly aligned functional myotubes using graphene as the underlying scaffold. Graphene not only supports the growth of C2C12 muscle cells but also enhances its differentiation and leads to spontaneous patterning of myotubes....

  3. The effect of numerical techniques on differential equation based chaotic generators

    KAUST Repository

    Zidan, Mohammed A.; Radwan, Ahmed G.; Salama, Khaled N.

    2012-01-01

    In this paper, we study the effect of the numerical solution accuracy on the digital implementation of differential chaos generators. Four systems are built on a Xilinx Virtex 4 FPGA using Euler, mid-point, and Runge-Kutta fourth order techniques

  4. Experimental parameters differentially affect the humoral response of the cholera-toxin-based murine model of food allergy

    DEFF Research Database (Denmark)

    Kroghsbo, S.; Christensen, Hanne Risager; Frøkiær, Hanne

    2003-01-01

    Background: Recent studies have developed a murine model of IgE-mediated food allergy based on oral coadministration of antigen and cholera toxin (CT) to establish a maximal response for studying immunopathogenic mechanisms and immunotherapeutic strategies. However, for studying subtle...... interested in characterizing the individual effects of the parameters in the CT-based model: CT dose, antigen type and dose, and number of immunizations. Methods: BALB/c mice were orally sensitized weekly for 3 or 7 weeks with graded doses of CT and various food antigens (soy-trypsin inhibitor, ovalbumin...... of the antibody response depended on the type of antigen and number of immunizations. Conclusions: The critical parameters of the CT-based murine allergy model differentially control the intensity and kinetics of the developing immune response. Adjustment of these parameters could be a key tool for tailoring...

  5. Use of PCR-Based Methods for Rapid Differentiation of Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis

    OpenAIRE

    Torriani, Sandra; Zapparoli, Giacomo; Dellaglio, Franco

    1999-01-01

    Two PCR-based methods, specific PCR and randomly amplified polymorphic DNA PCR (RAPD-PCR), were used for rapid and reliable differentiation of Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis. PCR with a single combination of primers which targeted the proline iminopeptidase (pepIP) gene of L. delbrueckii subsp. bulgaricus allowed amplification of genomic fragments specific for the two subspecies when either DNA from a single colony or cells extracted from dairy pr...

  6. The synchronization of three fractional differential systems

    International Nuclear Information System (INIS)

    Li Changpin; Yan Jianping

    2007-01-01

    In this paper, a new method is proposed and applied to the synchronization of fractional differential systems (or 'differential systems with fractional orders'), where both drive and response systems have the same dimensionality and are coupled by the driving signal. The present technique is based on the stability criterion of linear fractional systems. This method is implemented in (chaos) synchronization of the fractional Lorenz system, Chen system and Chua circuit. Numerical simulations show the present synchronization method works well

  7. Lung Cancer Signature Biomarkers: tissue specific semantic similarity based clustering of Digital Differential Display (DDD data

    Directory of Open Access Journals (Sweden)

    Srivastava Mousami

    2012-11-01

    Full Text Available Abstract Background The tissue-specific Unigene Sets derived from more than one million expressed sequence tags (ESTs in the NCBI, GenBank database offers a platform for identifying significantly and differentially expressed tissue-specific genes by in-silico methods. Digital differential display (DDD rapidly creates transcription profiles based on EST comparisons and numerically calculates, as a fraction of the pool of ESTs, the relative sequence abundance of known and novel genes. However, the process of identifying the most likely tissue for a specific disease in which to search for candidate genes from the pool of differentially expressed genes remains difficult. Therefore, we have used ‘Gene Ontology semantic similarity score’ to measure the GO similarity between gene products of lung tissue-specific candidate genes from control (normal and disease (cancer sets. This semantic similarity score matrix based on hierarchical clustering represents in the form of a dendrogram. The dendrogram cluster stability was assessed by multiple bootstrapping. Multiple bootstrapping also computes a p-value for each cluster and corrects the bias of the bootstrap probability. Results Subsequent hierarchical clustering by the multiple bootstrapping method (α = 0.95 identified seven clusters. The comparative, as well as subtractive, approach revealed a set of 38 biomarkers comprising four distinct lung cancer signature biomarker clusters (panel 1–4. Further gene enrichment analysis of the four panels revealed that each panel represents a set of lung cancer linked metastasis diagnostic biomarkers (panel 1, chemotherapy/drug resistance biomarkers (panel 2, hypoxia regulated biomarkers (panel 3 and lung extra cellular matrix biomarkers (panel 4. Conclusions Expression analysis reveals that hypoxia induced lung cancer related biomarkers (panel 3, HIF and its modulating proteins (TGM2, CSNK1A1, CTNNA1, NAMPT/Visfatin, TNFRSF1A, ETS1, SRC-1, FN1, APLP2, DMBT1

  8. POLYMYOSITIS/DERMATOMIOSITIS: DIFFERENTIAL DIAGNOSIS

    Directory of Open Access Journals (Sweden)

    O. A. Antelava

    2016-01-01

    Full Text Available The lecture considers the problem of rare systemic connective tissue diseases, such as idiopathic inflammatory myopathies (IIMs. It underlines the clinical and immunological heterogeneity of their subtypes, which defines therapeutic tactics and prognosis. The diagnostic criteria for IIMs are given. A differential diagnostic algorithm based on the exclusion of phenotypically similar forms of myopathies of different genesis is proposed. 

  9. Sensing line effects on PWR-based differential pressure measurements

    International Nuclear Information System (INIS)

    Evans, R.P.; Neff, G.G.

    1982-01-01

    An incorrrect configuration of the fluid-filled pressure sensing lines connecting differential pressure transducers to the pressure taps in a pressurized water reactor system can cause errors in the measurement and, during rapid pressure transients, could cause the transducer to fail. Testing was performed in both static and dynamic modes to experimentally determine the effects of sensing lines of various lengths, diameters, and materials. Testing was performed at ambient temperature with absolute line pressures at about 17 MPa using water as the pressure transmission fluid

  10. Augmented nonlinear differentiator design and application to nonlinear uncertain systems.

    Science.gov (United States)

    Shao, Xingling; Liu, Jun; Li, Jie; Cao, Huiliang; Shen, Chong; Zhang, Xiaoming

    2017-03-01

    In this paper, an augmented nonlinear differentiator (AND) based on sigmoid function is developed to calculate the noise-less time derivative under noisy measurement condition. The essential philosophy of proposed AND in achieving high attenuation of noise effect is established by expanding the signal dynamics with extra state variable representing the integrated noisy measurement, then with the integral of measurement as input, the augmented differentiator is formulated to improve the estimation quality. The prominent advantages of the present differentiation technique are: (i) better noise suppression ability can be achieved without appreciable delay; (ii) the improved methodology can be readily extended to construct augmented high-order differentiator to obtain multiple derivatives. In addition, the convergence property and robustness performance against noises are investigated via singular perturbation theory and describing function method, respectively. Also, comparison with several classical differentiators is given to illustrate the superiority of AND in noise suppression. Finally, the robust control problems of nonlinear uncertain systems, including a numerical example and a mass spring system, are addressed to demonstrate the effectiveness of AND in precisely estimating the disturbance and providing the unavailable differential estimate to implement output feedback based controller. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Implementation of Wavelet-Based Robust Differential Control for Electric Vehicle Application

    DEFF Research Database (Denmark)

    Daya, Febin; Padmanaban, Sanjeevikumar; Blaabjerg, Frede

    2015-01-01

    This research letter presents the modeling and simulation of electronic differential, employing a novel wavelet controller for two brushless dc motors. The proposed controller uses discrete wavelet transform to decompose the error between actual and reference speed. Error signal that is actually...

  12. A practical course in differential equations and mathematical modeling

    CERN Document Server

    Ibragimov , Nail H

    2009-01-01

    A Practical Course in Differential Equations and Mathematical Modelling is a unique blend of the traditional methods of ordinary and partial differential equations with Lie group analysis enriched by the author's own theoretical developments. The book which aims to present new mathematical curricula based on symmetry and invariance principles is tailored to develop analytic skills and working knowledge in both classical and Lie's methods for solving linear and nonlinear equations. This approach helps to make courses in differential equations, mathematical modelling, distributions and fundame

  13. An algorithm of computing inhomogeneous differential equations for definite integrals

    OpenAIRE

    Nakayama, Hiromasa; Nishiyama, Kenta

    2010-01-01

    We give an algorithm to compute inhomogeneous differential equations for definite integrals with parameters. The algorithm is based on the integration algorithm for $D$-modules by Oaku. Main tool in the algorithm is the Gr\\"obner basis method in the ring of differential operators.

  14. The role of parental personality traits in differential parenting.

    Science.gov (United States)

    Browne, Dillon T; Meunier, Jean Christophe; O'Connor, Thomas G; Jenkins, Jennifer M

    2012-08-01

    Significant relationships have been demonstrated between parental personality and parenting toward individual children, but there is little research exploring the relationship between parental personality and differential parenting (DP). The present study examined the relationship between the Big Five personality dimensions and differential positivity and negativity in parenting (observed and self-report measures). The analyses are based on a sample of 867 children nested within 381 families. Using multilevel modeling and controlling for child age, gender, birth order, behavior, and family socioeconomic status analyses revealed that maternal and paternal agreeableness were inversely related to reports of differential positivity. Agreeableness predicted observed differential negativity, and the relationship was curvilinear (at both high and low levels of agreeableness, differential negativity was higher). Finally, mothers with the most openness to experience exhibited the highest levels of reported differential negativity. The findings suggest that parental personality is a modest yet important influence to consider when conceptualizing the sources of DP. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  15. Differential Precipitation and Solubilization of Proteins.

    Science.gov (United States)

    Ryan, Barry J; Kinsella, Gemma K

    2017-01-01

    Differential protein precipitation is a rapid and economical step in protein purification and is based on exploiting the inherent physicochemical properties of the polypeptide. Precipitation of recombinant proteins, lysed from the host cell, is commonly used to concentrate the protein of choice before further polishing steps with more selective purification columns (e.g., His-Tag, Size Exclusion, etc.). Recombinant proteins can also precipitate naturally as inclusion bodies due to various influences during overexpression in the host cell. Although this phenomenon permits easier initial separation from native proteins, these inclusion bodies must carefully be differentially solubilized so as to reform functional, correctly folded proteins. Here, appropriate bioinformatics tools to aid in understanding a protein's propensity to aggregate and solubilize are explored as a backdrop for a typical protein extraction, precipitation, and selective resolubilization procedure, based on a recombinantly expressed protein.

  16. The influence of the b-value combination on apparent diffusion coefficient based differentiation between malignant and benign tissue in cervical cancer

    NARCIS (Netherlands)

    Hoogendam, Jacob P.; Klerkx, Wenche M.; de Kort, Gerard A. P.; Bipat, Shandra; Zweemer, Ronald P.; Sie-Go, Daisy M. D. S.; Verheijen, René H. M.; Mali, Willem P. T. M.; Veldhuis, Wouter B.

    2010-01-01

    To analyze the influence of different b-value combinations on apparent diffusion coefficient (ADC)-based differentiation of known malignant and benign tissue in cervical cancer patients. A total of 35 patients with stage IB1, IB2, IIA cervical cancer underwent a 3.0T MRI scan prior to radical

  17. Partial Differential Equations Modeling and Numerical Simulation

    CERN Document Server

    Glowinski, Roland

    2008-01-01

    This book is dedicated to Olivier Pironneau. For more than 250 years partial differential equations have been clearly the most important tool available to mankind in order to understand a large variety of phenomena, natural at first and then those originating from human activity and technological development. Mechanics, physics and their engineering applications were the first to benefit from the impact of partial differential equations on modeling and design, but a little less than a century ago the Schrödinger equation was the key opening the door to the application of partial differential equations to quantum chemistry, for small atomic and molecular systems at first, but then for systems of fast growing complexity. Mathematical modeling methods based on partial differential equations form an important part of contemporary science and are widely used in engineering and scientific applications. In this book several experts in this field present their latest results and discuss trends in the numerical analy...

  18. Efficient design of FIR filter based low-pass differentiators for biomedical signal processing

    Directory of Open Access Journals (Sweden)

    Wulf Michael

    2016-09-01

    Full Text Available This paper describes an alternative design of linear phase low-pass differentiators with a finite impulse response (type III FIR filter. To reduce the number of necessary filter coefficients, the differentiator’s transfer function is approximated by a Fourier series of a triangle function. Thereby the filter’s transition steepness towards the stopband is intentionally reduced. It can be shown that the proposed design of low-pass differentiators yields to similar results as other published design recommendations, while the filter order can be significantly reduced.

  19. Differential effect of exposure-based therapy and cognitive therapy on post-traumatic stress disorder symptom clusters: A randomized controlled trial.

    Science.gov (United States)

    Horesh, Danny; Qian, Meng; Freedman, Sara; Shalev, Arieh

    2017-06-01

    A question remains regarding differential effects of exposure-based versus non-exposure-based therapies on specific post-traumatic stress disorder (PTSD) symptom clusters. Traumatized emergency room patients were randomized to receive prolonged exposure (PE) or cognitive therapy (CT) without exposure. PE/CT had no differential effect on individual symptom clusters, and change in total PTSD score remained significant even after controlling for the reductions in all three symptom clusters. In addition, baseline levels of PTSD avoidance/intrusion/hyperarousal did not moderate the effects of PE and CT on total PTSD symptom scores. Taken together, these findings challenge the notion that PE and CT are specifically, and differentially, useful in treating one particular PTSD symptom cluster. Despite their different theoretical backgrounds and techniques, the notion that PE and CT (without exposure) target different PTSD symptoms was not confirmed in this study. Thus, both interventions may in fact be equally effective for treating intrusion, avoidance and hyperarousal symptoms. Baseline levels of avoidance, intrusion and hyperarousal may not be good a priori indicators for PTSD treatment selection. The effect of PE and CT on PTSD as a whole does not seem to depend on a reduction in any specific symptom cluster. These findings indicate that exposure and non-exposure interventions may lead to similar results in terms of reductions in specific PTSD symptoms. It is quite possible that individual PTSD clusters may respond to therapy in an inter-related fashion, with one cluster affecting the other. © 2016 The British Psychological Society.

  20. Novel Differential Current Control Strategy Based on a Modified Three-Level SVPWM for Two Parallel-Connected Inverters

    DEFF Research Database (Denmark)

    Zorig, Abdelmalik; Barkat, Said; Belkheiri, Mohammed

    2017-01-01

    Recently, parallel inverters have been investigated to provide multilevel characteristics besides their advantage to increase the power system capacity, reliability, and efficiency. However, the issue of differential currents imbalance remains a challenge in parallel inverter operation. The distr......Recently, parallel inverters have been investigated to provide multilevel characteristics besides their advantage to increase the power system capacity, reliability, and efficiency. However, the issue of differential currents imbalance remains a challenge in parallel inverter operation....... The distribution of switching vectors of the resulting multilevel topology has a certain degree of self-differential current balancing properties. Nevertheless, the method alone is not sufficient to maintain balanced differential current in practical applications. This paper proposes a closed-loop differential...... current control method by introducing a control variable adjusting the dwell time of the selected switching vectors and thus maintaining the differential currents balanced without affecting the overall system performance. The control strategy, including distribution of switching sequence, selection...

  1. Sparse dynamics for partial differential equations.

    Science.gov (United States)

    Schaeffer, Hayden; Caflisch, Russel; Hauck, Cory D; Osher, Stanley

    2013-04-23

    We investigate the approximate dynamics of several differential equations when the solutions are restricted to a sparse subset of a given basis. The restriction is enforced at every time step by simply applying soft thresholding to the coefficients of the basis approximation. By reducing or compressing the information needed to represent the solution at every step, only the essential dynamics are represented. In many cases, there are natural bases derived from the differential equations, which promote sparsity. We find that our method successfully reduces the dynamics of convection equations, diffusion equations, weak shocks, and vorticity equations with high-frequency source terms.

  2. Measurements of differential and double-differential Drell-Yan cross sections in proton-proton collisions at $\\sqrt{s}$ = 8 TeV

