Zero-truncated negative binomial - Erlang distribution

Science.gov (United States)

Bodhisuwan, Winai; Pudprommarat, Chookait; Bodhisuwan, Rujira; Saothayanun, Luckhana

2017-11-01

The zero-truncated negative binomial-Erlang distribution is introduced. It is developed from negative binomial-Erlang distribution. In this work, the probability mass function is derived and some properties are included. The parameters of the zero-truncated negative binomial-Erlang distribution are estimated by using the maximum likelihood estimation. Finally, the proposed distribution is applied to real data, the number of methamphetamine in the Bangkok, Thailand. Based on the results, it shows that the zero-truncated negative binomial-Erlang distribution provided a better fit than the zero-truncated Poisson, zero-truncated negative binomial, zero-truncated generalized negative-binomial and zero-truncated Poisson-Lindley distributions for this data.

Angular truncation errors in integrating nephelometry

International Nuclear Information System (INIS)

Moosmueller, Hans; Arnott, W. Patrick

2003-01-01

Ideal integrating nephelometers integrate light scattered by particles over all directions. However, real nephelometers truncate light scattered in near-forward and near-backward directions below a certain truncation angle (typically 7 deg. ). This results in truncation errors, with the forward truncation error becoming important for large particles. Truncation errors are commonly calculated using Mie theory, which offers little physical insight and no generalization to nonspherical particles. We show that large particle forward truncation errors can be calculated and understood using geometric optics and diffraction theory. For small truncation angles (i.e., <10 deg. ) as typical for modern nephelometers, diffraction theory by itself is sufficient. Forward truncation errors are, by nearly a factor of 2, larger for absorbing particles than for nonabsorbing particles because for large absorbing particles most of the scattered light is due to diffraction as transmission is suppressed. Nephelometers calibration procedures are also discussed as they influence the effective truncation error

No evidence that protein truncating variants in BRIP1 are associated with breast cancer risk: implications for gene panel testing

OpenAIRE

Easton, Douglas Frederick; Lesueur, Fabienne; Decker, Brennan; Michailidou, Kyriaki; Li, Jun; Allen, Jamie; Luccarini, Craig; Pooley, Karen Anne; Shah, Mitulkumar Nandlal; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; Ahmad, Jamil; Thompson, Ella R; Damiola, Francesca

2016-01-01

Background BRCA1 interacting protein C-terminal helicase 1 (BRIP1) is one of the Fanconi Anaemia Complementation (FANC) group family of DNA repair proteins. Biallelic mutations in BRIP1 are responsible for FANC group J, and previous studies have also suggested that rare protein truncating variants in BRIP1 are associated with an increased risk of breast cancer. These studies have led to inclusion of BRIP1 on targeted sequencing panels for breast cancer risk prediction. Metho...

Use of the truncated shifted Pareto distribution in assessing size distribution of oil and gas fields

Science.gov (United States)

Houghton, J.C.

1988-01-01

The truncated shifted Pareto (TSP) distribution, a variant of the two-parameter Pareto distribution, in which one parameter is added to shift the distribution right and left and the right-hand side is truncated, is used to model size distributions of oil and gas fields for resource assessment. Assumptions about limits to the left-hand and right-hand side reduce the number of parameters to two. The TSP distribution has advantages over the more customary lognormal distribution because it has a simple analytic expression, allowing exact computation of several statistics of interest, has a "J-shape," and has more flexibility in the thickness of the right-hand tail. Oil field sizes from the Minnelusa play in the Powder River Basin, Wyoming and Montana, are used as a case study. Probability plotting procedures allow easy visualization of the fit and help the assessment. ?? 1988 International Association for Mathematical Geology.

Truncated Groebner fans and lattice ideals

OpenAIRE

Lauritzen, Niels

2005-01-01

We outline a generalization of the Groebner fan of a homogeneous ideal with maximal cells parametrizing truncated Groebner bases. This "truncated" Groebner fan is usually much smaller than the full Groebner fan and offers the natural framework for conversion between truncated Groebner bases. The generic Groebner walk generalizes naturally to this setting by using the Buchberger algorithm with truncation on facets. We specialize to the setting of lattice ideals. Here facets along the generic w...

A Support Vector Machine Approach for Truncated Fingerprint Image Detection from Sweeping Fingerprint Sensors

Science.gov (United States)

Chen, Chi-Jim; Pai, Tun-Wen; Cheng, Mox

2015-01-01

A sweeping fingerprint sensor converts fingerprints on a row by row basis through image reconstruction techniques. However, a built fingerprint image might appear to be truncated and distorted when the finger was swept across a fingerprint sensor at a non-linear speed. If the truncated fingerprint images were enrolled as reference targets and collected by any automated fingerprint identification system (AFIS), successful prediction rates for fingerprint matching applications would be decreased significantly. In this paper, a novel and effective methodology with low time computational complexity was developed for detecting truncated fingerprints in a real time manner. Several filtering rules were implemented to validate existences of truncated fingerprints. In addition, a machine learning method of supported vector machine (SVM), based on the principle of structural risk minimization, was applied to reject pseudo truncated fingerprints containing similar characteristics of truncated ones. The experimental result has shown that an accuracy rate of 90.7% was achieved by successfully identifying truncated fingerprint images from testing images before AFIS enrollment procedures. The proposed effective and efficient methodology can be extensively applied to all existing fingerprint matching systems as a preliminary quality control prior to construction of fingerprint templates. PMID:25835186

A Support Vector Machine Approach for Truncated Fingerprint Image Detection from Sweeping Fingerprint Sensors

Directory of Open Access Journals (Sweden)

Chi-Jim Chen

2015-03-01

Full Text Available A sweeping fingerprint sensor converts fingerprints on a row by row basis through image reconstruction techniques. However, a built fingerprint image might appear to be truncated and distorted when the finger was swept across a fingerprint sensor at a non-linear speed. If the truncated fingerprint images were enrolled as reference targets and collected by any automated fingerprint identification system (AFIS, successful prediction rates for fingerprint matching applications would be decreased significantly. In this paper, a novel and effective methodology with low time computational complexity was developed for detecting truncated fingerprints in a real time manner. Several filtering rules were implemented to validate existences of truncated fingerprints. In addition, a machine learning method of supported vector machine (SVM, based on the principle of structural risk minimization, was applied to reject pseudo truncated fingerprints containing similar characteristics of truncated ones. The experimental result has shown that an accuracy rate of 90.7% was achieved by successfully identifying truncated fingerprint images from testing images before AFIS enrollment procedures. The proposed effective and efficient methodology can be extensively applied to all existing fingerprint matching systems as a preliminary quality control prior to construction of fingerprint templates.

Statistical estimation for truncated exponential families

CERN Document Server

Akahira, Masafumi

2017-01-01

This book presents new findings on nonregular statistical estimation. Unlike other books on this topic, its major emphasis is on helping readers understand the meaning and implications of both regularity and irregularity through a certain family of distributions. In particular, it focuses on a truncated exponential family of distributions with a natural parameter and truncation parameter as a typical nonregular family. This focus includes the (truncated) Pareto distribution, which is widely used in various fields such as finance, physics, hydrology, geology, astronomy, and other disciplines. The family is essential in that it links both regular and nonregular distributions, as it becomes a regular exponential family if the truncation parameter is known. The emphasis is on presenting new results on the maximum likelihood estimation of a natural parameter or truncation parameter if one of them is a nuisance parameter. In order to obtain more information on the truncation, the Bayesian approach is also considere...

NLO renormalization in the Hamiltonian truncation

Science.gov (United States)

Elias-Miró, Joan; Rychkov, Slava; Vitale, Lorenzo G.

2017-09-01

Hamiltonian truncation (also known as "truncated spectrum approach") is a numerical technique for solving strongly coupled quantum field theories, in which the full Hilbert space is truncated to a finite-dimensional low-energy subspace. The accuracy of the method is limited only by the available computational resources. The renormalization program improves the accuracy by carefully integrating out the high-energy states, instead of truncating them away. In this paper, we develop the most accurate ever variant of Hamiltonian Truncation, which implements renormalization at the cubic order in the interaction strength. The novel idea is to interpret the renormalization procedure as a result of integrating out exactly a certain class of high-energy "tail states." We demonstrate the power of the method with high-accuracy computations in the strongly coupled two-dimensional quartic scalar theory and benchmark it against other existing approaches. Our work will also be useful for the future goal of extending Hamiltonian truncation to higher spacetime dimensions.

ABO blood groups: A risk factor for left atrial and left atrial appendage thrombogenic milieu in patients with non-valvular atrial fibrillation.

Science.gov (United States)

Fu, Yuan; Li, Kuibao; Yang, Xinchun

2017-08-01

Previous studies have identified ABO blood groups as predictors of thromboembolic diseases. In patients with atrial fibrillation (AF), however, potential association between ABO blood groups and the risk of left atrial (LA) and/or left atrial appendage (LAA) thrombogenic milieu (TM) has not been established. This is a retrospective case-control study that included 125 consecutive patients with non-valvular atrial fibrillation (NVAF) plus TM, as evidenced by transesophageal echocardiography (TEE) during a period from1 January 2010 to 31 December 2016. The controls were selected randomly from 1072 NVAF without TM at a 1:2 ratio. Potential association between ABO blood groups and TM was analyzed using multivariate logistic regression analysis. The risk of TM was higher in patients with blood group A (33.6% vs. 20.2% in non-A blood groups, P=0.005). After adjusting for age, sex, oral anticoagulant use, AF type and duration, and relevant functional measures (e.g., NT-pro BNP level, left atrium diameter, and left ventricular ejection fraction), blood group A remained associated with an increased risk of TM (OR=2.99, 95% CI 1.4-6.388, P=0.005). Blood group A is an independent risk factor for TM in NVAF patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stability of Slopes Reinforced with Truncated Piles

Directory of Open Access Journals (Sweden)

Shu-Wei Sun

2016-01-01

Full Text Available Piles are extensively used as a means of slope stabilization. A novel engineering technique of truncated piles that are unlike traditional piles is introduced in this paper. A simplified numerical method is proposed to analyze the stability of slopes stabilized with truncated piles based on the shear strength reduction method. The influential factors, which include pile diameter, pile spacing, depth of truncation, and existence of a weak layer, are systematically investigated from a practical point of view. The results show that an optimum ratio exists between the depth of truncation and the pile length above a slip surface, below which truncating behavior has no influence on the piled slope stability. This optimum ratio is bigger for slopes stabilized with more flexible piles and piles with larger spacing. Besides, truncated piles are more suitable for slopes with a thin weak layer than homogenous slopes. In practical engineering, the piles could be truncated reasonably while ensuring the reinforcement effect. The truncated part of piles can be filled with the surrounding soil and compacted to reduce costs by using fewer materials.

Adaptation of the delta-m and δ-fit truncation methods to vector radiative transfer: Effect of truncation on radiative transfer accuracy

International Nuclear Information System (INIS)

Sanghavi, Suniti; Stephens, Graeme

2015-01-01

In the presence of aerosol and/or clouds, the use of appropriate truncation methods becomes indispensable for accurate but cost-efficient radiative transfer computations. Truncation methods allow the reduction of the large number (usually several hundreds) of Fourier components associated with particulate scattering functions to a more manageable number, thereby making it possible to carry out radiative transfer computations with a modest number of streams. While several truncation methods have been discussed for scalar radiative transfer, few rigorous studies have been made of truncation methods for the vector case. Here, we formally derive the vector form of Wiscombe's delta-m truncation method. Two main sources of error associated with delta-m truncation are identified as the delta-separation error (DSE) and the phase-truncation error (PTE). The view angles most affected by truncation error occur in the vicinity of the direction of exact backscatter. This view geometry occurs commonly in satellite based remote sensing applications, and is hence of considerable importance. In order to deal with these errors, we adapt the δ-fit approach of Hu et al. (2000) [17] to vector radiative transfer. The resulting δBGE-fit is compared with the vectorized delta-m method. For truncation at l=25 of an original phase matrix consisting of over 300 Fourier components, the use of the δBGE-fit minimizes the error due to truncation at these view angles, while practically eliminating error at other angles. We also show how truncation errors have a distorting effect on hyperspectral absorption line shapes. The choice of the δBGE-fit method over delta-m truncation minimizes errors in absorption line depths, thus affording greater accuracy for sensitive retrievals such as those of XCO 2 from OCO-2 or GOSAT measurements. - Highlights: • Derives vector form for delta-m truncation method. • Adapts δ-fit truncation approach to vector RTE as δBGE-fit. • Compares truncation

Computing correct truncated excited state wavefunctions

Science.gov (United States)

Bacalis, N. C.; Xiong, Z.; Zang, J.; Karaoulanis, D.

2016-12-01

We demonstrate that, if a wave function's truncated expansion is small, then the standard excited states computational method, of optimizing one "root" of a secular equation, may lead to an incorrect wave function - despite the correct energy according to the theorem of Hylleraas, Undheim and McDonald - whereas our proposed method [J. Comput. Meth. Sci. Eng. 8, 277 (2008)] (independent of orthogonality to lower lying approximants) leads to correct reliable small truncated wave functions. The demonstration is done in He excited states, using truncated series expansions in Hylleraas coordinates, as well as standard configuration-interaction truncated expansions.

Mixtures of truncated basis functions

DEFF Research Database (Denmark)

Langseth, Helge; Nielsen, Thomas Dyhre; Rumí, Rafael

2012-01-01

In this paper we propose a framework, called mixtures of truncated basis functions (MoTBFs), for representing general hybrid Bayesian networks. The proposed framework generalizes both the mixture of truncated exponentials (MTEs) framework and the mixture of polynomials (MoPs) framework. Similar t...

Applications of Fast Truncated Multiplication in Cryptography

Directory of Open Access Journals (Sweden)

Laszlo Hars

2006-12-01

Full Text Available Truncated multiplications compute truncated products, contiguous subsequences of the digits of integer products. For an n-digit multiplication algorithm of time complexity O(nα, with 1<α≤2, there is a truncated multiplication algorithm, which is constant times faster when computing a short enough truncated product. Applying these fast truncated multiplications, several cryptographic long integer arithmetic algorithms are improved, including integer reciprocals, divisions, Barrett and Montgomery multiplications, 2n-digit modular multiplication on hardware for n-digit half products. For example, Montgomery multiplication is performed in 2.6 Karatsuba multiplication time.