    CERN Document Server

    Khachatryan, Vardan; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hartl, Christian; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Treberer-Treberspurg, Wolfgang; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Alderweireldt, Sara; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Knutsson, Albert; Lauwers, Jasper; Luyckx, Sten; Ochesanu, Silvia; Rougny, Romain; Van De Klundert, Merijn; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Daci, Nadir; Heracleous, Natalie; Keaveney, James; Lowette, Steven; Maes, Michael; Olbrechts, Annik; Python, Quentin; Strom, Derek; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Caillol, Cécile; Clerbaux, Barbara; De Lentdecker, Gilles; Dobur, Didar; Favart, Laurent; Gay, Arnaud; Grebenyuk, Anastasia; Léonard, Alexandre; Mohammadi, Abdollah; Perniè, Luca; Randle-conde, Aidan; Reis, Thomas; Seva, Tomislav; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Zenoni, Florian; Adler, Volker; Beernaert, Kelly; Benucci, Leonardo; Cimmino, Anna; Costantini, Silvia; Crucy, Shannon; Dildick, Sven; Fagot, Alexis; Garcia, Guillaume; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Poyraz, Deniz; Ryckbosch, Dirk; Salva Diblen, Sinem; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Beluffi, Camille; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Da Silveira, Gustavo Gil; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Jafari, Abideh; Jez, Pavel; Komm, Matthias; Lemaitre, Vincent; Nuttens, Claude; Perrini, Lucia; Pin, Arnaud; Piotrzkowski, Krzysztof; Popov, Andrey; Quertenmont, Loic; Selvaggi, Michele; Vidal Marono, Miguel; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Aldá Júnior, Walter Luiz; Alves, Gilvan; Brito, Lucas; Correa Martins Junior, Marcos; Dos Reis Martins, Thiago; Molina, Jorge; Mora Herrera, Clemencia; Pol, Maria Elena; Rebello Teles, Patricia; Carvalho, Wagner; Chinellato, Jose; Custódio, Analu; Melo Da Costa, Eliza; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santaolalla, Javier; Santoro, Alberto; Sznajder, Andre; Tonelli Manganote, Edmilson José; Vilela Pereira, Antonio; Bernardes, Cesar Augusto; Dogra, Sunil; Tomei, Thiago; De Moraes Gregores, Eduardo; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Aleksandrov, Aleksandar; Genchev, Vladimir; Hadjiiska, Roumyana; Iaydjiev, Plamen; Marinov, Andrey; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Vutova, Mariana; Dimitrov, Anton; Glushkov, Ivan; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Chen, Mingshui; Cheng, Tongguang; Du, Ran; Jiang, Chun-Hua; Plestina, Roko; Romeo, Francesco; Tao, Junquan; Wang, Zheng; Asawatangtrakuldee, Chayanit; Ban, Yong; Li, Qiang; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Wang, Dayong; Xu, Zijun; Zou, Wei; Avila, Carlos; Cabrera, Andrés; Chaparro Sierra, Luisa Fernanda; Florez, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Sudic, Lucija; Attikis, Alexandros; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Bodlak, Martin; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Ellithi Kamel, Ali; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Murumaa, Marion; Raidal, Martti; Tiko, Andres; Eerola, Paula; Voutilainen, Mikko; Härkönen, Jaakko; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Wendland, Lauri; Talvitie, Joonas; Tuuva, Tuure; Besancon, Marc; Couderc, Fabrice; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Favaro, Carlotta; Ferri, Federico; Ganjour, Serguei; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Rander, John; Rosowsky, André; Titov, Maksym; Baffioni, Stephanie; Beaudette, Florian; Busson, Philippe; Chapon, Emilien; Charlot, Claude; Dahms, Torsten; Dalchenko, Mykhailo; Dobrzynski, Ludwik; Filipovic, Nicolas; Florent, Alice; Granier de Cassagnac, Raphael; Mastrolorenzo, Luca; Miné, Philippe; Naranjo, Ivo Nicolas; Nguyen, Matthew; Ochando, Christophe; Ortona, Giacomo; Paganini, Pascal; Regnard, Simon; Salerno, Roberto; Sauvan, Jean-Baptiste; Sirois, Yves; Veelken, Christian; Yilmaz, Yetkin; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Aubin, Alexandre; Bloch, Daniel; Brom, Jean-Marie; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Goetzmann, Christophe; Le Bihan, Anne-Catherine; Skovpen, Kirill; Van Hove, Pierre; Gadrat, Sébastien; Beauceron, Stephanie; Beaupere, Nicolas; Bernet, Colin; Boudoul, Gaelle; Bouvier, Elvire; Brochet, Sébastien; Carrillo Montoya, Camilo Andres; Chasserat, Julien; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Fan, Jiawei; Fay, Jean; Gascon, Susan; Gouzevitch, Maxime; Ille, Bernard; Kurca, Tibor; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Ruiz Alvarez, José David; Sabes, David; Sgandurra, Louis; Sordini, Viola; Vander Donckt, Muriel; Verdier, Patrice; Viret, Sébastien; Xiao, Hong; Tsamalaidze, Zviad; Autermann, Christian; Beranek, Sarah; Bontenackels, Michael; Edelhoff, Matthias; Feld, Lutz; Heister, Arno; Klein, Katja; Lipinski, Martin; Ostapchuk, Andrey; Preuten, Marius; Raupach, Frank; Sammet, Jan; Schael, Stefan; Schulte, Jan-Frederik; Weber, Hendrik; Wittmer, Bruno; Zhukov, Valery; Ata, Metin; Brodski, Michael; Dietz-Laursonn, Erik; Duchardt, Deborah; Erdmann, Martin; Fischer, Robert; Güth, Andreas; Hebbeker, Thomas; Heidemann, Carsten; Hoepfner, Kerstin; Klingebiel, Dennis; Knutzen, Simon; Kreuzer, Peter; Merschmeyer, Markus; Meyer, Arnd; Millet, Philipp; Olschewski, Mark; Padeken, Klaas; Papacz, Paul; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Teyssier, Daniel; Thüer, Sebastian; Weber, Martin; Cherepanov, Vladimir; Erdogan, Yusuf; Flügge, Günter; Geenen, Heiko; Geisler, Matthias; Haj Ahmad, Wael; Hoehle, Felix; Kargoll, Bastian; Kress, Thomas; Kuessel, Yvonne; Künsken, Andreas; Lingemann, Joschka; Nowack, Andreas; Nugent, Ian Michael; Pooth, Oliver; Stahl, Achim; Aldaya Martin, Maria; Asin, Ivan; Bartosik, Nazar; Behr, Joerg; Behrens, Ulf; Bell, Alan James; Bethani, Agni; Borras, Kerstin; Burgmeier, Armin; Cakir, Altan; Calligaris, Luigi; Campbell, Alan; Choudhury, Somnath; Costanza, Francesco; Diez Pardos, Carmen; Dolinska, Ganna; Dooling, Samantha; Dorland, Tyler; Eckerlin, Guenter; Eckstein, Doris; Eichhorn, Thomas; Flucke, Gero; Garay Garcia, Jasone; Geiser, Achim; Gunnellini, Paolo; Hauk, Johannes; Hempel, Maria; Jung, Hannes; Kalogeropoulos, Alexis; Kasemann, Matthias; Katsas, Panagiotis; Kieseler, Jan; Kleinwort, Claus; Korol, Ievgen; Krücker, Dirk; Lange, Wolfgang; Leonard, Jessica; Lipka, Katerina; Lobanov, Artur; Lohmann, Wolfgang; Lutz, Benjamin; Mankel, Rainer; Marfin, Ihar; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mittag, Gregor; Mnich, Joachim; Mussgiller, Andreas; Naumann-Emme, Sebastian; Nayak, Aruna; Ntomari, Eleni; Perrey, Hanno; Pitzl, Daniel; Placakyte, Ringaile; Raspereza, Alexei; Ribeiro Cipriano, Pedro M; Roland, Benoit; Ron, Elias; Sahin, Mehmet Özgür; Salfeld-Nebgen, Jakob; Saxena, Pooja; Schoerner-Sadenius, Thomas; Schröder, Matthias; Seitz, Claudia; Spannagel, Simon; Vargas Trevino, Andrea Del Rocio; Walsh, Roberval; Wissing, Christoph; Blobel, Volker; Centis Vignali, Matteo; Draeger, Arne-Rasmus; Erfle, Joachim; Garutti, Erika; Goebel, Kristin; Görner, Martin; Haller, Johannes; Hoffmann, Malte; Höing, Rebekka Sophie; Junkes, Alexandra; Kirschenmann, Henning; Klanner, Robert; Kogler, Roman; Lange, Jörn; Lapsien, Tobias; Lenz, Teresa; Marchesini, Ivan; Ott, Jochen; Peiffer, Thomas; Perieanu, Adrian; Pietsch, Niklas; Poehlsen, Jennifer; Pöhlsen, Thomas; Rathjens, Denis; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schlieckau, Eike; Schmidt, Alexander; Seidel, Markus; Sola, Valentina; Stadie, Hartmut; Steinbrück, Georg; Troendle, Daniel; Usai, Emanuele; Vanelderen, Lukas; Vanhoefer, Annika; Barth, Christian; Baus, Colin; Berger, Joram; Böser, Christian; Butz, Erik; Chwalek, Thorsten; De Boer, Wim; Descroix, Alexis; Dierlamm, Alexander; Feindt, Michael; Frensch, Felix; Giffels, Manuel; Gilbert, Andrew; Hartmann, Frank; Hauth, Thomas; Husemann, Ulrich; Katkov, Igor; Kornmayer, Andreas; Lobelle Pardo, Patricia; Mozer, Matthias Ulrich; Müller, Thomas; Müller, Thomas; Nürnberg, Andreas; Quast, Gunter; Rabbertz, Klaus; Röcker, Steffen; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Ulrich, Ralf; Wagner-Kuhr, Jeannine; Wayand, Stefan; Weiler, Thomas; Wolf, Roger; Anagnostou, Georgios; Daskalakis, Georgios; Geralis, Theodoros; Giakoumopoulou, Viktoria Athina; Kyriakis, Aristotelis; Loukas, Demetrios; Markou, Athanasios; Markou, Christos; Psallidas, Andreas; Topsis-Giotis, Iasonas; Agapitos, Antonis; Kesisoglou, Stilianos; Panagiotou, Apostolos; Saoulidou, Niki; Stiliaris, Efstathios; Aslanoglou, Xenofon; Evangelou, Ioannis; Flouris, Giannis; Foudas, Costas; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Paradas, Evangelos; Strologas, John; Bencze, Gyorgy; Hajdu, Csaba; Hidas, Pàl; Horvath, Dezso; Sikler, Ferenc; Veszpremi, Viktor; Vesztergombi, Gyorgy; Zsigmond, Anna Julia; Beni, Noemi; Czellar, Sandor; Karancsi, János; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Makovec, Alajos; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Swain, Sanjay Kumar; Beri, Suman Bala; Bhatnagar, Vipin; Gupta, Ruchi; Bhawandeep, Bhawandeep; Kalsi, Amandeep Kaur; Kaur, Manjit; Kumar, Ramandeep; Mittal, Monika; Nishu, Nishu; Singh, Jasbir; Kumar, Ashok; Kumar, Arun; Ahuja, Sudha; Bhardwaj, Ashutosh; Choudhary, Brajesh C; Kumar, Ajay; Malhotra, Shivali; Naimuddin, Md; Ranjan, Kirti; Sharma, Varun; Banerjee, Sunanda; Bhattacharya, Satyaki; Chatterjee, Kalyanmoy; Dutta, Suchandra; Gomber, Bhawna; Jain, Sandhya; Jain, Shilpi; Khurana, Raman; Modak, Atanu; Mukherjee, Swagata; Roy, Debarati; Sarkar, Subir; Sharan, Manoj; Abdulsalam, Abdulla; Dutta, Dipanwita; Kumar, Vineet; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Topkar, Anita; Aziz, Tariq; Banerjee, Sudeshna; Bhowmik, Sandeep; Chatterjee, Rajdeep Mohan; Dewanjee, Ram Krishna; Dugad, Shashikant; Ganguly, Sanmay; Ghosh, Saranya; Guchait, Monoranjan; Gurtu, Atul; Kole, Gouranga; Kumar, Sanjeev; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Parida, Bibhuti; Sudhakar, Katta; Wickramage, Nadeesha; Bakhshiansohi, Hamed; Behnamian, Hadi; Etesami, Seyed Mohsen; Fahim, Ali; Goldouzian, Reza; Khakzad, Mohsen; Mohammadi Najafabadi, Mojtaba; Naseri, Mohsen; Paktinat Mehdiabadi, Saeid; Rezaei Hosseinabadi, Ferdos; Safarzadeh, Batool; Zeinali, Maryam; Felcini, Marta; Grunewald, Martin; Abbrescia, Marcello; Calabria, Cesare; Chhibra, Simranjit Singh; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Fiore, Luigi; Iaselli, Giuseppe; Maggi, Giorgio; Maggi, Marcello; My, Salvatore; Nuzzo, Salvatore; Pompili, Alexis; Pugliese, Gabriella; Radogna, Raffaella; Selvaggi, Giovanna; Sharma, Archana; Silvestris, Lucia; Venditti, Rosamaria; Verwilligen, Piet; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Brigliadori, Luca; Campanini, Renato; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Codispoti, Giuseppe; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Grandi, Claudio; Guiducci, Luigi; Marcellini, Stefano; Masetti, Gianni; Montanari, Alessandro; Navarria, Francesco; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gian Piero; Tosi, Nicolò; Travaglini, Riccardo; Albergo, Sebastiano; Cappello, Gigi; Chiorboli, Massimiliano; Costa, Salvatore; Giordano, Ferdinando; Potenza, Renato; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Gallo, Elisabetta; Gonzi, Sandro; Gori, Valentina; Lenzi, Piergiulio; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Fabbri, Franco; Piccolo, Davide; Ferretti, Roberta; Ferro, Fabrizio; Lo Vetere, Maurizio; Robutti, Enrico; Tosi, Silvano; Dinardo, Mauro Emanuele; Fiorendi, Sara; Gennai, Simone; Gerosa, Raffaele; Ghezzi, Alessio; Govoni, Pietro; Lucchini, Marco Toliman; Malvezzi, Sandra; Manzoni, Riccardo Andrea; Martelli, Arabella; Marzocchi, Badder; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Tabarelli de Fatis, Tommaso; Buontempo, Salvatore; Cavallo, Nicola; Di Guida, Salvatore; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Meola, Sabino; Merola, Mario; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bellato, Marco; Biasotto, Massimo; Branca, Antonio; Dall'Osso, Martino; Dorigo, Tommaso; Fantinel, Sergio; Fanzago, Federica; Galanti, Mario; Gasparini, Fabrizio; Gozzelino, Andrea; Kanishchev, Konstantin; Lacaprara, Stefano; Margoni, Martino; Meneguzzo, Anna Teresa; Pazzini, Jacopo; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Vanini, Sara; Zotto, Pierluigi; Zucchetta, Alberto; Zumerle, Gianni; Gabusi, Michele; Ratti, Sergio P; Re, Valerio; Riccardi, Cristina; Salvini, Paola; Vitulo, Paolo; Biasini, Maurizio; Bilei, Gian Mario; Ciangottini, Diego; Fanò, Livio; Lariccia, Paolo; Mantovani, Giancarlo; Menichelli, Mauro; Saha, Anirban; Santocchia, Attilio; Spiezia, Aniello; Androsov, Konstantin; Azzurri, Paolo; Bagliesi, Giuseppe; Bernardini, Jacopo; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; Ciocci, Maria Agnese; Dell'Orso, Roberto; Donato, Silvio; Fedi, Giacomo; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Grippo, Maria Teresa; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Moon, Chang-Seong; Palla, Fabrizio; Rizzi, Andrea; Savoy-Navarro, Aurore; Serban, Alin Titus; Spagnolo, Paolo; Squillacioti, Paola; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Vernieri, Caterina; Barone, Luciano; Cavallari, Francesca; D'imperio, Giulia; Del Re, Daniele; Diemoz, Marcella; Jorda, Clara; Longo, Egidio; Margaroli, Fabrizio; Meridiani, Paolo; Micheli, Francesco; Organtini, Giovanni; Paramatti, Riccardo; Rahatlou, Shahram; Rovelli, Chiara; Santanastasio, Francesco; Soffi, Livia; Traczyk, Piotr; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Bellan, Riccardo; Biino, Cristina; Cartiglia, Nicolo; Casasso, Stefano; Costa, Marco; Degano, Alessandro; Demaria, Natale; Finco, Linda; Mariotti, Chiara; Maselli, Silvia; Migliore, Ernesto; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Pacher, Luca; Pastrone, Nadia; Pelliccioni, Mario; Pinna Angioni, Gian Luca; Potenza, Alberto; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Solano, Ada; Staiano, Amedeo; Tamponi, Umberto; Belforte, Stefano; Candelise, Vieri; Casarsa, Massimo; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; La Licata, Chiara; Marone, Matteo; Schizzi, Andrea; Umer, Tomo; Zanetti, Anna; Chang, Sunghyun; Kropivnitskaya, Anna; Nam, Soon-Kwon; Kim, Dong Hee; Kim, Gui Nyun; Kim, Min Suk; Kong, Dae Jung; Lee, Sangeun; Oh, Young Do; Park, Hyangkyu; Sakharov, Alexandre; Son, Dong-Chul; Kim, Tae Jeong; Ryu, Min Sang; Kim, Jae Yool; Moon, Dong Ho; Song, Sanghyeon; Choi, Suyong; Gyun, Dooyeon; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Yongsun; Lee, Byounghoon; Lee, Kyong Sei; Park, Sung Keun; Roh, Youn; Yoo, Hwi Dong; Choi, Minkyoo; Kim, Ji Hyun; Park, Inkyu; Ryu, Geonmo; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Kim, Donghyun; Kwon, Eunhyang; Lee, Jongseok; Yu, Intae; Juodagalvis, Andrius; Komaragiri, Jyothsna Rani; Md Ali, Mohd Adli Bin; Casimiro Linares, Edgar; Castilla-Valdez, Heriberto; De La Cruz-Burelo, Eduard; Heredia-de La Cruz, Ivan; Hernandez-Almada, Alberto; Lopez-Fernandez, Ricardo; Sánchez Hernández, Alberto; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Pedraza, Isabel; Salazar Ibarguen, Humberto Antonio; Morelos Pineda, Antonio; Krofcheck, David; Butler, Philip H; Reucroft, Steve; Ahmad, Ashfaq; Ahmad, Muhammad; Hassan, Qamar; Hoorani, Hafeez R; Khan, Wajid Ali; Khurshid, Taimoor; Shoaib, Muhammad; Bialkowska, Helena; Bluj, Michal; Boimska, Bożena; Frueboes, Tomasz; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Zalewski, Piotr; Brona, Grzegorz; Bunkowski, Karol; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Misiura, Maciej; Olszewski, Michał; Bargassa, Pedrame; Beirão Da Cruz E Silva, Cristóvão; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Lloret Iglesias, Lara; Nguyen, Federico; Rodrigues Antunes, Joao; Seixas, Joao; Varela, Joao; Vischia, Pietro; Afanasiev, Serguei; Bunin, Pavel; Gavrilenko, Mikhail; Golutvin, Igor; Gorbunov, Ilya; Kamenev, Alexey; Karjavin, Vladimir; Konoplyanikov, Viktor; Lanev, Alexander; Malakhov, Alexander; Matveev, Viktor; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Shmatov, Sergey; Skatchkov, Nikolai; Smirnov, Vitaly; Zarubin, Anatoli; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Kuznetsova, Ekaterina; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Vorobyev, Andrey; Andreev, Yuri; Dermenev, Alexander; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Pashenkov, Anatoli; Tlisov, Danila; Toropin, Alexander; Epshteyn, Vladimir; Gavrilov, Vladimir; Lychkovskaya, Natalia; Popov, Vladimir; Pozdnyakov, Ivan; Safronov, Grigory; Semenov, Sergey; Spiridonov, Alexander; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Leonidov, Andrey; Mesyats, Gennady; Rusakov, Sergey V; Vinogradov, Alexey; Belyaev, Andrey; Boos, Edouard; Bunichev, Viacheslav; Dubinin, Mikhail; Dudko, Lev; Ershov, Alexander; Klyukhin, Vyacheslav; Kodolova, Olga; Lokhtin, Igor; Obraztsov, Stepan; Perfilov, Maxim; Savrin, Viktor; Snigirev, Alexander; Azhgirey, Igor; Bayshev, Igor; Bitioukov, Sergei; Kachanov, Vassili; Kalinin, Alexey; Konstantinov, Dmitri; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Ekmedzic, Marko; Milosevic, Jovan; Rekovic, Vladimir; Alcaraz Maestre, Juan; Battilana, Carlo; Calvo, Enrique; Cerrada, Marcos; Chamizo Llatas, Maria; Colino, Nicanor; De La Cruz, Begona; Delgado Peris, Antonio; Domínguez Vázquez, Daniel; Escalante Del Valle, Alberto; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M; Josa, Maria Isabel; Navarro De Martino, Eduardo; Pérez-Calero Yzquierdo, Antonio María; Puerta Pelayo, Jesus; Quintario Olmeda, Adrián; Redondo, Ignacio; Romero, Luciano; Senghi Soares, Mara; Albajar, Carmen; de Trocóniz, Jorge F; Missiroli, Marino; Moran, Dermot; Brun, Hugues; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Duarte Campderros, Jordi; Fernandez, Marcos; Gomez, Gervasio; Graziano, Alberto; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Piedra Gomez, Jonatan; Rodrigo, Teresa; Rodríguez-Marrero, Ana Yaiza; Ruiz-Jimeno, Alberto; Scodellaro, Luca; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Bachtis, Michail; Baillon, Paul; Ball, Austin; Barney, David; Benaglia, Andrea; Bendavid, Joshua; Benhabib, Lamia; Benitez, Jose F; Bloch, Philippe; Bocci, Andrea; Bonato, Alessio; Bondu, Olivier; Botta, Cristina; Breuker, Horst; Camporesi, Tiziano; Cerminara, Gianluca; Colafranceschi, Stefano; D'Alfonso, Mariarosaria; D'Enterria, David; Dabrowski, Anne; David Tinoco Mendes, Andre; De Guio, Federico; De Roeck, Albert; De Visscher, Simon; Di Marco, Emanuele; Dobson, Marc; Dordevic, Milos; Dorney, Brian; Dupont-Sagorin, Niels; Elliott-Peisert, Anna; Franzoni, Giovanni; Funk, Wolfgang; Gigi, Dominique; Gill, Karl; Giordano, Domenico; Girone, Maria; Glege, Frank; Guida, Roberto; Gundacker, Stefan; Guthoff, Moritz; Hammer, Josef; Hansen, Magnus; Harris, Philip; Hegeman, Jeroen; Innocente, Vincenzo; Janot, Patrick; Kousouris, Konstantinos; Krajczar, Krisztian; Lecoq, Paul; Lourenco, Carlos; Magini, Nicolo; Malgeri, Luca; Mannelli, Marcello; Marrouche, Jad; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moortgat, Filip; Morovic, Srecko; Mulders, Martijn; Orsini, Luciano; Pape, Luc; Perez, Emmanuelle; Petrilli, Achille; Petrucciani, Giovanni; Pfeiffer, Andreas; Pimiä, Martti; Piparo, Danilo; Plagge, Michael; Racz, Attila; Rojo, Juan; Rolandi, Gigi; Rovere, Marco; Sakulin, Hannes; Schäfer, Christoph; Schwick, Christoph; Sharma, Archana; Siegrist, Patrice; Silva, Pedro; Simon, Michal; Sphicas, Paraskevas; Spiga, Daniele; Steggemann, Jan; Stieger, Benjamin; Stoye, Markus; Takahashi, Yuta; Treille, Daniel; Tsirou, Andromachi; Veres, Gabor Istvan; Wardle, Nicholas; Wöhri, Hermine Katharina; Wollny, Heiner; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; Kotlinski, Danek; Langenegger, Urs; Renker, Dieter; Rohe, Tilman; Bachmair, Felix; Bäni, Lukas; Bianchini, Lorenzo; Buchmann, Marco-Andrea; Casal, Bruno; Chanon, Nicolas; Dissertori, Günther; Dittmar, Michael; Donegà, Mauro; Dünser, Marc; Eller, Philipp; Grab, Christoph; Hits, Dmitry; Hoss, Jan; Lustermann, Werner; Mangano, Boris; Marini, Andrea Carlo; Marionneau, Matthieu; Martinez Ruiz del Arbol, Pablo; Masciovecchio, Mario; Meister, Daniel; Mohr, Niklas; Musella, Pasquale; Nägeli, Christoph; Nessi-Tedaldi, Francesca; Pandolfi, Francesco; Pauss, Felicitas; Perrozzi, Luca; Peruzzi, Marco; Quittnat, Milena; Rebane, Liis; Rossini, Marco; Starodumov, Andrei; Takahashi, Maiko; Theofilatos, Konstantinos; Wallny, Rainer; Weber, Hannsjoerg Artur; Amsler, Claude; Canelli, Maria Florencia; Chiochia, Vincenzo; De Cosa, Annapaola; Hinzmann, Andreas; Hreus, Tomas; Kilminster, Benjamin; Lange, Clemens; Millan Mejias, Barbara; Ngadiuba, Jennifer; Pinna, Deborah; Robmann, Peter; Ronga, Frederic Jean; Taroni, Silvia; Verzetti, Mauro; Yang, Yong; Cardaci, Marco; Chen, Kuan-Hsin; Ferro, Cristina; Kuo, Chia-Ming; Lin, Willis; Lu, Yun-Ju; Volpe, Roberta; Yu, Shin-Shan; Chang, Paoti; Chang, You-Hao; Chao, Yuan; Chen, Kai-Feng; Chen, Po-Hsun; Dietz, Charles; Grundler, Ulysses; Hou, George Wei-Shu; Liu, Yueh-Feng; Lu, Rong-Shyang; Petrakou, Eleni; Tzeng, Yeng-Ming; Wilken, Rachel; Asavapibhop, Burin; Singh, Gurpreet; Srimanobhas, Norraphat; Suwonjandee, Narumon; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dozen, Candan; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gokbulut, Gul; Guler, Yalcin; Gurpinar, Emine; Hos, Ilknur; Kangal, Evrim Ersin; Kayis Topaksu, Aysel; Onengut, Gulsen; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, Ayse; Sunar Cerci, Deniz; Tali, Bayram; Topakli, Huseyin; Vergili, Mehmet; Zorbilmez, Caglar; Akin, Ilina Vasileva; Bilin, Bugra; Bilmis, Selcuk; Gamsizkan, Halil; Isildak, Bora; Karapinar, Guler; Ocalan, Kadir; Sekmen, Sezen; Surat, Ugur Emrah; Yalvac, Metin; Zeyrek, Mehmet; Albayrak, Elif Asli; Gülmez, Erhan; Kaya, Mithat; Kaya, Ozlem; Yetkin, Taylan; Cankocak, Kerem; Vardarlı, Fuat Ilkehan; Levchuk, Leonid; Sorokin, Pavel; Brooke, James John; Clement, Emyr; Cussans, David; Flacher, Henning; Goldstein, Joel; Grimes, Mark; Heath, Greg P; Heath, Helen F; Jacob, Jeson; Kreczko, Lukasz; Lucas, Chris; Meng, Zhaoxia; Newbold, Dave M; Paramesvaran, Sudarshan; Poll, Anthony; Sakuma, Tai; Seif El Nasr-storey, Sarah; Senkin, Sergey; Smith, Vincent J; Bell, Ken W; Belyaev, Alexander; Brew, Christopher; Brown, Robert M; Cockerill, David JA; Coughlan, John A; Harder, Kristian; Harper, Sam; Olaiya, Emmanuel; Petyt, David; Shepherd-Themistocleous, Claire; Thea, Alessandro; Tomalin, Ian R; Williams, Thomas; Womersley, William John; Worm, Steven; Baber, Mark; Bainbridge, Robert; Buchmuller, Oliver; Burton, Darren; Colling, David; Cripps, Nicholas; Dauncey, Paul; Davies, Gavin; Della Negra, Michel; Dunne, Patrick; Ferguson, William; Fulcher, Jonathan; Futyan, David; Hall, Geoffrey; Iles, Gregory; Jarvis, Martyn; Karapostoli, Georgia; Kenzie, Matthew; Lane, Rebecca; Lucas, Robyn; Lyons, Louis; Magnan, Anne-Marie; Malik, Sarah; Mathias, Bryn; Nash, Jordan; Nikitenko, Alexander; Pela, Joao; Pesaresi, Mark; Petridis, Konstantinos; Raymond, David Mark; Rogerson, Samuel; Rose, Andrew; Seez, Christopher; Sharp, Peter; Tapper, Alexander; Vazquez Acosta, Monica; Virdee, Tejinder; Zenz, Seth Conrad; Cole, Joanne; Hobson, Peter R; Khan, Akram; Kyberd, Paul; Leggat, Duncan; Leslie, Dawn; Reid, Ivan; Symonds, Philip; Teodorescu, Liliana; Turner, Mark; Dittmann, Jay; Hatakeyama, Kenichi; Kasmi, Azeddine; Liu, Hongxuan; Scarborough, Tara; Wu, Zhenbin; Charaf, Otman; Cooper, Seth; Henderson, Conor; Rumerio, Paolo; Avetisyan, Aram; Bose, Tulika; Fantasia, Cory; Lawson, Philip; Richardson, Clint; Rohlf, James; St John, Jason; Sulak, Lawrence; Alimena, Juliette; Berry, Edmund; Bhattacharya, Saptaparna; Christopher, Grant; Cutts, David; Demiragli, Zeynep; Dhingra, Nitish; Ferapontov, Alexey; Garabedian, Alex; Heintz, Ulrich; Kukartsev, Gennadiy; Laird, Edward; Landsberg, Greg; Luk, Michael; Narain, Meenakshi; Segala, Michael; Sinthuprasith, Tutanon; Speer, Thomas; Swanson, Joshua; Breedon, Richard; Breto, Guillermo; Calderon De La Barca Sanchez, Manuel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Conway, Rylan; Cox, Peter Timothy; Erbacher, Robin; Gardner, Michael; Ko, Winston; Lander, Richard; Mulhearn, Michael; Pellett, Dave; Pilot, Justin; Ricci-Tam, Francesca; Shalhout, Shalhout; Smith, John; Squires, Michael; Stolp, Dustin; Tripathi, Mani; Wilbur, Scott; Yohay, Rachel; Cousins, Robert; Everaerts, Pieter; Farrell, Chris; Hauser, Jay; Ignatenko, Mikhail; Rakness, Gregory; Takasugi, Eric; Valuev, Vyacheslav; Weber, Matthias; Burt, Kira; Clare, Robert; Ellison, John Anthony; Gary, J William; Hanson, Gail; Heilman, Jesse; Ivova Rikova, Mirena; Jandir, Pawandeep; Kennedy, Elizabeth; Lacroix, Florent; Long, Owen Rosser; Luthra, Arun; Malberti, Martina; Olmedo Negrete, Manuel; Shrinivas, Amithabh; Sumowidagdo, Suharyo; Wimpenny, Stephen; Branson, James G; Cerati, Giuseppe Benedetto; Cittolin, Sergio; D'Agnolo, Raffaele Tito; Holzner, André; Kelley, Ryan; Klein, Daniel; Letts, James; Macneill, Ian; Olivito, Dominick; Padhi, Sanjay; Palmer, Christopher; Pieri, Marco; Sani, Matteo; Sharma, Vivek; Simon, Sean; Tadel, Matevz; Tu, Yanjun; Vartak, Adish; Welke, Charles; Würthwein, Frank; Yagil, Avraham; Barge, Derek; Bradmiller-Feld, John; Campagnari, Claudio; Danielson, Thomas; Dishaw, Adam; Dutta, Valentina; Flowers, Kristen; Franco Sevilla, Manuel; Geffert, Paul; George, Christopher; Golf, Frank; Gouskos, Loukas; Incandela, Joe; Justus, Christopher; Mccoll, Nickolas; Richman, Jeffrey; Stuart, David; To, Wing; West, Christopher; Yoo, Jaehyeok; Apresyan, Artur; Bornheim, Adolf; Bunn, Julian; Chen, Yi; Duarte, Javier; Mott, Alexander; Newman, Harvey B; Pena, Cristian; Pierini, Maurizio; Spiropulu, Maria; Vlimant, Jean-Roch; Wilkinson, Richard; Xie, Si; Zhu, Ren-Yuan; Azzolini, Virginia; Calamba, Aristotle; Carlson, Benjamin; Ferguson, Thomas; Iiyama, Yutaro; Paulini, Manfred; Russ, James; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Ford, William T; Gaz, Alessandro; Krohn, Michael; Luiggi Lopez, Eduardo; Nauenberg, Uriel; Smith, James; Stenson, Kevin; Wagner, Stephen Robert; Alexander, James; Chatterjee, Avishek; Chaves, Jorge; Chu, Jennifer; Dittmer, Susan; Eggert, Nicholas; Mirman, Nathan; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Ryd, Anders; Salvati, Emmanuele; Skinnari, Louise; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Tucker, Jordan; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Apollinari, Giorgio; Bauerdick, Lothar AT; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C; Bolla, Gino; Burkett, Kevin; Butler, Joel Nathan; Cheung, Harry; Chlebana, Frank; Cihangir, Selcuk; Elvira, Victor Daniel; Fisk, Ian; Freeman, Jim; Gottschalk, Erik; Gray, Lindsey; Green, Dan; Grünendahl, Stefan; Gutsche, Oliver; Hanlon, Jim; Hare, Daryl; Harris, Robert M; Hirschauer, James; Hooberman, Benjamin; Jindariani, Sergo; Johnson, Marvin; Joshi, Umesh; Klima, Boaz; Kreis, Benjamin; Kwan, Simon; Linacre, Jacob; Lincoln, Don; Lipton, Ron; Liu, Tiehui; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Martinez Outschoorn, Verena Ingrid; Maruyama, Sho; Mason, David; McBride, Patricia; Merkel, Petra; Mishra, Kalanand; Mrenna, Stephen; Nahn, Steve; Newman-Holmes, Catherine; O'Dell, Vivian; Prokofyev, Oleg; Sexton-Kennedy, Elizabeth; Sharma, Seema; Soha, Aron; Spalding, William J; Spiegel, Leonard; Taylor, Lucas; Tkaczyk, Slawek; Tran, Nhan Viet; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitbeck, Andrew; Whitmore, Juliana; Yang, Fan; Acosta, Darin; Avery, Paul; Bortignon, Pierluigi; Bourilkov, Dimitri; Carver, Matthew; Curry, David; Das, Souvik; De Gruttola, Michele; Di Giovanni, Gian Piero; Field, Richard D; Fisher, Matthew; Furic, Ivan-Kresimir; Hugon, Justin; Konigsberg, Jacobo; Korytov, Andrey; Kypreos, Theodore; Low, Jia Fu; Matchev, Konstantin; Mei, Hualin; Milenovic, Predrag; Mitselmakher, Guenakh; Muniz, Lana; Rinkevicius, Aurelijus; Shchutska, Lesya; Snowball, Matthew; Sperka, David; Yelton, John; Zakaria, Mohammed; Hewamanage, Samantha; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Todd; Askew, Andrew; Bochenek, Joseph; Diamond, Brendan; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Johnson, Kurtis F; Prosper, Harrison; Veeraraghavan, Venkatesh; Weinberg, Marc; Baarmand, Marc M; Hohlmann, Marcus; Kalakhety, Himali; Yumiceva, Francisco; Adams, Mark Raymond; Apanasevich, Leonard; Berry, Douglas; Betts, Russell Richard; Bucinskaite, Inga; Cavanaugh, Richard; Evdokimov, Olga; Gauthier, Lucie; Gerber, Cecilia Elena; Hofman, David Jonathan; Kurt, Pelin; O'Brien, Christine; Sandoval Gonzalez, Irving Daniel; Silkworth, Christopher; Turner, Paul; Varelas, Nikos; Bilki, Burak; Clarida, Warren; Dilsiz, Kamuran; Haytmyradov, Maksat; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Ogul, Hasan; Onel, Yasar; Ozok, Ferhat; Penzo, Aldo; Rahmat, Rahmat; Sen, Sercan; Tan, Ping; Tiras, Emrah; Wetzel, James; Yi, Kai; Anderson, Ian; Barnett, Bruce Arnold; Blumenfeld, Barry; Bolognesi, Sara; Fehling, David; Gritsan, Andrei; Maksimovic, Petar; Martin, Christopher; Swartz, Morris; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Bruner, Christopher; Gray, Julia; Kenny III, Raymond Patrick; Majumder, Devdatta; Malek, Magdalena; Murray, Michael; Noonan, Daniel; Sanders, Stephen; Sekaric, Jadranka; Stringer, Robert; Wang, Quan; Wood, Jeffrey Scott; Chakaberia, Irakli; Ivanov, Andrew; Kaadze, Ketino; Khalil, Sadia; Makouski, Mikhail; Maravin, Yurii; Saini, Lovedeep Kaur; Skhirtladze, Nikoloz; Svintradze, Irakli; Gronberg, Jeffrey; Lange, David; Rebassoo, Finn; Wright, Douglas; Baden, Drew; Belloni, Alberto; Calvert, Brian; Eno, Sarah Catherine; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G; Kolberg, Ted; Lu, Ying; Mignerey, Alice; Pedro, Kevin; Skuja, Andris; Tonjes, Marguerite; Tonwar, Suresh C; Apyan, Aram; Barbieri, Richard; Busza, Wit; Cali, Ivan Amos; Chan, Matthew; Di Matteo, Leonardo; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Gulhan, Doga; Klute, Markus; Lai, Yue Shi; Lee, Yen-Jie; Levin, Andrew; Luckey, Paul David; Paus, Christoph; Ralph, Duncan; Roland, Christof; Roland, Gunther; Stephans, George; Sumorok, Konstanty; Velicanu, Dragos; Veverka, Jan; Wyslouch, Bolek; Yang, Mingming; Zanetti, Marco; Zhukova, Victoria; Dahmes, Bryan; Gude, Alexander; Kao, Shih-Chuan; Klapoetke, Kevin; Kubota, Yuichi; Mans, Jeremy; Nourbakhsh, Shervin; Pastika, Nathaniel; Rusack, Roger; Singovsky, Alexander; Tambe, Norbert; Turkewitz, Jared; Acosta, John Gabriel; Oliveros, Sandra; Avdeeva, Ekaterina; Bloom, Kenneth; Bose, Suvadeep; Claes, Daniel R; Dominguez, Aaron; Gonzalez Suarez, Rebeca; Keller, Jason; Knowlton, Dan; Kravchenko, Ilya; Lazo-Flores, Jose; Meier, Frank; Ratnikov, Fedor; Snow, Gregory R; Zvada, Marian; Dolen, James; Godshalk, Andrew; Iashvili, Ia; Kharchilava, Avto; Kumar, Ashish; Rappoccio, Salvatore; Alverson, George; Barberis, Emanuela; Baumgartel, Darin; Chasco, Matthew; Massironi, Andrea; Morse, David Michael; Nash, David; Orimoto, Toyoko; Trocino, Daniele; Wang, Ren-Jie; Wood, Darien; Zhang, Jinzhong; Hahn, Kristan Allan; Kubik, Andrew; Mucia, Nicholas; Odell, Nathaniel; Pollack, Brian; Pozdnyakov, Andrey; Schmitt, Michael Henry; Stoynev, Stoyan; Sung, Kevin; Velasco, Mayda; Won, Steven; Brinkerhoff, Andrew; Chan, Kwok Ming; Drozdetskiy, Alexey; Hildreth, Michael; Jessop, Colin; Karmgard, Daniel John; Kellams, Nathan; Lannon, Kevin; Lynch, Sean; Marinelli, Nancy; Musienko, Yuri; Pearson, Tessa; Planer, Michael; Ruchti, Randy; Smith, Geoffrey; Valls, Nil; Wayne, Mitchell; Wolf, Matthias; Woodard, Anna; Antonelli, Louis; Brinson, Jessica; Bylsma, Ben; Durkin, Lloyd Stanley; Flowers, Sean; Hart, Andrew; Hill, Christopher; Hughes, Richard; Kotov, Khristian; Ling, Ta-Yung; Luo, Wuming; Puigh, Darren; Rodenburg, Marissa; Winer, Brian L; Wolfe, Homer; Wulsin, Howard Wells; Driga, Olga; Elmer, Peter; Hardenbrook, Joshua; Hebda, Philip; Koay, Sue Ann; Lujan, Paul; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Piroué, Pierre; Quan, Xiaohang; Saka, Halil; Stickland, David; Tully, Christopher; Werner, Jeremy Scott; Zuranski, Andrzej; Brownson, Eric; Malik, Sudhir; Mendez, Hector; Ramirez Vargas, Juan Eduardo; Barnes, Virgil E; Benedetti, Daniele; Bortoletto, Daniela; De Mattia, Marco; Gutay, Laszlo; Hu, Zhen; Jha, Manoj; Jones, Matthew; Jung, Kurt; Kress, Matthew; Leonardo, Nuno; Miller, David Harry; Neumeister, Norbert; Radburn-Smith, Benjamin Charles; Shi, Xin; Shipsey, Ian; Silvers, David; Svyatkovskiy, Alexey; Wang, Fuqiang; Xie, Wei; Xu, Lingshan; Zablocki, Jakub; Parashar, Neeti; Stupak, John; Adair, Antony; Akgun, Bora; Ecklund, Karl Matthew; Geurts, Frank JM; Li, Wei; Michlin, Benjamin; Padley, Brian Paul; Redjimi, Radia; Roberts, Jay; Zabel, James; Betchart, Burton; Bodek, Arie; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Ferbel, Thomas; Garcia-Bellido, Aran; Goldenzweig, Pablo; Han, Jiyeon; Harel, Amnon; Hindrichs, Otto; Khukhunaishvili, Aleko; Korjenevski, Sergey; Petrillo, Gianluca; Vishnevskiy, Dmitry; Ciesielski, Robert; Demortier, Luc; Goulianos, Konstantin; Mesropian, Christina; Arora, Sanjay; Barker, Anthony; Chou, John Paul; Contreras-Campana, Christian; Contreras-Campana, Emmanuel; Duggan, Daniel; Ferencek, Dinko; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Kaplan, Steven; Lath, Amitabh; Panwalkar, Shruti; Park, Michael; Patel, Rishi; Salur, Sevil; Schnetzer, Steve; Sheffield, David; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Thomassen, Peter; Walker, Matthew; Rose, Keith; Spanier, Stefan; York, Andrew; Bouhali, Othmane; Castaneda Hernandez, Alfredo; Eusebi, Ricardo; Flanagan, Will; Gilmore, Jason; Kamon, Teruki; Khotilovich, Vadim; Krutelyov, Vyacheslav; Montalvo, Roy; Osipenkov, Ilya; Pakhotin, Yuriy; Perloff, Alexx; Roe, Jeffrey; Rose, Anthony; Safonov, Alexei; Suarez, Indara; Tatarinov, Aysen; Ulmer, Keith; Akchurin, Nural; Cowden, Christopher; Damgov, Jordan; Dragoiu, Cosmin; Dudero, Phillip Russell; Faulkner, James; Kovitanggoon, Kittikul; Kunori, Shuichi; Lee, Sung Won; Libeiro, Terence; Volobouev, Igor; Appelt, Eric; Delannoy, Andrés G; Greene, Senta; Gurrola, Alfredo; Johns, Willard; Maguire, Charles; Mao, Yaxian; Melo, Andrew; Sharma, Monika; Sheldon, Paul; Snook, Benjamin; Tuo, Shengquan; Velkovska, Julia; Arenton, Michael Wayne; Boutle, Sarah; Cox, Bradley; Francis, Brian; Goodell, Joseph; Hirosky, Robert; Ledovskoy, Alexander; Li, Hengne; Lin, Chuanzhe; Neu, Christopher; Wood, John; Clarke, Christopher; Harr, Robert; Karchin, Paul Edmund; Kottachchi Kankanamge Don, Chamath; Lamichhane, Pramod; Sturdy, Jared; Belknap, Donald; Carlsmith, Duncan; Cepeda, Maria; Dasu, Sridhara; Dodd, Laura; Duric, Senka; Friis, Evan; Hall-Wilton, Richard; Herndon, Matthew; Hervé, Alain; Klabbers, Pamela; Lanaro, Armando; Lazaridis, Christos; Levine, Aaron; Loveless, Richard; Mohapatra, Ajit; Ojalvo, Isabel; Perry, Thomas; Pierro, Giuseppe Antonio; Polese, Giovanni; Ross, Ian; Sarangi, Tapas; Savin, Alexander; Smith, Wesley H; Taylor, Devin; Vuosalo, Carl; Woods, Nathaniel

    2015-04-09

    Measurements of the differential and double-differential Drell-Yan cross sections in the dielectron and dimuon channels are presented. They are based on proton-proton collision data at $\\sqrt{s}$ = 8 TeV recorded with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 fb$^{-1} $. The measured inclusive cross section in the Z peak region (60-120 GeV), obtained from the combination of the dielectron and dimuon channels, is 1138 $\\pm$ 8 (exp) $\\pm$ 25 (theo) $\\pm$ 30 (lumi) pb, where the statistical uncertainty is negligible. The differential cross section $\\mathrm{d\\sigma/dm}$ in the dilepton mass range 15 to 2000 GeV is measured and corrected to the full phase space. The double-differential cross section $\\mathrm{d^2\\sigma / dm \\, d|y|}$ is also measured over the mass range 20 to 1500 GeV and absolute dilepton rapidity from 0 to 2.4. In addition, the ratios of the normalized differential cross sections measured at $\\sqrt{s}$ = 7 and 8 TeV are presented. These measurements are com...