Properties of truncated multiplicity distributions

International Nuclear Information System (INIS)

Lupia, S.

1995-01-01

Truncation effects on multiplicity distributions are discussed. Observables sensitive to the tail, like factorial moments, factorial cumulants and their ratio, are shown to be strongly affected by truncation. A possible way to overcome this problem by looking at the head of the distribution is suggested. (author)

Properties of truncated multiplicity distributions

Energy Technology Data Exchange (ETDEWEB)

Lupia, S. [Turin Univ. (Italy). Dipt. di Fisica

1995-12-31

Truncation effects on multiplicity distributions are discussed. Observables sensitive to the tail, like factorial moments, factorial cumulants and their ratio, are shown to be strongly affected by truncation. A possible way to overcome this problem by looking at the head of the distribution is suggested. (author)

Analysis of truncation limit in probabilistic safety assessment

International Nuclear Information System (INIS)

Cepin, Marko

2005-01-01

A truncation limit defines the boundaries of what is considered in the probabilistic safety assessment and what is neglected. The truncation limit that is the focus here is the truncation limit on the size of the minimal cut set contribution at which to cut off. A new method was developed, which defines truncation limit in probabilistic safety assessment. The method specifies truncation limits with more stringency than presenting existing documents dealing with truncation criteria in probabilistic safety assessment do. The results of this paper indicate that the truncation limits for more complex probabilistic safety assessments, which consist of larger number of basic events, should be more severe than presently recommended in existing documents if more accuracy is desired. The truncation limits defined by the new method reduce the relative errors of importance measures and produce more accurate results for probabilistic safety assessment applications. The reduced relative errors of importance measures can prevent situations, where the acceptability of change of equipment under investigation according to RG 1.174 would be shifted from region, where changes can be accepted, to region, where changes cannot be accepted, if the results would be calculated with smaller truncation limit

Truncated Calogero-Sutherland models

Science.gov (United States)

Pittman, S. M.; Beau, M.; Olshanii, M.; del Campo, A.

2017-05-01

A one-dimensional quantum many-body system consisting of particles confined in a harmonic potential and subject to finite-range two-body and three-body inverse-square interactions is introduced. The range of the interactions is set by truncation beyond a number of neighbors and can be tuned to interpolate between the Calogero-Sutherland model and a system with nearest and next-nearest neighbors interactions discussed by Jain and Khare. The model also includes the Tonks-Girardeau gas describing impenetrable bosons as well as an extension with truncated interactions. While the ground state wave function takes a truncated Bijl-Jastrow form, collective modes of the system are found in terms of multivariable symmetric polynomials. We numerically compute the density profile, one-body reduced density matrix, and momentum distribution of the ground state as a function of the range r and the interaction strength.

Lamp with a truncated reflector cup

Science.gov (United States)

Li, Ming; Allen, Steven C.; Bazydola, Sarah; Ghiu, Camil-Daniel

2013-10-15

A lamp assembly, and method for making same. The lamp assembly includes first and second truncated reflector cups. The lamp assembly also includes at least one base plate disposed between the first and second truncated reflector cups, and a light engine disposed on a top surface of the at least one base plate. The light engine is configured to emit light to be reflected by one of the first and second truncated reflector cups.

Formal truncations of connected kernel equations

International Nuclear Information System (INIS)

Dixon, R.M.

1977-01-01

The Connected Kernel Equations (CKE) of Alt, Grassberger and Sandhas (AGS); Kouri, Levin and Tobocman (KLT); and Bencze, Redish and Sloan (BRS) are compared against reaction theory criteria after formal channel space and/or operator truncations have been introduced. The Channel Coupling Class concept is used to study the structure of these CKE's. The related wave function formalism of Sandhas, of L'Huillier, Redish and Tandy and of Kouri, Krueger and Levin are also presented. New N-body connected kernel equations which are generalizations of the Lovelace three-body equations are derived. A method for systematically constructing fewer body models from the N-body BRS and generalized Lovelace (GL) equations is developed. The formally truncated AGS, BRS, KLT and GL equations are analyzed by employing the criteria of reciprocity and two-cluster unitarity. Reciprocity considerations suggest that formal truncations of BRS, KLT and GL equations can lead to reciprocity-violating results. This study suggests that atomic problems should employ three-cluster connected truncations and that the two-cluster connected truncations should be a useful starting point for nuclear systems

Perspective on rainbow-ladder truncation

International Nuclear Information System (INIS)

Eichmann, G.; Alkofer, R.; Krassnigg, A.; Cloeet, I. C.; Roberts, C. D.

2008-01-01

Prima facie the systematic implementation of corrections to the rainbow-ladder truncation of QCD's Dyson-Schwinger equations will uniformly reduce in magnitude those calculated mass-dimensioned results for pseudoscalar and vector meson properties that are not tightly constrained by symmetries. The aim and interpretation of studies employing rainbow-ladder truncation are reconsidered in this light

Behavioral approach system sensitivity and risk taking interact to predict left-frontal EEG asymmetry.

Science.gov (United States)

Black, Chelsea L; Goldstein, Kim E; LaBelle, Denise R; Brown, Christopher W; Harmon-Jones, Eddie; Abramson, Lyn Y; Alloy, Lauren B

2014-09-01

The Behavioral Approach System (BAS) hypersensitivity theory of bipolar disorder (BD; Alloy & Abramson, 2010; Depue & Iacono, 1989) suggests that hyperreactivity in the BAS results in the extreme fluctuations of mood characteristic of BD. In addition to risk conferred by BAS hypersensitivity, cognitive and personality variables may play a role in determining risk. We evaluated relationships among BAS sensitivity, risk taking, and an electrophysiological correlate of approach motivation, relative left-frontal electroencephalography (EEG) asymmetry. BAS sensitivity moderated the relationship between risk taking and EEG asymmetry. More specifically, individuals who were high in BAS sensitivity showed left-frontal EEG asymmetry regardless of their level of risk-taking behavior. However, among individuals who were moderate in BAS sensitivity, risk taking was positively associated with asymmetry. These findings suggest that cognitive and personality correlates of bipolar risk may evidence unique contributions to a neural measure of trait-approach motivation. Clinical implications of these findings are discussed. Copyright © 2014. Published by Elsevier Ltd.

Truncation correction for oblique filtering lines

International Nuclear Information System (INIS)

Hoppe, Stefan; Hornegger, Joachim; Lauritsch, Guenter; Dennerlein, Frank; Noo, Frederic

2008-01-01

State-of-the-art filtered backprojection (FBP) algorithms often define the filtering operation to be performed along oblique filtering lines in the detector. A limited scan field of view leads to the truncation of those filtering lines, which causes artifacts in the final reconstructed volume. In contrast to the case where filtering is performed solely along the detector rows, no methods are available for the case of oblique filtering lines. In this work, the authors present two novel truncation correction methods which effectively handle data truncation in this case. Method 1 (basic approach) handles data truncation in two successive preprocessing steps by applying a hybrid data extrapolation method, which is a combination of a water cylinder extrapolation and a Gaussian extrapolation. It is independent of any specific reconstruction algorithm. Method 2 (kink approach) uses similar concepts for data extrapolation as the basic approach but needs to be integrated into the reconstruction algorithm. Experiments are presented from simulated data of the FORBILD head phantom, acquired along a partial-circle-plus-arc trajectory. The theoretically exact M-line algorithm is used for reconstruction. Although the discussion is focused on theoretically exact algorithms, the proposed truncation correction methods can be applied to any FBP algorithm that exposes oblique filtering lines.

A min cut-set-wise truncation procedure for importance measures computation in probabilistic safety assessment

Energy Technology Data Exchange (ETDEWEB)

Duflot, Nicolas [Universite de technologie de Troyes, Institut Charles Delaunay/LM2S, FRE CNRS 2848, 12, rue Marie Curie, BP2060, F-10010 Troyes cedex (France)], E-mail: nicolas.duflot@areva.com; Berenguer, Christophe [Universite de technologie de Troyes, Institut Charles Delaunay/LM2S, FRE CNRS 2848, 12, rue Marie Curie, BP2060, F-10010 Troyes cedex (France)], E-mail: christophe.berenguer@utt.fr; Dieulle, Laurence [Universite de technologie de Troyes, Institut Charles Delaunay/LM2S, FRE CNRS 2848, 12, rue Marie Curie, BP2060, F-10010 Troyes cedex (France)], E-mail: laurence.dieulle@utt.fr; Vasseur, Dominique [EPSNA Group (Nuclear PSA and Application), EDF Research and Development, 1, avenue du Gal de Gaulle, 92141 Clamart cedex (France)], E-mail: dominique.vasseur@edf.fr

2009-11-15

A truncation process aims to determine among the set of minimal cut-sets (MCS) produced by a probabilistic safety assessment (PSA) model which of them are significant. Several truncation processes have been proposed for the evaluation of the probability of core damage ensuring a fixed accuracy level. However, the evaluation of new risk indicators as importance measures requires to re-examine the truncation process in order to ensure that the produced estimates will be accurate enough. In this paper a new truncation process is developed permitting to estimate from a single set of MCS the importance measure of any basic event with the desired accuracy level. The main contribution of this new method is to propose an MCS-wise truncation criterion involving two thresholds: an absolute threshold in addition to a new relative threshold concerning the potential probability of the MCS of interest. The method has been tested on a complete level 1 PSA model of a 900 MWe NPP developed by 'Electricite de France' (EDF) and the results presented in this paper indicate that to reach the same accuracy level the proposed method produces a set of MCS whose size is significantly reduced.

A min cut-set-wise truncation procedure for importance measures computation in probabilistic safety assessment

International Nuclear Information System (INIS)

Duflot, Nicolas; Berenguer, Christophe; Dieulle, Laurence; Vasseur, Dominique

2009-01-01

A truncation process aims to determine among the set of minimal cut-sets (MCS) produced by a probabilistic safety assessment (PSA) model which of them are significant. Several truncation processes have been proposed for the evaluation of the probability of core damage ensuring a fixed accuracy level. However, the evaluation of new risk indicators as importance measures requires to re-examine the truncation process in order to ensure that the produced estimates will be accurate enough. In this paper a new truncation process is developed permitting to estimate from a single set of MCS the importance measure of any basic event with the desired accuracy level. The main contribution of this new method is to propose an MCS-wise truncation criterion involving two thresholds: an absolute threshold in addition to a new relative threshold concerning the potential probability of the MCS of interest. The method has been tested on a complete level 1 PSA model of a 900 MWe NPP developed by 'Electricite de France' (EDF) and the results presented in this paper indicate that to reach the same accuracy level the proposed method produces a set of MCS whose size is significantly reduced.

Complicated left-sided native valve endocarditis in adults: risk classification for mortality.

Science.gov (United States)

Hasbun, Rodrigo; Vikram, Holenarasipur R; Barakat, Lydia A; Buenconsejo, Joan; Quagliarello, Vincent J

2003-04-16

Complicated left-sided native valve endocarditis causes significant morbidity and mortality in adults. Lack of valid data regarding estimation of prognosis makes management of this condition difficult. To derive and externally validate a prognostic classification system for adults with complicated left-sided native valve endocarditis. Retrospective observational cohort study conducted from January 1990 to January 2000 at 7 Connecticut hospitals among 513 patients older than 16 years who experienced complicated left-sided native valve endocarditis and who were divided into derivation (n = 259) and validation (n = 254) cohorts. All-cause mortality at 6 months after baseline. In the derivation and validation cohorts, the 6-month mortality rates were 25% and 26%, respectively. Five baseline features were independently associated with 6-month mortality (comorbidity [P =.03], abnormal mental status [P =.02], moderate to severe congestive heart failure [P =.01], bacterial etiology other than viridans streptococci [Pclassification system. In the derivation cohort, patients were classified into 4 groups with increasing risk for 6-month mortality: 5%, 15%, 31%, and 59% (Pendocarditis can be accurately risk stratified using baseline features into 4 groups of prognostic severity. This prognostic classification system might be useful for facilitating management decisions.

Analysis of the upper-truncated Weibull distribution for wind speed

International Nuclear Information System (INIS)

Kantar, Yeliz Mert; Usta, Ilhan

2015-01-01

Highlights: • Upper-truncated Weibull distribution is proposed to model wind speed. • Upper-truncated Weibull distribution nests Weibull distribution as special case. • Maximum likelihood is the best method for upper-truncated Weibull distribution. • Fitting accuracy of upper-truncated Weibull is analyzed on wind speed data. - Abstract: Accurately modeling wind speed is critical in estimating the wind energy potential of a certain region. In order to model wind speed data smoothly, several statistical distributions have been studied. Truncated distributions are defined as a conditional distribution that results from restricting the domain of statistical distribution and they also cover base distribution. This paper proposes, for the first time, the use of upper-truncated Weibull distribution, in modeling wind speed data and also in estimating wind power density. In addition, a comparison is made between upper-truncated Weibull distribution and well known Weibull distribution using wind speed data measured in various regions of Turkey. The obtained results indicate that upper-truncated Weibull distribution shows better performance than Weibull distribution in estimating wind speed distribution and wind power. Therefore, upper-truncated Weibull distribution can be an alternative for use in the assessment of wind energy potential

Left atrial enlargement increases the risk of major adverse cardiac events independent of coronary vasodilator capacity

Energy Technology Data Exchange (ETDEWEB)

Koh, Angela S. [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); National Heart Centre Singapore, Singapore (Singapore); Murthy, Venkatesh L.; Sitek, Arkadiusz; Gayed, Peter; Bruyere, John; Di Carli, Marcelo F. [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Wu, Justina [Brigham and Women' s Hospital, Division of Cardiology, Department of Medicine, and the Noninvasive Cardiovascular Imaging Program, Departments of Medicine (Cardiology) and Radiology, Boston, MA (United States); Dorbala, Sharmila [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Brigham and Women' s Hospital, Department of Radiology and the Division of Cardiology, Noninvasive Cardiovascular Imaging Section, Boston, MA (United States)

2015-09-15

Longstanding uncontrolled atherogenic risk factors may contribute to left atrial (LA) hypertension, LA enlargement (LAE) and coronary vascular dysfunction. Together they may better identify risk of major adverse cardiac events (MACE). The aim of this study was to test the hypothesis that chronic LA hypertension as assessed by LAE modifies the relationship between coronary vascular function and MACE. In 508 unselected subjects with a normal clinical {sup 82}Rb PET/CT, ejection fraction ≥40 %, no prior coronary artery disease, valve disease or atrial fibrillation, LAE was determined based on LA volumes estimated from the hybrid perfusion and CT transmission scan images and indexed to body surface area. Absolute myocardial blood flow and global coronary flow reserve (CFR) were calculated. Subjects were systematically followed-up for the primary end-point - MACE - a composite of all-cause death, myocardial infarction, hospitalization for heart failure, stroke, coronary artery disease progression or revascularization. During a median follow-up of 862 days, 65 of the subjects experienced a composite event. Compared with subjects with normal LA size, subjects with LAE showed significantly lower CFR (2.25 ± 0.83 vs. 1.95 ± 0.80, p = 0.01). LAE independently and incrementally predicted MACE even after accounting for clinical risk factors, medication use, stress left ventricular ejection fraction, stress left ventricular end-diastolic volume index and CFR (chi-squared statistic increased from 30.9 to 48.3; p = 0.001). Among subjects with normal CFR, those with LAE had significantly worse event-free survival (risk adjusted HR 5.4, 95 % CI 2.3 - 12.8, p < 0.0001). LAE and reduced CFR are related but distinct cardiovascular adaptations to atherogenic risk factors. LAE is a risk marker for MACE independent of clinical factors and left ventricular volumes; individuals with LAE may be at risk of MACE despite normal coronary vascular function. (orig.)

New Schemes for Positive Real Truncation

Directory of Open Access Journals (Sweden)

Kari Unneland

2007-07-01

Full Text Available Model reduction, based on balanced truncation, of stable and of positive real systems are considered. An overview over some of the already existing techniques are given: Lyapunov balancing and stochastic balancing, which includes Riccati balancing. A novel scheme for positive real balanced truncation is then proposed, which is a combination of the already existing Lyapunov balancing and Riccati balancing. Using Riccati balancing, the solution of two Riccati equations are needed to obtain positive real reduced order systems. For the suggested method, only one Lyapunov equation and one Riccati equation are solved in order to obtain positive real reduced order systems, which is less computationally demanding. Further it is shown, that in order to get positive real reduced order systems, only one Riccati equation needs to be solved. Finally, this is used to obtain positive real frequency weighted balanced truncation.

Measuring a Truncated Disk in Aquila X-1

Science.gov (United States)

King, Ashley L.; Tomsick, John A.; Miller, Jon M.; Chenevez, Jerome; Barret, Didier; Boggs, Steven E.; Chakrabarty, Deepto; Christensen, Finn E.; Craig, William W.; Feurst, Felix;

Evolution of truncated moments of singlet parton distributions

International Nuclear Information System (INIS)

Forte, S.; Magnea, L.; Piccione, A.; Ridolfi, G.

2001-01-01

We define truncated Mellin moments of parton distributions by restricting the integration range over the Bjorken variable to the experimentally accessible subset x 0 ≤x≤1 of the allowed kinematic range 0≤x≤1. We derive the evolution equations satisfied by truncated moments in the general (singlet) case in terms of an infinite triangular matrix of anomalous dimensions which couple each truncated moment to all higher moments with orders differing by integers. We show that the evolution of any moment can be determined to arbitrarily good accuracy by truncating the system of coupled moments to a sufficiently large but finite size, and show how the equations can be solved in a way suitable for numerical applications. We discuss in detail the accuracy of the method in view of applications to precision phenomenology

Joint survival probability via truncated invariant copula

International Nuclear Information System (INIS)

Kim, Jeong-Hoon; Ma, Yong-Ki; Park, Chan Yeol

2016-01-01

Highlights: • We have studied an issue of dependence structure between default intensities. • We use a multivariate shot noise intensity process, where jumps occur simultaneously and their sizes are correlated. • We obtain the joint survival probability of the integrated intensities by using a copula. • We apply our theoretical result to pricing basket default swap spread. - Abstract: Given an intensity-based credit risk model, this paper studies dependence structure between default intensities. To model this structure, we use a multivariate shot noise intensity process, where jumps occur simultaneously and their sizes are correlated. Through very lengthy algebra, we obtain explicitly the joint survival probability of the integrated intensities by using the truncated invariant Farlie–Gumbel–Morgenstern copula with exponential marginal distributions. We also apply our theoretical result to pricing basket default swap spreads. This result can provide a useful guide for credit risk management.

The inter-relationship of diabetes and left ventricular systolic function on outcome after high-risk myocardial infarction

DEFF Research Database (Denmark)

Shah, Amil M; Uno, Hajime; Køber, Lars

2010-01-01

Diabetes is a potent risk factor for death and heart failure (HF) hospitalization following myocardial infarction (MI). Whether diabetes modifies the relationship between left ventricular ejection fraction (LVEF) and outcomes in the post-MI population is unknown.......Diabetes is a potent risk factor for death and heart failure (HF) hospitalization following myocardial infarction (MI). Whether diabetes modifies the relationship between left ventricular ejection fraction (LVEF) and outcomes in the post-MI population is unknown....

No evidence that protein truncating variants in BRIP1 are associated with breast cancer risk

DEFF Research Database (Denmark)

Easton, Douglas F; Lesueur, Fabienne; Decker, Brennan

2016-01-01

BACKGROUND: BRCA1 interacting protein C-terminal helicase 1 (BRIP1) is one of the Fanconi Anaemia Complementation (FANC) group family of DNA repair proteins. Biallelic mutations in BRIP1 are responsible for FANC group J, and previous studies have also suggested that rare protein truncating variants...

Data and performance profiles applying an adaptive truncation criterion, within linesearch-based truncated Newton methods, in large scale nonconvex optimization

Directory of Open Access Journals (Sweden)

Andrea Caliciotti

2018-04-01

Full Text Available In this paper, we report data and experiments related to the research article entitled “An adaptive truncation criterion, for linesearch-based truncated Newton methods in large scale nonconvex optimization” by Caliciotti et al. [1]. In particular, in Caliciotti et al. [1], large scale unconstrained optimization problems are considered by applying linesearch-based truncated Newton methods. In this framework, a key point is the reduction of the number of inner iterations needed, at each outer iteration, to approximately solving the Newton equation. A novel adaptive truncation criterion is introduced in Caliciotti et al. [1] to this aim. Here, we report the details concerning numerical experiences over a commonly used test set, namely CUTEst (Gould et al., 2015 [2]. Moreover, comparisons are reported in terms of performance profiles (Dolan and Moré, 2002 [3], adopting different parameters settings. Finally, our linesearch-based scheme is compared with a renowned trust region method, namely TRON (Lin and Moré, 1999 [4].

Conditional truncated plurigaussian simulation; Simulacao plurigaussiana truncada com condicionamento

Energy Technology Data Exchange (ETDEWEB)

Simon, Vitor Hugo

1997-12-01

The goal of this work was a development of an algorithm for the Truncated Plurigaussian Stochastic Simulation and its validation in a complex geologic model. The reservoir data comes from Aux Vases Zone at Rural Hill Field in Illinois, USA, and from the 2D geological interpretation, described by WEIMER et al. (1982), three sets of samples, with different grid densities ware taken. These sets were used to condition the simulation and to refine the estimates of the non-stationary matrix of facies proportions, used to truncate the gaussian random functions (RF). The Truncated Plurigaussian Model is an extension of the Truncated Gaussian Model (TG). In this new model its possible to use several facies with different spatial structures, associated with the simplicity of TG. The geological interpretation, used as a validation model, was chosen because it shows a set of NW/SE elongated tidal channels cutting the NE/SW shoreline deposits interleaved by impermeable facies. These characteristics of spatial structures of sedimentary facies served to evaluate the simulation model. Two independent gaussian RF were used, as well as an 'erosive model' as the truncation strategy. Also, non-conditional simulations were proceeded, using linearly combined gaussian RF with varying correlation coefficients. It was analyzed the influence of some parameters like: number of gaussian RF,correlation coefficient, truncations strategy, in the outcome of simulation, and also the physical meaning of these parameters under a geological point of view. It was showed, step by step, using an example, the theoretical model, and how to construct an algorithm to simulate with the Truncated Plurigaussian Model. The conclusion of this work was that even with a plain algorithm of the Conditional Truncated Plurigaussian and a complex geological model it's possible to obtain a usefulness product. (author)

Long-term prognostic value of risk scores after drug-eluting stent implantation for unprotected left main coronary artery: A pooled analysis of the ISAR-LEFT-MAIN and ISAR-LEFT-MAIN 2 randomized clinical trials.

Science.gov (United States)

Xhepa, Erion; Tada, Tomohisa; Kufner, Sebastian; Ndrepepa, Gjin; Byrne, Robert A; Kreutzer, Johanna; Ibrahim, Tareq; Tiroch, Klaus; Valgimigli, Marco; Tölg, Ralf; Cassese, Salvatore; Fusaro, Massimiliano; Schunkert, Heribert; Laugwitz, Karl L; Mehilli, Julinda; Kastrati, Adnan

2017-01-01

To evaluate the long-term prognostic value of risk scores in the setting of drug-eluting stent (DES) implantation for uLMCA. Data on the prognostic value of novel risk scores developed to select the most appropriate revascularization strategy in patients undergoing DES implantation for uLMCA disease are relatively limited. The study represents a patient-level pooled analysis of the ISAR-LEFT-MAIN (607 patients randomized to paclitaxel-eluting or sirolimus-eluting stents) and the ISAR-LEFT-MAIN-2 (650 patients randomized to everolimus-eluting or zotarolimus-eluting stents) randomized trials. The Syntax Score (SxScore) as well the Syntax Score II (SS-II), the EuroSCORE and the Global Risk Classification (GRC) were calculated. The primary outcome was all-cause mortality. At a mean follow-up of 3 years there were 160 deaths (12.7%). The death-incidence was significantly higher in the upper tertiles than in the intermediate or lower ones for all risk scores (log-rank test P risk scores were able to stratify the mortality risk at long-term follow-up. EuroSCORE was the only risk score that significantly improved the discriminatory power of a multivariable model to predict long-term mortality. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Differences in left and right carotid intima-media thickness and the associated risk factors

International Nuclear Information System (INIS)

Luo, X.; Yang, Y.; Cao, T.; Li, Z.

2011-01-01

Aim: To investigate the difference between the left and right carotid artery intima-media thickness (CIMT) with increasing age and to analyse the importance of the various risk factors associated with left and right CIMT, respectively. Materials and methods: Four hundred and forty-seven people were assigned into six groups based on age. CIMT and haemodynamic parameters of both carotid arteries were measured using the Quality Intima-Media Thickness (QIMT) technique. In addition, biochemical and anthropometric indices were also measured. Their associations were evaluated using simple and partial correlation analysis, adjusted for age. Results: Bilateral CIMTs became thicker with age (p < 0.001) and the left CIMT was significantly thicker compared with the right between the ages of 35 and 65 years (p = 0.01-0.05). In addition, the right CIMT thickened 10 years later compared with the left. Partial correlation analysis showed that the right CIMT correlated better with haemodynamic parameters compared with the left CIMT, but the left CIMT showed better correlation with biochemical indices. Conclusion: Haemodynamic and biochemical changes had different effects on the CIMT depending on the side affected. In addition, the left CIMT was thicker than the right between the ages of 35 and 65 years old.

Left atrial enlargement increases the risk of major adverse cardiac events independent of coronary vasodilator capacity.

Science.gov (United States)

Koh, Angela S; Murthy, Venkatesh L; Sitek, Arkadiusz; Gayed, Peter; Bruyere, John; Wu, Justina; Di Carli, Marcelo F; Dorbala, Sharmila

2015-09-01

Longstanding uncontrolled atherogenic risk factors may contribute to left atrial (LA) hypertension, LA enlargement (LAE) and coronary vascular dysfunction. Together they may better identify risk of major adverse cardiac events (MACE). The aim of this study was to test the hypothesis that chronic LA hypertension as assessed by LAE modifies the relationship between coronary vascular function and MACE. In 508 unselected subjects with a normal clinical (82)Rb PET/CT, ejection fraction ≥40 %, no prior coronary artery disease, valve disease or atrial fibrillation, LAE was determined based on LA volumes estimated from the hybrid perfusion and CT transmission scan images and indexed to body surface area. Absolute myocardial blood flow and global coronary flow reserve (CFR) were calculated. Subjects were systematically followed-up for the primary end-point - MACE - a composite of all-cause death, myocardial infarction, hospitalization for heart failure, stroke, coronary artery disease progression or revascularization. During a median follow-up of 862 days, 65 of the subjects experienced a composite event. Compared with subjects with normal LA size, subjects with LAE showed significantly lower CFR (2.25 ± 0.83 vs. 1.95 ± 0.80, p = 0.01). LAE independently and incrementally predicted MACE even after accounting for clinical risk factors, medication use, stress left ventricular ejection fraction, stress left ventricular end-diastolic volume index and CFR (chi-squared statistic increased from 30.9 to 48.3; p = 0.001). Among subjects with normal CFR, those with LAE had significantly worse event-free survival (risk adjusted HR 5.4, 95 % CI 2.3 - 12.8, p < 0.0001). LAE and reduced CFR are related but distinct cardiovascular adaptations to atherogenic risk factors. LAE is a risk marker for MACE independent of clinical factors and left ventricular volumes; individuals with LAE may be at risk of MACE despite normal coronary vascular function.

Truncation in diffraction pattern analysis. Pt. 1

International Nuclear Information System (INIS)

Delhez, R.; Keijser, T.H. de; Mittemeijer, E.J.; Langford, J.I.

1986-01-01

An evaluation of the concept of a line profile is provoked by truncation of the range of intensity measurement in practice. The measured truncated line profile can be considered either as part of the total intensity distribution which peaks at or near the reciprocal-lattice points (approach 1), or as part of a component line profile which is confined to a single reciprocal-lattice point (approach 2). Some false conceptions in line-profile analysis can then be avoided and recipes can be developed for the extrapolation of the tails of the truncated line profile. Fourier analysis of line profiles, according to the first approach, implies a Fourier series development of the total intensity distribution defined within [l - 1/2, l + 1/2] (l indicates the node considered in reciprocal space); the second approach implies a Fourier transformation of the component line profile defined within [ - ∞, + ∞]. Exact descriptions of size broadening are provided by both approaches, whereas combined size and strain broadening can only be evaluated adequately within the first approach. Straightforward methods are given for obtaining truncation-corrected values for the average crystallite size. (orig.)