  3. Bioinformatics analysis of differentially expressed proteins in prostate cancer based on proteomics data

    Directory of Open Access Journals (Sweden)

    Chen C

    2016-03-01

    Full Text Available Chen Chen,1 Li-Guo Zhang,1 Jian Liu,1 Hui Han,1 Ning Chen,1 An-Liang Yao,1 Shao-San Kang,1 Wei-Xing Gao,1 Hong Shen,2 Long-Jun Zhang,1 Ya-Peng Li,1 Feng-Hong Cao,1 Zhi-Guo Li3 1Department of Urology, North China University of Science and Technology Affiliated Hospital, 2Department of Modern Technology and Education Center, 3Department of Medical Research Center, International Science and Technology Cooperation Base of Geriatric Medicine, North China University of Science and Technology, Tangshan, People’s Republic of China Abstract: We mined the literature for proteomics data to examine the occurrence and metastasis of prostate cancer (PCa through a bioinformatics analysis. We divided the differentially expressed proteins (DEPs into two groups: the group consisting of PCa and benign tissues (P&b and the group presenting both high and low PCa metastatic tendencies (H&L. In the P&b group, we found 320 DEPs, 20 of which were reported more than three times, and DES was the most commonly reported. Among these DEPs, the expression levels of FGG, GSN, SERPINC1, TPM1, and TUBB4B have not yet been correlated with PCa. In the H&L group, we identified 353 DEPs, 13 of which were reported more than three times. Among these DEPs, MDH2 and MYH9 have not yet been correlated with PCa metastasis. We further confirmed that DES was differentially expressed between 30 cancer and 30 benign tissues. In addition, DEPs associated with protein transport, regulation of actin cytoskeleton, and the extracellular matrix (ECM–receptor interaction pathway were prevalent in the H&L group and have not yet been studied in detail in this context. Proteins related to homeostasis, the wound-healing response, focal adhesions, and the complement and coagulation pathways were overrepresented in both groups. Our findings suggest that the repeatedly reported DEPs in the two groups may function as potential biomarkers for detecting PCa and predicting its aggressiveness. Furthermore

  4. Differential Expression of Adhesion-Related Proteins and MAPK Pathways Lead to Suitable Osteoblast Differentiation of Human Mesenchymal Stem Cells Subpopulations.

    Science.gov (United States)

    Leyva-Leyva, Margarita; López-Díaz, Annia; Barrera, Lourdes; Camacho-Morales, Alberto; Hernandez-Aguilar, Felipe; Carrillo-Casas, Erika M; Arriaga-Pizano, Lourdes; Calderón-Pérez, Jaime; García-Álvarez, Jorge; Orozco-Hoyuela, Gabriel; Piña-Barba, Cristina; Rojas-Martínez, Augusto; Romero-Díaz, Víktor; Lara-Arias, Jorge; Rivera-Bolaños, Nancy; López-Camarillo, César; Moncada-Saucedo, Nidia; Galván-De los Santos, Alejandra; Meza-Urzúa, Fátima; Villarreal-Gómez, Luis; Fuentes-Mera, Lizeth

    2015-11-01

    Cellular adhesion enables communication between cells and their environment. Adhesion can be achieved throughout focal adhesions and its components influence osteoblast differentiation of human mesenchymal stem cells (hMSCs). Because cell adhesion and osteoblast differentiation are closely related, this article aimed to analyze the expression profiles of adhesion-related proteins during osteoblastic differentiation of two hMSCs subpopulations (CD105(+) and CD105(-)) and propose a strategy for assembling bone grafts based on its adhesion ability. In vitro experiments of osteogenic differentiation in CD105(-) cells showed superior adhesion efficiency and 2-fold increase of α-actinin expression compared with CD105(+) cells at the maturation stage. Interestingly, levels of activated β1-integrin increased in CD105(-) cells during the process. Additionally, the CD105(-) subpopulation showed 3-fold increase of phosphorylated FAK(Y397) compared to CD105(+) cells. Results also indicate that ERK1/2 was activated during CD105(-) bone differentiation and participation of mitogen-activated protein kinase (MAPK)-p38 in CD105(+) differentiation through a focal adhesion kinase (FAK)-independent pathway. In vivo trial demonstrated that grafts containing CD105(-) showed osteocytes embedded in a mineralized matrix, promoted adequate graft integration, increased host vascular infiltration, and efficient intramembranous repairing. In contrast, grafts containing CD105(+) showed deficient endochondral ossification and fibrocartilaginous tissue. Based on the expression of α-actinin, FAKy,(397) and ERK1/2 activation, we define maturation stage as critical for bone graft assembling. By in vitro assays, CD105(-) subpopulation showed superior adhesion efficiency compared to CD105(+) cells. Considering in vitro and in vivo assays, this study suggests that integration of a scaffold with CD105(-) subpopulation at the maturation stage represents an attractive strategy for clinical use in

  5. Differential equations a dynamical systems approach ordinary differential equations

    CERN Document Server

    Hubbard, John H

    1991-01-01

    This is a corrected third printing of the first part of the text Differential Equations: A Dynamical Systems Approach written by John Hubbard and Beverly West. The authors' main emphasis in this book is on ordinary differential equations. The book is most appropriate for upper level undergraduate and graduate students in the fields of mathematics, engineering, and applied mathematics, as well as the life sciences, physics and economics. Traditional courses on differential equations focus on techniques leading to solutions. Yet most differential equations do not admit solutions which can be written in elementary terms. The authors have taken the view that a differential equations defines functions; the object of the theory is to understand the behavior of these functions. The tools the authors use include qualitative and numerical methods besides the traditional analytic methods. The companion software, MacMath, is designed to bring these notions to life.

  6. Fractional Order Differentiation by Integration and Error Analysis in Noisy Environment

    KAUST Repository

    Liu, Dayan

    2015-03-31

    The integer order differentiation by integration method based on the Jacobi orthogonal polynomials for noisy signals was originally introduced by Mboup, Join and Fliess. We propose to extend this method from the integer order to the fractional order to estimate the fractional order derivatives of noisy signals. Firstly, two fractional order differentiators are deduced from the Jacobi orthogonal polynomial filter, using the Riemann-Liouville and the Caputo fractional order derivative definitions respectively. Exact and simple formulae for these differentiators are given by integral expressions. Hence, they can be used for both continuous-time and discrete-time models in on-line or off-line applications. Secondly, some error bounds are provided for the corresponding estimation errors. These bounds allow to study the design parameters\\' influence. The noise error contribution due to a large class of stochastic processes is studied in discrete case. The latter shows that the differentiator based on the Caputo fractional order derivative can cope with a class of noises, whose mean value and variance functions are polynomial time-varying. Thanks to the design parameters analysis, the proposed fractional order differentiators are significantly improved by admitting a time-delay. Thirdly, in order to reduce the calculation time for on-line applications, a recursive algorithm is proposed. Finally, the proposed differentiator based on the Riemann-Liouville fractional order derivative is used to estimate the state of a fractional order system and numerical simulations illustrate the accuracy and the robustness with respect to corrupting noises.

  7. Differential diagnosis between ameloblastoma and odontogenic keratocyst using computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kawazu, Toshiyuki; Yoshiura, Kazunori; Yuasa, Kenji; Kanda, Shigenobu; Ohzeki, Satoru; Shinohara, Masanori [Kyushu Univ., Fukuoka (Japan). Faculty of Dentistry; Araki, Kazuyuki; Higuchi, Yoshinori

    1997-09-01

    Radiographic features of ameloblastoma and odontogenic keratocyst are similar although their biological behaviors are different. Therefore, it is very important to differentiate these lesions before treatment. The aim of this study was to differentiate between the two lesions based on characteristic CT findings. Fifty-three patients diagnosed histopathologically as having ameloblastoma (29 cases) or odontogenic keratocyst (24 cases) and who underwent CT were evaluated radiologically, and some characteristic radiological features to differentiate both lesions were assessed. Ameloblastomas tended to be more than 40 mm in long diameter and 0.5 short/long diameter ratio, whereas odontogenic keratocysts were less than 40 mm and 0.5, respectively (P<0.05: Chi-square test). Buccal expansion of the cortex was seen more often in ameloblastomas than in odontogenic keratocysts (P<0.05: Chi-square test). Together with these features and internal high density structure, which was only seen in odontogenic keratocysts, differential diagnostic criteria between ameloblastomas and odontogenic keratocysts were proposed. Diagnostic accuracy based on these criteria was 84.9%. These results that our criteria to differentiate ameloblastomas from odontogenic keratocysts using CT are clinically useful prior to treatment. (author)

  8. Differential diagnosis between ameloblastoma and odontogenic keratocyst using computed tomography

    International Nuclear Information System (INIS)

    Kawazu, Toshiyuki; Yoshiura, Kazunori; Yuasa, Kenji; Kanda, Shigenobu; Ohzeki, Satoru; Shinohara, Masanori; Araki, Kazuyuki; Higuchi, Yoshinori

    1997-01-01

    Radiographic features of ameloblastoma and odontogenic keratocyst are similar although their biological behaviors are different. Therefore, it is very important to differentiate these lesions before treatment. The aim of this study was to differentiate between the two lesions based on characteristic CT findings. Fifty-three patients diagnosed histopathologically as having ameloblastoma (29 cases) or odontogenic keratocyst (24 cases) and who underwent CT were evaluated radiologically, and some characteristic radiological features to differentiate both lesions were assessed. Ameloblastomas tended to be more than 40 mm in long diameter and 0.5 short/long diameter ratio, whereas odontogenic keratocysts were less than 40 mm and 0.5, respectively (P<0.05: Chi-square test). Buccal expansion of the cortex was seen more often in ameloblastomas than in odontogenic keratocysts (P<0.05: Chi-square test). Together with these features and internal high density structure, which was only seen in odontogenic keratocysts, differential diagnostic criteria between ameloblastomas and odontogenic keratocysts were proposed. Diagnostic accuracy based on these criteria was 84.9%. These results that our criteria to differentiate ameloblastomas from odontogenic keratocysts using CT are clinically useful prior to treatment. (author)

  9. Symposium on Differential Geometry and Differential Equations

    CERN Document Server

    Berger, Marcel; Bryant, Robert

    1987-01-01

    The DD6 Symposium was, like its predecessors DD1 to DD5 both a research symposium and a summer seminar and concentrated on differential geometry. This volume contains a selection of the invited papers and some additional contributions. They cover recent advances and principal trends in current research in differential geometry.

  10. Schwarzian conditions for linear differential operators with selected differential Galois groups

    International Nuclear Information System (INIS)

    Abdelaziz, Y; Maillard, J-M

    2017-01-01

    We show that non-linear Schwarzian differential equations emerging from covariance symmetry conditions imposed on linear differential operators with hypergeometric function solutions can be generalized to arbitrary order linear differential operators with polynomial coefficients having selected differential Galois groups. For order three and order four linear differential operators we show that this pullback invariance up to conjugation eventually reduces to symmetric powers of an underlying order-two operator. We give, precisely, the conditions to have modular correspondences solutions for such Schwarzian differential equations, which was an open question in a previous paper. We analyze in detail a pullbacked hypergeometric example generalizing modular forms, that ushers a pullback invariance up to operator homomorphisms. We finally consider the more general problem of the equivalence of two different order-four linear differential Calabi–Yau operators up to pullbacks and conjugation, and clarify the cases where they have the same Yukawa couplings. (paper)

  11. Schwarzian conditions for linear differential operators with selected differential Galois groups

    Science.gov (United States)

    Abdelaziz, Y.; Maillard, J.-M.

    2017-11-01

    We show that non-linear Schwarzian differential equations emerging from covariance symmetry conditions imposed on linear differential operators with hypergeometric function solutions can be generalized to arbitrary order linear differential operators with polynomial coefficients having selected differential Galois groups. For order three and order four linear differential operators we show that this pullback invariance up to conjugation eventually reduces to symmetric powers of an underlying order-two operator. We give, precisely, the conditions to have modular correspondences solutions for such Schwarzian differential equations, which was an open question in a previous paper. We analyze in detail a pullbacked hypergeometric example generalizing modular forms, that ushers a pullback invariance up to operator homomorphisms. We finally consider the more general problem of the equivalence of two different order-four linear differential Calabi-Yau operators up to pullbacks and conjugation, and clarify the cases where they have the same Yukawa couplings.

  12. QNB: differential RNA methylation analysis for count-based small-sample sequencing data with a quad-negative binomial model.

    Science.gov (United States)

    Liu, Lian; Zhang, Shao-Wu; Huang, Yufei; Meng, Jia

    2017-08-31

    As a newly emerged research area, RNA epigenetics has drawn increasing attention recently for the participation of RNA methylation and other modifications in a number of crucial biological processes. Thanks to high throughput sequencing techniques, such as, MeRIP-Seq, transcriptome-wide RNA methylation profile is now available in the form of count-based data, with which it is often of interests to study the dynamics at epitranscriptomic layer. However, the sample size of RNA methylation experiment is usually very small due to its costs; and additionally, there usually exist a large number of genes whose methylation level cannot be accurately estimated due to their low expression level, making differential RNA methylation analysis a difficult task. We present QNB, a statistical approach for differential RNA methylation analysis with count-based small-sample sequencing data. Compared with previous approaches such as DRME model based on a statistical test covering the IP samples only with 2 negative binomial distributions, QNB is based on 4 independent negative binomial distributions with their variances and means linked by local regressions, and in the way, the input control samples are also properly taken care of. In addition, different from DRME approach, which relies only the input control sample only for estimating the background, QNB uses a more robust estimator for gene expression by combining information from both input and IP samples, which could largely improve the testing performance for very lowly expressed genes. QNB showed improved performance on both simulated and real MeRIP-Seq datasets when compared with competing algorithms. And the QNB model is also applicable to other datasets related RNA modifications, including but not limited to RNA bisulfite sequencing, m 1 A-Seq, Par-CLIP, RIP-Seq, etc.

  13. Concentrated Differential Privacy

    OpenAIRE

    Dwork, Cynthia; Rothblum, Guy N.

    2016-01-01

    We introduce Concentrated Differential Privacy, a relaxation of Differential Privacy enjoying better accuracy than both pure differential privacy and its popular "(epsilon,delta)" relaxation without compromising on cumulative privacy loss over multiple computations.

  14. Intercept Algorithm for Maneuvering Targets Based on Differential Geometry and Lyapunov Theory

    Directory of Open Access Journals (Sweden)

    Yunes Sh. ALQUDSI

    2018-03-01

    Full Text Available Nowadays, the homing guidance is utilized in the existed and under development air defense systems (ADS to effectively intercept the targets. The targets became smarter and capable to fly and maneuver professionally and the tendency to design missile with a small warhead became greater, then there is a pressure to produce a more precise and accurate missile guidance system based on intelligent algorithms to ensure effective interception of highly maneuverable targets. The aim of this paper is to present an intelligent guidance algorithm that effectively and precisely intercept the maneuverable and smart targets by virtue of the differential geometry (DG concepts. The intercept geometry and engagement kinematics, in addition to the direct intercept condition are developed and expressed in DG terms. The guidance algorithm is then developed by virtue of DG and Lyapunov theory. The study terminates with 2D engagement simulation with illustrative examples, to demonstrate that, the derived DG guidance algorithm is a generalized guidance approach and the well-known proportional navigation (PN guidance law is a subset of this approach.

  15. Machine learning-based quantitative texture analysis of CT images of small renal masses: Differentiation of angiomyolipoma without visible fat from renal cell carcinoma.

    Science.gov (United States)

    Feng, Zhichao; Rong, Pengfei; Cao, Peng; Zhou, Qingyu; Zhu, Wenwei; Yan, Zhimin; Liu, Qianyun; Wang, Wei

    2018-04-01

    To evaluate the diagnostic performance of machine-learning based quantitative texture analysis of CT images to differentiate small (≤ 4 cm) angiomyolipoma without visible fat (AMLwvf) from renal cell carcinoma (RCC). This single-institutional retrospective study included 58 patients with pathologically proven small renal mass (17 in AMLwvf and 41 in RCC groups). Texture features were extracted from the largest possible tumorous regions of interest (ROIs) by manual segmentation in preoperative three-phase CT images. Interobserver reliability and the Mann-Whitney U test were applied to select features preliminarily. Then support vector machine with recursive feature elimination (SVM-RFE) and synthetic minority oversampling technique (SMOTE) were adopted to establish discriminative classifiers, and the performance of classifiers was assessed. Of the 42 extracted features, 16 candidate features showed significant intergroup differences (P Machine learning analysis of CT texture features can facilitate the accurate differentiation of small AMLwvf from RCC. • Although conventional CT is useful for diagnosis of SRMs, it has limitations. • Machine-learning based CT texture analysis facilitate differentiation of small AMLwvf from RCC. • The highest accuracy of SVM-RFE+SMOTE classifier reached 93.9 %. • Texture analysis combined with machine-learning methods might spare unnecessary surgery for AMLwvf.

  16. An efficient approach for differentiating Alzheimer's disease from normal elderly based on multicenter MRI using gray-level invariant features.

    Directory of Open Access Journals (Sweden)

    Muwei Li

    Full Text Available Machine learning techniques, along with imaging markers extracted from structural magnetic resonance images, have been shown to increase the accuracy to differentiate patients with Alzheimer's disease (AD from normal elderly controls. Several forms of anatomical features, such as cortical volume, shape, and thickness, have demonstrated discriminative capability. These approaches rely on accurate non-linear image transformation, which could invite several nuisance factors, such as dependency on transformation parameters and the degree of anatomical abnormality, and an unpredictable influence of residual registration errors. In this study, we tested a simple method to extract disease-related anatomical features, which is suitable for initial stratification of the heterogeneous patient populations often encountered in clinical data. The method employed gray-level invariant features, which were extracted from linearly transformed images, to characterize AD-specific anatomical features. The intensity information from a disease-specific spatial masking, which was linearly registered to each patient, was used to capture the anatomical features. We implemented a two-step feature selection for anatomic recognition. First, a statistic-based feature selection was implemented to extract AD-related anatomical features while excluding non-significant features. Then, seven knowledge-based ROIs were used to capture the local discriminative powers of selected voxels within areas that were sensitive to AD or mild cognitive impairment (MCI. The discriminative capability of the proposed feature was measured by its performance in differentiating AD or MCI from normal elderly controls (NC using a support vector machine. The statistic-based feature selection, together with the knowledge-based masks, provided a promising solution for capturing anatomical features of the brain efficiently. For the analysis of clinical populations, which are inherently heterogeneous

  17. Developing a semantic web model for medical differential diagnosis recommendation.

    Science.gov (United States)

    Mohammed, Osama; Benlamri, Rachid

    2014-10-01

    In this paper we describe a novel model for differential diagnosis designed to make recommendations by utilizing semantic web technologies. The model is a response to a number of requirements, ranging from incorporating essential clinical diagnostic semantics to the integration of data mining for the process of identifying candidate diseases that best explain a set of clinical features. We introduce two major components, which we find essential to the construction of an integral differential diagnosis recommendation model: the evidence-based recommender component and the proximity-based recommender component. Both approaches are driven by disease diagnosis ontologies designed specifically to enable the process of generating diagnostic recommendations. These ontologies are the disease symptom ontology and the patient ontology. The evidence-based diagnosis process develops dynamic rules based on standardized clinical pathways. The proximity-based component employs data mining to provide clinicians with diagnosis predictions, as well as generates new diagnosis rules from provided training datasets. This article describes the integration between these two components along with the developed diagnosis ontologies to form a novel medical differential diagnosis recommendation model. This article also provides test cases from the implementation of the overall model, which shows quite promising diagnostic recommendation results.

  18. Application of Monte Carlo method to solving boundary value problem of differential equations

    International Nuclear Information System (INIS)

    Zuo Yinghong; Wang Jianguo

    2012-01-01

    This paper introduces the foundation of the Monte Carlo method and the way how to generate the random numbers. Based on the basic thought of the Monte Carlo method and finite differential method, the stochastic model for solving the boundary value problem of differential equations is built. To investigate the application of the Monte Carlo method to solving the boundary value problem of differential equations, the model is used to solve Laplace's equations with the first boundary condition and the unsteady heat transfer equation with initial values and boundary conditions. The results show that the boundary value problem of differential equations can be effectively solved with the Monte Carlo method, and the differential equations with initial condition can also be calculated by using a stochastic probability model which is based on the time-domain finite differential equations. Both the simulation results and theoretical analyses show that the errors of numerical results are lowered as the number of simulation particles is increased. (authors)

  19. Calculating differential Galois groups of parametrized differential equations, with applications to hypertranscendence

    OpenAIRE

    Hardouin, Charlotte; Minchenko, Andrei; Ovchinnikov, Alexey

    2015-01-01

    The main motivation of our work is to create an efficient algorithm that decides hypertranscendence of solutions of linear differential equations, via the parameterized differential and Galois theories. To achieve this, we expand the representation theory of linear differential algebraic groups and develop new algorithms that calculate unipotent radicals of parameterized differential Galois groups for differential equations whose coefficients are rational functions. P. Berman and M.F. Singer ...

  20. Non-asymptotic fractional order differentiators via an algebraic parametric method

    KAUST Repository

    Liu, Dayan; Gibaru, O.; Perruquetti, Wilfrid

    2012-01-01

    Recently, Mboup, Join and Fliess [27], [28] introduced non-asymptotic integer order differentiators by using an algebraic parametric estimation method [7], [8]. In this paper, in order to obtain non-asymptotic fractional order differentiators we apply this algebraic parametric method to truncated expansions of fractional Taylor series based on the Jumarie's modified Riemann-Liouville derivative [14]. Exact and simple formulae for these differentiators are given where a sliding integration window of a noisy signal involving Jacobi polynomials is used without complex mathematical deduction. The efficiency and the stability with respect to corrupting noises of the proposed fractional order differentiators are shown in numerical simulations. © 2012 IEEE.

  1. Non-asymptotic fractional order differentiators via an algebraic parametric method

    KAUST Repository

    Liu, Dayan

    2012-08-01

    Recently, Mboup, Join and Fliess [27], [28] introduced non-asymptotic integer order differentiators by using an algebraic parametric estimation method [7], [8]. In this paper, in order to obtain non-asymptotic fractional order differentiators we apply this algebraic parametric method to truncated expansions of fractional Taylor series based on the Jumarie\\'s modified Riemann-Liouville derivative [14]. Exact and simple formulae for these differentiators are given where a sliding integration window of a noisy signal involving Jacobi polynomials is used without complex mathematical deduction. The efficiency and the stability with respect to corrupting noises of the proposed fractional order differentiators are shown in numerical simulations. © 2012 IEEE.

  2. Exploring the interplay of resilience and energy consumption for a task-based partial differential equations preconditioner

    KAUST Repository

    Rizzi, F.

    2017-05-25

    We discuss algorithm-based resilience to silent data corruptions (SDCs) in a task-based domain-decomposition preconditioner for partial differential equations (PDEs). The algorithm exploits a reformulation of the PDE as a sampling problem, followed by a solution update through data manipulation that is resilient to SDCs. The implementation is based on a server-client model where all state information is held by the servers, while clients are designed solely as computational units. Scalability tests run up to ∼ 51K cores show a parallel efficiency greater than 90%. We use a 2D elliptic PDE and a fault model based on random single and double bit-flip to demonstrate the resilience of the application to synthetically injected SDC. We discuss two fault scenarios: one based on the corruption of all data of a target task, and the other involving the corruption of a single data point. We show that for our application, given the test problem considered, a four-fold increase in the number of faults only yields a 2% change in the overhead to overcome their presence, from 7% to 9%. We then discuss potential savings in energy consumption via dynamic voltage/frequency scaling, and its interplay with fault-rates, and application overhead.

  3. Exploring the interplay of resilience and energy consumption for a task-based partial differential equations preconditioner

    KAUST Repository

    Rizzi, F.; Morris, K.; Sargsyan, K.; Mycek, P.; Safta, C.; Le Maî tre, O.; Knio, Omar; Debusschere, B.J.

    2017-01-01

    We discuss algorithm-based resilience to silent data corruptions (SDCs) in a task-based domain-decomposition preconditioner for partial differential equations (PDEs). The algorithm exploits a reformulation of the PDE as a sampling problem, followed by a solution update through data manipulation that is resilient to SDCs. The implementation is based on a server-client model where all state information is held by the servers, while clients are designed solely as computational units. Scalability tests run up to ∼ 51K cores show a parallel efficiency greater than 90%. We use a 2D elliptic PDE and a fault model based on random single and double bit-flip to demonstrate the resilience of the application to synthetically injected SDC. We discuss two fault scenarios: one based on the corruption of all data of a target task, and the other involving the corruption of a single data point. We show that for our application, given the test problem considered, a four-fold increase in the number of faults only yields a 2% change in the overhead to overcome their presence, from 7% to 9%. We then discuss potential savings in energy consumption via dynamic voltage/frequency scaling, and its interplay with fault-rates, and application overhead.

  4. The challenge of legitimizing spatially differentiated regulation

    DEFF Research Database (Denmark)

    Thorsøe, Martin Hvarregaard; Graversgaard, Morten; Noe, Egon

    2017-01-01

    Differentiating regulation is a promising approach to agri-environmental regulation that may potentially reduce the environmental impact of agriculture at the lowest possible costs for the farmers and society, but also possesses a number of challenges. In this article, we explore the challenges...... to the legitimacy of agri-environmental regulation that occurs when the regulatory regime changes from general regulation to differentiated regulation. The analysis is based on a case study of the implementation of the Buffer zone act in Denmark – a regulation that prevents agricultural production in a 10 (later 9......) meter fringe around selected waterbodies. We distinguish between two different ways of legitimizing: Producing knowledge and participation. We conclude that to harvest some of the obvious benefits of differentiated regulation a number of challenges must be resolved, 1) ensuring legitimacy...

  5. Finding differentially expressed genes in high dimensional data: Rank based test statistic via a distance measure.

    Science.gov (United States)

    Mathur, Sunil; Sadana, Ajit

    2015-12-01

    We present a rank-based test statistic for the identification of differentially expressed genes using a distance measure. The proposed test statistic is highly robust against extreme values and does not assume the distribution of parent population. Simulation studies show that the proposed test is more powerful than some of the commonly used methods, such as paired t-test, Wilcoxon signed rank test, and significance analysis of microarray (SAM) under certain non-normal distributions. The asymptotic distribution of the test statistic, and the p-value function are discussed. The application of proposed method is shown using a real-life data set. © The Author(s) 2011.

  6. In Vitro Differentiation of Human Mesenchymal Stem Cells into Functional Cardiomyocyte-like Cells.

    Science.gov (United States)

    Szaraz, Peter; Gratch, Yarden S; Iqbal, Farwah; Librach, Clifford L

    2017-08-09

    Myocardial infarction and the subsequent ischemic cascade result in the extensive loss of cardiomyocytes, leading to congestive heart failure, the leading cause of mortality worldwide. Mesenchymal stem cells (MSCs) are a promising option for cell-based therapies to replace current, invasive techniques. MSCs can differentiate into mesenchymal lineages, including cardiac cell types, but complete differentiation into functional cells has not yet been achieved. Previous methods of differentiation were based on pharmacological agents or growth factors. However, more physiologically relevant strategies can also enable MSCs to undergo cardiomyogenic transformation. Here, we present a differentiation method using MSC aggregates on cardiomyocyte feeder layers to produce cardiomyocyte-like contracting cells. Human umbilical cord perivascular cells (HUCPVCs) have been shown to have a greater differentiation potential than commonly investigated MSC types, such as bone marrow MSCs (BMSCs). As an ontogenetically younger source, we investigated the cardiomyogenic potential of first-trimester (FTM) HUCPVCs compared to older sources. FTM HUCPVCs are a novel, rich source of MSCs that retain their in utero immunoprivileged properties when cultured in vitro. Using this differentiation protocol, FTM and term HUCPVCs achieved significantly increased cardiomyogenic differentiation compared to BMSCs, as indicated by the increased expression of cardiomyocyte markers (i.e., myocyte enhancer factor 2C, cardiac troponin T, heavy chain cardiac myosin, signal regulatory protein α, and connexin 43). They also maintained significantly lower immunogenicity, as demonstrated by their lower HLA-A expression and higher HLA-G expression. Applying aggregate-based differentiation, FTM HUCPVCs showed increased aggregate formation potential and generated contracting cells clusters within 1 week of co-culture on cardiac feeder layers, becoming the first MSC type to do so. Our results demonstrate that this

  7. Wavelength Selection Method Based on Differential Evolution for Precise Quantitative Analysis Using Terahertz Time-Domain Spectroscopy.

    Science.gov (United States)

    Li, Zhi; Chen, Weidong; Lian, Feiyu; Ge, Hongyi; Guan, Aihong

    2017-12-01

    Quantitative analysis of component mixtures is an important application of terahertz time-domain spectroscopy (THz-TDS) and has attracted broad interest in recent research. Although the accuracy of quantitative analysis using THz-TDS is affected by a host of factors, wavelength selection from the sample's THz absorption spectrum is the most crucial component. The raw spectrum consists of signals from the sample and scattering and other random disturbances that can critically influence the quantitative accuracy. For precise quantitative analysis using THz-TDS, the signal from the sample needs to be retained while the scattering and other noise sources are eliminated. In this paper, a novel wavelength selection method based on differential evolution (DE) is investigated. By performing quantitative experiments on a series of binary amino acid mixtures using THz-TDS, we demonstrate the efficacy of the DE-based wavelength selection method, which yields an error rate below 5%.

  8. Non-invasively predicting differentiation of pancreatic cancer through comparative serum metabonomic profiling.

    Science.gov (United States)

    Wen, Shi; Zhan, Bohan; Feng, Jianghua; Hu, Weize; Lin, Xianchao; Bai, Jianxi; Huang, Heguang

    2017-11-02

    The differentiation of pancreatic ductal adenocarcinoma (PDAC) could be associated with prognosis and may influence the choices of clinical management. No applicable methods could reliably predict the tumor differentiation preoperatively. Thus, the aim of this study was to compare the metabonomic profiling of pancreatic ductal adenocarcinoma with different differentiations and assess the feasibility of predicting tumor differentiations through metabonomic strategy based on nuclear magnetic resonance spectroscopy. By implanting pancreatic cancer cell strains Panc-1, Bxpc-3 and SW1990 in nude mice in situ, we successfully established the orthotopic xenograft models of PDAC with different differentiations. The metabonomic profiling of serum from different PDAC was achieved and analyzed by using 1 H nuclear magnetic resonance (NMR) spectroscopy combined with the multivariate statistical analysis. Then, the differential metabolites acquired were used for enrichment analysis of metabolic pathways to get a deep insight. An obvious metabonomic difference was demonstrated between all groups and the pattern recognition models were established successfully. The higher concentrations of amino acids, glycolytic and glutaminolytic participators in SW1990 and choline-contain metabolites in Panc-1 relative to other PDAC cells were demonstrated, which may be served as potential indicators for tumor differentiation. The metabolic pathways and differential metabolites identified in current study may be associated with specific pathways such as serine-glycine-one-carbon and glutaminolytic pathways, which can regulate tumorous proliferation and epigenetic regulation. The NMR-based metabonomic strategy may be served as a non-invasive detection method for predicting tumor differentiation preoperatively.

  9. Differential-phase-shift quantum key distribution using coherent light

    International Nuclear Information System (INIS)

    Inoue, K.; Waks, E.; Yamamoto, Y.

    2003-01-01

    Differential-phase-shift quantum key distribution based on two nonorthogonal states is described. A weak coherent pulse train is sent from Alice to Bob, in which the phase of each pulse is randomly modulated by {0,π}. Bob measures the differential phase by a one-bit delay circuit. The system has a simple configuration without the need for an interferometer and a bright reference pulse in Alice's site, unlike the conventional QKD system based on two nonorthogonal states, and has an advantage of improved communication efficiency. The principle of the operation is successfully demonstrated in experiments

  10. Modeling and Prediction Using Stochastic Differential Equations

    DEFF Research Database (Denmark)

    Juhl, Rune; Møller, Jan Kloppenborg; Jørgensen, John Bagterp

    2016-01-01

    Pharmacokinetic/pharmakodynamic (PK/PD) modeling for a single subject is most often performed using nonlinear models based on deterministic ordinary differential equations (ODEs), and the variation between subjects in a population of subjects is described using a population (mixed effects) setup...... deterministic and can predict the future perfectly. A more realistic approach would be to allow for randomness in the model due to e.g., the model be too simple or errors in input. We describe a modeling and prediction setup which better reflects reality and suggests stochastic differential equations (SDEs...

  11. Clinical score to differentiate scrub typhus and dengue: A tool to differentiate scrub typhus and dengue

    Directory of Open Access Journals (Sweden)

    Shubhanker Mitra

    2017-01-01

    Full Text Available Background: Dengue and scrub typhus share similar clinical and epidemiological features, and are difficult to differentiate at initial presentation. Many places are endemic to both these infections where they comprise the majority of acute undifferentiated febrile illnesses. Materials and Methods: We aimed to develop a score that can differentiate scrub typhus from dengue. In this cross-sectional study, 188 cases of scrub typhus and 201 cases of dengue infection who presented to the emergency department or medicine outpatient clinic from September 2012 to April 2013 were included. Univariate followed by multivariate logistic regression analysis was performed to identify clinical features and laboratory results that were significantly different between the two groups. Each variable was assigned scores based on the strength of association and receiver operating characteristics area under the curve (ROC-AUC was generated and compared. Six scoring models were explored to ascertain the model with the best fit. Results: Model 2 was developed using the following six variables: oxygen saturation (>90%, ≤90%, total white blood cell count (7000 cells/cumm, hemoglobin (≤14 and >14 g/dL, total bilirubin (200 and ≥200 IU/dL, and altered sensorium (present or absent. Each variable was assigned scores based on its strength of association. The AUC-ROC curve (95% confidence interval for model 2 was 0.84 (0.79–0.89. At the cut off score of 13, the sensitivity and specificity were 85% and 77% respectively, with a higher score favoring dengue. Conclusion: In areas of high burden of ST and dengue, model 2 (the “clinical score to differentiate scrub typhus and dengue fever” is a simple and rapid clinical scoring system that may be used to differentiate scrub typhus and dengue at initial presentation.

  12. Clinical Score to Differentiate Scrub Typhus and Dengue: A Tool to Differentiate Scrub Typhus and Dengue.

    Science.gov (United States)

    Mitra, Shubhanker; Gautam, Ira; Jambugulam, Mohan; Abhilash, Kundavaram Paul Prabhakar; Jayaseeelan, Vishalakshi

    2017-01-01

    Dengue and scrub typhus share similar clinical and epidemiological features, and are difficult to differentiate at initial presentation. Many places are endemic to both these infections where they comprise the majority of acute undifferentiated febrile illnesses. We aimed to develop a score that can differentiate scrub typhus from dengue. In this cross-sectional study, 188 cases of scrub typhus and 201 cases of dengue infection who presented to the emergency department or medicine outpatient clinic from September 2012 to April 2013 were included. Univariate followed by multivariate logistic regression analysis was performed to identify clinical features and laboratory results that were significantly different between the two groups. Each variable was assigned scores based on the strength of association and receiver operating characteristics area under the curve (ROC-AUC) was generated and compared. Six scoring models were explored to ascertain the model with the best fit. Model 2 was developed using the following six variables: oxygen saturation (>90%, ≤90%), total white blood cell count (7000 cells/cumm), hemoglobin (≤14 and >14 g/dL), total bilirubin (200 and ≥200 IU/dL), and altered sensorium (present or absent). Each variable was assigned scores based on its strength of association. The AUC-ROC curve (95% confidence interval) for model 2 was 0.84 (0.79-0.89). At the cut off score of 13, the sensitivity and specificity were 85% and 77% respectively, with a higher score favoring dengue. In areas of high burden of ST and dengue, model 2 (the "clinical score to differentiate scrub typhus and dengue fever") is a simple and rapid clinical scoring system that may be used to differentiate scrub typhus and dengue at initial presentation.

  13. A new multi-step technique with differential transform method for analytical solution of some nonlinear variable delay differential equations.

    Science.gov (United States)

    Benhammouda, Brahim; Vazquez-Leal, Hector

    2016-01-01

    This work presents an analytical solution of some nonlinear delay differential equations (DDEs) with variable delays. Such DDEs are difficult to treat numerically and cannot be solved by existing general purpose codes. A new method of steps combined with the differential transform method (DTM) is proposed as a powerful tool to solve these DDEs. This method reduces the DDEs to ordinary differential equations that are then solved by the DTM. Furthermore, we show that the solutions can be improved by Laplace-Padé resummation method. Two examples are presented to show the efficiency of the proposed technique. The main advantage of this technique is that it possesses a simple procedure based on a few straight forward steps and can be combined with any analytical method, other than the DTM, like the homotopy perturbation method.

  14. High Weak Order Methods for Stochastic Differential Equations Based on Modified Equations

    KAUST Repository

    Abdulle, Assyr; Cohen, David; Vilmart, Gilles; Zygalakis, Konstantinos C.

    2012-01-01

    © 2012 Society for Industrial and Applied Mathematics. Inspired by recent advances in the theory of modified differential equations, we propose a new methodology for constructing numerical integrators with high weak order for the time integration

  15. Simple algorithm to estimate mean-field effects from minor differential permeability curves based on the Preisach model

    International Nuclear Information System (INIS)

    Perevertov, Oleksiy

    2003-01-01

    The classical Preisach model (PM) of magnetic hysteresis requires that any minor differential permeability curve lies under minor curves with larger field amplitude. Measurements of ferromagnetic materials show that very often this is not true. By applying the classical PM formalism to measured minor curves one can discover that it leads to an oval-shaped region on each half of the Preisach plane where the calculations produce negative values in the Preisach function. Introducing an effective field, which differs from the applied one by a mean-field term proportional to the magnetization, usually solves this problem. Complex techniques exist to estimate the minimum necessary proportionality constant (the moving parameter). In this paper we propose a simpler way to estimate the mean-field effects for use in nondestructive testing, which is based on experience from the measurements of industrial steels. A new parameter (parameter of shift) is introduced, which monitors the mean-field effects. The relation between the shift parameter and the moving one was studied for a number of steels. From preliminary experiments no correlation was found between the shift parameter and the classical magnetic ones such as the coercive field, maximum differential permeability and remanent magnetization

  16. ON ASYMTOTIC APPROXIMATIONS OF FIRST INTEGRALS FOR DIFFERENTIAL AND DIFFERENCE EQUATIONS

    Directory of Open Access Journals (Sweden)

    W.T. van Horssen

    2007-04-01

    Full Text Available In this paper the concept of integrating factors for differential equations and the concept of invariance factors for difference equations to obtain first integrals or invariants will be presented. It will be shown that all integrating factors have to satisfya system of partial differential equations, and that all invariance factors have to satisfy a functional equation. In the period 1997-2001 a perturbation method based on integrating vectors was developed to approximate first integrals for systems of ordinary differential equations. This perturbation method will be reviewed shortly. Also in the paper the first results in the development of a perturbation method for difference equations based on invariance factors will be presented.

  17. Stability of some Cactaceae proteins based on fluorescence, circular dichroism, and differential scanning calorimetry measurements.

    Science.gov (United States)

    Gorinstein, S; Zemser, M; Vargas-Albores, F; Ochoa, J L; Paredes-Lopez, O; Scheler, C; Aksu, S; Salnikow, J

    1999-02-01

    Characterization of three cactus proteins (native and denatured) from Machaerocereus gummosus (Pitahaya agria), Lophocereu schottii (Garambullo), and Cholla opuntia (Cholla), was based on electrophoretic, fluorescence, CD (circular dichroism), DSC (differential scanning calorimetry), and FT-IR (Fourier transform infrared) measurements. The obtained results of intrinsic fluorescence, DSC, and CD were dissimilar for the three species of cactus, providing evidence of differences in secondary and tertiary structures. Cactus proteins may be situated in the following order corresponding to their relative stability: Machaerocereus gummosus (Pitahaya agria) > Cholla opuntia (Cholla) > Lophocereu schottii (Garambullo). Thermodynamic properties of proteins and their changes upon denaturation (temperature of denaturation, enthalphy, and the number of ruptured hydrogen bonds) were correlated with the secondary structure of proteins and disappearance of alpha-helix.

  18. Measurement of differential and double-differential neutron emission cross-sections for {sup 9}Be at 21.94 MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yaling [Lanzhou University, School of Nuclear Science and Technology, Lanzhou (China); Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Ruan, Xichao; Huang, Hanxiong; Ren, Jie; Li, Xia; Nie, Yangbo [China Institute of Atomic Energy, Key Laboratory of Nuclear Data, Beijing (China); Li, Yongming [Chinese Academy of Engineering Physics, Mianyang, Sichuan (China); Zhou, Bin [Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China); Wei, Zheng; Yao, Zeen [Lanzhou University, School of Nuclear Science and Technology, Lanzhou (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou (China); Gao, Xiaofei; Yang, Lei [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

    2017-12-15

    The secondary neutron emission differential and double-differential cross sections (DX and DDXs) of n + {sup 9}Be have been measured at the neutron energy of 21.94 MeV using the multi-detector fast neutron time-of-flight (TOF) spectrometer. The data was derived by comparing the measured TOF spectra with detailed Monte Carlo simulation, and corrected with n-p scattering cross section. Meanwhile, theoretical calculations based on the Hauser-Feshbach and exciton model have been performed to compare with experimental data. Measured differential cross sections were also compared with other measurements. It was found that the experimental results were in agreement with other measurements and theoretical calculations, while discrepancies were also present in the whole energy region and at some angles. (orig.)

  19. Population stochastic modelling (PSM)-An R package for mixed-effects models based on stochastic differential equations

    DEFF Research Database (Denmark)

    Klim, Søren; Mortensen, Stig Bousgaard; Kristensen, Niels Rode

    2009-01-01

    are often partly ignored in PK/PD modelling although violating the hypothesis for many standard statistical tests. This article presents a package for the statistical program R that is able to handle SDEs in a mixed-effects setting. The estimation method implemented is the FOCE1 approximation......The extension from ordinary to stochastic differential equations (SDEs) in pharmacokinetic and pharmacodynamic (PK/PD) modelling is an emerging field and has been motivated in a number of articles [N.R. Kristensen, H. Madsen, S.H. Ingwersen, Using stochastic differential equations for PK/PD model...... development, J. Pharmacokinet. Pharmacodyn. 32 (February(l)) (2005) 109-141; C.W. Tornoe, R.V Overgaard, H. Agerso, H.A. Nielsen, H. Madsen, E.N. Jonsson, Stochastic differential equations in NONMEM: implementation, application, and comparison with ordinary differential equations, Pharm. Res. 22 (August(8...

  20. Differential gene expression during Trypanosoma cruzi metacyclogenesis

    Directory of Open Access Journals (Sweden)

    Marco Aurelio Krieger

    1999-09-01

    Full Text Available The transformation of epimastigotes into metacyclic trypomastigotes involves changes in the pattern of expressed genes, resulting in important morphological and functional differences between these developmental forms of Trypanosoma cruzi. In order to identify and characterize genes involved in triggering the metacyclogenesis process and in conferring to metacyclic trypomastigotes their stage specific biological properties, we have developed a method allowing the isolation of genes specifically expressed when comparing two close related cell populations (representation of differential expression or RDE. The method is based on the PCR amplification of gene sequences selected by hybridizing and subtracting the populations in such a way that after some cycles of hybridization-amplification genes specific to a given population are highly enriched. The use of this method in the analysis of differential gene expression during T. cruzi metacyclogenesis (6 hr and 24 hr of differentiation and metacyclic trypomastigotes resulted in the isolation of several clones from each time point. Northern blot analysis showed that some genes are transiently expressed (6 hr and 24 hr differentiating cells, while others are present in differentiating cells and in metacyclic trypomastigotes. Nucleotide sequencing of six clones characterized so far showed that they do not display any homology to gene sequences available in the GeneBank.

  1. 3D facial expression recognition based on histograms of surface differential quantities

    KAUST Repository

    Li, Huibin; Morvan, Jean-Marie; Chen, Liming

    2011-01-01

    . To characterize shape information of the local neighborhood of facial landmarks, we calculate the weighted statistical distributions of surface differential quantities, including histogram of mesh gradient (HoG) and histogram of shape index (HoS). Normal cycle

  2. A new perspective on relativistic transformation: formulation of the differential Lorentz transformation based on first principles

    International Nuclear Information System (INIS)

    Huang, Young-Sea

    2010-01-01

    The differential Lorentz transformation is formulated solely from the principle of relativity and the invariance of the speed of light. The differential Lorentz transformation transforms physical quantities, instead of space-time coordinates, to keep laws of nature form-invariant among inertial frames. The new relativistic transformation fulfills the principle of relativity, whereas the usual Lorentz transformation of space-time coordinates does not. Furthermore, the new relativistic transformation is compatible with quantum mechanics. The formulation herein provides theoretical foundations for the differential Lorentz transformation as the fundamental relativistic transformation.

  3. An efficient computer based wavelets approximation method to solve Fuzzy boundary value differential equations

    Science.gov (United States)

    Alam Khan, Najeeb; Razzaq, Oyoon Abdul

    2016-03-01

    In the present work a wavelets approximation method is employed to solve fuzzy boundary value differential equations (FBVDEs). Essentially, a truncated Legendre wavelets series together with the Legendre wavelets operational matrix of derivative are utilized to convert FB- VDE into a simple computational problem by reducing it into a system of fuzzy algebraic linear equations. The capability of scheme is investigated on second order FB- VDE considered under generalized H-differentiability. Solutions are represented graphically showing competency and accuracy of this method.

  4. Differential games

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This volume lays the mathematical foundations for the theory of differential games, developing a rigorous mathematical framework with existence theorems. It begins with a precise definition of a differential game and advances to considerations of games of fixed duration, games of pursuit and evasion, the computation of saddle points, games of survival, and games with restricted phase coordinates. Final chapters cover selected topics (including capturability and games with delayed information) and N-person games.Geared toward graduate students, Differential Games will be of particular interest

  5. Atmospheres of partially differentiated super-Earth exoplanets

    Science.gov (United States)

    Schaefer, Laura; Sasselov, Dimitar

    2015-11-01

    Terrestrial exoplanets have been discovered in a range of sizes, densities and orbital locations that defy our expectations based upon the Solar System. Planets discovered to date with radii less than ~1.5-1.6 Earth radii all seem to fall on an iso-density curve with the Earth [1]. However, mass and radius determinations, which depend on the known properties of the host star, are not accurate enough to distinguish between a fully differentiated three-layer planet (core, mantle, ocean/atmosphere) and an incompletely differentiated planet [2]. Full differentiation of a planet will depend upon the conditions at the time of accretion, including the abundance of short-lived radioisotopes, which will vary from system to system, as well as the number of giant impacts the planet experiences. Furthermore, separation of metal and silicates at the much larger pressures found inside super-Earths will depend on how the chemistry of these materials change at high pressures. There are therefore hints emerging that not all super-Earths will be fully differentiated. Incomplete differentiation will result in a more reduced mantle oxidation state and may have implications for the composition of an outgassed atmosphere. Here we will present the first results from a chemical equilibrium model of the composition of such an outgassed atmosphere and discuss the possibility of distinguishing between fully and incompletely differentiated planets through atmospheric observations.[1] Rogers, L. 2015. ApJ, 801, 41. [2] Zeng, L. & Sasselov, D. 2013. PASP, 125, 227.

  6. Steering redundancy for self-driving vehicles using differential braking

    Science.gov (United States)

    Jonasson, M.; Thor, M.

    2018-05-01

    This paper describes how differential braking can be used to turn a vehicle in the context of providing fail-operational control for self-driving vehicles. Two vehicle models are developed with differential input. The models are used to explain the bounds of curvature that differential braking provides and they are then validated with measurements in a test vehicle. Particular focus is paid on wheel suspension effects that significantly influence the obtained curvature. The vehicle behaviour and its limitations due to wheel suspension effects are, owing to the vehicle models, defined and explained. Finally, a model-based controller is developed to control the vehicle curvature during a fault by differential braking. The controller is designed to compensate for wheel angle disturbance that is likely to occur during the control event.

  7. Using Network-Based Language Analysis to Bridge Expertise and Cultivate Sensitivity to Differentiated Language Use in Interdisciplinary Geoscience Research

    Science.gov (United States)

    Hannah, M. A.; Simeone, M.

    2017-12-01

    On interdisciplinary teams, expertise is varied, as is evidenced by differences in team members' language use. Developing strategies to combine that expertise and bridge differentiated language practices is especially difficult between geoscience subdisciplines as researchers assume they use a shared language—vocabulary, jargon, codes, linguistic styles. In our paper, we discuss a network-based approach used to identify varied expertise and language practices between geoscientists (n=29) on a NSF team funded to study how deep and surface Earth processes worked together to give rise to the Great Oxygenation Event. We describe how we modeled the team's expertise from a language corpus consisting of 220 oxygen-related terms frequently used by team members and then compared their understanding of the terms to develop interventions to bridge the team's expertise. Corpus terms were identified via team member interviews, observations of members' interactions at research meetings, and discourse analysis of members' publications. Comparisons of members' language use were based on a Likert scale survey that asked members to assess how they understood a term; how frequently they used a term; and whether they conceptualized a term as an object or process. Rather than use our method as a communication audit tool (Zwijze-Koning & de Jong, 2015), teams can proactively use it in a project's early stages to assess the contours of the team's differentiated expertise and show where specialized knowledge resides in the team, where latent or non-obvious expertise exists, where expertise overlaps, and where gaps are in the team's knowledge. With this information, teams can make evidence based recommendations to forward their work such as allocating resources; identifying and empowering members to serve as connectors and lead cross-functional project initiatives; and developing strategies to avoid communication barriers. The method also generates models for teaching language

  8. [Feature extraction for breast cancer data based on geometric algebra theory and feature selection using differential evolution].

    Science.gov (United States)

    Li, Jing; Hong, Wenxue

    2014-12-01

    The feature extraction and feature selection are the important issues in pattern recognition. Based on the geometric algebra representation of vector, a new feature extraction method using blade coefficient of geometric algebra was proposed in this study. At the same time, an improved differential evolution (DE) feature selection method was proposed to solve the elevated high dimension issue. The simple linear discriminant analysis was used as the classifier. The result of the 10-fold cross-validation (10 CV) classification of public breast cancer biomedical dataset was more than 96% and proved superior to that of the original features and traditional feature extraction method.

  9. A protocol describing the use of a recombinant protein-based, animal product-free medium (APEL) for human embryonic stem cell differentiation as spin embryoid bodies.

    Science.gov (United States)

    Ng, Elizabeth S; Davis, Richard; Stanley, Edouard G; Elefanty, Andrew G

    2008-01-01

    In order to promote the uniform and reproducible differentiation of human embryonic stem cells (HESCs) in response to exogenously added growth factors, we have developed a method (spin embryoid bodies (EBs)) that uses a recombinant protein-based, animal product-free medium in which HESCs are aggregated by centrifugation to form EBs. In this protocol we describe the formulation of this medium, denoted APEL (Albumin Polyvinylalcohol Essential Lipids), and its use in spin EB differentiation of HESCs. We also describe a more economical variant, BPEL (Bovine Serum Albumin (BSA) Polyvinylalchohol Essential Lipids), in which BSA replaces the recombinant human albumin. The integration of a medium that includes only defined and recombinant components with a defined number of cells to initiate EB formation results in a generally applicable, robust platform for growth factor-directed HESC differentiation.

  10. Patch Similarity Modulus and Difference Curvature Based Fourth-Order Partial Differential Equation for Image Denoising

    Directory of Open Access Journals (Sweden)

    Yunjiao Bai

    2015-01-01

    Full Text Available The traditional fourth-order nonlinear diffusion denoising model suffers the isolated speckles and the loss of fine details in the processed image. For this reason, a new fourth-order partial differential equation based on the patch similarity modulus and the difference curvature is proposed for image denoising. First, based on the intensity similarity of neighbor pixels, this paper presents a new edge indicator called patch similarity modulus, which is strongly robust to noise. Furthermore, the difference curvature which can effectively distinguish between edges and noise is incorporated into the denoising algorithm to determine the diffusion process by adaptively adjusting the size of the diffusion coefficient. The experimental results show that the proposed algorithm can not only preserve edges and texture details, but also avoid isolated speckles and staircase effect while filtering out noise. And the proposed algorithm has a better performance for the images with abundant details. Additionally, the subjective visual quality and objective evaluation index of the denoised image obtained by the proposed algorithm are higher than the ones from the related methods.

  11. Trend of telomerase activity change during human iPSC self-renewal and differentiation revealed by a quartz crystal microbalance based assay

    Science.gov (United States)

    Zhou, Yitian; Zhou, Ping; Xin, Yinqiang; Wang, Jie; Zhu, Zhiqiang; Hu, Ji; Wei, Shicheng; Ma, Hongwei

    2014-11-01

    Telomerase plays an important role in governing the life span of cells for its capacity to extend telomeres. As high activity of telomerase has been found in stem cells and cancer cells specifically, various methods have been developed for the evaluation of telomerase activity. To overcome the time-consuming procedures and complicated manipulations of existing methods, we developed a novel method named Telomeric Repeat Elongation Assay based on Quartz crystal microbalance (TREAQ) to monitor telomerase activity during the self-renewal and differentiation of human induced pluripotent stem cells (hiPSCs). TREAQ results indicated hiPSCs possess invariable telomerase activity for 11 passages on Matrigel and a steady decline of telomerase activity when differentiated for different periods, which is confirmed with existing golden standard method. The pluripotency of hiPSCs during differentiation could be estimated through monitoring telomerase activity and compared with the expression levels of markers of pluripotency gene via quantitative real time PCR. Regular assessment for factors associated with pluripotency or stemness was expensive and requires excessive sample consuming, thus TREAQ could be a promising alternative technology for routine monitoring of telomerase activity and estimate the pluripotency of stem cells.