Truncation Depth Rule-of-Thumb for Convolutional Codes

Science.gov (United States)

Moision, Bruce

2009-01-01

In this innovation, it is shown that a commonly used rule of thumb (that the truncation depth of a convolutional code should be five times the memory length, m, of the code) is accurate only for rate 1/2 codes. In fact, the truncation depth should be 2.5 m/(1 - r), where r is the code rate. The accuracy of this new rule is demonstrated by tabulating the distance properties of a large set of known codes. This new rule was derived by bounding the losses due to truncation as a function of the code rate. With regard to particular codes, a good indicator of the required truncation depth is the path length at which all paths that diverge from a particular path have accumulated the minimum distance of the code. It is shown that the new rule of thumb provides an accurate prediction of this depth for codes of varying rates.

Investigation of propagation dynamics of truncated vector vortex beams.

Science.gov (United States)

Srinivas, P; Perumangatt, C; Lal, Nijil; Singh, R P; Srinivasan, B

2018-06-01

In this Letter, we experimentally investigate the propagation dynamics of truncated vector vortex beams generated using a Sagnac interferometer. Upon focusing, the truncated vector vortex beam is found to regain its original intensity structure within the Rayleigh range. In order to explain such behavior, the propagation dynamics of a truncated vector vortex beam is simulated by decomposing it into the sum of integral charge beams with associated complex weights. We also show that the polarization of the truncated composite vector vortex beam is preserved all along the propagation axis. The experimental observations are consistent with theoretical predictions based on previous literature and are in good agreement with our simulation results. The results hold importance as vector vortex modes are eigenmodes of the optical fiber.

Blunt traumatic axillary artery truncation, in the absence of associated fracture.

Science.gov (United States)

Bokser, Emily; Caputo, William; Hahn, Barry; Greenstein, Josh

2018-02-01

Axillary artery injuries can be associated with both proximal humeral fractures (Naouli et al., 2016; Ng et al., 2016) [1,2] as well as shoulder dislocations (Leclerc et al., 2017; Karnes et al., 2016) [3,4]. We report a rare case of an isolated axillary artery truncation following blunt trauma without any associated fracture or dislocation. A 58-year-old male presented to the emergency department for evaluation after falling on his outstretched right arm. The patient was found to have an absent right radial pulse with decreased sensation to the right arm. Point of care ultrasound showed findings suspicious for traumatic axillary artery injury, and X-rays did not demonstrate any fracture. Computed tomography with angiography confirmed axillary artery truncation with active extravasation. The patient underwent successful vascular repair with an axillary artery bypass. Although extremity injuries are common in emergency departments, emergency physicians need to recognize the risk for vascular injuries, even without associated fracture or dislocation. Copyright © 2017 Elsevier Inc. All rights reserved.

Wigner distribution function of circularly truncated light beams

NARCIS (Netherlands)

Bastiaans, M.J.; Nijhawan, O.P.; Gupta, A.K.; Musla, A.K.; Singh, Kehar

1998-01-01

Truncating a light beam is expressed as a convolution of its Wigner distribution function and the WDF of the truncating aperture. The WDF of a circular aperture is derived and an approximate expression - which is exact in the space and the spatial-frequency origin and whose integral over the spatial

Flexible scheme to truncate the hierarchy of pure states.

Science.gov (United States)

Zhang, P-P; Bentley, C D B; Eisfeld, A

2018-04-07

The hierarchy of pure states (HOPS) is a wavefunction-based method that can be used for numerically modeling open quantum systems. Formally, HOPS recovers the exact system dynamics for an infinite depth of the hierarchy. However, truncation of the hierarchy is required to numerically implement HOPS. We want to choose a "good" truncation method, where by "good" we mean that it is numerically feasible to check convergence of the results. For the truncation approximation used in previous applications of HOPS, convergence checks are numerically challenging. In this work, we demonstrate the application of the "n-particle approximation" to HOPS. We also introduce a new approximation, which we call the "n-mode approximation." We then explore the convergence of these truncation approximations with respect to the number of equations required in the hierarchy in two exemplary problems: absorption and energy transfer of molecular aggregates.

Flexible scheme to truncate the hierarchy of pure states

Science.gov (United States)

Zhang, P.-P.; Bentley, C. D. B.; Eisfeld, A.

2018-04-01

The hierarchy of pure states (HOPS) is a wavefunction-based method that can be used for numerically modeling open quantum systems. Formally, HOPS recovers the exact system dynamics for an infinite depth of the hierarchy. However, truncation of the hierarchy is required to numerically implement HOPS. We want to choose a "good" truncation method, where by "good" we mean that it is numerically feasible to check convergence of the results. For the truncation approximation used in previous applications of HOPS, convergence checks are numerically challenging. In this work, we demonstrate the application of the "n-particle approximation" to HOPS. We also introduce a new approximation, which we call the "n-mode approximation." We then explore the convergence of these truncation approximations with respect to the number of equations required in the hierarchy in two exemplary problems: absorption and energy transfer of molecular aggregates.

Truncated predictor feedback for time-delay systems

CERN Document Server

Zhou, Bin

2014-01-01

This book provides a systematic approach to the design of predictor based controllers for (time-varying) linear systems with either (time-varying) input or state delays. Differently from those traditional predictor based controllers, which are infinite-dimensional static feedback laws and may cause difficulties in their practical implementation, this book develops a truncated predictor feedback (TPF) which involves only finite dimensional static state feedback. Features and topics: A novel approach referred to as truncated predictor feedback for the stabilization of (time-varying) time-delay systems in both the continuous-time setting and the discrete-time setting is built systematically Semi-global and global stabilization problems of linear time-delay systems subject to either magnitude saturation or energy constraints are solved in a systematic manner Both stabilization of a single system and consensus of a group of systems (multi-agent systems) are treated in a unified manner by applying the truncated pre...

New results to BDD truncation method for efficient top event probability calculation

International Nuclear Information System (INIS)

Mo, Yuchang; Zhong, Farong; Zhao, Xiangfu; Yang, Quansheng; Cui, Gang

2012-01-01

A Binary Decision Diagram (BDD) is a graph-based data structure that calculates an exact top event probability (TEP). It has been a very difficult task to develop an efficient BDD algorithm that can solve a large problem since its memory consumption is very high. Recently, in order to solve a large reliability problem within limited computational resources, Jung presented an efficient method to maintain a small BDD size by a BDD truncation during a BDD calculation. In this paper, it is first identified that Jung's BDD truncation algorithm can be improved for a more practical use. Then, a more efficient truncation algorithm is proposed in this paper, which can generate truncated BDD with smaller size and approximate TEP with smaller truncation error. Empirical results showed this new algorithm uses slightly less running time and slightly more storage usage than Jung's algorithm. It was also found, that designing a truncation algorithm with ideal features for every possible fault tree is very difficult, if not impossible. The so-called ideal features of this paper would be that with the decrease of truncation limits, the size of truncated BDD converges to the size of exact BDD, but should never be larger than exact BDD.

Maximum nondiffracting propagation distance of aperture-truncated Airy beams

Science.gov (United States)

Chu, Xingchun; Zhao, Shanghong; Fang, Yingwu

2018-05-01

Airy beams have called attention of many researchers due to their non-diffracting, self-healing and transverse accelerating properties. A key issue in research of Airy beams and its applications is how to evaluate their nondiffracting propagation distance. In this paper, the critical transverse extent of physically realizable Airy beams is analyzed under the local spatial frequency methodology. The maximum nondiffracting propagation distance of aperture-truncated Airy beams is formulated and analyzed based on their local spatial frequency. The validity of the formula is verified by comparing the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam, aperture-truncated exponentially decaying Airy beam and exponentially decaying Airy beam. Results show that the formula can be used to evaluate accurately the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam. Therefore, it can guide us to select appropriate parameters to generate Airy beams with long nondiffracting propagation distance that have potential application in the fields of laser weapons or optical communications.

An iterative reconstruction from truncated projection data

International Nuclear Information System (INIS)

Anon.

1985-01-01

Various methods have been proposed for tomographic reconstruction from truncated projection data. In this paper, a reconstructive method is discussed which consists of iterations of filtered back-projection, reprojection and some nonlinear processings. First, the method is so constructed that it converges to a fixed point. Then, to examine its effectiveness, comparisons are made by computer experiments with two existing reconstructive methods for truncated projection data, that is, the method of extrapolation based on the smooth assumption followed by filtered back-projection, and modified additive ART

Truncated Wigner dynamics and conservation laws

Science.gov (United States)

Drummond, Peter D.; Opanchuk, Bogdan

2017-10-01

Ultracold Bose gases can be used to experimentally test many-body theory predictions. Here we point out that both exact conservation laws and dynamical invariants exist in the topical case of the one-dimensional Bose gas, and these provide an important validation of methods. We show that the first four quantum conservation laws are exactly conserved in the approximate truncated Wigner approach to many-body quantum dynamics. Center-of-mass position variance is also exactly calculable. This is nearly exact in the truncated Wigner approximation, apart from small terms that vanish as N-3 /2 as N →∞ with fixed momentum cutoff. Examples of this are calculated in experimentally relevant, mesoscopic cases.

Pressure Overload by Transverse Aortic Constriction Induces Maladaptive Hypertrophy in a Titin-Truncated Mouse Model

Directory of Open Access Journals (Sweden)

Qifeng Zhou

2015-01-01

Full Text Available Mutations in the giant sarcomeric protein titin (TTN are a major cause for inherited forms of dilated cardiomyopathy (DCM. We have previously developed a mouse model that imitates a TTN truncation mutation we found in a large pedigree with DCM. While heterozygous Ttn knock-in mice do not display signs of heart failure under sedentary conditions, they recapitulate the human phenotype when exposed to the pharmacological stressor angiotensin II or isoproterenol. In this study we investigated the effects of pressure overload by transverse aortic constriction (TAC in heterozygous (Het Ttn knock-in mice. Two weeks after TAC, Het mice developed marked impairment of left ventricular ejection fraction (p<0.05, while wild-type (WT TAC mice did not. Het mice also trended toward increased ventricular end diastolic pressure and volume compared to WT littermates. We found an increase in histologically diffuse cardiac fibrosis in Het compared to WT in TAC mice. This study shows that a pattern of DCM can be induced by TAC-mediated pressure overload in a TTN-truncated mouse model. This model enlarges our arsenal of cardiac disease models, adding a valuable tool to understand cardiac pathophysiological remodeling processes and to develop therapeutic approaches to combat heart failure.

Acceptance Sampling Plans Based on Truncated Life Tests for Sushila Distribution

Directory of Open Access Journals (Sweden)

Amer Ibrahim Al-Omari

2018-03-01

Full Text Available An acceptance sampling plan problem based on truncated life tests when the lifetime following a Sushila distribution is considered in this paper. For various acceptance numbers, confidence levels and values of the ratio between fixed experiment time and particular mean lifetime, the minimum sample sizes required to ascertain a specified mean life were found. The operating characteristic function values of the suggested sampling plans and the producer’s risk are presented. Some tables are provided and the results are illustrated by an example of a real data set.

Immature truncated O-glycophenotype of cancer directly induces oncogenic features

DEFF Research Database (Denmark)

Radhakrishnan, Prakash; Dabelsteen, Sally; Madsen, Frey Brus

2014-01-01

Aberrant expression of immature truncated O-glycans is a characteristic feature observed on virtually all epithelial cancer cells, and a very high frequency is observed in early epithelial premalignant lesions that precede the development of adenocarcinomas. Expression of the truncated O-glycan s...

Impact of degree truncation on the spread of a contagious process on networks.

Science.gov (United States)

Harling, Guy; Onnela, Jukka-Pekka

2018-03-01

Understanding how person-to-person contagious processes spread through a population requires accurate information on connections between population members. However, such connectivity data, when collected via interview, is often incomplete due to partial recall, respondent fatigue or study design, e.g., fixed choice designs (FCD) truncate out-degree by limiting the number of contacts each respondent can report. Past research has shown how FCD truncation affects network properties, but its implications for predicted speed and size of spreading processes remain largely unexplored. To study the impact of degree truncation on predictions of spreading process outcomes, we generated collections of synthetic networks containing specific properties (degree distribution, degree-assortativity, clustering), and also used empirical social network data from 75 villages in Karnataka, India. We simulated FCD using various truncation thresholds and ran a susceptible-infectious-recovered (SIR) process on each network. We found that spreading processes propagated on truncated networks resulted in slower and smaller epidemics, with a sudden decrease in prediction accuracy at a level of truncation that varied by network type. Our results have implications beyond FCD to truncation due to any limited sampling from a larger network. We conclude that knowledge of network structure is important for understanding the accuracy of predictions of process spread on degree truncated networks.

Computational Fluid Dynamic Analysis of the Left Atrial Appendage to Predict Thrombosis Risk

Directory of Open Access Journals (Sweden)

Giorgia Maria Bosi

2018-04-01

Full Text Available During Atrial Fibrillation (AF more than 90% of the left atrial thrombi responsible for thromboembolic events originate in the left atrial appendage (LAA, a complex small sac protruding from the left atrium (LA. Current available treatments to prevent thromboembolic events are oral anticoagulation, surgical LAA exclusion, or percutaneous LAA occlusion. However, the mechanism behind thrombus formation in the LAA is poorly understood. The aim of this work is to analyse the hemodynamic behaviour in four typical LAA morphologies - “Chicken wing”, “Cactus”, “Windsock” and “Cauliflower” - to identify potential relationships between the different shapes and the risk of thrombotic events. Computerised tomography (CT images from four patients with no LA pathology were segmented to derive the 3D anatomical shape of LAA and LA. Computational Fluid Dynamic (CFD analyses based on the patient-specific anatomies were carried out imposing both healthy and AF flow conditions. Velocity and shear strain rate (SSR were analysed for all cases. Residence time in the different LAA regions was estimated with a virtual contrast agent washing out. CFD results indicate that both velocity and SSR decrease along the LAA, from the ostium to the tip, at each instant in the cardiac cycle, thus making the LAA tip more prone to fluid stagnation, and therefore to thrombus formation. Velocity and SSR also decrease from normal to AF conditions. After four cardiac cycles, the lowest washout of contrast agent was observed for the Cauliflower morphology (3.27% of residual contrast in AF, and the highest for the Windsock (0.56% of residual contrast in AF. This suggests that the former is expected to be associated with a higher risk of thrombosis, in agreement with clinical reports in the literature. The presented computational models highlight the major role played by the LAA morphology on the hemodynamics, both in normal and AF conditions, revealing the potential

Application of a truncated normal failure distribution in reliability testing

Science.gov (United States)

Groves, C., Jr.