  12. Four-Parameter white blood cell differential counting based on light scattering measurements

    NARCIS (Netherlands)

    Terstappen, Leonardus Wendelinus Mathias Marie; de Grooth, B.G.; Visscher, K.; Kouterik, F.A.; Greve, Jan

    1988-01-01

    Measurement of the depolarized orthogonal light scattering in flow cytometry enables one to discriminate human eosinephilic granulocytes from neutrophilic granulocytes. We use this method to perform a four-parameter differential white blood cell analysis. A simple flow cytometer was built equipped

  13. Quantum hydrodynamics and nonlinear differential equations for degenerate Fermi gas

    International Nuclear Information System (INIS)

    Bettelheim, Eldad; Abanov, Alexander G; Wiegmann, Paul B

    2008-01-01

    We present new nonlinear differential equations for spacetime correlation functions of Fermi gas in one spatial dimension. The correlation functions we consider describe non-stationary processes out of equilibrium. The equations we obtain are integrable equations. They generalize known nonlinear differential equations for correlation functions at equilibrium [1-4] and provide vital tools for studying non-equilibrium dynamics of electronic systems. The method we developed is based only on Wick's theorem and the hydrodynamic description of the Fermi gas. Differential equations appear directly in bilinear form. (fast track communication)

  14. Differential effects of stress-induced cortisol responses on recollection and familiarity-based recognition memory.

    Science.gov (United States)

    McCullough, Andrew M; Ritchey, Maureen; Ranganath, Charan; Yonelinas, Andrew

    2015-09-01

    Stress-induced changes in cortisol can impact memory in various ways. However, the precise relationship between cortisol and recognition memory is still poorly understood. For instance, there is reason to believe that stress could differentially affect recollection-based memory, which depends on the hippocampus, and familiarity-based recognition, which can be supported by neocortical areas alone. Accordingly, in the current study we examined the effects of stress-related changes in cortisol on the processes underlying recognition memory. Stress was induced with a cold-pressor test after incidental encoding of emotional and neutral pictures, and recollection and familiarity-based recognition memory were measured one day later. The relationship between stress-induced cortisol responses and recollection was non-monotonic, such that subjects with moderate stress-related increases in cortisol had the highest levels of recollection. In contrast, stress-related cortisol responses were linearly related to increases in familiarity. In addition, measures of cortisol taken at the onset of the experiment showed that individuals with higher levels of pre-learning cortisol had lower levels of both recollection and familiarity. The results are consistent with the proposition that hippocampal-dependent memory processes such as recollection function optimally under moderate levels of stress, whereas more cortically-based processes such as familiarity are enhanced even with higher levels of stress. These results indicate that whether post-encoding stress improves or disrupts recognition memory depends on the specific memory process examined as well as the magnitude of the stress-induced cortisol response. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. International Conference on Differential Equations and Nonlinear Mechanics

    CERN Document Server

    2001-01-01

    The International Conference on Differential Equations and Nonlinear Mechanics was hosted by the University of Central Florida in Orlando from March 17-19, 1999. One of the conference days was dedicated to Professor V. Lakshmikantham in th honor of his 75 birthday. 50 well established professionals (in differential equations, nonlinear analysis, numerical analysis, and nonlinear mechanics) attended the conference from 13 countries. Twelve of the attendees delivered hour long invited talks and remaining thirty-eight presented invited forty-five minute talks. In each of these talks, the focus was on the recent developments in differential equations and nonlinear mechanics and their applications. This book consists of 29 papers based on the invited lectures, and I believe that it provides a good selection of advanced topics of current interest in differential equations and nonlinear mechanics. I am indebted to the Department of Mathematics, College of Arts and Sciences, Department of Mechanical, Materials and Ae...

  16. The Earnings Differential between Formal and Informal Employees in Urban China

    Directory of Open Access Journals (Sweden)

    Hong Zuo

    2013-10-01

    Full Text Available Few studies in the field of labor economics have analyzed the earnings differential between formal and informal employees in urban China. Due to data limitations, previous studies on this subject have not yielded accurate and widely acceptable results. This study seeks to obtain more accurate results by analyzing the earnings differential based on the conceptual framework of informal employment developed by the 17th International Conference of Labor Statisticians. We analyzed data from the 2006 Chinese General Social Survey, using the Lee model to correct for selection bias and decomposing the earnings differential between formal and informal employees in urban China in terms of the effects of employee characteristics, employment, and working hours. The latter two of these comprise the segmentation effect. We found that only 33% of the observed earnings differential can be explained by employee characteristics; the remaining 67% is attributable to the segmentation effect. The working hours effect narrows the earnings differential. Based on the results of our analysis, we conclude that informal employees in urban China, especially female informal employees, suffer from segmentation and that policies to address segmentation issues are needed.

  17. Samples of noncommutative products in certain differential equations

    International Nuclear Information System (INIS)

    Legare, M

    2010-01-01

    A set of associative noncommutative products is considered in different differential equations of the ordinary and partial types. A method of separation of variables is considered for a large set of those systems. The products involved include for example some * products and some products based on Nijenhuis tensors, which are embedded in the differential equations of the Laplace/Poisson, Lax and Schroedinger styles. A comment on the *-products of Reshetikhin-Jambor-Sykora type is also given in relation to *-products of Vey type.

  18. Application of the Generalized Differential Quadrature Method in Solving Burgers' Equations

    International Nuclear Information System (INIS)

    Mokhtari, R.; Toodar, A. Samadi; Chegini, N.G.

    2011-01-01

    The aim of this paper is to obtain numerical solutions of the one-dimensional, two-dimensional and coupled Burgers' equations through the generalized differential quadrature method (GDQM). The polynomial-based differential quadrature (PDQ) method is employed and the obtained system of ordinary differential equations is solved via the total variation diminishing Runge-Kutta (TVD-RK) method. The numerical solutions are satisfactorily coincident with the exact solutions. The method can compete against the methods applied in the literature. (general)

  19. Hojman's theorem of the third-order ordinary differential equation

    International Nuclear Information System (INIS)

    Hong-Sheng, Lü; Hong-Bin, Zhang; Shu-Long, Gu

    2009-01-01

    This paper extends Hojman's conservation law to the third-order differential equation. A new conserved quantity is constructed based on the Lie group of transformation generators of the equations of motion. The generators contain variations of the time and generalized coordinates. Two independent non-trivial conserved quantities of the third-order ordinary differential equation are obtained. A simple example is presented to illustrate the applications of the results. (general)

  20. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATHEMATICA based packages for differential reduction of generalized hypergeometric functions {sub p}F{sub p-1}, F{sub 1}, F{sub 2}, F{sub 3}, F{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Joint Institute for Nuclear Research, Dubna (Russian Federation); Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-05-15

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions {sub p+1}F{sub p}, and the second one, AppellF1F4, for manipulations with Appell hypergeometric functions F{sub 1}, F{sub 2}, F{sub 3}, F{sub 4} of two variables.

  1. Kernel Clustering with a Differential Harmony Search Algorithm for Scheme Classification

    Directory of Open Access Journals (Sweden)

    Yu Feng

    2017-01-01

    Full Text Available This paper presents a kernel fuzzy clustering with a novel differential harmony search algorithm to coordinate with the diversion scheduling scheme classification. First, we employed a self-adaptive solution generation strategy and differential evolution-based population update strategy to improve the classical harmony search. Second, we applied the differential harmony search algorithm to the kernel fuzzy clustering to help the clustering method obtain better solutions. Finally, the combination of the kernel fuzzy clustering and the differential harmony search is applied for water diversion scheduling in East Lake. A comparison of the proposed method with other methods has been carried out. The results show that the kernel clustering with the differential harmony search algorithm has good performance to cooperate with the water diversion scheduling problems.

  2. Hybrid Differential Dynamic Programming with Stochastic Search

    Science.gov (United States)

    Aziz, Jonathan; Parker, Jeffrey; Englander, Jacob

    2016-01-01

    Differential dynamic programming (DDP) has been demonstrated as a viable approach to low-thrust trajectory optimization, namely with the recent success of NASAs Dawn mission. The Dawn trajectory was designed with the DDP-based Static Dynamic Optimal Control algorithm used in the Mystic software. Another recently developed method, Hybrid Differential Dynamic Programming (HDDP) is a variant of the standard DDP formulation that leverages both first-order and second-order state transition matrices in addition to nonlinear programming (NLP) techniques. Areas of improvement over standard DDP include constraint handling, convergence properties, continuous dynamics, and multi-phase capability. DDP is a gradient based method and will converge to a solution nearby an initial guess. In this study, monotonic basin hopping (MBH) is employed as a stochastic search method to overcome this limitation, by augmenting the HDDP algorithm for a wider search of the solution space.

  3. Algorithmic Verification of Linearizability for Ordinary Differential Equations

    KAUST Repository

    Lyakhov, Dmitry A.

    2017-07-19

    For a nonlinear ordinary differential equation solved with respect to the highest order derivative and rational in the other derivatives and in the independent variable, we devise two algorithms to check if the equation can be reduced to a linear one by a point transformation of the dependent and independent variables. The first algorithm is based on a construction of the Lie point symmetry algebra and on the computation of its derived algebra. The second algorithm exploits the differential Thomas decomposition and allows not only to test the linearizability, but also to generate a system of nonlinear partial differential equations that determines the point transformation and the coefficients of the linearized equation. The implementation of both algorithms is discussed and their application is illustrated using several examples.

  4. Nonlinear differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Dresner, L.

    1988-01-01

    This report is the text of a graduate course on nonlinear differential equations given by the author at the University of Wisconsin-Madison during the summer of 1987. The topics covered are: direction fields of first-order differential equations; the Lie (group) theory of ordinary differential equations; similarity solutions of second-order partial differential equations; maximum principles and differential inequalities; monotone operators and iteration; complementary variational principles; and stability of numerical methods. The report should be of interest to graduate students, faculty, and practicing scientists and engineers. No prior knowledge is required beyond a good working knowledge of the calculus. The emphasis is on practical results. Most of the illustrative examples are taken from the fields of nonlinear diffusion, heat and mass transfer, applied superconductivity, and helium cryogenics.

  5. Nonlinear differential equations

    International Nuclear Information System (INIS)

    Dresner, L.

    1988-01-01

    This report is the text of a graduate course on nonlinear differential equations given by the author at the University of Wisconsin-Madison during the summer of 1987. The topics covered are: direction fields of first-order differential equations; the Lie (group) theory of ordinary differential equations; similarity solutions of second-order partial differential equations; maximum principles and differential inequalities; monotone operators and iteration; complementary variational principles; and stability of numerical methods. The report should be of interest to graduate students, faculty, and practicing scientists and engineers. No prior knowledge is required beyond a good working knowledge of the calculus. The emphasis is on practical results. Most of the illustrative examples are taken from the fields of nonlinear diffusion, heat and mass transfer, applied superconductivity, and helium cryogenics

  6. Evaluation of a Cubature Kalman Filtering-Based Phase Unwrapping Method for Differential Interferograms with High Noise in Coal Mining Areas

    Directory of Open Access Journals (Sweden)

    Wanli Liu

    2015-07-01

    Full Text Available Differential interferometric synthetic aperture radar has been shown to be effective for monitoring subsidence in coal mining areas. Phase unwrapping can have a dramatic influence on the monitoring result. In this paper, a filtering-based phase unwrapping algorithm in combination with path-following is introduced to unwrap differential interferograms with high noise in mining areas. It can perform simultaneous noise filtering and phase unwrapping so that the pre-filtering steps can be omitted, thus usually retaining more details and improving the detectable deformation. For the method, the nonlinear measurement model of phase unwrapping is processed using a simplified Cubature Kalman filtering, which is an effective and efficient tool used in many nonlinear fields. Three case studies are designed to evaluate the performance of the method. In Case 1, two tests are designed to evaluate the performance of the method under different factors including the number of multi-looks and path-guiding indexes. The result demonstrates that the unwrapped results are sensitive to the number of multi-looks and that the Fisher Distance is the most suitable path-guiding index for our study. Two case studies are then designed to evaluate the feasibility of the proposed phase unwrapping method based on Cubature Kalman filtering. The results indicate that, compared with the popular Minimum Cost Flow method, the Cubature Kalman filtering-based phase unwrapping can achieve promising results without pre-filtering and is an appropriate method for coal mining areas with high noise.

  7. Microarray-based analysis of the differential expression of melanin synthesis genes in dark and light-muzzle Korean cattle.

    Science.gov (United States)

    Kim, Sang Hwan; Hwang, Sue Yun; Yoon, Jong Taek

    2014-01-01

    The coat color of mammals is determined by the melanogenesis pathway, which is responsible for maintaining the balance between black-brown eumelanin and yellow-reddish pheomelanin. It is also believed that the color of the bovine muzzle is regulated in a similar manner; however, the molecular mechanism underlying pigment deposition in the dark-muzzle has yet to be elucidated. The aim of the present study was to identify melanogenesis-associated genes that are differentially expressed in the dark vs. light muzzle of native Korean cows. Using microarray clustering and real-time polymerase chain reaction techniques, we observed that the expression of genes involved in the mitogen-activated protein kinase (MAPK) and Wnt signaling pathways is distinctively regulated in the dark and light muzzle tissues. Differential expression of tyrosinase was also noticed, although the difference was not as distinct as those of MAPK and Wnt. We hypothesize that emphasis on the MAPK pathway in the dark-muzzle induces eumelanin synthesis through the activation of cAMP response element-binding protein and tyrosinase, while activation of Wnt signaling counteracts this process and raises the amount of pheomelanin in the light-muzzle. We also found 2 novel genes (GenBank No. NM-001076026 and XM-588439) with increase expression in the black nose, which may provide additional information about the mechanism of nose pigmentation. Regarding the increasing interest in the genetic diversity of cattle stocks, genes we identified for differential expression in the dark vs. light muzzle may serve as novel markers for genetic diversity among cows based on the muzzle color phenotype.

  8. Microarray-based analysis of the differential expression of melanin synthesis genes in dark and light-muzzle Korean cattle.

    Directory of Open Access Journals (Sweden)

    Sang Hwan Kim

    Full Text Available The coat color of mammals is determined by the melanogenesis pathway, which is responsible for maintaining the balance between black-brown eumelanin and yellow-reddish pheomelanin. It is also believed that the color of the bovine muzzle is regulated in a similar manner; however, the molecular mechanism underlying pigment deposition in the dark-muzzle has yet to be elucidated. The aim of the present study was to identify melanogenesis-associated genes that are differentially expressed in the dark vs. light muzzle of native Korean cows. Using microarray clustering and real-time polymerase chain reaction techniques, we observed that the expression of genes involved in the mitogen-activated protein kinase (MAPK and Wnt signaling pathways is distinctively regulated in the dark and light muzzle tissues. Differential expression of tyrosinase was also noticed, although the difference was not as distinct as those of MAPK and Wnt. We hypothesize that emphasis on the MAPK pathway in the dark-muzzle induces eumelanin synthesis through the activation of cAMP response element-binding protein and tyrosinase, while activation of Wnt signaling counteracts this process and raises the amount of pheomelanin in the light-muzzle. We also found 2 novel genes (GenBank No. NM-001076026 and XM-588439 with increase expression in the black nose, which may provide additional information about the mechanism of nose pigmentation. Regarding the increasing interest in the genetic diversity of cattle stocks, genes we identified for differential expression in the dark vs. light muzzle may serve as novel markers for genetic diversity among cows based on the muzzle color phenotype.

  9. HIF-1α as a Regulator of BMP2-Induced Chondrogenic Differentiation, Osteogenic Differentiation, and Endochondral Ossification in Stem Cells

    Directory of Open Access Journals (Sweden)

    Nian Zhou

    2015-04-01

    Full Text Available Background/Aims: Joint cartilage defects are difficult to treat due to the limited self-repair capacities of cartilage. Cartilage tissue engineering based on stem cells and gene enhancement is a potential alternative for cartilage repair. Bone morphogenetic protein 2 (BMP2 has been shown to induce chondrogenic differentiation in mesenchymal stem cells (MSCs; however, maintaining the phenotypes of MSCs during cartilage repair since differentiation occurs along the endochondral ossification pathway. In this study, hypoxia inducible factor, or (HIF-1α, was determined to be a regulator of BMP2-induced chondrogenic differentiation, osteogenic differentiation, and endochondral bone formation. Methods: BMP2 was used to induce chondrogenic and osteogenic differentiation in stem cells and fetal limb development. After HIF-1α was added to the inducing system, any changes in the differentiation markers were assessed. Results: HIF-1α was found to potentiate BMP2-induced Sox9 and the expression of chondrogenesis by downstream markers, and inhibit Runx2 and the expression of osteogenesis by downstream markers in vitro. In subcutaneous stem cell implantation studies, HIF-1α was shown to potentiate BMP2-induced cartilage formation and inhibit endochondral ossification during ectopic bone/cartilage formation. In the fetal limb culture, HIF-1α and BMP2 synergistically promoted the expansion of the proliferating chondrocyte zone and inhibited chondrocyte hypertrophy and endochondral ossification. Conclusion: The results of this study indicated that, when combined with BMP2, HIF-1α induced MSC differentiation could become a new method of maintaining cartilage phenotypes during cartilage tissue engineering.

  10. Differential diagnosis of Raynaud’s phenomenon based on modeling of finger thermoregulation

    International Nuclear Information System (INIS)

    Ismail, E; Romani, G L; Merla, A; Orlando, G; Corradini, M L; Amerio, P

    2014-01-01

    Raynaud's phenomenon (RP) is a vasospastic disorder of small arteries, pre-capillary arteries, and cutaneous arteriovenous shunts of the extremities, typically induced by cold exposure and emotional stress. RP is either primary (PRP) or secondary to connective tissue diseases such as systemic sclerosis (SSc). Early differential diagnosis is crucial in order to set the proper therapeutic strategy. To this goal, thermal infrared imaging data from 18 healthy controls (HCs) and 48 RP patients (20 PRP, 28 SSc) were processed through a model for a second-order time-invariant system with exponential critically damped dynamic response. Subject classification on the basis of the model parameters provides 100% true-positive discrimination for RP patients (PRP and SSc) and healthy, and 90% of correct classification within the group of patients. The proposed method may provide useful hints for early differential diagnosis in the assessment of RP disease. (paper)

  11. Using Technology to Facilitate Differentiated High School Science Instruction

    Science.gov (United States)

    Maeng, Jennifer L.

    2017-10-01

    This qualitative investigation explored the beliefs and practices of one secondary science teacher, Diane, who differentiated instruction and studied how technology facilitated her differentiation. Diane was selected based on the results of a previous study, in which data indicated that Diane understood how to design and implement proactively planned, flexible, engaging instructional activities in response to students' learning needs better than the other study participants. Data for the present study included 3 h of semi-structured interview responses, 37.5 h of observations of science instruction, and other artifacts such as instructional materials. This variety of data allowed for triangulation of the evidence. Data were analyzed using a constant comparative approach. Results indicated that technology played an integral role in Diane's planning and implementation of differentiated science lessons. The technology-enhanced differentiated lessons employed by Diane typically attended to students' different learning profiles or interest through modification of process or product. This study provides practical strategies for science teachers beginning to differentiate instruction, and recommendations for science teacher educators and school and district administrators. Future research should explore student outcomes, supports for effective formative assessment, and technology-enhanced readiness differentiation among secondary science teachers.

  12. A novel method to solve functional differential equations

    International Nuclear Information System (INIS)

    Tapia, V.

    1990-01-01

    A method to solve differential equations containing the variational operator as the derivation operation is presented. They are called variational differential equations (VDE). The solution to a VDE should be a function containing the derivatives, with respect to the base space coordinates, of the fields up to a generic order s: a s-th-order function. The variational operator doubles the order of the function on which it acts. Therefore, in order to make compatible the orders of the different terms appearing in a VDE, the solution should be a function containing the derivatives of the fields at all orders. But this takes us again back to the functional methods. In order to avoid this, one must restrict the considerations, in the case of second-order VDEs, to the space of s-th-order functions on which the variational operator acts transitively. These functions have been characterized for a one-dimensional base space for the first- and second-order cases. These functions turn out to be polynomial in the highest-order derivatives of the fields with functions of the lower-order derivatives as coefficients. Then VDEs reduce to a system of coupled partial differential equations for the coefficients above mentioned. The importance of the method lies on the fact that the solutions to VDEs are in a one-to-one correspondence with the solutions of functional differential equations. The previous method finds direct applications in quantum field theory, where the Schroedinger equation plays a central role. Since the Schroedinger equation is reduced to a system of coupled partial differential equations, this provides a nonperturbative scheme for quantum field theory. As an example, the massless scalar field is considered

  13. A study on an automated computerized differential diagnosis of diffuse liver diseases, based only on hepatic scintigrams using sup(99m)Tc-Sn-colloid

    International Nuclear Information System (INIS)

    Matsuo, Michimasa; Fujii, Susumu; Kaneda, Yukio

    1980-01-01

    Hepatic scintigrams using sup(99m)Tc-compounds are now routinely performed. In this study, automated computerized pattern characterizations of right lateral hepatic scintigrams using sup(99m)Tc-Sn colloid were studied to extract characteristic indicators, which are effective for an automated computerized differential diagnosis. The program, developed by us, of the automated computerized pattern characterization and the automated computerized differential diagnosis can be performed without the aid of professional doctors' ability of pattern recognition. The right lateral hepatic scintigrams of fifty one cases, which are accurately diagnosed by biopsy, are applied as the training group. The results of the automated computerized differential diagnosis were as follows: Three cases were accurately diagnosed among 3 normal cases; Three among 3 acute hepatitis; Seven among 7 chronic inactive hepatitis; Twenty among 22 chronic active hepatitis; Sixteen among 16 liver cirrhosis. Only two cases of chronic active hepatitis are falsely-diagnosed as chronic inactive hepatitis and as liver cirrhosis respectively. The over all accuracy rate was 96% in the training group. With this result, the automated computerized differential diagnosis of diffuse liver diseases is suggested to be possible, based on the hepatic scintigram. (author)

  14. Competitive differentiation through brand extensions in the era of hyper competition

    Directory of Open Access Journals (Sweden)

    Claudiu-Catalin Munteanu

    2015-03-01

    Full Text Available In the era of hyper competition, competitive differentiation has become increasingly important. Brand extensions are used by companies across various industries for competitive differentiation. But in the era of hyper competition, a successful differentiation strategy requires that a brand emphasizes on uniqueness rather than commoditization. In this article, we make a case for creating a meaningful differentiation strategy. We emphasize the role of brand extensions for competitive differentiation and highlight the main perils of using brand extensions as a primary differentiation strategy. By using qualitative research, we identify primary objectives for brand extensions in practice. This investigation uses in-depth interviews with 14 senior brand managers across various industries to highlight brand portfolio strategies in relation to the brand differentiation strategy. Findings reveal that for business at the base of the pyramid, in markets such as Romania, brand managers are using brand extensions to increase sales or to boost short-term revenue rather than to implement a coherent differentiation strategy. We conclude with multiple recommendations for improving brand extension usage as a strategic instrument for creating meaningful differentiation in the era of hyper competition.

  15. Interregional income differentials and migration: their interrelationships.

    Science.gov (United States)

    Tabuchi, T

    1988-02-01

    "The major objective of this paper is to demonstrate that interregional income differential is exogenous to interregional net migration, but not conversely. Utilizing Japanese prefectural-based data for 1954-82, we conduct the following three kinds of analyses to confirm this statement. Firstly, a simple comparison of the crests of interregional time-series plots was made to see which occurred first. Secondly, Sims', 1972, test of causality was done to investigate causation between urban/rural income differential and net migration. Finally, per capita income and population share were examined by two-dimensional phase diagram for nine regions." (SUMMARY IN FRE AND GER) excerpt

  16. Lymphatic filarial species differentiation using evolutionarily modified tandem repeats: generation of new genetic markers.

    Science.gov (United States)

    Sakthidevi, Moorthy; Murugan, Vadivel; Hoti, Sugeerappa Laxmanappa; Kaliraj, Perumal

    2010-05-01

    Polymerase chain reaction based methods are promising tools for the monitoring and evaluation of the Global Program for the Elimination of Lymphatic Filariasis. The currently available PCR methods do not differentiate the DNA of Wuchereria bancrofti or Brugia malayi by a single PCR and hence are cumbersome. Therefore, we designed a single step PCR strategy for differentiating Bancroftian infection from Brugian infection based on a newly identified gene from the W. bancrofti genome, abundant larval transcript-2 (alt-2), which is abundantly expressed. The difference in PCR product sizes generated from the presence or absence of evolutionarily altered tandem repeats in alt-2 intron-3 differentiated W. bancrofti from B. malayi. The analysis was performed on the genomic DNA of microfilariae from a number of patient blood samples or microfilariae positive slides from different Indian geographical regions. The assay gave consistent results, differentiating the two filarial parasite species accurately. This alt-2 intron-3 based PCR assay can be a potential tool for the diagnosis and differentiation of co-infections by lymphatic filarial parasites. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  17. High-throughput gene expression profiling of memory differentiation in primary human T cells

    Directory of Open Access Journals (Sweden)

    Russell Kate

    2008-08-01

    Full Text Available Abstract Background The differentiation of naive T and B cells into memory lymphocytes is essential for immunity to pathogens. Therapeutic manipulation of this cellular differentiation program could improve vaccine efficacy and the in vitro expansion of memory cells. However, chemical screens to identify compounds that induce memory differentiation have been limited by 1 the lack of reporter-gene or functional assays that can distinguish naive and memory-phenotype T cells at high throughput and 2 a suitable cell-line representative of naive T cells. Results Here, we describe a method for gene-expression based screening that allows primary naive and memory-phenotype lymphocytes to be discriminated based on complex genes signatures corresponding to these differentiation states. We used ligation-mediated amplification and a fluorescent, bead-based detection system to quantify simultaneously 55 transcripts representing naive and memory-phenotype signatures in purified populations of human T cells. The use of a multi-gene panel allowed better resolution than any constituent single gene. The method was precise, correlated well with Affymetrix microarray data, and could be easily scaled up for high-throughput. Conclusion This method provides a generic solution for high-throughput differentiation screens in primary human T cells where no single-gene or functional assay is available. This screening platform will allow the identification of small molecules, genes or soluble factors that direct memory differentiation in naive human lymphocytes.

  18. Optimal Decision Fusion for Urban Land-Use/Land-Cover Classification Based on Adaptive Differential Evolution Using Hyperspectral and LiDAR Data

    Directory of Open Access Journals (Sweden)

    Yanfei Zhong

    2017-08-01

    Full Text Available Hyperspectral images and light detection and ranging (LiDAR data have, respectively, the high spectral resolution and accurate elevation information required for urban land-use/land-cover (LULC classification. To combine the respective advantages of hyperspectral and LiDAR data, this paper proposes an optimal decision fusion method based on adaptive differential evolution, namely ODF-ADE, for urban LULC classification. In the ODF-ADE framework the normalized difference vegetation index (NDVI, gray-level co-occurrence matrix (GLCM and digital surface model (DSM are extracted to form the feature map. The three different classifiers of the maximum likelihood classifier (MLC, support vector machine (SVM and multinomial logistic regression (MLR are used to classify the extracted features. To find the optimal weights for the different classification maps, weighted voting is used to obtain the classification result and the weights of each classification map are optimized by the differential evolution algorithm which uses a self-adaptive strategy to obtain the parameter adaptively. The final classification map is obtained after post-processing based on conditional random fields (CRF. The experimental results confirm that the proposed algorithm is very effective in urban LULC classification.

  19. Efficient Estimating Functions for Stochastic Differential Equations

    DEFF Research Database (Denmark)

    Jakobsen, Nina Munkholt

    The overall topic of this thesis is approximate martingale estimating function-based estimationfor solutions of stochastic differential equations, sampled at high frequency. Focuslies on the asymptotic properties of the estimators. The first part of the thesis deals with diffusions observed over...

  20. Differential Game for a Class of Warfare Dynamic Systems with Reinforcement Based on Lanchester Equation

    OpenAIRE

    Chen, Xiangyong; Qiu, Jianlong

    2014-01-01

    This paper concerns the optimal reinforcement game problem between two opposing forces in military conflicts. With some moderate assumptions, we employ Lanchester equation and differential game theory to develop a corresponding optimization game model. After that, we establish the optimum condition for the differential game problem and give an algorithm to obtain the optimal reinforcement strategies. Furthermore, we also discuss the convergence of the algorithm. Finally, a numerical example i...

  1. A Bayesian approach to estimating hidden variables as well as missing and wrong molecular interactions in ordinary differential equation-based mathematical models.

    Science.gov (United States)

    Engelhardt, Benjamin; Kschischo, Maik; Fröhlich, Holger

    2017-06-01

    Ordinary differential equations (ODEs) are a popular approach to quantitatively model molecular networks based on biological knowledge. However, such knowledge is typically restricted. Wrongly modelled biological mechanisms as well as relevant external influence factors that are not included into the model are likely to manifest in major discrepancies between model predictions and experimental data. Finding the exact reasons for such observed discrepancies can be quite challenging in practice. In order to address this issue, we suggest a Bayesian approach to estimate hidden influences in ODE-based models. The method can distinguish between exogenous and endogenous hidden influences. Thus, we can detect wrongly specified as well as missed molecular interactions in the model. We demonstrate the performance of our Bayesian dynamic elastic-net with several ordinary differential equation models from the literature, such as human JAK-STAT signalling, information processing at the erythropoietin receptor, isomerization of liquid α -Pinene, G protein cycling in yeast and UV-B triggered signalling in plants. Moreover, we investigate a set of commonly known network motifs and a gene-regulatory network. Altogether our method supports the modeller in an algorithmic manner to identify possible sources of errors in ODE-based models on the basis of experimental data. © 2017 The Author(s).

  2. Myogenic Differentiation Potential of Human Newborn Foreskin Stem Cells Combined with Polycaprolactone-Based Nanofiber

    Directory of Open Access Journals (Sweden)

    Ozge Sezin Somuncu

    2016-03-01

    Full Text Available A previous study performed by the authors of the current study revealed the characterization and differentiation of newly defined stem cells known as human newborn foreskin stem cells (hnFSSCs. According to their stem cell properties, this study aimed at investigating myogenic differentiation and related tissue engineering. Human newborn foreskin stem cells were characterized by flow cytometry. The results showed that hnFSSCs carries a noble prospective for myogenic differentiation and can be used as a beneficial method for muscle related diseases, including muscular dystrophy, neuromuscular disorders, muscle damages, muscle weakness, lesion formations, and other problems associated with tissue obtainability and multi-potency; these cells may be accepted as effortlessly accessible and functional, and even superior to other stem cell origins. Furthermore, hnFFSCs were also seeded onto 3D micro-wells and Polycaprolactone (PCL scaffolds in order to examine tissue development. Human newborn foreskin stem cells on PCL scaffolds showed good cell-cell integration, so that they may be thought as a stem cell basis for tissue engineering.

  3. Radiomics-based differentiation of lung disease models generated by polluted air based on X-ray computed tomography data.

    Science.gov (United States)

    Szigeti, Krisztián; Szabó, Tibor; Korom, Csaba; Czibak, Ilona; Horváth, Ildikó; Veres, Dániel S; Gyöngyi, Zoltán; Karlinger, Kinga; Bergmann, Ralf; Pócsik, Márta; Budán, Ferenc; Máthé, Domokos

    2016-02-11

    Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann-Whitney post hoc (MWph) tests were used. Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas.

  4. Differential Evolution Based IDWNN Controller for Fault Ride-Through of Grid-Connected Doubly Fed Induction Wind Generators.

    Science.gov (United States)

    Manonmani, N; Subbiah, V; Sivakumar, L

    2015-01-01

    The key objective of wind turbine development is to ensure that output power is continuously increased. It is authenticated that wind turbines (WTs) supply the necessary reactive power to the grid at the time of fault and after fault to aid the flowing grid voltage. At this juncture, this paper introduces a novel heuristic based controller module employing differential evolution and neural network architecture to improve the low-voltage ride-through rate of grid-connected wind turbines, which are connected along with doubly fed induction generators (DFIGs). The traditional crowbar-based systems were basically applied to secure the rotor-side converter during the occurrence of grid faults. This traditional controller is found not to satisfy the desired requirement, since DFIG during the connection of crowbar acts like a squirrel cage module and absorbs the reactive power from the grid. This limitation is taken care of in this paper by introducing heuristic controllers that remove the usage of crowbar and ensure that wind turbines supply necessary reactive power to the grid during faults. The controller is designed in this paper to enhance the DFIG converter during the grid fault and this controller takes care of the ride-through fault without employing any other hardware modules. The paper introduces a double wavelet neural network controller which is appropriately tuned employing differential evolution. To validate the proposed controller module, a case study of wind farm with 1.5 MW wind turbines connected to a 25 kV distribution system exporting power to a 120 kV grid through a 30 km 25 kV feeder is carried out by simulation.

  5. Differential Evolution Based IDWNN Controller for Fault Ride-Through of Grid-Connected Doubly Fed Induction Wind Generators

    Directory of Open Access Journals (Sweden)

    N. Manonmani

    2015-01-01

    Full Text Available The key objective of wind turbine development is to ensure that output power is continuously increased. It is authenticated that wind turbines (WTs supply the necessary reactive power to the grid at the time of fault and after fault to aid the flowing grid voltage. At this juncture, this paper introduces a novel heuristic based controller module employing differential evolution and neural network architecture to improve the low-voltage ride-through rate of grid-connected wind turbines, which are connected along with doubly fed induction generators (DFIGs. The traditional crowbar-based systems were basically applied to secure the rotor-side converter during the occurrence of grid faults. This traditional controller is found not to satisfy the desired requirement, since DFIG during the connection of crowbar acts like a squirrel cage module and absorbs the reactive power from the grid. This limitation is taken care of in this paper by introducing heuristic controllers that remove the usage of crowbar and ensure that wind turbines supply necessary reactive power to the grid during faults. The controller is designed in this paper to enhance the DFIG converter during the grid fault and this controller takes care of the ride-through fault without employing any other hardware modules. The paper introduces a double wavelet neural network controller which is appropriately tuned employing differential evolution. To validate the proposed controller module, a case study of wind farm with 1.5 MW wind turbines connected to a 25 kV distribution system exporting power to a 120 kV grid through a 30 km 25 kV feeder is carried out by simulation.

  6. Existence of a coupled system of fractional differential equations

    International Nuclear Information System (INIS)

    Ibrahim, Rabha W.; Siri, Zailan

    2015-01-01

    We manage the existence and uniqueness of a fractional coupled system containing Schrödinger equations. Such a system appears in quantum mechanics. We confirm that the fractional system under consideration admits a global solution in appropriate functional spaces. The solution is shown to be unique. The method is based on analytic technique of the fixed point theory. The fractional differential operator is considered from the virtue of the Riemann-Liouville differential operator

  7. Existence of a coupled system of fractional differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Rabha W. [Multimedia unit, Department of Computer System and Technology Faculty of Computer Science & IT, University of Malaya, 50603 Kuala Lumpur (Malaysia); Siri, Zailan [Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-10-22

    We manage the existence and uniqueness of a fractional coupled system containing Schrödinger equations. Such a system appears in quantum mechanics. We confirm that the fractional system under consideration admits a global solution in appropriate functional spaces. The solution is shown to be unique. The method is based on analytic technique of the fixed point theory. The fractional differential operator is considered from the virtue of the Riemann-Liouville differential operator.

  8. Partial Differential Equations

    CERN Document Server

    1988-01-01

    The volume contains a selection of papers presented at the 7th Symposium on differential geometry and differential equations (DD7) held at the Nankai Institute of Mathematics, Tianjin, China, in 1986. Most of the contributions are original research papers on topics including elliptic equations, hyperbolic equations, evolution equations, non-linear equations from differential geometry and mechanics, micro-local analysis.

  9. Starvation Based Differential Chemotherapy: A Novel Approach for Cancer Treatment

    Directory of Open Access Journals (Sweden)

    Sidra Naveed

    2014-11-01

    Full Text Available Cancer patients undergoing chemotherapy treatment are advised to increase food intake to overcome the therapy-induced side effects, and weight loss. Dietary restriction is known to slow down the aging process and hence reduce age-related diseases such as cancer. Fasting or short-term starvation is more effective than dietary restriction to prevent cancer growth since starved cells switch off signals for growth and reproduction and enter a protective mode, while cancer cells, being mutated, are not sensitized by any external growth signals and are not protected against any stress. This phenomenon is known as differential stress resistance (DSR. Nutrient signaling pathways involving growth hormone/insulin-like growth factor-1 axis and its downstream effectors, play a key role in DSR in response to starvation controlling the other cell maintenance systems, such as autophagy and apoptosis, that are related to the tumorigenesis. Yeast cells lacking these effectors are better protected against oxidative stress compared to normal cells. In the same way, starvation protects many cell lines and mice against high-dose chemotherapeutic drugs. According to a series of studies, fasting results in overall reduction in chemotherapy side effects in cancer patients. Data shows that starvation-dependent differential chemotherapy is safe, feasible and effective in cancer treatment, but the possible side effects of starvation limit its efficacy. However, further studies and clinical trials may result in its implementation in cancer treatment.

  10. Analysis of pharmacogenomic variants associated with population differentiation.

    Directory of Open Access Journals (Sweden)

    Bora Yeon

    Full Text Available In the present study, we systematically investigated population differentiation of drug-related (DR genes in order to identify common genetic features underlying population-specific responses to drugs. To do so, we used the International HapMap project release 27 Data and Pharmacogenomics Knowledge Base (PharmGKB database. First, we compared four measures for assessing population differentiation: the chi-square test, the analysis of variance (ANOVA F-test, Fst, and Nearest Shrunken Centroid Method (NSCM. Fst showed high sensitivity with stable specificity among varying sample sizes; thus, we selected Fst for determining population differentiation. Second, we divided DR genes from PharmGKB into two groups based on the degree of population differentiation as assessed by Fst: genes with a high level of differentiation (HD gene group and genes with a low level of differentiation (LD gene group. Last, we conducted a gene ontology (GO analysis and pathway analysis. Using all genes in the human genome as the background, the GO analysis and pathway analysis of the HD genes identified terms related to cell communication. "Cell communication" and "cell-cell signaling" had the lowest Benjamini-Hochberg's q-values (0.0002 and 0.0006, respectively, and "drug binding" was highly enriched (16.51 despite its relatively high q-value (0.0142. Among the 17 genes related to cell communication identified in the HD gene group, five genes (STX4, PPARD, DCK, GRIK4, and DRD3 contained single nucleotide polymorphisms with Fst values greater than 0.5. Specifically, the Fst values for rs10871454, rs6922548, rs3775289, rs1954787, and rs167771 were 0.682, 0.620, 0.573, 0.531, and 0.510, respectively. In the analysis using DR genes as the background, the HD gene group contained six significant terms. Five were related to reproduction, and one was "Wnt signaling pathway," which has been implicated in cancer. Our analysis suggests that the HD gene group from PharmGKB is

  11. Analysis of pharmacogenomic variants associated with population differentiation.

    Science.gov (United States)

    Yeon, Bora; Ahn, Eunyong; Kim, Kyung-Im; Kim, In-Wha; Oh, Jung Mi; Park, Taesung

    2015-01-01

    In the present study, we systematically investigated population differentiation of drug-related (DR) genes in order to identify common genetic features underlying population-specific responses to drugs. To do so, we used the International HapMap project release 27 Data and Pharmacogenomics Knowledge Base (PharmGKB) database. First, we compared four measures for assessing population differentiation: the chi-square test, the analysis of variance (ANOVA) F-test, Fst, and Nearest Shrunken Centroid Method (NSCM). Fst showed high sensitivity with stable specificity among varying sample sizes; thus, we selected Fst for determining population differentiation. Second, we divided DR genes from PharmGKB into two groups based on the degree of population differentiation as assessed by Fst: genes with a high level of differentiation (HD gene group) and genes with a low level of differentiation (LD gene group). Last, we conducted a gene ontology (GO) analysis and pathway analysis. Using all genes in the human genome as the background, the GO analysis and pathway analysis of the HD genes identified terms related to cell communication. "Cell communication" and "cell-cell signaling" had the lowest Benjamini-Hochberg's q-values (0.0002 and 0.0006, respectively), and "drug binding" was highly enriched (16.51) despite its relatively high q-value (0.0142). Among the 17 genes related to cell communication identified in the HD gene group, five genes (STX4, PPARD, DCK, GRIK4, and DRD3) contained single nucleotide polymorphisms with Fst values greater than 0.5. Specifically, the Fst values for rs10871454, rs6922548, rs3775289, rs1954787, and rs167771 were 0.682, 0.620, 0.573, 0.531, and 0.510, respectively. In the analysis using DR genes as the background, the HD gene group contained six significant terms. Five were related to reproduction, and one was "Wnt signaling pathway," which has been implicated in cancer. Our analysis suggests that the HD gene group from PharmGKB is associated with

  12. Metabolite Biometrics for the Differentiation of Individuals.

    Science.gov (United States)

    Hair, Mindy E; Mathis, Adrianna I; Brunelle, Erica K; Halámková, Lenka; Halámek, Jan

    2018-04-17

    Sweat is a biological fluid present on the skin surface of every individual and is known to contain amino acids as well as other low molecular weight compounds. (1) Each individual is inherently different from one another based on certain factors including, but not limited to, his/her genetic makeup, environment, and lifestyle. As such, the biochemical composition of each person greatly differs. The concentrations of the biochemical content within an individual's sweat are largely controlled by metabolic processes within the body that fluctuate regularly based on attributes such as age, sex, and activity level. Therefore, the concentrations of these sweat components are person-specific and can be exploited, as presented here, to differentiate individuals based on trace amounts of sweat. For this concept, we analyzed three model compounds-lactate, urea, and glutamate. The average absorbance change from each compound in sweat was determined using three separate bioaffinity-based systems: lactate oxidase coupled with horseradish peroxidase (LOx-HRP), urease coupled with glutamate dehydrogenase (UR-GlDH), and glutamate dehydrogenase alone (GlDH). After optimization of a linear dependence for each assay to its respective analyte, analysis was performed on 50 mimicked sweat samples. Additionally, a collection and extraction method was developed and optimized by our group to evaluate authentic sweat samples from the skin surface of 25 individuals. A multivariate analysis of variance (MANOVA) test was performed to demonstrate that these three single-analyte enzymatic assays were effectively used to identify each person in both sample sets. This novel sweat analysis approach is capable of differentiating individuals, without the use of DNA, based on the collective responses from the chosen metabolic compounds in sweat. Applications for this newly developed, noninvasive analysis can include the field of forensic science in order to differentiate between individuals as well

  13. Algebraic dynamics solutions and algebraic dynamics algorithm for nonlinear ordinary differential equations

    Institute of Scientific and Technical Information of China (English)

    WANG; Shunjin; ZHANG; Hua

    2006-01-01

    The problem of preserving fidelity in numerical computation of nonlinear ordinary differential equations is studied in terms of preserving local differential structure and approximating global integration structure of the dynamical system.The ordinary differential equations are lifted to the corresponding partial differential equations in the framework of algebraic dynamics,and a new algorithm-algebraic dynamics algorithm is proposed based on the exact analytical solutions of the ordinary differential equations by the algebraic dynamics method.In the new algorithm,the time evolution of the ordinary differential system is described locally by the time translation operator and globally by the time evolution operator.The exact analytical piece-like solution of the ordinary differential equations is expressd in terms of Taylor series with a local convergent radius,and its finite order truncation leads to the new numerical algorithm with a controllable precision better than Runge Kutta Algorithm and Symplectic Geometric Algorithm.

  14. Numerical models for differential problems

    CERN Document Server

    Quarteroni, Alfio

    2017-01-01

    In this text, we introduce the basic concepts for the numerical modelling of partial differential equations. We consider the classical elliptic, parabolic and hyperbolic linear equations, but also the diffusion, transport, and Navier-Stokes equations, as well as equations representing conservation laws, saddle-point problems and optimal control problems. Furthermore, we provide numerous physical examples which underline such equations. We then analyze numerical solution methods based on finite elements, finite differences, finite volumes, spectral methods and domain decomposition methods, and reduced basis methods. In particular, we discuss the algorithmic and computer implementation aspects and provide a number of easy-to-use programs. The text does not require any previous advanced mathematical knowledge of partial differential equations: the absolutely essential concepts are reported in a preliminary chapter. It is therefore suitable for students of bachelor and master courses in scientific disciplines, an...

  15. Numerical Solution of Heun Equation Via Linear Stochastic Differential Equation

    Directory of Open Access Journals (Sweden)

    Hamidreza Rezazadeh

    2014-05-01

    Full Text Available In this paper, we intend to solve special kind of ordinary differential equations which is called Heun equations, by converting to a corresponding stochastic differential equation(S.D.E.. So, we construct a stochastic linear equation system from this equation which its solution is based on computing fundamental matrix of this system and then, this S.D.E. is solved by numerically methods. Moreover, its asymptotic stability and statistical concepts like expectation and variance of solutions are discussed. Finally, the attained solutions of these S.D.E.s compared with exact solution of corresponding differential equations.

  16. A multi-domain spectral method for time-fractional differential equations

    Science.gov (United States)

    Chen, Feng; Xu, Qinwu; Hesthaven, Jan S.

    2015-07-01

    This paper proposes an approach for high-order time integration within a multi-domain setting for time-fractional differential equations. Since the kernel is singular or nearly singular, two main difficulties arise after the domain decomposition: how to properly account for the history/memory part and how to perform the integration accurately. To address these issues, we propose a novel hybrid approach for the numerical integration based on the combination of three-term-recurrence relations of Jacobi polynomials and high-order Gauss quadrature. The different approximations used in the hybrid approach are justified theoretically and through numerical examples. Based on this, we propose a new multi-domain spectral method for high-order accurate time integrations and study its stability properties by identifying the method as a generalized linear method. Numerical experiments confirm hp-convergence for both time-fractional differential equations and time-fractional partial differential equations.

  17. Hadamard-type fractional differential equations, inclusions and inequalities

    CERN Document Server

    Ahmad, Bashir; Ntouyas, Sotiris K; Tariboon, Jessada

    2017-01-01

    This book focuses on the recent development of fractional differential equations, integro-differential equations, and inclusions and inequalities involving the Hadamard derivative and integral. Through a comprehensive study based in part on their recent research, the authors address the issues related to initial and boundary value problems involving Hadamard type differential equations and inclusions as well as their functional counterparts. The book covers fundamental concepts of multivalued analysis and introduces a new class of mixed initial value problems involving the Hadamard derivative and Riemann-Liouville fractional integrals. In later chapters, the authors discuss nonlinear Langevin equations as well as coupled systems of Langevin equations with fractional integral conditions. Focused and thorough, this book is a useful resource for readers and researchers interested in the area of fractional calculus.

  18. Spatial differentiation of China's summer tourist destinations based on climatic suitability using the Universal Thermal Climate Index

    Science.gov (United States)

    Yang, Jun; Zhang, Zhenchao; Li, Xueming; Xi, Jianchao; Feng, Zhangxian

    2017-11-01

    As a result of global warming and the gradual exacerbation of the urban heat island effect, vacationing in the summer to escape the heat has become a compelling tourism demand. This study examines the spatial differentiation of China's summer tourist destinations based on meteorological observations and tourism resources data from 1960 to 2014. The Universal Thermal Climate Index and analytic hierarchy process model were used to analyze climatic suitability. The findings are as follows. First, the spatial distribution of China's summer tourism resources exhibits a double-peak characteristic, with concentrations in the mid- and high-latitude and high-altitude regions. Second, the most influential destinations in China based on the composite index were Guiyang, Qingdao, Harbin, and Dalian. These findings can helpful for people who are planning their summer vacations, as well as tourism managers who benefit from such increases in the number of tourists.

  19. A Simple Differential Mode EMI Suppressor for the LLCL-Filter-Based Single-Phase Grid-Tied Transformerless Inverter

    DEFF Research Database (Denmark)

    Ji, Junhao; Wu, Weimin; He, Yuanbin

    2015-01-01

    The single-phase power converter topologies evolving of photovoltaic applications are still including passive filters, like the LCLor LLCL-filter. Compared with the LCL-filter, the total inductance of the LLCL-filter can be reduced a lot. However, due to the resonant inductor in series...... with the bypass capacitor, the differential mode (DM) electromagnetic interference (EMI) noise attenuation of an LLCL-filter-based grid-tied inverter declines. Conventionally, a capacitor was inserted in parallel with the LC resonant circuit branch of the LLCL-filter to suppress the DM EMI noise. In order...... to achieve a small value of capacitor as well as to minimize the additional reactive power, a novel simple DM EMI suppressor for the LLCL-filter-based system is proposed. The characters of two kinds of DM EMI suppressor are analyzed and compared in detail. Simulations and experiments on a 0.5-kW 110-V/50-Hz...

  20. Potential biological process of X-linked inhibitor of apoptosis protein in renal cell carcinoma based upon differential protein expression analysis.

    Science.gov (United States)

    Chen, Chao; Zhao, Si Cong; Yang, Wen Zheng; Chen, Zong Ping; Yan, Yong

    2018-01-01

    The X-linked inhibitor of apoptosis protein (XIAP) is the best characterized member of the IAP family and is a potent inhibitor of the caspase/apoptosis pathway. It has also been revealed that XIAP has additional biological functions that rely on its direct inhibition of apoptosis. In the present study, stably transfected Caki-1 cells with XIAP-knockdown were generated, and an isobaric tag for relative and absolute quantitation-based proteomics approach was employed to investigate the regulatory mechanism of XIAP in renal cell carcinoma (RCC). The results demonstrate that the sensitivity of the RCC cell line to apoptotic stimulation increased markedly with XIAP-knockdown. A number of differentially expressed proteins were detected between the original Caki-1 cell line and the XIAP-knockdown Caki-1 cell line; 87 at 0 h (prior to etoposide treatment), 178 at 0.5 h and 169 at 3 h, while no differentially expressed proteins were detected (ratio >1.5 or <0.5; P<0.05) at 12 h after etoposide treatment. Through analysis of the differentially expressed proteins, it was revealed that XIAP may participate in the tumor protein p53 pathway, the Wnt signaling pathway, glucose metabolism, endoplasmic reticulum stress, cytoskeletal regulation and DNA repair. These results indicate that XIAP may have a number of biological functions and may provide an insight into the biomedical significance of XIAP overexpression in RCC.

  1. Volume-based quantification using dual-energy computed tomography in the differentiation of thymic epithelial tumours: an initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Suyon; Hur, Jin; Im, Dong Jin; Suh, Young Joo; Hong, Yoo Jin; Lee, Hye-Jeong; Kim, Young Jin; Choi, Byoung Wook [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Seoul (Korea, Republic of); Han, Kyunghwa [Yonsei University College of Medicine, Yonsei Biomedical Research Institute, Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Seoul (Korea, Republic of); Kim, Dae Joon; Lee, Chang Young [Yonsei University College of Medicine, Department of Thoracic and Cardiovascular Surgery, Seoul (Korea, Republic of); Shin, Ha Young [Yonsei University College of Medicine, Department of Neurology, Seoul (Korea, Republic of)

    2017-05-15

    To investigate the diagnostic value of dual-energy computed tomography (DECT) in differentiating between low- and high-risk thymomas and thymic carcinomas. Our institutional review board approved this study, and patients provided informed consent. We prospectively enrolled 37 patients (20 males, mean age: 55.6 years) with thymic epithelial tumour. All patients underwent DECT. For quantitative analysis, two reviewers measured the following tumour parameters: CT attenuation value in contrast Hounsfield units (CHU), iodine-related HU and iodine concentration (mg/ml). Pathological results confirmed the final diagnosis. Of the 37 thymic tumours, 23 (62.2 %) were low-risk thymomas, five (13.5 %) were high-risk thymomas and nine (24.3 %) were thymic carcinomas. According to quantitative analysis, iodine-related HU and iodine concentration were significantly different among low-risk thymomas, high-risk thymomas and thymic carcinomas (median: 29.78 HU vs. 14.55 HU vs. 19.95 HU, p = 0.001 and 1.92 mg/ml vs. 0.99 mg/ml vs. 1.18 mg/ml, p < 0.001, respectively). DECT using a quantitative analytical method based on iodine concentration measurement can be used to differentiate among thymic epithelial tumours using single-phase scanning. (orig.)

  2. Differentiation vs. common targets in the climate change debate

    International Nuclear Information System (INIS)

    Dillon, J.

    1997-01-01

    A question of whether to impose common greenhouse gas emission targets and timetables on all nations was discussed. An examination of how different targets for different countries, based on national circumstances, might be implemented was presented, including a list of some of the factors that countries have put forward as criteria for differentiation. The advantages and disadvantages of a differentiated system of targets were described. It was argued that since the economic structures and the makeup of industries in any particular country are determining factors in the country's ability to reduce greenhouse gas emissions, not taking them into account is a certain invitation to failure. Developing countries, in particular, would benefit from a differentiated system of targets

  3. Differential pleiotropy and HOX functional organization.

    Science.gov (United States)

    Sivanantharajah, Lovesha; Percival-Smith, Anthony

    2015-02-01

    Key studies led to the idea that transcription factors are composed of defined modular protein motifs or domains, each with separable, unique function. During evolution, the recombination of these modular domains could give rise to transcription factors with new properties, as has been shown using recombinant molecules. This archetypic, modular view of transcription factor organization is based on the analyses of a few transcription factors such as GAL4, which may represent extreme exemplars rather than an archetype or the norm. Recent work with a set of Homeotic selector (HOX) proteins has revealed differential pleiotropy: the observation that highly-conserved HOX protein motifs and domains make small, additive, tissue specific contributions to HOX activity. Many of these differentially pleiotropic HOX motifs may represent plastic sequence elements called short linear motifs (SLiMs). The coupling of differential pleiotropy with SLiMs, suggests that protein sequence changes in HOX transcription factors may have had a greater impact on morphological diversity during evolution than previously believed. Furthermore, differential pleiotropy may be the genetic consequence of an ensemble nature of HOX transcription factor allostery, where HOX proteins exist as an ensemble of states with the capacity to integrate an extensive array of developmental information. Given a new structural model for HOX functional domain organization, the properties of the archetypic TF may require reassessment. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Trait anxiety and attenuated negative affect differentiation: a vulnerability factor to consider?

    Science.gov (United States)

    Matt, Lindsey M; Fresco, David M; Coifman, Karin G

    2016-11-01

    Describing emotional experiences using distinct terms, or affect differentiation, has been associated with emotion regulation and adaptive behavior under stress. There is little data, however, examining the association between differentiation and dispositional factors underlying psychopathology. The current study examines the association between differentiation and trait anxiety (TA) given prior evidence of cognitive biases in TA relevant to higher order processing of emotional experiences. We examined cross-sectionally, via lab-based repeated assessment, the association between differentiation of negative and positive experiences and TA. Two hundred twenty-two adults completed an emotion reactivity task including repeated assessments of affect. We hypothesized that individuals higher in trait anxiety (HTA) would have greater difficulty differentiating their experiences. HTA individuals exhibited lower levels of negative affect (NA) differentiation even when controlling for depression. Although negative emotion intensity was consistently associated with lower differentiation, this did not account for the influence of HTA on differentiation. These data suggest that HTA individuals have greater difficulty differentiating negative emotions, regardless of negative emotion intensity and depression. As HTA is common to many emotional disorders; this evidence suggests that poor differentiation may also be an important transdiagnostic consideration in models of risk and of affective disease.

  5. Natural Product Vibsanin A Induces Differentiation of Myeloid Leukemia Cells through PKC Activation.

    Science.gov (United States)

    Yu, Zu-Yin; Xiao, He; Wang, Li-Mei; Shen, Xing; Jing, Yu; Wang, Lin; Sun, Wen-Feng; Zhang, Yan-Feng; Cui, Yu; Shan, Ya-Jun; Zhou, Wen-Bing; Xing, Shuang; Xiong, Guo-Lin; Liu, Xiao-Lan; Dong, Bo; Feng, Jian-Nan; Wang, Li-Sheng; Luo, Qing-Liang; Zhao, Qin-Shi; Cong, Yu-Wen

    2016-05-01

    All-trans retinoic acid (ATRA)-based cell differentiation therapy has been successful in treating acute promyelocytic leukemia, a unique subtype of acute myeloid leukemia (AML). However, other subtypes of AML display resistance to ATRA-based treatment. In this study, we screened natural, plant-derived vibsane-type diterpenoids for their ability to induce differentiation of myeloid leukemia cells, discovering that vibsanin A potently induced differentiation of AML cell lines and primary blasts. The differentiation-inducing activity of vibsanin A was mediated through direct interaction with and activation of protein kinase C (PKC). Consistent with these findings, pharmacological blockade of PKC activity suppressed vibsanin A-induced differentiation. Mechanistically, vibsanin A-mediated activation of PKC led to induction of the ERK pathway and decreased c-Myc expression. In mouse xenograft models of AML, vibsanin A administration prolonged host survival and inhibited PKC-mediated inflammatory responses correlated with promotion of skin tumors in mice. Collectively, our results offer a preclinical proof of concept for vibsanin A as a myeloid differentiation-inducing compound, with potential application as an antileukemic agent. Cancer Res; 76(9); 2698-709. ©2016 AACR. ©2016 American Association for Cancer Research.

  6. The role of valence focus and appraisal overlap in emotion differentiation.

    Science.gov (United States)

    Erbas, Yasemin; Ceulemans, Eva; Koval, Peter; Kuppens, Peter

    2015-06-01

    Emotion differentiation refers to the level of specificity with which people distinguish between their emotional states and is considered to play an important role for psychological well-being. Yet, not much is known about what characterizes people high or low in emotion differentiation and what underlies these differences. In 2 studies involving experience sampling (Studies 1-2) and lab based (Study 2) methods, we investigated how emotion differentiation is related to individual differences in valence focus and the overlap in appraisal patterns between emotions. In line with expectations, results showed that high levels of both positive and negative emotion differentiation are related to lower levels of valence focus and lower levels of appraisal overlap between emotions. These findings suggest that individuals who are low in emotion differentiation mainly emphasize the valence aspect of emotions while individuals who are high in emotion differentiation make stronger distinctions between emotions in terms of their underlying appraisal profiles. (c) 2015 APA, all rights reserved).