1968-01-01

Statistical truncated normal distribution function is applied as a time-to-failure distribution function in equipment reliability estimations. Age-dependent characteristics of the truncated function provide a basis for formulating a system of high-reliability testing that effectively merges statistical, engineering, and cost considerations.

Coronary artery calcification and ECG pattern of left ventricular hypertrophy or strain identify different healthy individuals at risk

DEFF Research Database (Denmark)

Diederichsen, Søren Zöga; Gerke, Oke; Olsen, Michael Hecht

2013-01-01

PURPOSE:: To improve risk stratification for development of ischaemic heart disease, several markers have been proposed. Both the presence of coronary artery calcification (CAC) and ECG pattern of left ventricular hypertrophy/strain have been shown to provide independent prognostic information....... In this study, we investigated the association between established risk factors, ECG measurements and the presence of coronary artery calcification. METHOD:: A random sample of healthy men and women aged 50 or 60 years were invited to the screening study. Established risk factors were measured. A noncontrast...... computed tomographic (CT) scan was performed to assess the CAC score. ECG analysis included left ventricular hypertrophy (LVH) using the Sokolow-Lyon criteria and the Cornell voltage × QRS duration product, and strain pattern based on ST segment depression and T-wave abnormalities. The association between...

Truncation scheme of time-dependent density-matrix approach II

Energy Technology Data Exchange (ETDEWEB)

Tohyama, Mitsuru [Kyorin University School of Medicine, Mitaka, Tokyo (Japan); Schuck, Peter [Institut de Physique Nucleaire, IN2P3-CNRS, Universite Paris-Sud, Orsay (France); Laboratoire de Physique et de Modelisation des Milieux Condenses, CNRS et Universite Joseph Fourier, Grenoble (France)

2017-09-15

A truncation scheme of the Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy for reduced density matrices, where a three-body density matrix is approximated by two-body density matrices, is improved to take into account a normalization effect. The truncation scheme is tested for the Lipkin model. It is shown that the obtained results are in good agreement with the exact solutions. (orig.)

Multiple-scattering theory with a truncated basis set

International Nuclear Information System (INIS)

Zhang, X.; Butler, W.H.

1992-01-01

Multiple-scattering theory (MST) is an extremely efficient technique for calculating the electronic structure of an assembly of atoms. The wave function in MST is expanded in terms of spherical waves centered on each atom and indexed by their orbital and azimuthal quantum numbers, l and m. The secular equation which determines the characteristic energies can be truncated at a value of the orbital angular momentum l max , for which the higher angular momentum phase shifts, δ l (l>l max ), are sufficiently small. Generally, the wave-function coefficients which are calculated from the secular equation are also truncated at l max . Here we point out that this truncation of the wave function is not necessary and is in fact inconsistent with the truncation of the secular equation. A consistent procedure is described in which the states with higher orbital angular momenta are retained but with their phase shifts set to zero. We show that this treatment gives smooth, continuous, and correctly normalized wave functions and that the total charge density calculated from the corresponding Green function agrees with the Lloyd formula result. We also show that this augmented wave function can be written as a linear combination of Andersen's muffin-tin orbitals in the case of muffin-tin potentials, and can be used to generalize the muffin-tin orbital idea to full-cell potentals

Left atrial systolic force in hypertensive patients with left ventricular hypertrophy: the LIFE study

DEFF Research Database (Denmark)

Chinali, M.; Simone, G. de; Wachtell, K.

2008-01-01

In hypertensive patients without prevalent cardiovascular disease, enhanced left atrial systolic force is associated with left ventricular hypertrophy and increased preload. It also predicts cardiovascular events in a population with high prevalence of obesity. Relations between left atrial...... systolic force and left ventricular geometry and function have not been investigated in high-risk hypertrophic hypertensive patients. Participants in the Losartan Intervention For Endpoint reduction in hypertension echocardiography substudy without prevalent cardiovascular disease or atrial fibrillation (n...... = 567) underwent standard Doppler echocardiography. Left atrial systolic force was obtained from the mitral orifice area and Doppler mitral peak A velocity. Patients were divided into groups with normal or increased left atrial systolic force (>14.33 kdyn). Left atrial systolic force was high in 297...

Importance-truncated shell model for multi-shell valence spaces

Energy Technology Data Exchange (ETDEWEB)

Stumpf, Christina; Vobig, Klaus; Roth, Robert [Institut fuer Kernphysik, TU Darmstadt (Germany)

2016-07-01

The valence-space shell model is one of the work horses in nuclear structure theory. In traditional applications, shell-model calculations are carried out using effective interactions constructed in a phenomenological framework for rather small valence spaces, typically spanned by one major shell. We improve on this traditional approach addressing two main aspects. First, we use new effective interactions derived in an ab initio approach and, thus, establish a connection to the underlying nuclear interaction providing access to single- and multi-shell valence spaces. Second, we extend the shell model to larger valence spaces by applying an importance-truncation scheme based on a perturbative importance measure. In this way, we reduce the model space to the relevant basis states for the description of a few target eigenstates and solve the eigenvalue problem in this physics-driven truncated model space. In particular multi-shell valence spaces are not tractable otherwise. We combine the importance-truncated shell model with refined extrapolation schemes to approximately recover the exact result. We present first results obtained in the importance-truncated shell model with the newly derived ab initio effective interactions for multi-shell valence spaces, e.g., the sdpf shell.

Flow equation of quantum Einstein gravity in a higher-derivative truncation

International Nuclear Information System (INIS)

Lauscher, O.; Reuter, M.

2002-01-01

Motivated by recent evidence indicating that quantum Einstein gravity (QEG) might be nonperturbatively renormalizable, the exact renormalization group equation of QEG is evaluated in a truncation of theory space which generalizes the Einstein-Hilbert truncation by the inclusion of a higher-derivative term (R 2 ). The beta functions describing the renormalization group flow of the cosmological constant, Newton's constant, and the R 2 coupling are computed explicitly. The fixed point properties of the 3-dimensional flow are investigated, and they are confronted with those of the 2-dimensional Einstein-Hilbert flow. The non-Gaussian fixed point predicted by the latter is found to generalize to a fixed point on the enlarged theory space. In order to test the reliability of the R 2 truncation near this fixed point we analyze the residual scheme dependence of various universal quantities; it turns out to be very weak. The two truncations are compared in detail, and their numerical predictions are found to agree with a surprisingly high precision. Because of the consistency of the results it appears increasingly unlikely that the non-Gaussian fixed point is an artifact of the truncation. If it is present in the exact theory QEG is probably nonperturbatively renormalizable and ''asymptotically safe.'' We discuss how the conformal factor problem of Euclidean gravity manifests itself in the exact renormalization group approach and show that, in the R 2 truncation, the investigation of the fixed point is not afflicted with this problem. Also the Gaussian fixed point of the Einstein-Hilbert truncation is analyzed; it turns out that it does not generalize to a corresponding fixed point on the enlarged theory space

Approximate truncation robust computed tomography—ATRACT

International Nuclear Information System (INIS)

Dennerlein, Frank; Maier, Andreas

2013-01-01

We present an approximate truncation robust algorithm to compute tomographic images (ATRACT). This algorithm targets at reconstructing volumetric images from cone-beam projections in scenarios where these projections are highly truncated in each dimension. It thus facilitates reconstructions of small subvolumes of interest, without involving prior knowledge about the object. Our method is readily applicable to medical C-arm imaging, where it may contribute to new clinical workflows together with a considerable reduction of x-ray dose. We give a detailed derivation of ATRACT that starts from the conventional Feldkamp filtered-backprojection algorithm and that involves, as one component, a novel original formula for the inversion of the two-dimensional Radon transform. Discretization and numerical implementation are discussed and reconstruction results from both, simulated projections and first clinical data sets are presented. (paper)

Stellar Disk Truncations: HI Density and Dynamics

Science.gov (United States)

Trujillo, Ignacio; Bakos, Judit

2010-06-01

Using HI Nearby Galaxy Survey (THINGS) 21-cm observations of a sample of nearby (nearly face-on) galaxies we explore whether the stellar disk truncation phenomenon produces any signature either in the HI gas density and/or in the gas dynamics. Recent cosmological simulations suggest that the origin of the break on the surface brightness distribution is produced by the appearance of a warp at the truncation position. This warp should produce a flaring on the gas distribution increasing the velocity dispersion of the HI component beyond the break. We do not find, however, any evidence of this increase in the gas velocity dispersion profile.

Correction: No Child Left Alone: Moral Judgments about Parents Affect Estimates of Risk to Children

Directory of Open Access Journals (Sweden)

Ashley J. Thomas

2016-10-01

Full Text Available This article details a correction to article Thomas, A. J., Stanford, P. K., & Sarnecka, B. W. (2016. No Child Left Alone: Moral Judgments about Parents Affect Estimates of Risk to Children. 'Collabra', 2(1, 10. DOI: http://doi.org/10.1525/collabra.33

Enhancing propagation characteristics of truncated localized waves in silica

KAUST Repository

Salem, Mohamed

2011-07-01

The spectral characteristics of truncated Localized Waves propagating in dispersive silica are analyzed. Numerical experiments show that the immunity of the truncated Localized Waves propagating in dispersive silica to decay and distortion is enhanced as the non-linearity of the relation between the transverse spatial spectral components and the wave vector gets stronger, in contrast to free-space propagating waves, which suffer from early decay and distortion. © 2011 IEEE.

Scavenger receptor AI/II truncation, lung function and COPD: a large population-based study

DEFF Research Database (Denmark)

Thomsen, M; Nordestgaard, B G; Tybjærg-Hansen, Anne

2011-01-01

The scavenger receptor A-I/II (SRA-I/II) on alveolar macrophages is involved in recognition and clearance of modified lipids and inhaled particulates. A rare variant of the SRA-I/II gene, Arg293X, truncates the distal collagen-like domain, which is essential for ligand recognition. We tested...... whether the Arg293X variant is associated with reduced lung function and risk of chronic obstructive pulmonary disease (COPD) in the general population....

Truncation of CPC solar collectors and its effect on energy collection

Science.gov (United States)

Carvalho, M. J.; Collares-Pereira, M.; Gordon, J. M.; Rabl, A.

1985-01-01

Analytic expressions are derived for the angular acceptance function of two-dimensional compound parabolic concentrator solar collectors (CPC's) of arbitrary degree of truncation. Taking into account the effect of truncation on both optical and thermal losses in real collectors, the increase in monthly and yearly collectible energy is also evaluated. Prior analyses that have ignored the correct behavior of the angular acceptance function at large angles for truncated collectors are shown to be in error by 0-2 percent in calculations of yearly collectible energy for stationary collectors.

Modeling the Link between Left Ventricular Flow and Thromboembolic Risk Using Lagrangian Coherent Structures

Directory of Open Access Journals (Sweden)

Karen May-Newman

2016-11-01

Full Text Available A thrombus is a blood clot that forms on a surface, and can grow and detach, presenting a high risk for stroke and pulmonary embolism. This risk increases with blood-contacting medical devices, due to the immunological response to foreign surfaces and altered flow patterns that activate the blood and promote thromboembolism (TE. Abnormal blood transport, including vortex behavior and regional stasis, can be assessed from Lagrangian Coherent Structures (LCS. LCS are flow structures that bound transport within a flow field and divide the flow into regions with maximally attracting/repelling surfaces that maximize local shear. LCS can be identified from finite time Lyapunov exponent (FTLE fields, which are computed from velocity field data. In this study, the goal was to use FTLE analysis to evaluate LCS in the left ventricle (LV using velocity data obtained from flow visualization of a mock circulatory loop. A model of dilated cardiomyopathy (DCM was used to investigate the effect of left ventricular assist device (LVAD support on diastolic filling and transport in the LV. A small thrombus in the left ventricular outflow tract was also considered using data from a corresponding LV model. The DCM LV exhibited a direct flow of 0.8 L/cardiac cycle, which was tripled during LVAD support Delayed ejection flow was doubled, further illustrating the impact of LVAD support on blood transport. An examination of the attracting LCS ridges during diastolic filling showed that the increase is due primarily to augmentation of A wave inflow, which is associated with increased vortex circulation, kinetic energy and Forward FTLE. The introduction of a small thrombus in the left ventricular outflow tract (LVOT of the LV had a minimal effect on diastolic inflow, but obstructed systolic outflow leading to decreased transport compared with the unobstructed LVOT geometry. Localized FTLE in the LVOT increased dramatically with the small thrombus model, which reflects

The inter-relationship of diabetes and left ventricular systolic function on outcome after high-risk myocardial infarction

DEFF Research Database (Denmark)

Shah, Amil M; Uno, Hajime; Køber, Lars

2010-01-01

Diabetes is a potent risk factor for death and heart failure (HF) hospitalization following myocardial infarction (MI). Whether diabetes modifies the relationship between left ventricular ejection fraction (LVEF) and outcomes in the post-MI population is unknown....

Transiently truncated and differentially regulated expression of midkine during mouse embryogenesis

International Nuclear Information System (INIS)

Chen Qin; Yuan Yuanyang; Lin Shuibin; Chang Youde; Zhuo Xinming; Wei Wei; Tao Ping; Ruan Lingjuan; Li Qifu; Li Zhixing

2005-01-01

Midkine (MK) is a retinoic acid response cytokine, mostly expressed in embryonic tissues. Aberrant expression of MK was found in numerous cancers. In human, a truncated MK was expressed specifically in tumor/cancer tissues. Here we report the discovery of a novel truncated form of MK transiently expressed during normal mouse embryonic development. In addition, MK is concentrated at the interface between developing epithelium and mesenchyme as well as highly proliferating cells. Its expression, which is closely coordinated with angiogenesis and vasculogenesis, is spatiotemporally regulated with peaks in extensive organogenesis period and undifferentiated cells tailing off in maturing cells, implying its role in nascent blood vessel (endothelial) signaling of tissue differentiation and stem cell renewal/differentiation.. Cloning and sequencing analysis revealed that the embryonic truncated MK, in which the conserved domain is in-frame deleted, presumably producing a novel secreted small peptide, is different from the truncated form in human cancer tissues, whose deletion results in a frame-shift mutation. Our data suggest that MK may play a role in epithelium-mesenchyme interactions, blood vessel signaling, and the decision of proliferation vs differentiation. Detection of the transiently expressed truncated MK reveals its novel function in development and sheds light on its role in carcinogenesis

Modifications of Geometric Truncation of the Scattering Phase Function

Science.gov (United States)

Radkevich, A.