  7. The development of a differential game related to terrorism: Min-Max differential game

    Directory of Open Access Journals (Sweden)

    Abd El-Monem A. Megahed

    2017-07-01

    Full Text Available In this work, we study a differential game related to terrorism: Min-Max differential game taking into account the governmental activities such as the education quality, increasing the chances of labor, social justice, religious awareness and security arrangements. A Min-Max differential game between government and terrorist organizations is considered in this study. To obtain the optimal strategy of solving this problem, we study the analytic form of a Min-Max differential game and the governmental activities. Furthermore, a saddle point of a Min-Max differential game is studied.

  8. Modulating Function-Based Method for Parameter and Source Estimation of Partial Differential Equations

    KAUST Repository

    Asiri, Sharefa M.

    2017-01-01

    Partial Differential Equations (PDEs) are commonly used to model complex systems that arise for example in biology, engineering, chemistry, and elsewhere. The parameters (or coefficients) and the source of PDE models are often unknown

  9. Differential-interference-contrast digital in-line holography microscopy based on a single-optical-element.

    Science.gov (United States)

    Zhang, Yuchao; Xie, Changqing

    2015-11-01

    Both digital in-line holography (DIH) and zone plate-based microscopy have received considerable interest as powerful imaging tools. However, the former suffers from a twin-image noise problem. The latter suffers from low efficiency and difficulty in fabrication. Here, we present an effective and efficient phase-contrast imaging approach, named differential-interference-contrast digital in-line holography (DIC-DIH), by using a single optical element to split the incident light into a plane wave and a converging spherical wave and generate a two-dimensional (2D) DIC effect simultaneously. Specifically, to improve image contrast, we present a new single optical element, termed 2D DIC compound photon sieves, by combining two overlaid binary gratings and a compound photon sieve through two logical XOR operations. The proof-of-concept experiments demonstrate that the proposed technique can eliminate the twin-image noise problem and improve image contrast with high efficiency. Additionally, we present an example of the phase-contrast imaging nonuniform thick photoresist development process.

  10. Integrator complex plays an essential role in adipose differentiation

    International Nuclear Information System (INIS)

    Otani, Yuichiro; Nakatsu, Yusuke; Sakoda, Hideyuki; Fukushima, Toshiaki; Fujishiro, Midori; Kushiyama, Akifumi; Okubo, Hirofumi; Tsuchiya, Yoshihiro; Ohno, Haruya; Takahashi, Shin-Ichiro; Nishimura, Fusanori; Kamata, Hideaki; Katagiri, Hideki; Asano, Tomoichiro

    2013-01-01

    Highlights: •IntS6 and IntS11 are subunits of the Integrator complex. •Expression levels of IntS6 and IntS11 were very low in 3T3-L1 fibroblast. •IntS6 and IntS11 were upregulated during adipose differentiation. •Suppression of IntS6 or IntS11 expression inhibited adipose differentiation. -- Abstract: The dynamic process of adipose differentiation involves stepwise expressions of transcription factors and proteins specific to the mature fat cell phenotype. In this study, it was revealed that expression levels of IntS6 and IntS11, subunits of the Integrator complex, were increased in 3T3-L1 cells in the period when the cells reached confluence and differentiated into adipocytes, while being reduced to basal levels after the completion of differentiation. Suppression of IntS6 or IntS11 expression using siRNAs in 3T3-L1 preadipocytes markedly inhibited differentiation into mature adipocytes, based on morphological findings as well as mRNA analysis of adipocyte-specific genes such as Glut4, perilipin and Fabp4. Although Pparγ2 protein expression was suppressed in IntS6 or IntS11-siRNA treated cells, adenoviral forced expression of Pparγ2 failed to restore the capacity for differentiation into mature adipocytes. Taken together, these findings demonstrate that increased expression of Integrator complex subunits is an indispensable event in adipose differentiation. Although further study is necessary to elucidate the underlying mechanism, the processing of U1, U2 small nuclear RNAs may be involved in cell differentiation steps

  11. Vector Differential Calculus

    OpenAIRE

    HITZER, Eckhard MS

    2002-01-01

    This paper treats the fundamentals of the vector differential calculus part of universal geometric calculus. Geometric calculus simplifies and unifies the structure and notation of mathematics for all of science and engineering, and for technological applications. In order to make the treatment self-contained, I first compile all important geometric algebra relationships,which are necesssary for vector differential calculus. Then differentiation by vectors is introduced and a host of major ve...

  12. Reduced differential transform method for partial differential equations within local fractional derivative operators

    Directory of Open Access Journals (Sweden)

    Hossein Jafari

    2016-04-01

    Full Text Available The non-differentiable solution of the linear and non-linear partial differential equations on Cantor sets is implemented in this article. The reduced differential transform method is considered in the local fractional operator sense. The four illustrative examples are given to show the efficiency and accuracy features of the presented technique to solve local fractional partial differential equations.

  13. Precise chronology of differentiation of developing human primary dentition.

    Science.gov (United States)

    Hu, Xuefeng; Xu, Shan; Lin, Chensheng; Zhang, Lishan; Chen, YiPing; Zhang, Yanding

    2014-02-01

    While correlation of developmental stage with embryonic age of the human primary dentition has been well documented, the available information regarding the differentiation timing of the primary teeth was largely based on the observation of initial mineralization and varies significantly. In this study, we aimed to document precise differentiation timing of the developing human primary dentition. We systematically examined the expression of odontogenic differentiation markers along with the formation of mineralized tissue in each developing maxillary and mandibular teeth from human embryos with well-defined embryonic age. We show that, despite that all primary teeth initiate development at the same time, odontogenic differentiation begins in the maxillary incisors at the 15th week and in the mandibular incisors at the 16th week of gestation, followed by the canine, the first primary premolar, and the second primary premolar at a week interval sequentially. Despite that the mandibular primary incisors erupt earlier than the maxillary incisors, this distal to proximal sequential differentiation of the human primary dentition coincides in general with the sequence of tooth eruption. Our results provide an accurate chronology of odontogenic differentiation of the developing human primary dentition, which could be used as reference for future studies of human tooth development.

  14. Concept for a Differential Lock and Traction Control Model in Automobiles

    Science.gov (United States)

    Shukul, A. K.; Hansra, S. K.

    2014-01-01

    The automobile is a complex integration of electronics and mechanical components. One of the major components is the differential which is limited due to its shortcomings. The paper proposes a concept of a cost effective differential lock and traction for passenger cars to sports utility vehicles alike, employing a parallel braking mechanism coming into action based on the relative speeds of the wheels driven by the differential. The paper highlights the employment of minimum number of components unlike the already existing systems. The system was designed numerically for the traction control and differential lock for the world's cheapest car. The paper manages to come up with all the system parameters and component costing making it a cost effective system.

  15. First principles design of divacancy defected graphene nanoribbon based rectifying and negative differential resistance device

    Energy Technology Data Exchange (ETDEWEB)

    Chakrabarty, Soubhik; Wasey, A. H. M. Abdul; Das, G. P., E-mail: msgpd@iacs.res.in, E-mail: ranjit.t@res.srmuniv.ac.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India); Thapa, Ranjit, E-mail: msgpd@iacs.res.in, E-mail: ranjit.t@res.srmuniv.ac.in [SRM Research Institute, SRM University, Kattankulathur - 603203, Tamil Nadu (India)

    2015-08-15

    We have studied using density functional theory and non-equilibrium Green’s function based approach, the electronic structures of 555-777 divacancy (DV) defected armchair edged graphene nanoribbons (AGNR) as well as the transport properties of AGNR based two-terminal devices constructed with one defected electrode and one N doped electrode. Introduction of 555-777 DV defect into AGNR results in shifting of the π and π∗ bands towards the higher energy value indicating a downward shift of the Fermi level. Formation of a potential barrier, analogous to that of conventional p-n junction, has been observed across the junction of defected and N-doped AGNR. The two terminal devices show diode like property with high rectifying efficiency for a wide range of bias voltages. The devices also show robust negative differential resistance with very high peak-to-valley ratio. Shift of the electrode energy states and modification of the transmission function with applied bias have been analyzed, in order to gain an insight into the nonlinear and asymmetric behavior of the current-voltage characteristics. Variation of the transport properties on the width of the ribbons has also been discussed.

  16. First principles design of divacancy defected graphene nanoribbon based rectifying and negative differential resistance device

    Directory of Open Access Journals (Sweden)

    Soubhik Chakrabarty

    2015-08-01

    Full Text Available We have studied using density functional theory and non-equilibrium Green’s function based approach, the electronic structures of 555-777 divacancy (DV defected armchair edged graphene nanoribbons (AGNR as well as the transport properties of AGNR based two-terminal devices constructed with one defected electrode and one N doped electrode. Introduction of 555-777 DV defect into AGNR results in shifting of the π and π∗ bands towards the higher energy value indicating a downward shift of the Fermi level. Formation of a potential barrier, analogous to that of conventional p-n junction, has been observed across the junction of defected and N-doped AGNR. The two terminal devices show diode like property with high rectifying efficiency for a wide range of bias voltages. The devices also show robust negative differential resistance with very high peak-to-valley ratio. Shift of the electrode energy states and modification of the transmission function with applied bias have been analyzed, in order to gain an insight into the nonlinear and asymmetric behavior of the current-voltage characteristics. Variation of the transport properties on the width of the ribbons has also been discussed.

  17. Comparison of differential pressure model based on flow regime for gas/liquid two-phase flow

    International Nuclear Information System (INIS)

    Dong, F; Zhang, F S; Li, W; Tan, C

    2009-01-01

    Gas/liquid two-phase flow in horizontal pipe is very common in many industry processes, because of the complexity and variability, the real-time parameter measurement of two-phase flow, such as the measurement of flow regime and flow rate, becomes a difficult issue in the field of engineering and science. The flow regime recognition plays a fundamental role in gas/liquid two-phase flow measurement, other parameters of two-phase flow can be measured more easily and correctly based on the correct flow regime recognition result. A multi-sensor system is introduced to make the flow regime recognition and the mass flow rate measurement. The fusion system is consisted of temperature sensor, pressure sensor, cross-section information system and v-cone flow meter. After the flow regime recognition by cross-section information system, comparison of four typical differential pressure (DP) models is discussed based on the DP signal of v-cone flow meter. Eventually, an optimum DP model has been chosen for each flow regime. The experiment result of mass flow rate measurement shows it is efficient to classify the DP models by flow regime.

  18. High-order tracking differentiator based adaptive neural control of a flexible air-breathing hypersonic vehicle subject to actuators constraints.

    Science.gov (United States)

    Bu, Xiangwei; Wu, Xiaoyan; Tian, Mingyan; Huang, Jiaqi; Zhang, Rui; Ma, Zhen

    2015-09-01

    In this paper, an adaptive neural controller is exploited for a constrained flexible air-breathing hypersonic vehicle (FAHV) based on high-order tracking differentiator (HTD). By utilizing functional decomposition methodology, the dynamic model is reasonably decomposed into the respective velocity subsystem and altitude subsystem. For the velocity subsystem, a dynamic inversion based neural controller is constructed. By introducing the HTD to adaptively estimate the newly defined states generated in the process of model transformation, a novel neural based altitude controller that is quite simpler than the ones derived from back-stepping is addressed based on the normal output-feedback form instead of the strict-feedback formulation. Based on minimal-learning parameter scheme, only two neural networks with two adaptive parameters are needed for neural approximation. Especially, a novel auxiliary system is explored to deal with the problem of control inputs constraints. Finally, simulation results are presented to test the effectiveness of the proposed control strategy in the presence of system uncertainties and actuators constraints. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Differentiation of drug and non-drug Cannabis using a single nucleotide polymorphism (SNP) assay.

    Science.gov (United States)

    Rotherham, D; Harbison, S A

    2011-04-15

    Cannabis sativa is both an illegal drug and a legitimate crop. The differentiation of illegal drug Cannabis from non-drug forms of Cannabis is relevant in the context of the growth of fibre and seed oil varieties of Cannabis for commercial purposes. This differentiation is currently determined based on the levels of tetrahydrocannabinol (THC) in adult plants. DNA based methods have the potential to assay Cannabis material unsuitable for analysis using conventional means including seeds, pollen and severely degraded material. The purpose of this research was to develop a single nucleotide polymorphism (SNP) assay for the differentiation of "drug" and "non-drug"Cannabis plants. An assay was developed based on four polymorphisms within a 399 bp fragment of the tetrahydrocannabinolic acid (THCA) synthase gene, utilising the snapshot multiplex kit. This SNP assay was tested on 94 Cannabis plants, which included 10 blind samples, and was able to differentiate between "drug" and "non-drug"Cannabis in all cases, while also differentiating between Cannabis and other species. Non-drug plants were found to be homozygous at the four sites assayed while drug Cannabis plants were either homozygous or heterozygous. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  20. Solving Bi-Objective Optimal Power Flow using Hybrid method of Biogeography-Based Optimization and Differential Evolution Algorithm: A case study of the Algerian Electrical Network

    Directory of Open Access Journals (Sweden)

    Ouafa Herbadji

    2016-03-01

    Full Text Available This paper proposes a new hybrid metaheuristique algorithm based on the hybridization of Biogeography-based optimization with the Differential Evolution for solving the optimal power flow problem with emission control. The biogeography-based optimization (BBO algorithm is strongly influenced by equilibrium theory of island biogeography, mainly through two steps: Migration and Mutation. Differential Evolution (DE is one of the best Evolutionary Algorithms for global optimization. The hybridization of these two methods is used to overcome traps of local optimal solutions and problems of time consumption. The objective of this paper is to minimize the total fuel cost of generation, total emission, total real power loss and also maintain an acceptable system performance in terms of limits on generator real power, bus voltages and power flow of transmission lines. In the present work, BBO/DE has been applied to solve the optimal power flow problems on IEEE 30-bus test system and the Algerian electrical network 114 bus. The results obtained from this method show better performances compared with DE, BBO and other well known metaheuristique and evolutionary optimization methods.

  1. Human Long Noncoding RNA Regulation of Stem Cell Potency and Differentiation

    Directory of Open Access Journals (Sweden)

    Seahyoung Lee

    2017-01-01

    Full Text Available Because of their capability of differentiation into lineage-specific cells, stem cells are an attractive therapeutic modality in regenerative medicine. To develop an effective stem cell-based therapeutic strategy with predictable results, deeper understanding of the underlying molecular mechanisms of stem cell differentiation and/or pluripotency maintenance is required. Thus, reviewing the key factors involved in the transcriptional and epigenetic regulation of stem cell differentiation and maintenance is important. Accumulating data indicate that long noncoding RNAs (lncRNAs mediate numerous biological processes, including stem cell differentiation and maintenance. Here, we review recent findings on the human lncRNA regulation of stem cell potency and differentiation. Although the clinical implication of these lncRNAs is only beginning to be elucidated, it is anticipated that lncRNAs will become important therapeutic targets in the near future.

  2. [Observation of curative effect of herpes zoster treated with acupuncture based on syndrome differentiation combined with pricking and cupping].

    Science.gov (United States)

    Pan, Hua

    2011-10-01

    To compare the differences of curative effects of herpes zoster treated with acupuncture based on syndrome differentiation combined with pricking and cupping and simple pricking and cupping. Eighty-six cases were randomly divided into an observation group (43 cases) and a control group (43 cases). In observation group, acupoints selection based on syndrome differentiation i.e. Quchi (LI 11), Zusanli (ST 36), Sanyinjiao (SP 6), etc. were selected and pricking and cupping at affected parts were applied, and the cases were classified into damp heat in liver and gallbladder, damp retention and spleen deficiency, and qi deficiency and blood stasis. In control group, all the cases were simplely treated with pricking and cupping at affected parts. The treatment was given once a day, and seven days were made one session. The curative effect was evaluated after 2 courses, and the follow-up was carried on after 1 month. The cured and markedly effective rate was 93.0% (40/43) in observation group, superior to that of 67.4% (29/43) in control group (P 0.05). The cured and markedly effective rate of damp retention and spleen deficiency: 93.8% (15/16) in observation group, superior to that of 60.0% (9/15) in control group (P cupping therapy is high pertinent and effective, the postherpetic neuralgia can be reduced significantly and the curative effect is superior to that of simple pricking and cupping.

  3. A new differential equations-based model for nonlinear history-dependent magnetic behaviour

    International Nuclear Information System (INIS)

    Aktaa, J.; Weth, A. von der

    2000-01-01

    The paper presents a new kind of numerical model describing nonlinear magnetic behaviour. The model is formulated as a set of differential equations taking into account history dependence phenomena like the magnetisation hysteresis as well as saturation effects. The capability of the model is demonstrated carrying out comparisons between measurements and calculations

  4. Derivation of a macroscale formulation for a class of nonlinear partial differential equations

    International Nuclear Information System (INIS)

    Pantelis, G.

    1995-05-01

    A macroscale formulation is constructed from a system of partial differential equations which govern the microscale dependent variables. The construction is based upon the requirement that the solutions of the macroscale partial differential equations satisfy, in some approximate sense, the system of partial differential equations associated with the microscale. These results are restricted to the class of nonlinear partial differential equations which can be expressed as polynomials of the dependent variables and their partial derivatives up to second order. A linear approximation of transformations of second order contact manifolds is employed. 6 refs

  5. Waveform relaxation methods for implicit differential equations

    NARCIS (Netherlands)

    P.J. van der Houwen; W.A. van der Veen

    1996-01-01

    textabstractWe apply a Runge-Kutta-based waveform relaxation method to initial-value problems for implicit differential equations. In the implementation of such methods, a sequence of nonlinear systems has to be solved iteratively in each step of the integration process. The size of these systems

  6. Continuous multistep methods for volterra integro-differential ...

    African Journals Online (AJOL)

    A new class of numerical methods for Volterra integro-differential equations of the second order is developed. The methods are based on interpolation and collocation of the shifted Legendre polynomial as basis function with Trapezoidal quadrature rules. The convergence analysis revealed that the methods are consistent ...

  7. Particle Swarm Optimization Based on Local Attractors of Ordinary Differential Equation System

    Directory of Open Access Journals (Sweden)

    Wenyu Yang

    2014-01-01

    Full Text Available Particle swarm optimization (PSO is inspired by sociological behavior. In this paper, we interpret PSO as a finite difference scheme for solving a system of stochastic ordinary differential equations (SODE. In this framework, the position points of the swarm converge to an equilibrium point of the SODE and the local attractors, which are easily defined by the present position points, also converge to the global attractor. Inspired by this observation, we propose a class of modified PSO iteration methods (MPSO based on local attractors of the SODE. The idea of MPSO is to choose the next update state near the present local attractor, rather than the present position point as in the original PSO, according to a given probability density function. In particular, the quantum-behaved particle swarm optimization method turns out to be a special case of MPSO by taking a special probability density function. The MPSO methods with six different probability density functions are tested on a few benchmark problems. These MPSO methods behave differently for different problems. Thus, our framework not only gives an interpretation for the ordinary PSO but also, more importantly, provides a warehouse of PSO-like methods to choose from for solving different practical problems.

  8. Platinum-Based Drugs Differentially Affect the Ultrastructure of Breast Cancer Cell Types

    Directory of Open Access Journals (Sweden)

    Shadia Al-Bahlani

    2017-01-01

    Full Text Available Breast cancer (BC is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM and transmission electron microscope (TEM. In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs’ deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment.

  9. A New Resources Provisioning Method Based on QoS Differentiation and VM Resizing in IaaS

    Directory of Open Access Journals (Sweden)

    Rongdong Hu

    2015-01-01

    Full Text Available In order to improve the host energy efficiency in IaaS, we proposed an adaptive host resource provisioning method, CoST, which is based on QoS differentiation and VM resizing. The control model can adaptively adjust control parameters according to real time application performance, in order to cope with changes in load. CoST takes advantage of the fact that different types of applications have different sensitivity degrees to performance and cost. It places two different types of VMs on the same host and dynamically adjusts their sizes based on the load forecasting and QoS feedback. It not only guarantees the performance defined in SLA, but also keeps the host running in energy-efficient state. Real Google cluster trace and host power data are used to evaluate the proposed method. Experimental results show that CoST can provide performance-sensitive application with a steady QoS and simultaneously speed up the overall processing of performance-tolerant application by 20~66%. The host energy efficiency is significantly improved by 7~23%.

  10. Synthetic niches for differentiation of human embryonic stem cells bypassing embryoid body formation.

    Science.gov (United States)

    Liu, Yarong; Fox, Victoria; Lei, Yuning; Hu, Biliang; Joo, Kye-Il; Wang, Pin

    2014-07-01

    The unique self-renewal and pluripotency features of human embryonic stem cells (hESCs) offer the potential for unlimited development of novel cell therapies. Currently, hESCs are cultured and differentiated using methods, such as monolayer culture and embryoid body (EB) formation. As such, achieving efficient differentiation into higher order structures remains a challenge, as well as maintaining cell viability during differentiation into homogeneous cell populations. Here, we describe the application of highly porous polymer scaffolds as synthetic stem cell niches. Bypassing the EB formation step, these scaffolds are capable of three-dimensional culture of undifferentiated hESCs and subsequent directed differentiation into three primary germ layers. H9 hESCs were successfully maintained and proliferated in biodegradable polymer scaffolds based on poly (lactic-co-glycolic acid) (PLGA). The results showed that cells within PLGA scaffolds retained characteristics of undifferentiated pluripotent stem cells. Moreover, the scaffolds allowed differentiation towards the lineage of interest by the addition of growth factors to the culture system. The in vivo transplantation study revealed that the scaffolds could provide a microenvironment that enabled hESCs to interact with their surroundings, thereby promoting cell differentiation. Therefore, this approach, which provides a unique culture/differentiation system for hESCs, will find its utility in various stem cell-based tissue-engineering applications. © 2013 Wiley Periodicals, Inc.

  11. Differential equations, mechanics, and computation

    CERN Document Server

    Palais, Richard S

    2009-01-01

    This book provides a conceptual introduction to the theory of ordinary differential equations, concentrating on the initial value problem for equations of evolution and with applications to the calculus of variations and classical mechanics, along with a discussion of chaos theory and ecological models. It has a unified and visual introduction to the theory of numerical methods and a novel approach to the analysis of errors and stability of various numerical solution algorithms based on carefully chosen model problems. While the book would be suitable as a textbook for an undergraduate or elementary graduate course in ordinary differential equations, the authors have designed the text also to be useful for motivated students wishing to learn the material on their own or desiring to supplement an ODE textbook being used in a course they are taking with a text offering a more conceptual approach to the subject.

  12. GWAS-based pathway analysis differentiates between fluid and crystallized intelligence.

    Science.gov (United States)

    Christoforou, A; Espeseth, T; Davies, G; Fernandes, C P D; Giddaluru, S; Mattheisen, M; Tenesa, A; Harris, S E; Liewald, D C; Payton, A; Ollier, W; Horan, M; Pendleton, N; Haggarty, P; Djurovic, S; Herms, S; Hoffman, P; Cichon, S; Starr, J M; Lundervold, A; Reinvang, I; Steen, V M; Deary, I J; Le Hellard, S

    2014-09-01

    Cognitive abilities vary among people. About 40-50% of this variability is due to general intelligence (g), which reflects the positive correlation among individuals' scores on diverse cognitive ability tests. g is positively correlated with many life outcomes, such as education, occupational status and health, motivating the investigation of its underlying biology. In psychometric research, a distinction is made between general fluid intelligence (gF) - the ability to reason in novel situations - and general crystallized intelligence (gC) - the ability to apply acquired knowledge. This distinction is supported by developmental and cognitive neuroscience studies. Classical epidemiological studies and recent genome-wide association studies (GWASs) have established that these cognitive traits have a large genetic component. However, no robust genetic associations have been published thus far due largely to the known polygenic nature of these traits and insufficient sample sizes. Here, using two GWAS datasets, in which the polygenicity of gF and gC traits was previously confirmed, a gene- and pathway-based approach was undertaken with the aim of characterizing and differentiating their genetic architecture. Pathway analysis, using genes selected on the basis of relaxed criteria, revealed notable differences between these two traits. gF appeared to be characterized by genes affecting the quantity and quality of neurons and therefore neuronal efficiency, whereas long-term depression (LTD) seemed to underlie gC. Thus, this study supports the gF-gC distinction at the genetic level and identifies functional annotations and pathways worthy of further investigation. © 2014 The Authors. Genes, Brain and Behavior published by International Behavioural and Neural Genetics Society and John Wiley & Sons Ltd.

  13. Microarray-based screening of differentially expressed genes in glucocorticoid-induced avascular necrosis

    Science.gov (United States)

    Huang, Gangyong; Wei, Yibing; Zhao, Guanglei; Xia, Jun; Wang, Siqun; Wu, Jianguo; Chen, Feiyan; Chen, Jie; Shi, Jingshen

    2017-01-01

    The underlying mechanisms of glucocorticoid (GC)-induced avascular necrosis of the femoral head (ANFH) have yet to be fully understood, in particular the mechanisms associated with the change of gene expression pattern. The present study aimed to identify key genes with a differential expression pattern in GC-induced ANFH. E-MEXP-2751 microarray data were downloaded from the ArrayExpress database. Differentially expressed genes (DEGs) were identified in 5 femoral head samples of steroid-induced ANFH rats compared with 5 placebo-treated rat samples. Gene Ontology (GO) and pathway enrichment analyses were performed upon these DEGs. A total 93 DEGs (46 upregulated and 47 downregulated genes) were identified in GC-induced ANFH samples. These DEGs were enriched in different GO terms and pathways, including chondrocyte differentiation and detection of chemical stimuli. The enrichment map revealed that skeletal system development was interconnected with several other GO terms by gene overlap. The literature mined network analysis revealed that 5 upregulated genes were associated with femoral necrosis, including parathyroid hormone receptor 1 (PTHR1), vitamin D (1,25-Dihydroxyvitamin D3) receptor (VDR), collagen, type II, α1, proprotein convertase subtilisin/kexin type 6 and zinc finger protein 354C (ZFP354C). In addition, ZFP354C and VDR were identified to transcription factors. Furthermore, PTHR1 was revealed to interact with VDR, and α-2-macroglobulin (A2M) interacted with fibronectin 1 (FN1) in the PPI network. PTHR1 may be involved in GC-induced ANFH via interacting with VDR. A2M may also be involved in the development of GC-induced ANFH through interacting with FN1. An improved understanding of the molecular mechanisms underlying GC-induced ANFH may provide novel targets for diagnostics and therapeutic treatment. PMID:28393228

  14. Microarray‑based screening of differentially expressed genes in glucocorticoid‑induced avascular necrosis.

    Science.gov (United States)

    Huang, Gangyong; Wei, Yibing; Zhao, Guanglei; Xia, Jun; Wang, Siqun; Wu, Jianguo; Chen, Feiyan; Chen, Jie; Shi, Jingshen

    2017-06-01

    The underlying mechanisms of glucocorticoid (GC)‑induced avascular necrosis of the femoral head (ANFH) have yet to be fully understood, in particular the mechanisms associated with the change of gene expression pattern. The present study aimed to identify key genes with a differential expression pattern in GC‑induced ANFH. E‑MEXP‑2751 microarray data were downloaded from the ArrayExpress database. Differentially expressed genes (DEGs) were identified in 5 femoral head samples of steroid‑induced ANFH rats compared with 5 placebo‑treated rat samples. Gene Ontology (GO) and pathway enrichment analyses were performed upon these DEGs. A total 93 DEGs (46 upregulated and 47 downregulated genes) were identified in GC‑induced ANFH samples. These DEGs were enriched in different GO terms and pathways, including chondrocyte differentiation and detection of chemical stimuli. The enrichment map revealed that skeletal system development was interconnected with several other GO terms by gene overlap. The literature mined network analysis revealed that 5 upregulated genes were associated with femoral necrosis, including parathyroid hormone receptor 1 (PTHR1), vitamin D (1,25‑Dihydroxyvitamin D3) receptor (VDR), collagen, type II, α1, proprotein convertase subtilisin/kexin type 6 and zinc finger protein 354C (ZFP354C). In addition, ZFP354C and VDR were identified to transcription factors. Furthermore, PTHR1 was revealed to interact with VDR, and α‑2‑macroglobulin (A2M) interacted with fibronectin 1 (FN1) in the PPI network. PTHR1 may be involved in GC‑induced ANFH via interacting with VDR. A2M may also be involved in the development of GC‑induced ANFH through interacting with FN1. An improved understanding of the molecular mechanisms underlying GC‑induced ANFH may provide novel targets for diagnostics and therapeutic treatment.