2017-12-01

Phase function (PF) of light scattering on large atmospheric particles has very strong peak in forward direction constituting a challenge for accurate numerical calculations of radiance. Such accurate (and fast) evaluations are important in the problems of remote sensing of the atmosphere. Scaling transformation replaces original PF with a sum of the delta function and a new regular smooth PF. A number of methods to construct such a PF were suggested. Delta-M and delta-fit methods require evaluation of the PF moments which imposes a numerical problem if strongly anisotropic PF is given as a function of angle. Geometric truncation keeps the original PF unchanged outside the forward peak cone replacing it with a constant within the cone. This approach is designed to preserve the asymmetry parameter. It has two disadvantages: 1) PF has discontinuity at the cone; 2) the choice of the cone is subjective, no recommendations were provided on the choice of the truncation angle. This choice affects both truncation fraction and the value of the phase function within the forward cone. Both issues are addressed in this study. A simple functional form of the replacement PF is suggested. This functional form allows for a number of modifications. This study consider 3 versions providing continuous PF. The considered modifications also bear either of three properties: preserve asymmetry parameter, provide continuity of the 1st derivative of the PF, and preserve mean scattering angle. The second problem mentioned above is addressed with a heuristic approach providing unambiguous criterion of selection of the truncation angle. The approach showed good performance on liquid water and ice clouds with different particle size distributions. Suggested modifications were tested on different cloud PFs using both discrete ordinates and Monte Carlo methods. It was showed that the modifications provide better accuracy of the radiance computation compare to the original geometric truncation.

Propagation of truncated modified Laguerre-Gaussian beams

Science.gov (United States)

Deng, D.; Li, J.; Guo, Q.

2010-01-01

By expanding the circ function into a finite sum of complex Gaussian functions and applying the Collins formula, the propagation of hard-edge diffracted modified Laguerre-Gaussian beams (MLGBs) through a paraxial ABCD system is studied, and the approximate closed-form propagation expression of hard-edge diffracted MLGBs is obtained. The transverse intensity distribution of the MLGB carrying finite power can be characterized by a single bright and symmetric ring during propagation when the aperture radius is very large. Starting from the definition of the generalized truncated second-order moments, the beam quality factor of MLGBs through a hard-edged circular aperture is investigated in a cylindrical coordinate system, which turns out to be dependent on the truncated radius and the beam orders.

Balanced truncation for linear switched systems

DEFF Research Database (Denmark)

Petreczky, Mihaly; Wisniewski, Rafal; Leth, John-Josef

2013-01-01

In this paper, we present a theoretical analysis of the model reduction algorithm for linear switched systems from Shaker and Wisniewski (2011, 2009) and . This algorithm is a reminiscence of the balanced truncation method for linear parameter varying systems (Wood et al., 1996) [3]. Specifically...

Truncated Newton-Raphson Methods for Quasicontinuum Simulations

National Research Council Canada - National Science Library

Liang, Yu; Kanapady, Ramdev; Chung, Peter W

2006-01-01

.... In this research, we report the effectiveness of the truncated Newton-Raphson method and quasi-Newton method with low-rank Hessian update strategy that are evaluated against the full Newton-Raphson...

The Stars and Gas in Outer Parts of Galaxy Disks : Extended or Truncated, Flat or Warped?

NARCIS (Netherlands)

van der Kruit, P. C.; Funes, JG; Corsini, EM

2008-01-01

I review observations of truncations of stellar disks and models for their origin, compare observations of truncations in moderately inclined galaxies to those in edge-on systems and discuss the relation between truncations and H I-warps and their systematics and origin. Truncations are a common

On truncated Taylor series and the position of their spurious zeros

DEFF Research Database (Denmark)

Christiansen, Søren; Madsen, Per A.

2006-01-01

A truncated Taylor series, or a Taylor polynomial, which may appear when treating the motion of gravity water waves, is obtained by truncating an infinite Taylor series for a complex, analytical function. For such a polynomial the position of the complex zeros is considered in case the Taylor...

Study of the variations of fall induced hip fracture risk between right and left femurs using CT-based FEA.

Science.gov (United States)

Faisal, Tanvir R; Luo, Yunhua

2017-10-03

Hip fracture of elderly people-suffering from osteoporosis-is a severe public health concern, which can be reduced by providing a prior assessment of hip fracture risk. Image-based finite element analysis (FEA) has been considered an effective computational tool to assess the hip fracture risk. Considering the femoral neck region is the weakest, fracture risk indicators (FRI) are evaluated for both single-legged stance and sideways fall configurations and are compared between left and right femurs of each subject. Quantitative Computed Tomography (QCT) scan datasets of thirty anonymous patients' left and right femora have been considered for the FE models, which have been simulated with an equal magnitude of load applied to the aforementioned configurations. The requirement of bilateral hip assessment in predicting the fracture risk has been explored in this study. Comparing the sideways fall and single-legged stance, the FRI varies by 64 to 74% at the superior aspects and by 14 to 19% at the inferior surfaces of both the femora. The results of this in vivo analysis clearly substantiate that the fracture is expected to initiate at the superior surface of femoral neck region if a patient falls from his/her standing height. The distributions of FRI between the femurs vary considerably, and the variability is significant at the superior aspects. The p value (= 0.02) obtained from paired sample t-Test yields p value ≤ 0.05, which shows the evidence of variability of the FRI distribution between left and right femurs. Moreover, the comparison of FRIs between the left and right femur of men and women shows that women are more susceptible to hip fracture than men. The results and statistical variation clearly signify a need for bilateral hip scanning in predicting hip fracture risk, which is clinically conducted, at present, based on one hip chosen randomly and may lead to inaccurate fracture prediction. This study, although preliminary, may play a crucial role in

Closed-form kinetic parameter estimation solution to the truncated data problem

International Nuclear Information System (INIS)

Zeng, Gengsheng L; Kadrmas, Dan J; Gullberg, Grant T

2010-01-01

In a dedicated cardiac single photon emission computed tomography (SPECT) system, the detectors are focused on the heart and the background is truncated in the projections. Reconstruction using truncated data results in biased images, leading to inaccurate kinetic parameter estimates. This paper has developed a closed-form kinetic parameter estimation solution to the dynamic emission imaging problem. This solution is insensitive to the bias in the reconstructed images that is caused by the projection data truncation. This paper introduces two new ideas: (1) it includes background bias as an additional parameter to estimate, and (2) it presents a closed-form solution for compartment models. The method is based on the following two assumptions: (i) the amount of the bias is directly proportional to the truncated activities in the projection data, and (ii) the background concentration is directly proportional to the concentration in the myocardium. In other words, the method assumes that the image slice contains only the heart and the background, without other organs, that the heart is not truncated, and that the background radioactivity is directly proportional to the radioactivity in the blood pool. As long as the background activity can be modeled, the proposed method is applicable regardless of the number of compartments in the model. For simplicity, the proposed method is presented and verified using a single compartment model with computer simulations using both noiseless and noisy projections.

Analytic reconstruction algorithms for triple-source CT with horizontal data truncation

International Nuclear Information System (INIS)

Chen, Ming; Yu, Hengyong

2015-01-01

Purpose: This paper explores a triple-source imaging method with horizontal data truncation to enlarge the field of view (FOV) for big objects. Methods: The study is conducted by using theoretical analysis, mathematical deduction, and numerical simulations. The proposed algorithms are implemented in c + + and MATLAB. While the basic platform is constructed in MATLAB, the computationally intensive segments are coded in c + +, which are linked via a MEX interface. Results: A triple-source circular scanning configuration with horizontal data truncation is developed, where three pairs of x-ray sources and detectors are unevenly distributed on the same circle to cover the whole imaging object. For this triple-source configuration, a fan-beam filtered backprojection-type algorithm is derived for truncated full-scan projections without data rebinning. The algorithm is also extended for horizontally truncated half-scan projections and cone-beam projections in a Feldkamp-type framework. Using their method, the FOV is enlarged twofold to threefold to scan bigger objects with high speed and quality. The numerical simulation results confirm the correctness and effectiveness of the developed algorithms. Conclusions: The triple-source scanning configuration with horizontal data truncation cannot only keep most of the advantages of a traditional multisource system but also cover a larger FOV for big imaging objects. In addition, because the filtering is shift-invariant, the proposed algorithms are very fast and easily parallelized on graphic processing units

Timing of the Cenozoic basins of Southern Mexico and its relationship with the Pacific truncation process: Subduction erosion or detachment of the Chortís block

Science.gov (United States)

Silva-Romo, Gilberto; Mendoza-Rosales, Claudia Cristina; Campos-Madrigal, Emiliano; Hernández-Marmolejo, Yoalli Bianii; de la Rosa-Mora, Orestes Antonio; de la Torre-González, Alam Israel; Bonifacio-Serralde, Carlos; López-García, Nallely; Nápoles-Valenzuela, Juan Ivan

2018-04-01

In the central sector of the Sierra Madre del Sur in Southern Mexico, between approximately 36 and 16 Ma ago and in the west to east direction, a diachronic process of the formation of ∼north-south trending fault-bounded basins occurred. No tectono-sedimentary event in the period between 25 and 20 Ma is recognized in the study region. A period during which subduction erosion truncated the continental crust of southern Mexico has been proposed. The chronology, geometry and style of the formation of the Eocene Miocene fault-bounded basins are more congruent with crustal truncation by the detachment of the Chortís block, thus bringing into question the crustal truncation hypothesis of the Southern Mexico margin. Between Taxco and Tehuacán, using seven new Laser Ablation- Inductively-coupled plasma mass spectrometry (LA-ICP-MS) U-Pb ages in magmatic zircons, we refine the stratigraphy of the Tepenene, Tehuitzingo, Atzumba and Tepelmeme basins. The analyzed basins present similar tectono-sedimentary evolutions as follows: Stage 1, depocenter formation and filling by clastic rocks accumulated as alluvial fans and Stage 2, lacustrine sedimentation characterized by calcareous and/or evaporite beds. Based on our results, we propose the following hypothesis: in Southern Mexico, during Eocene-Miocene times, the diachronic formation of fault-bounded basins with general north-south trend occurred within the framework of the convergence between the plates of North and South America, and once the Chortís block had slipped towards the east, the basins formed in the cortical crust were recently left behind. On the other hand, the beginning of the basins' formation process related to left strike slip faults during Eocene-Oligocene times can be associated with the thermomechanical maturation cortical process that caused the brittle/ductile transition level in the continental crust to shallow.

A Line Search Multilevel Truncated Newton Algorithm for Computing the Optical Flow

Directory of Open Access Journals (Sweden)

Lluís Garrido

2015-06-01

Full Text Available We describe the implementation details and give the experimental results of three optimization algorithms for dense optical flow computation. In particular, using a line search strategy, we evaluate the performance of the unilevel truncated Newton method (LSTN, a multiresolution truncated Newton (MR/LSTN and a full multigrid truncated Newton (FMG/LSTN. We use three image sequences and four models of optical flow for performance evaluation. The FMG/LSTN algorithm is shown to lead to better optical flow estimation with less computational work than both the LSTN and MR/LSTN algorithms.

Left atrial accessory appendages, diverticula, and left-sided septal pouch in multi-slice computed tomography. Association with atrial fibrillation and cerebrovascular accidents.

Science.gov (United States)

Hołda, Mateusz K; Koziej, Mateusz; Wszołek, Karolina; Pawlik, Wiesław; Krawczyk-Ożóg, Agata; Sorysz, Danuta; Łoboda, Piotr; Kuźma, Katarzyna; Kuniewicz, Marcin; Lelakowski, Jacek; Dudek, Dariusz; Klimek-Piotrowska, Wiesława

2017-10-01

The aim of this study is to provide a morphometric description of the left-sided septal pouch (LSSP), left atrial accessory appendages, and diverticula using cardiac multi-slice computed tomography (MSCT) and to compare results between patient subgroups. Two hundred and ninety four patients (42.9% females) with a mean of 69.4±13.1years of age were investigated using MSCT. The presence of the LSSP, left atrial accessory appendages, and diverticula was evaluated. Multiple logistic regression analysis was performed to check whether the presence of additional left atrial structures is associated with increased risk of atrial fibrillation and cerebrovascular accidents. At least one additional left atrial structure was present in 51.7% of patients. A single LSSP, left atrial diverticulum, and accessory appendage were present in 35.7%, 16.0%, and 4.1% of patients, respectively. After adjusting for other risk factors via multiple logistic regression, patients with LSSP are more likely to have atrial fibrillation (OR=2.00, 95% CI=1.14-3.48, p=0.01). The presence of a LSSP was found to be associated with an increased risk of transient ischemic attack using multiple logistic regression analysis after adjustment for other risk factors (OR=3.88, 95% CI=1.10-13.69, p=0.03). In conclusion LSSPs, accessory appendages, and diverticula are highly prevalent anatomic structures within the left atrium, which could be easily identified by MSCT. The presence of LSSP is associated with increased risk for atrial fibrillation and transient ischemic attack. Copyright © 2017 Elsevier B.V. All rights reserved.

Low-mode truncation methods in the sine-Gordon equation

International Nuclear Information System (INIS)

Xiong Chuyu.

1991-01-01

In this dissertation, the author studies the chaotic and coherent motions (i.e., low-dimensional chaotic attractor) in some near integrable partial differential equations, particularly the sine-Gordon equation and the nonlinear Schroedinger equation. In order to study the motions, he uses low mode truncation methods to reduce these partial differential equations to some truncated models (low-dimensional ordinary differential equations). By applying many methods available to low-dimensional ordinary differential equations, he can understand the low-dimensional chaotic attractor of PDE's much better. However, there are two important questions one needs to answer: (1) How many modes is good enough for the low mode truncated models to capture the dynamics uniformly? (2) Is the chaotic attractor in a low mode truncated model close to the chaotic attractor in the original PDE? And how close is? He has developed two groups of powerful methods to help to answer these two questions. They are the computation methods of continuation and local bifurcation, and local Lyapunov exponents and Lyapunov exponents. Using these methods, he concludes that the 2N-nls ODE is a good model for the sine-Gordon equation and the nonlinear Schroedinger equation provided one chooses a 'good' basis and uses 'enough' modes (where 'enough' depends on the parameters of the system but is small for the parameter studied here). Therefore, one can use 2N-nls ODE to study the chaos of PDE's in more depth

Relationship of left ventricular systolic function to persistence or development of electrocardiographic left ventricular hypertrophy in hypertensive patients

DEFF Research Database (Denmark)

Okin, Peter M; Wachtell, Kristian; Gerdts, Eva

2014-01-01

left ventricular systolic function in patients with new or persistent ECG LVH. METHODS: Baseline and year-3 ECG LVH and left ventricular midwall shortening (MWS) were examined in 725 hypertensive patients in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiographic...... 1.03-3.50, P = 0.040) at year 3. CONCLUSION: Persistence or development of new ECG LVH during antihypertensive therapy is associated with an increased risk of left ventricular systolic dysfunction after 3 years' follow-up. These findings provide insight into a possible mechanism by which changes......BACKGROUND: Persistence or development of ECG left ventricular hypertrophy (LVH) by Cornell product criteria is associated with an increased risk of developing heart failure compared with regression or continued absence of LVH. We postulated that this association might be in part mediated via worse...

A response matrix method for one-speed discrete ordinates fixed source problems in slab geometry with no spatial truncation error

International Nuclear Information System (INIS)

Lydia, Emilio J.; Barros, Ricardo C.

2011-01-01

In this paper we describe a response matrix method for one-speed slab-geometry discrete ordinates (SN) neutral particle transport problems that is completely free from spatial truncation errors. The unknowns in the method are the cell-edge angular fluxes of particles. The numerical results generated for these quantities are exactly those obtained from the analytic solution of the SN problem apart from finite arithmetic considerations. Our method is based on a spectral analysis that we perform in the SN equations with scattering inside a discretization cell of the spatial grid set up on the slab. As a result of this spectral analysis, we are able to obtain an expression for the local general solution of the SN equations. With this local general solution, we determine the response matrix and use the prescribed boundary conditions and continuity conditions to sweep across the discretization cells from left to right and from right to left across the slab, until a prescribed convergence criterion is satisfied. (author)

N-terminally truncated POM121C inhibits HIV-1 replication.

Directory of Open Access Journals (Sweden)

Hideki Saito

Full Text Available Recent studies have identified host cell factors that regulate early stages of HIV-1 infection including viral cDNA synthesis and orientation of the HIV-1 capsid (CA core toward the nuclear envelope, but it remains unclear how viral DNA is imported through the nuclear pore and guided to the host chromosomal DNA. Here, we demonstrate that N-terminally truncated POM121C, a component of the nuclear pore complex, blocks HIV-1 infection. This truncated protein is predominantly localized in the cytoplasm, does not bind to CA, does not affect viral cDNA synthesis, reduces the formation of 2-LTR and diminished the amount of integrated proviral DNA. Studies with an HIV-1-murine leukemia virus (MLV chimeric virus carrying the MLV-derived Gag revealed that Gag is a determinant of this inhibition. Intriguingly, mutational studies have revealed that the blockade by N-terminally-truncated POM121C is closely linked to its binding to importin-β/karyopherin subunit beta 1 (KPNB1. These results indicate that N-terminally-truncated POM121C inhibits HIV-1 infection after completion of reverse transcription and before integration, and suggest an important role for KPNB1 in HIV-1 replication.

Estimation of Panel Data Regression Models with Two-Sided Censoring or Truncation

DEFF Research Database (Denmark)

Alan, Sule; Honore, Bo E.; Hu, Luojia

2014-01-01

This paper constructs estimators for panel data regression models with individual speci…fic heterogeneity and two–sided censoring and truncation. Following Powell (1986) the estimation strategy is based on moment conditions constructed from re–censored or re–truncated residuals. While these moment...

A generalized right truncated bivariate Poisson regression model with applications to health data.

Science.gov (United States)

Islam, M Ataharul; Chowdhury, Rafiqul I

2017-01-01

A generalized right truncated bivariate Poisson regression model is proposed in this paper. Estimation and tests for goodness of fit and over or under dispersion are illustrated for both untruncated and right truncated bivariate Poisson regression models using marginal-conditional approach. Estimation and test procedures are illustrated for bivariate Poisson regression models with applications to Health and Retirement Study data on number of health conditions and the number of health care services utilized. The proposed test statistics are easy to compute and it is evident from the results that the models fit the data very well. A comparison between the right truncated and untruncated bivariate Poisson regression models using the test for nonnested models clearly shows that the truncated model performs significantly better than the untruncated model.

Bounded real and positive real balanced truncation using Σ-normalised coprime factors

NARCIS (Netherlands)

Trentelman, H.L.

2009-01-01

In this article, we will extend the method of balanced truncation using normalised right coprime factors of the system transfer matrix to balanced truncation with preservation of half line dissipativity. Special cases are preservation of positive realness and bounded realness. We consider a half

Reduction of variable-truncation artifacts from beam occlusion during in situ x-ray tomography

Science.gov (United States)

Borg, Leise; Jørgensen, Jakob S.; Frikel, Jürgen; Sporring, Jon

2017-12-01

Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance to sample is derived and verified numerically and with experimental data. The model accurately describes the arising variable-truncation artifacts across simulated variations of the experimental setup. Three variable-truncation artifact-reduction methods are proposed, all aimed at addressing sinogram discontinuities that are shown to be the source of the streaks. The ‘reduction to limited angle’ (RLA) method simply keeps only non-truncated projections; the ‘detector-directed smoothing’ (DDS) method smooths the discontinuities; while the ‘reflexive boundary condition’ (RBC) method enforces a zero derivative at the discontinuities. Experimental results using both simulated and real data show that the proposed methods effectively reduce variable-truncation artifacts. The RBC method is found to provide the best artifact reduction and preservation of image features using both visual and quantitative assessment. The analysis and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable-truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray tomography experiments.

Amplitude reconstruction from complete photoproduction experiments and truncated partial-wave expansions

International Nuclear Information System (INIS)

Workman, R. L.; Tiator, L.; Wunderlich, Y.; Doring, M.; Haberzettl, H.

2017-01-01

Here, we compare the methods of amplitude reconstruction, for a complete experiment and a truncated partial-wave analysis, applied to the photoproduction of pseudoscalar mesons. The approach is pedagogical, showing in detail how the amplitude reconstruction (observables measured at a single energy and angle) is related to a truncated partial-wave analysis (observables measured at a single energy and a number of angles).

Left atrial function to identify patients with atrial fibrillation at high risk of stroke: new insights from a large registry.

Science.gov (United States)

Leung, Melissa; van Rosendael, Philippe J; Abou, Rachid; Ajmone Marsan, Nina; Leung, Dominic Y; Delgado, Victoria; Bax, Jeroen J

2018-04-21

Atrial fibrillation (AF) is an independent risk factor for ischaemic stroke. The CHA2DS2-VASc is the most widely used risk stratification model; however, echocardiographic refinement may be useful, particularly in low risk AF patients. The present study examined the association between advanced echocardiographic parameters and ischaemic stroke, independent of CHA2DS2-VASc score. One thousand, three hundred and sixty-one patients (mean age 65±12 years, 74% males) with first diagnosis of AF and baseline transthoracic echocardiogram were followed by chart review for the occurrence of stroke over a mean of 7.9 years. Left atrial (LA) volumes, LA reservoir strain, P-wave to A' duration on tissue Doppler imaging (PA-TDI, reflecting total atrial conduction time), and left ventricular (LV) global longitudinal strain (GLS) were evaluated in patients with and without stroke. The independent association of these echocardiographic parameters with the occurrence of ischaemic stroke was evaluated with Cox proportional hazard models. One-hundred patients (7%) developed an ischaemic stroke, representing an annualized stroke rate of 0.9%. The incident stroke rate in the year following the first diagnosis of AF was 2.6% in the entire population and higher than the remainder of the follow-up period. Left atrial reservoir (14.5% vs. 18.9%, P = 0.005) and conduit strains were reduced (10.5% vs. 13.5%, P = 0.013), and PA-TDI lengthened (166 ms vs. 141 ms, P Left atrial reservoir strain and PA-TDI were independently associated with risk of stroke in a model including CHA2DS2-VASc score, age, and anticoagulant use. The assessment of LA reservoir strain and PA-TDI on echocardiography after initial CHA2DS2-VASc scoring provides additional risk stratification for stroke and may be useful to guide decisions regarding anticoagulation for patients upon first diagnosis of AF.

Modified Truncated Multiplicity Analysis to Improve Verification of Uranium Fuel Cycle Materials

International Nuclear Information System (INIS)

LaFleur, A.; Miller, K.; Swinhoe, M.; Belian, A.; Croft, S.

2015-01-01

Accurate verification of 235U enrichment and mass in UF6 storage cylinders and the UO2F2 holdup contained in the process equipment is needed to improve international safeguards and nuclear material accountancy at uranium enrichment plants. Small UF6 cylinders (1.5'' and 5'' diameter) are used to store the full range of enrichments from depleted to highly-enriched UF6. For independent verification of these materials, it is essential that the 235U mass and enrichment measurements do not rely on facility operator declarations. Furthermore, in order to be deployed by IAEA inspectors to detect undeclared activities (e.g., during complementary access), it is also imperative that the measurement technique is quick, portable, and sensitive to a broad range of 235U masses. Truncated multiplicity analysis is a technique that reduces the variance in the measured count rates by only considering moments 1, 2, and 3 of the multiplicity distribution. This is especially important for reducing the uncertainty in the measured doubles and triples rates in environments with a high cosmic ray background relative to the uranium signal strength. However, we believe that the existing truncated multiplicity analysis throws away too much useful data by truncating the distribution after the third moment. This paper describes a modified truncated multiplicity analysis method that determines the optimal moment to truncate the multiplicity distribution based on the measured data. Experimental measurements of small UF6 cylinders and UO2F2 working reference materials were performed at Los Alamos National Laboratory (LANL). The data were analyzed using traditional and modified truncated multiplicity analysis to determine the optimal moment to truncate the multiplicity distribution to minimize the uncertainty in the measured count rates. The results from this analysis directly support nuclear safeguards at enrichment plants and provide a more accurate verification method for UF6

Modeling the Effect of APC Truncation on Destruction Complex Function in Colorectal Cancer Cells

Science.gov (United States)

Barua, Dipak; Hlavacek, William S.

2013-01-01

In colorectal cancer cells, APC, a tumor suppressor protein, is commonly expressed in truncated form. Truncation of APC is believed to disrupt degradation of β—catenin, which is regulated by a multiprotein complex called the destruction complex. The destruction complex comprises APC, Axin, β—catenin, serine/threonine kinases, and other proteins. The kinases and , which are recruited by Axin, mediate phosphorylation of β—catenin, which initiates its ubiquitination and proteosomal degradation. The mechanism of regulation of β—catenin degradation by the destruction complex and the role of truncation of APC in colorectal cancer are not entirely understood. Through formulation and analysis of a rule-based computational model, we investigated the regulation of β—catenin phosphorylation and degradation by APC and the effect of APC truncation on function of the destruction complex. The model integrates available mechanistic knowledge about site-specific interactions and phosphorylation of destruction complex components and is consistent with an array of published data. We find that the phosphorylated truncated form of APC can outcompete Axin for binding to β—catenin, provided that Axin is limiting, and thereby sequester β—catenin away from Axin and the Axin-recruited kinases and . Full-length APC also competes with Axin for binding to β—catenin; however, full-length APC is able, through its SAMP repeats, which bind Axin and which are missing in truncated oncogenic forms of APC, to bring β—catenin into indirect association with Axin and Axin-recruited kinases. Because our model indicates that the positive effects of truncated APC on β—catenin levels depend on phosphorylation of APC, at the first 20-amino acid repeat, and because phosphorylation of this site is mediated by , we suggest that is a potential target for therapeutic intervention in colorectal cancer. Specific inhibition of is predicted to limit binding of β—catenin to truncated

A Lynden-Bell integral estimator for the tail index of right-truncated ...

African Journals Online (AJOL)

By means of a Lynden-Bell integral with deterministic threshold, Worms and Worms [A Lynden-Bell integral estimator for extremes of randomly truncated data. Statist. Probab. Lett. 2016; 109: 106-117] recently introduced an asymptotically normal estimator of the tail index for randomly right-truncated Pareto-type data.

Truncated States Obtained by Iteration

International Nuclear Information System (INIS)

Cardoso, W. B.; Almeida, N. G. de

2008-01-01

We introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST

The Dynamics of Truncated Black Hole Accretion Disks. I. Viscous Hydrodynamic Case

Energy Technology Data Exchange (ETDEWEB)

Hogg, J. Drew; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)

2017-07-10

Truncated accretion disks are commonly invoked to explain the spectro-temporal variability in accreting black holes in both small systems, i.e., state transitions in galactic black hole binaries (GBHBs), and large systems, i.e., low-luminosity active galactic nuclei (LLAGNs). In the canonical truncated disk model of moderately low accretion rate systems, gas in the inner region of the accretion disk occupies a hot, radiatively inefficient phase, which leads to a geometrically thick disk, while the gas in the outer region occupies a cooler, radiatively efficient phase that resides in the standard geometrically thin disk. Observationally, there is strong empirical evidence to support this phenomenological model, but a detailed understanding of the dynamics of truncated disks is lacking. We present a well-resolved viscous, hydrodynamic simulation that uses an ad hoc cooling prescription to drive a thermal instability and, hence, produce the first sustained truncated accretion disk. With this simulation, we perform a study of the dynamics, angular momentum transport, and energetics of a truncated disk. We find that the time variability introduced by the quasi-periodic transition of gas from efficient cooling to inefficient cooling impacts the evolution of the simulated disk. A consequence of the thermal instability is that an outflow is launched from the hot/cold gas interface, which drives large, sub-Keplerian convective cells into the disk atmosphere. The convective cells introduce a viscous θ − ϕ stress that is less than the generic r − ϕ viscous stress component, but greatly influences the evolution of the disk. In the truncated disk, we find that the bulk of the accreted gas is in the hot phase.