  15. Radiomics-based differentiation of lung disease models generated by polluted air based on X-ray computed tomography data

    International Nuclear Information System (INIS)

    Szigeti, Krisztián; Szabó, Tibor; Korom, Csaba; Czibak, Ilona; Horváth, Ildikó; Veres, Dániel S.; Gyöngyi, Zoltán; Karlinger, Kinga; Bergmann, Ralf; Pócsik, Márta; Budán, Ferenc; Máthé, Domokos

    2016-01-01

    Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann–Whitney post hoc (MWph) tests were used. Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas. The online version of this article (doi:10.1186/s12880-016-0118-z) contains supplementary material, which is available to authorized users

  16. A Receiver for Differential Space-Time -Shifted BPSK Modulation Based on Scalar-MSDD and the EM Algorithm

    Directory of Open Access Journals (Sweden)

    Kim Jae H

    2005-01-01

    Full Text Available In this paper, we consider the issue of blind detection of Alamouti-type differential space-time (ST modulation in static Rayleigh fading channels. We focus our attention on a -shifted BPSK constellation, introducing a novel transformation to the received signal such that this binary ST modulation, which has a second-order transmit diversity, is equivalent to QPSK modulation with second-order receive diversity. This equivalent representation allows us to apply a low-complexity detection technique specifically designed for receive diversity, namely, scalar multiple-symbol differential detection (MSDD. To further increase receiver performance, we apply an iterative expectation-maximization (EM algorithm which performs joint channel estimation and sequence detection. This algorithm uses minimum mean square estimation to obtain channel estimates and the maximum-likelihood principle to detect the transmitted sequence, followed by differential decoding. With receiver complexity proportional to the observation window length, our receiver can achieve the performance of a coherent maximal ratio combining receiver (with differential decoding in as few as a single EM receiver iteration, provided that the window size of the initial MSDD is sufficiently long. To further demonstrate that the MSDD is a vital part of this receiver setup, we show that an initial ST conventional differential detector would lead to strange convergence behavior in the EM algorithm.

  17. Chromatin plasticity as a differentiation index during muscle differentiation of C2C12 myoblasts

    International Nuclear Information System (INIS)

    Watanabe, Tomonobu M.; Higuchi, Sayaka; Kawauchi, Keiko; Tsukasaki, Yoshikazu; Ichimura, Taro; Fujita, Hideaki

    2012-01-01

    Highlights: ► Change in the epigenetic landscape during myogenesis was optically investigated. ► Mobility of nuclear proteins was used to state the epigenetic status of the cell. ► Mobility of nuclear proteins decreased as myogenesis progressed in C2C12. ► Differentiation state diagram was developed using parameters obtained. -- Abstract: Skeletal muscle undergoes complicated differentiation steps that include cell-cycle arrest, cell fusion, and maturation, which are controlled through sequential expression of transcription factors. During muscle differentiation, remodeling of the epigenetic landscape is also known to take place on a large scale, determining cell fate. In an attempt to determine the extent of epigenetic remodeling during muscle differentiation, we characterized the plasticity of the chromatin structure using C2C12 myoblasts. Differentiation of C2C12 cells was induced by lowering the serum concentration after they had reached full confluence, resulting in the formation of multi-nucleated myotubes. Upon induction of differentiation, the nucleus size decreased whereas the aspect ratio increased, indicating the presence of force on the nucleus during differentiation. Movement of the nucleus was also suppressed when differentiation was induced, indicating that the plasticity of chromatin changed upon differentiation. To evaluate the histone dynamics during differentiation, FRAP experiment was performed, which showed an increase in the immobile fraction of histone proteins when differentiation was induced. To further evaluate the change in the histone dynamics during differentiation, FCS was performed, which showed a decrease in histone mobility on differentiation. We here show that the plasticity of chromatin decreases upon differentiation, which takes place in a stepwise manner, and that it can be used as an index for the differentiation stage during myogenesis using the state diagram developed with the parameters obtained in this study.

  18. Differential mobility in plasm

    International Nuclear Information System (INIS)

    Jewur, S.S.

    1983-01-01

    Theoretical considerations about the technique based on differential plasma mobility are made for the analysis of trace amounts of chemical products. The mechanisms for the formation of reagent-ion, reaction between ion and molecule, separation of ions and molecules and production of plasmogram, are explained. Despite being a very modern technique and the equipment has not yet been put in the market, it is already confirmed that the structural sensitivity of the fluctuation time in DPM is greater than the retention time in chromatographic techniques. (CLB) [pt

  19. A hanging drop culture method to study terminal erythroid differentiation.

    Science.gov (United States)

    Gutiérrez, Laura; Lindeboom, Fokke; Ferreira, Rita; Drissen, Roy; Grosveld, Frank; Whyatt, David; Philipsen, Sjaak

    2005-10-01

    To design a culture method allowing the quantitative and qualitative analysis of terminal erythroid differentiation. Primary erythroid progenitors derived either from mouse tissues or from human umbilical cord blood were differentiated using hanging drop cultures and compared to methylcellulose cultures. Cultured cells were analyzed by FACS to assess differentiation. We describe a practical culture method by adapting the previously described hanging drop culture system to conditions allowing terminal differentiation of primary erythroid progenitors. Using minimal volumes of media and small numbers of cells, we obtained quantitative terminal erythroid differentiation within two days of culture in the case of murine cells and 4 days in the case of human cells. The established methods for ex vivo culture of primary erythroid progenitors, such as methylcellulose-based burst-forming unit-erythroid (BFU-E) and colony-forming unit-erythroid (CFU-E) assays, allow the detection of committed erythroid progenitors but are of limited value to study terminal erythroid differentiation. We show that the application of hanging drop cultures is a practical alternative that, in combination with clonogenic assays, enables a comprehensive assessment of the behavior of primary erythroid cells ex vivo in the context of genetic and drug-induced perturbations.

  20. Differential gene expression profiling of human adipose stem cells differentiating into smooth muscle-like cells by TGFβ1/BMP4

    Energy Technology Data Exchange (ETDEWEB)

    Elçin, Ayşe Eser; Parmaksiz, Mahmut; Dogan, Arin; Seker, Sukran; Durkut, Serap; Dalva, Klara; Elçin, Yaşar Murat, E-mail: elcinmurat@gmail.com

    2017-03-15

    Regenerative repair of the vascular system is challenging from the perspectives of translational medicine and tissue engineering. There are fundamental hurdles in front of creating bioartificial arteries, which involve recaputilation of the three-layered structure under laboratory settings. Obtaining and maintaining smooth muscle characteristics is an important limitation, as the transdifferentiated cells fail to display mature phenotype. This study aims to shed light on the smooth muscle differentiation of human adipose stem cells (hASCs). To this end, we first acquired hASCs from lipoaspirate samples. Upon characterization, the cells were induced to differentiate into smooth muscle (SM)-like cells using a variety of inducer combinations. Among all, TGFβ1/BMP4 combination had the highest differentiation efficiency, based on immunohistochemical analyses. hSM-like cell samples were compared to hASCs and to the positive control, human coronary artery-smooth muscle cells (hCA-SMCs) through gene transcription profiling. Microarray findings revealed the activation of gene groups that function in smooth muscle differentiation, signaling pathways, extracellular modeling and cell proliferation. Our results underline the effectiveness of the growth factors and suggest some potential variables for detecting the SM-like cell characteristics. Evidence in transcriptome level was used to evaluate the TGFβ1/BMP4 combination as a previously unexplored effector for the smooth muscle differentiation of adipose stem cells. - Highlights: • Human adipose stem cells (hASCs) were isolated, characterized and cultured. • Growth factor combinations were evaluated for their effectiveness in differentiation using IHC. • hASCs were differentiated into smooth muscle (SM)-like cells using TGF-β1 and BMP4 combination. • Microarray analysis was performed for hASCs, SM-like cells and coronary artery-SMCs. • Microarray data was used to perform hierarchical clustering and interpretation

  1. Differential GNSS and Vision-Based Tracking to Improve Navigation Performance in Cooperative Multi-UAV Systems

    Directory of Open Access Journals (Sweden)

    Amedeo Rodi Vetrella

    2016-12-01

    Full Text Available Autonomous navigation of micro-UAVs is typically based on the integration of low cost Global Navigation Satellite System (GNSS receivers and Micro-Electro-Mechanical Systems (MEMS-based inertial and magnetic sensors to stabilize and control the flight. The resulting navigation performance in terms of position and attitude accuracy may not suffice for other mission needs, such as the ones relevant to fine sensor pointing. In this framework, this paper presents a cooperative UAV navigation algorithm that allows a chief vehicle, equipped with inertial and magnetic sensors, a Global Positioning System (GPS receiver, and a vision system, to improve its navigation performance (in real time or in the post processing phase exploiting formation flying deputy vehicles equipped with GPS receivers. The focus is set on outdoor environments and the key concept is to exploit differential GPS among vehicles and vision-based tracking (DGPS/Vision to build a virtual additional navigation sensor whose information is then integrated in a sensor fusion algorithm based on an Extended Kalman Filter. The developed concept and processing architecture are described, with a focus on DGPS/Vision attitude determination algorithm. Performance assessment is carried out on the basis of both numerical simulations and flight tests. In the latter ones, navigation estimates derived from the DGPS/Vision approach are compared with those provided by the onboard autopilot system of a customized quadrotor. The analysis shows the potential of the developed approach, mainly deriving from the possibility to exploit magnetic- and inertial-independent accurate attitude information.

  2. Differential equations for dummies

    CERN Document Server

    Holzner, Steven

    2008-01-01

    The fun and easy way to understand and solve complex equations Many of the fundamental laws of physics, chemistry, biology, and economics can be formulated as differential equations. This plain-English guide explores the many applications of this mathematical tool and shows how differential equations can help us understand the world around us. Differential Equations For Dummies is the perfect companion for a college differential equations course and is an ideal supplemental resource for other calculus classes as well as science and engineering courses. It offers step-by-step techniques, practical tips, numerous exercises, and clear, concise examples to help readers improve their differential equation-solving skills and boost their test scores.

  3. An algebraic iterative reconstruction technique for differential X-ray phase-contrast computed tomography.

    Science.gov (United States)

    Fu, Jian; Schleede, Simone; Tan, Renbo; Chen, Liyuan; Bech, Martin; Achterhold, Klaus; Gifford, Martin; Loewen, Rod; Ruth, Ronald; Pfeiffer, Franz

    2013-09-01

    Iterative reconstruction has a wide spectrum of proven advantages in the field of conventional X-ray absorption-based computed tomography (CT). In this paper, we report on an algebraic iterative reconstruction technique for grating-based differential phase-contrast CT (DPC-CT). Due to the differential nature of DPC-CT projections, a differential operator and a smoothing operator are added to the iterative reconstruction, compared to the one commonly used for absorption-based CT data. This work comprises a numerical study of the algorithm and its experimental verification using a dataset measured at a two-grating interferometer setup. Since the algorithm is easy to implement and allows for the extension to various regularization possibilities, we expect a significant impact of the method for improving future medical and industrial DPC-CT applications. Copyright © 2012. Published by Elsevier GmbH.

  4. SU-D-BRA-04: Computerized Framework for Marker-Less Localization of Anatomical Feature Points in Range Images Based On Differential Geometry Features for Image-Guided Radiation Therapy

    International Nuclear Information System (INIS)

    Soufi, M; Arimura, H; Toyofuku, F; Nakamura, K; Hirose, T; Umezu, Y; Shioyama, Y

    2016-01-01

    Purpose: To propose a computerized framework for localization of anatomical feature points on the patient surface in infrared-ray based range images by using differential geometry (curvature) features. Methods: The general concept was to reconstruct the patient surface by using a mathematical modeling technique for the computation of differential geometry features that characterize the local shapes of the patient surfaces. A region of interest (ROI) was firstly extracted based on a template matching technique applied on amplitude (grayscale) images. The extracted ROI was preprocessed for reducing temporal and spatial noises by using Kalman and bilateral filters, respectively. Next, a smooth patient surface was reconstructed by using a non-uniform rational basis spline (NURBS) model. Finally, differential geometry features, i.e. the shape index and curvedness features were computed for localizing the anatomical feature points. The proposed framework was trained for optimizing shape index and curvedness thresholds and tested on range images of an anthropomorphic head phantom. The range images were acquired by an infrared ray-based time-of-flight (TOF) camera. The localization accuracy was evaluated by measuring the mean of minimum Euclidean distances (MMED) between reference (ground truth) points and the feature points localized by the proposed framework. The evaluation was performed for points localized on convex regions (e.g. apex of nose) and concave regions (e.g. nasofacial sulcus). Results: The proposed framework has localized anatomical feature points on convex and concave anatomical landmarks with MMEDs of 1.91±0.50 mm and 3.70±0.92 mm, respectively. A statistically significant difference was obtained between the feature points on the convex and concave regions (P<0.001). Conclusion: Our study has shown the feasibility of differential geometry features for localization of anatomical feature points on the patient surface in range images. The proposed

  5. SU-D-BRA-04: Computerized Framework for Marker-Less Localization of Anatomical Feature Points in Range Images Based On Differential Geometry Features for Image-Guided Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Soufi, M; Arimura, H; Toyofuku, F [Kyushu University, Fukuoka, Fukuoka (Japan); Nakamura, K [Hamamatsu University School of Medicine, Hamamatsu, Shizuoka (Japan); Hirose, T; Umezu, Y [Kyushu University Hospital, Fukuoka, Fukuoka (Japan); Shioyama, Y [Saga Heavy Ion Medical Accelerator in Tosu, Tosu, Saga (Japan)

    2016-06-15

    Purpose: To propose a computerized framework for localization of anatomical feature points on the patient surface in infrared-ray based range images by using differential geometry (curvature) features. Methods: The general concept was to reconstruct the patient surface by using a mathematical modeling technique for the computation of differential geometry features that characterize the local shapes of the patient surfaces. A region of interest (ROI) was firstly extracted based on a template matching technique applied on amplitude (grayscale) images. The extracted ROI was preprocessed for reducing temporal and spatial noises by using Kalman and bilateral filters, respectively. Next, a smooth patient surface was reconstructed by using a non-uniform rational basis spline (NURBS) model. Finally, differential geometry features, i.e. the shape index and curvedness features were computed for localizing the anatomical feature points. The proposed framework was trained for optimizing shape index and curvedness thresholds and tested on range images of an anthropomorphic head phantom. The range images were acquired by an infrared ray-based time-of-flight (TOF) camera. The localization accuracy was evaluated by measuring the mean of minimum Euclidean distances (MMED) between reference (ground truth) points and the feature points localized by the proposed framework. The evaluation was performed for points localized on convex regions (e.g. apex of nose) and concave regions (e.g. nasofacial sulcus). Results: The proposed framework has localized anatomical feature points on convex and concave anatomical landmarks with MMEDs of 1.91±0.50 mm and 3.70±0.92 mm, respectively. A statistically significant difference was obtained between the feature points on the convex and concave regions (P<0.001). Conclusion: Our study has shown the feasibility of differential geometry features for localization of anatomical feature points on the patient surface in range images. The proposed

  6. Algorithmic Verification of Linearizability for Ordinary Differential Equations

    KAUST Repository

    Lyakhov, Dmitry A.; Gerdt, Vladimir P.; Michels, Dominik L.

    2017-01-01

    one by a point transformation of the dependent and independent variables. The first algorithm is based on a construction of the Lie point symmetry algebra and on the computation of its derived algebra. The second algorithm exploits the differential

  7. A Model-Based Joint Identification of Differentially Expressed Genes and Phenotype-Associated Genes

    Science.gov (United States)

    Seo, Minseok; Shin, Su-kyung; Kwon, Eun-Young; Kim, Sung-Eun; Bae, Yun-Jung; Lee, Seungyeoun; Sung, Mi-Kyung; Choi, Myung-Sook; Park, Taesung

    2016-01-01

    Over the last decade, many analytical methods and tools have been developed for microarray data. The detection of differentially expressed genes (DEGs) among different treatment groups is often a primary purpose of microarray data analysis. In addition, association studies investigating the relationship between genes and a phenotype of interest such as survival time are also popular in microarray data analysis. Phenotype association analysis provides a list of phenotype-associated genes (PAGs). However, it is sometimes necessary to identify genes that are both DEGs and PAGs. We consider the joint identification of DEGs and PAGs in microarray data analyses. The first approach we used was a naïve approach that detects DEGs and PAGs separately and then identifies the genes in an intersection of the list of PAGs and DEGs. The second approach we considered was a hierarchical approach that detects DEGs first and then chooses PAGs from among the DEGs or vice versa. In this study, we propose a new model-based approach for the joint identification of DEGs and PAGs. Unlike the previous two-step approaches, the proposed method identifies genes simultaneously that are DEGs and PAGs. This method uses standard regression models but adopts different null hypothesis from ordinary regression models, which allows us to perform joint identification in one-step. The proposed model-based methods were evaluated using experimental data and simulation studies. The proposed methods were used to analyze a microarray experiment in which the main interest lies in detecting genes that are both DEGs and PAGs, where DEGs are identified between two diet groups and PAGs are associated with four phenotypes reflecting the expression of leptin, adiponectin, insulin-like growth factor 1, and insulin. Model-based approaches provided a larger number of genes, which are both DEGs and PAGs, than other methods. Simulation studies showed that they have more power than other methods. Through analysis of

  8. A Model-Based Joint Identification of Differentially Expressed Genes and Phenotype-Associated Genes.

    Directory of Open Access Journals (Sweden)

    Samuel Sunghwan Cho

    Full Text Available Over the last decade, many analytical methods and tools have been developed for microarray data. The detection of differentially expressed genes (DEGs among different treatment groups is often a primary purpose of microarray data analysis. In addition, association studies investigating the relationship between genes and a phenotype of interest such as survival time are also popular in microarray data analysis. Phenotype association analysis provides a list of phenotype-associated genes (PAGs. However, it is sometimes necessary to identify genes that are both DEGs and PAGs. We consider the joint identification of DEGs and PAGs in microarray data analyses. The first approach we used was a naïve approach that detects DEGs and PAGs separately and then identifies the genes in an intersection of the list of PAGs and DEGs. The second approach we considered was a hierarchical approach that detects DEGs first and then chooses PAGs from among the DEGs or vice versa. In this study, we propose a new model-based approach for the joint identification of DEGs and PAGs. Unlike the previous two-step approaches, the proposed method identifies genes simultaneously that are DEGs and PAGs. This method uses standard regression models but adopts different null hypothesis from ordinary regression models, which allows us to perform joint identification in one-step. The proposed model-based methods were evaluated using experimental data and simulation studies. The proposed methods were used to analyze a microarray experiment in which the main interest lies in detecting genes that are both DEGs and PAGs, where DEGs are identified between two diet groups and PAGs are associated with four phenotypes reflecting the expression of leptin, adiponectin, insulin-like growth factor 1, and insulin. Model-based approaches provided a larger number of genes, which are both DEGs and PAGs, than other methods. Simulation studies showed that they have more power than other methods

  9. Differentiation of breast cancer stem cells by knockdown of CD44: promising differentiation therapy

    Directory of Open Access Journals (Sweden)

    Pham Phuc V

    2011-12-01

    Full Text Available Abstract Background Breast cancer stem cells (BCSCs are the source of breast tumors. Compared with other cancer cells, cancer stem cells show high resistance to both chemotherapy and radiotherapy. Targeting of BCSCs is thus a potentially promising and effective strategy for breast cancer treatment. Differentiation therapy represents one type of cancer stem-cell-targeting therapy, aimed at attacking the stemness of cancer stem cells, thus reducing their chemo- and radioresistance. In a previous study, we showed that down-regulation of CD44 sensitized BCSCs to the anti-tumor agent doxorubicin. This study aimed to determine if CD44 knockdown caused BCSCs to differentiate into breast cancer non-stem cells (non-BCSCs. Methods We isolated a breast cancer cell population (CD44+CD24- cells from primary cultures of malignant breast tumors. These cells were sorted into four sub-populations based on their expression of CD44 and CD24 surface markers. CD44 knockdown in the BCSC population was achieved using small hairpin RNA lentivirus particles. The differentiated status of CD44 knock-down BCSCs was evaluated on the basis of changes in CD44+CD24- phenotype, tumorigenesis in NOD/SCID mice, and gene expression in relation to renewal status, metastasis, and cell cycle in comparison with BCSCs and non-BCSCs. Results Knockdown of CD44 caused BCSCs to differentiate into non-BCSCs with lower tumorigenic potential, and altered the cell cycle and expression profiles of some stem cell-related genes, making them more similar to those seen in non-BCSCs. Conclusions Knockdown of CD44 is an effective strategy for attacking the stemness of BCSCs, resulting in a loss of stemness and an increase in susceptibility to chemotherapy or radiation. The results of this study highlight a potential new strategy for breast cancer treatment through the targeting of BCSCs.

  10. Differential Detector for Measuring Radiation Fields

    International Nuclear Information System (INIS)

    Broide, A.; Marcus, E.; Brandys, I.; Schwartz, A.; Wengrowicz, U.; Levinson, S.; Seif, R.; Sattinger, D.; Kadmon, Y.; Tal, N.

    2004-01-01

    In case of a nuclear accident, it is essential to determine the source of radioactive contamination in order to analyze the risk to the environment and to the population. The radiation source may be a radioactive plume on the air or an area on the ground contaminated with radionuclides. Most commercial radiation detectors measure only the radiation field intensity but are unable to differentiate between the radiation sources. Consequently, this limitation causes a real problem in analyzing the potential risk to the near-by environment, since there is no data concerning the contamination ratios in the air and on the ground and this prevents us from taking the required steps to deal with the radiation event. This work presents a GM-tube-based Differential Detector, which enables to determine the source of contamination

  11. Solving Linear Differential Equations

    NARCIS (Netherlands)

    Nguyen, K.A.; Put, M. van der

    2010-01-01

    The theme of this paper is to 'solve' an absolutely irreducible differential module explicitly in terms of modules of lower dimension and finite extensions of the differential field K. Representations of semi-simple Lie algebras and differential Galo is theory are the main tools. The results extend

  12. Multi-spectral endogenous fluorescence imaging for bacterial differentiation

    Science.gov (United States)

    Chernomyrdin, Nikita V.; Babayants, Margarita V.; Korotkov, Oleg V.; Kudrin, Konstantin G.; Rimskaya, Elena N.; Shikunova, Irina A.; Kurlov, Vladimir N.; Cherkasova, Olga P.; Komandin, Gennady A.; Reshetov, Igor V.; Zaytsev, Kirill I.

    2017-07-01

    In this paper, the multi-spectral endogenous fluorescence imaging was implemented for bacterial differentiation. The fluorescence imaging was performed using a digital camera equipped with a set of visual bandpass filters. Narrowband 365 nm ultraviolet radiation passed through a beam homogenizer was used to excite the sample fluorescence. In order to increase a signal-to-noise ratio and suppress a non-fluorescence background in images, the intensity of the UV excitation was modulated using a mechanical chopper. The principal components were introduced for differentiating the samples of bacteria based on the multi-spectral endogenous fluorescence images.

  13. Fundamentals of differential beamforming

    CERN Document Server

    Benesty, Jacob; Pan, Chao

    2016-01-01

    This book provides a systematic study of the fundamental theory and methods of beamforming with differential microphone arrays (DMAs), or differential beamforming in short. It begins with a brief overview of differential beamforming and some popularly used DMA beampatterns such as the dipole, cardioid, hypercardioid, and supercardioid, before providing essential background knowledge on orthogonal functions and orthogonal polynomials, which form the basis of differential beamforming. From a physical perspective, a DMA of a given order is defined as an array that measures the differential acoustic pressure field of that order; such an array has a beampattern in the form of a polynomial whose degree is equal to the DMA order. Therefore, the fundamental and core problem of differential beamforming boils down to the design of beampatterns with orthogonal polynomials. But certain constraints also have to be considered so that the resulting beamformer does not seriously amplify the sensors’ self noise and the mism...

  14. Differential Effects of Sodium Butyrate and Lithium Chloride on Rhesus Monkey Trophoblast Differentiation.

    Directory of Open Access Journals (Sweden)

    Priyadarsini Kumar

    Full Text Available Trophoblast differentiation during early placental development is critical for successful pregnancy and aberrant differentiation causes preeclampsia and early pregnancy loss. During the first trimester, cytotrophoblasts are exposed to low oxygen tension (equivalent to~2%-3% O2 and differentiation proceeds along an extravillous pathway (giving rise to invasive extravillous cytotrophoblasts and a villous pathway (giving rise to multinucleated syncytiotrophoblast. Interstitial extravillous cytotrophoblasts invade the decidua, while endovascular extravillous cytotrophoblasts are involved in re-modelling uterine spiral arteries. We tested the idea that sodium butyrate (an epigenetic modulator induces trophoblast differentiation in early gestation rhesus monkey trophoblasts through activation of the Wnt/β-catenin pathway. The results show that syncytiotrophoblast formation was increased by butyrate, accompanied by nuclear accumulation of β-catenin, and increased expression of EnvV2 and galectin-1 (two factors thought to be involved in trophoblast fusion. Surprisingly, the expression of GCM1 and syncytin-2 was not affected by sodium butyrate. When trophoblasts were incubated with lithium chloride, a GSK3 inhibitor that mimics Wnt activation, nuclear accumulation of β-catenin also occurred but differentiation into syncytiotrophoblast was not observed. Instead the cells differentiated to mononucleated spindle-shaped cells and showed molecular and behavioral characteristics of endovascular trophoblasts. Another highly specific inhibitor of GSK3, CHIR99021, failed to induce endovascular trophoblast characteristics. These observations suggest that activation of the Wnt/β-catenin pathway correlates with both trophoblast differentiation pathways, but that additional factors determine specific cell fate decisions. Other experiments suggested that the differential effects of sodium butyrate and lithium chloride might be explained by their effects on TNF

  15. Simulation of logical traffic isolation using differentiated services

    CSIR Research Space (South Africa)

    Dlamini, I

    2009-06-01

    Full Text Available This paper extends work on a forensic model for traffic isolation based on Differentiated Services (DiffServ) and measures its performance by using a simulation. The simulated model has four basic components: traffic generators, the DiffServ network...

  16. Stability test for a parabolic partial differential equation

    NARCIS (Netherlands)

    Vajta, Miklos

    2001-01-01

    The paper describes a stability test applied to coupled parabolic partial differential equations. The PDE's describe the temperature distribution of composite structures with linear inner heat sources. The distributed transfer functions are developed based on the transmission matrix of each layer.

  17. Differential scanning calorimetric study of HTPB based composite propellants in presence of nano ferric oxide

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Prajakta R.; Krishnamurthy, V.N.; Joshi, Satyawati S. [Department of Chemistry, University of Pune, Pune 411007 (India)

    2006-12-15

    A comparative study of the thermal decomposition of ammonium perchlorate (AP)/hydroxy terminated polybutadiene (HTPB) based composite propellants has been carried out in presence and absence of nano iron oxide at different heating rates in a dynamic nitrogen atmosphere using differential scanning calorimetry. The pronounced effect was a lowering of the high temperature decomposition by 49 C. A higher heat release up to 40% was observed in presence of nano ferric oxide (3.5 nm). The kinetic parameters were evaluated using the Kissinger method. The increase of the rate constant in the catalyzed propellant confirmed the enhancement of the catalytic activity of ammonium perchlorate. The scanning electron micrographs of nano Fe{sub 2}O{sub 3} incorporated in HTPB revealed a well-separated characteristic necklace-like structure of {alpha}-Fe{sub 2}O{sub 3} particles at high magnification. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  18. Differential algebras without differentials: An easy C++ implementation

    International Nuclear Information System (INIS)

    Michelotti, L.

    1989-03-01

    Automated differentiation can be motivated and explained rather plainly without any reference to infinitesimals or differentials whatsoever. We shall describe one possible approach in this paper. The method which we shall use will suggest its own implementation. However, FORTRAN is not the most natural language in which to carry it out. In the second section we shall describe an almost trivial implementation using C++. (Indeed, one of the motivations for writing this paper is to persuade militant FORTRAN extremists to invest the four or five days necessary to learn this powerful and easy language.) Take heed, however, that what we describe below is only a stripped-down implementation, written in three days, of differential algebra's most essential features; it is not as robust as and does not contain the battery of tools available in Berz's DA package, the product of a significant amount of work. 10 refs

  19. Differential algebras without differentials: An easy C++ implementation

    Energy Technology Data Exchange (ETDEWEB)

    Michelotti, L.

    1989-03-01

    Automated differentiation can be motivated and explained rather plainly without any reference to infinitesimals or differentials whatsoever. We shall describe one possible approach in this paper. The method which we shall use will suggest its own implementation. However, FORTRAN is not the most natural language in which to carry it out. In the second section we shall describe an almost trivial implementation using C++. (Indeed, one of the motivations for writing this paper is to persuade militant FORTRAN extremists to invest the four or five days necessary to learn this powerful and easy language.) Take heed, however, that what we describe below is only a stripped-down implementation, written in three days, of differential algebra's most essential features; it is not as robust as and does not contain the battery of tools available in Berz's DA package, the product of a significant amount of work. 10 refs.

  20. Introduction to differentiable manifolds

    CERN Document Server

    Auslander, Louis

    2009-01-01

    The first book to treat manifold theory at an introductory level, this text surveys basic concepts in the modern approach to differential geometry. The first six chapters define and illustrate differentiable manifolds, and the final four chapters investigate the roles of differential structures in a variety of situations.Starting with an introduction to differentiable manifolds and their tangent spaces, the text examines Euclidean spaces, their submanifolds, and abstract manifolds. Succeeding chapters explore the tangent bundle and vector fields and discuss their association with ordinary diff