A Multistep Extending Truncation Method towards Model Construction of Infinite-State Markov Chains

Directory of Open Access Journals (Sweden)

Kemin Wang

2014-01-01

Full Text Available The model checking of Infinite-State Continuous Time Markov Chains will inevitably encounter the state explosion problem when constructing the CTMCs model; our method is to get a truncated model of the infinite one; to get a sufficient truncated model to meet the model checking of Continuous Stochastic Logic based system properties, we propose a multistep extending advanced truncation method towards model construction of CTMCs and implement it in the INFAMY model checker; the experiment results show that our method is effective.

Can we reduce the risk of disease heart in treatments of left breast? bated breath

International Nuclear Information System (INIS)

Fuentemilla Urio, N.; Lozares Cordero, S.; Otal Palacin, A.; Olasolo Alonso, J.; Pellejero Pellejero, S.; Martin Albina, M. L.; Maneru Camara, F.; Miquelez Alonso, S.; Rubio Arroniz, T.; Soto Prados, P.

2013-01-01

In studies related to breast cancer and mortality, there has been an increase in the mortality of patients with survival greater than 10 years treated with radiotherapy. Subsequent studies it appears that the main cause is heart disease. Therefore, that the heart started to consider organ of risk in the treatment of breast cancer with radiation therapy (adjuvant). Reducing the doses both heart and coronary arteries leads to a reduction in the risk of heart disease. Currently are introducing new techniques, to reduce the dose in heart and in the left anterior descending coronary artery such as new positions or techniques of Breath bated breath hold... (Author)

Molecular dynamics simulations of lipid bilayers : major artifacts due to truncating electrostatic interactions

NARCIS (Netherlands)

Patra, M.; Karttunen, M.E.J.; Hyvönen, M.T.; Falck, E.; Lindqvist, P.; Vattulainen, I.

2003-01-01

We study the influence of truncating the electrostatic interactions in a fully hydrated pure dipalmitoylphosphatidylcholine (DPPC) bilayer through 20 ns molecular dynamics simulations. The computations in which the electrostatic interactions were truncated are compared to similar simulations using

Clinical Characteristics and Risk Factors of Left Ventricular Thrombus after Acute Myocardial Infarction: A Matched Case-control Study

Directory of Open Access Journals (Sweden)

Yue-Xin Jiang

2015-01-01

Conclusions: This study indicated that lower LVEF, extensive anterior myocardial infarction, severe RWMA, and left ventricular aneurysm were independent risk factors of LVT after AMI. It also suggested that further efforts are needed for the LVT diagnosis after AMI in clinical practice.

On the viability of the truncated Israel–Stewart theory in cosmology

International Nuclear Information System (INIS)

Shogin, Dmitry; Amundsen, Per Amund; Hervik, Sigbjørn

2015-01-01

We apply the causal Israel–Stewart theory of irreversible thermodynamics to model the matter content of the Universe as a dissipative fluid with bulk and shear viscosity. Along with the full transport equations we consider their widely used truncated version. By implementing a dynamical systems approach to Bianchi type IV and V cosmological models with and without cosmological constant, we determine the future asymptotic states of such Universes and show that the truncated Israel–Stewart theory leads to solutions essentially different from the full theory. The solutions of the truncated theory may also manifest unphysical properties. Finally, we find that in the full theory shear viscosity can give a substantial rise to dissipative fluxes, driving the fluid extremely far from equilibrium, where the linear Israel–Stewart theory ceases to be valid. (paper)

Autoantibodies to N-terminally truncated GAD improve clinical phenotyping of individuals with adult-onset diabetes: Action LADA 12.

Science.gov (United States)

Achenbach, Peter; Hawa, Mohammed I; Krause, Stephanie; Lampasona, Vito; Jerram, Samuel T; Williams, Alistair J K; Bonifacio, Ezio; Ziegler, Anette G; Leslie, R David

2018-04-04

Adult-onset type 1 diabetes, in which the 65 kDa isoform of GAD (GAD65) is a major autoantigen, has a broad clinical phenotype encompassing variable need for insulin therapy. This study aimed to evaluate whether autoantibodies against N-terminally truncated GAD65 more closely defined a type 1 diabetes phenotype associated with insulin therapy. Of 1114 participants with adult-onset diabetes from the Action LADA (latent autoimmune diabetes in adults) study with sufficient sera, we selected those designated type 1 (n = 511) or type 2 diabetes (n = 603) and retested the samples in radiobinding assays for human full-length GAD65 autoantibodies (f-GADA) and N-terminally truncated (amino acids 96-585) GAD65 autoantibodies (t-GADA). Individuals' clinical phenotypes were analysed according to antibody binding patterns. Overall, 478 individuals were f-GADA-positive, 431 were t-GADA-positive and 628 were negative in both assays. Risk of insulin treatment was augmented in t-GADA-positive individuals (OR 4.69 [95% CI 3.57, 6.17]) compared with f-GADA-positive individuals (OR 3.86 [95% CI 2.95, 5.06]), irrespective of diabetes duration. Of 55 individuals who were f-GADA-positive but t-GADA-negative, i.e. with antibody binding restricted to the N-terminus of GAD65, the phenotype was similar to type 2 diabetes with low risk of progression to insulin treatment. Compared with these individuals with N-terminal GAD65-restricted GADA, t-GADA-positive individuals were younger at diagnosis (p = 0.005), leaner (p N-terminally truncated GAD65 autoantibodies is associated with the clinical phenotype of autoimmune type 1 diabetes and predicts insulin therapy.

Left main coronary artery disease: pathophysiology, diagnosis, and treatment.

Science.gov (United States)

Collet, Carlos; Capodanno, Davide; Onuma, Yoshinobu; Banning, Adrian; Stone, Gregg W; Taggart, David P; Sabik, Joseph; Serruys, Patrick W

2018-06-01

The advent of coronary angiography in the 1960s allowed for the risk stratification of patients with stable angina. Patients with unprotected left main coronary artery disease have an increased risk of death related to the large amount of myocardium supplied by this vessel. Although coronary angiography remains the preferred imaging modality for the evaluation of left main coronary artery stenosis, this technique has important limitations. Angiograms of the left main coronary artery segment can be difficult to interpret, and almost one-third of patients can be misclassified when fractional flow reserve is used as the reference. In patients with clinically significant unprotected left main coronary artery disease, surgical revascularization was shown to improve survival compared with medical therapy and has been regarded as the treatment of choice for unprotected left main coronary artery disease. Two large-scale clinical trials published in 2016 support the usefulness of catheter-based revascularization in selected patients with unprotected left main coronary artery disease. In this Review, we describe the pathophysiology of unprotected left main coronary artery disease, discuss diagnostic approaches in light of new noninvasive and invasive imaging techniques, and detail risk stratification models to aid the Heart Team in the decision-making process for determining the best revascularization strategy for these patients.

Riesz Representation Theorem on Bilinear Spaces of Truncated Laurent Series

Directory of Open Access Journals (Sweden)

Sabarinsyah

2017-06-01

Full Text Available In this study a generalization of the Riesz representation theorem on non-degenerate bilinear spaces, particularly on spaces of truncated Laurent series, was developed. It was shown that any linear functional on a non-degenerate bilinear space is representable by a unique element of the space if and only if its kernel is closed. Moreover an explicit equivalent condition can be identified for the closedness property of the kernel when the bilinear space is a space of truncated Laurent series.

Pressure-sensitive paint on a truncated cone in hypersonic flow at incidences

International Nuclear Information System (INIS)

Yang, L.; Erdem, E.; Zare-Behtash, H.; Kontis, K.; Saravanan, S.

2012-01-01

Highlights: ► Global pressure map over the truncated cone is obtained at various incidence angles in Mach 5 flow. ► Successful application of AA-PSP in hypersonic flow expands operation area of this technique. ► AA-PSP reveals complex three-dimensional pattern which is difficult for transducer to obtain. ► Quantitative data provides strong correlation with colour Schlieren and oil flow results. ► High spatial resolution pressure mappings identify small scale vortices and flow separation. - Abstract: The flow over a truncated cone is a classical and fundamental problem for aerodynamic research due to its three-dimensional and complicated characteristics. The flow is made more complex when examining high angles of incidence. Recently these types of flows have drawn more attention for the purposes of drag reduction in supersonic/hypersonic flows. In the present study the flow over a truncated cone at various incidences was experimentally investigated in a Mach 5 flow with a unit Reynolds number of 13.5 × 10 6 m −1 . The cone semi-apex angle is 15° and the truncation ratio (truncated length/cone length) is 0.5. The incidence of the model varied from −12° to 12° with 3° intervals relative to the freestream direction. The external flow around the truncated cone was visualised by colour Schlieren photography, while the surface flow pattern was revealed using the oil flow method. The surface pressure distribution was measured using the anodized aluminium pressure-sensitive paint (AA-PSP) technique. Both top and sideviews of the pressure distribution on the model surface were acquired at various incidences. AA-PSP showed high pressure sensitivity and captured the complicated flow structures which correlated well with the colour Schlieren and oil flow visualisation results.

High baseline left ventricular and systolic volume may identify patients at risk of chemotherapy-induced cardiotoxicity

International Nuclear Information System (INIS)

Atiar Rahman; Alex Gedevanishvili; Seham Ali; Elma G Briscoe; Vani Vijaykumar

2004-01-01

Introduction and Methods: Use of chemotherapeutic drugs in the treatment of cancer may lead to serious cardiotoxicity and to post-treatment heart failure. Various strategies have been developed to minimize the risk of cardiotoxicity including avoiding the total dosage given to each patient above a certain 'threshold' value; and monitoring the patient's cardiac function by means of the 'Multiple Gated Acquisition' (MUGA) scan using Technetium 99m . However, even with all these precautions some patients still develop cardiotoxicity and it is not well known which factors predict deterioration of cardiac functions in patients with optimized chemotherapeutic dosages. In this retrospective study we sought to evaluate the predictive value of seven variables (age, sex, baseline LV ejection fraction, LV end diastolic [LDEDV] and end systolic volumes [LVESV], peak diastolic filling rate, preexisting malignancies requiring chemotherapy) in 172 patients (n=Breast Carcinoma 86, lymphoma 62, Leukemias and others 24) undergoing chemotherapy from 1995 until 2000. There was no cut off for left ventricular ejection fraction prior to chemotherapy. However, patients were excluded from analysis if they had significant cardiac arrhythmias or received doses higher than considered safe for cardiotoxicity at the beginning of the study. Significant cardiotoxicity was defined as a drop in post chemotherapy LVEF by >15%. Results: Logistic regression models were used to predict the probability of developing cardiotoxicity as a function of the seven prognostic covariates. The mean age of all patients was 51+13 years. Significant Cardiac toxicity was noted in 10 percent of patients. The overall risk estimate for subsequent heart failure after chemotherapy, however, climbed to 18 percent in patients with a presenting LVESD >50 mL. Using multivariate logistic regression model, older age was noted to be a weak risk factors for cardiac toxicity (confidence interval 0.8-1.2; p 50 mL) appeared to

On truncations of the exact renormalization group

CERN Document Server

Morris, T R

1994-01-01

We investigate the Exact Renormalization Group (ERG) description of (Z_2 invariant) one-component scalar field theory, in the approximation in which all momentum dependence is discarded in the effective vertices. In this context we show how one can perform a systematic search for non-perturbative continuum limits without making any assumption about the form of the lagrangian. Concentrating on the non-perturbative three dimensional Wilson fixed point, we then show that the sequence of truncations n=2,3,\\dots, obtained by expanding about the field \\varphi=0 and discarding all powers \\varphi^{2n+2} and higher, yields solutions that at first converge to the answer obtained without truncation, but then cease to further converge beyond a certain point. No completely reliable method exists to reject the many spurious solutions that are also found. These properties are explained in terms of the analytic behaviour of the untruncated solutions -- which we describe in some detail.

Resonant Excitation of a Truncated Metamaterial Cylindrical Shell by a Thin Wire Monopole

DEFF Research Database (Denmark)

Kim, Oleksiy S.; Erentok, Aycan; Breinbjerg, Olav

2009-01-01

A truncated metamaterial cylindrical shell excited by a thin wire monopole is investigated using the integral equation technique as well as the finite element method. Simulations reveal a strong field singularity at the edge of the truncated cylindrical shell, which critically affects the matching...

Squeezing in multi-mode nonlinear optical state truncation

International Nuclear Information System (INIS)

Said, R.S.; Wahiddin, M.R.B.; Umarov, B.A.

2007-01-01

In this Letter, we show that multi-mode qubit states produced via nonlinear optical state truncation driven by classical external pumpings exhibit squeezing condition. We restrict our discussions to the two- and three-mode cases

Multiple imputation for estimating the risk of developing dementia and its impact on survival.

Science.gov (United States)

Yu, Binbing; Saczynski, Jane S; Launer, Lenore

2010-10-01

Dementia, Alzheimer's disease in particular, is one of the major causes of disability and decreased quality of life among the elderly and a leading obstacle to successful aging. Given the profound impact on public health, much research has focused on the age-specific risk of developing dementia and the impact on survival. Early work has discussed various methods of estimating age-specific incidence of dementia, among which the illness-death model is popular for modeling disease progression. In this article we use multiple imputation to fit multi-state models for survival data with interval censoring and left truncation. This approach allows semi-Markov models in which survival after dementia depends on onset age. Such models can be used to estimate the cumulative risk of developing dementia in the presence of the competing risk of dementia-free death. Simulations are carried out to examine the performance of the proposed method. Data from the Honolulu Asia Aging Study are analyzed to estimate the age-specific and cumulative risks of dementia and to examine the effect of major risk factors on dementia onset and death.

Motion of isolated open vortex filaments evolving under the truncated local induction approximation

Science.gov (United States)

Van Gorder, Robert A.

2017-11-01

The study of nonlinear waves along open vortex filaments continues to be an area of active research. While the local induction approximation (LIA) is attractive due to locality compared with the non-local Biot-Savart formulation, it has been argued that LIA appears too simple to model some relevant features of Kelvin wave dynamics, such as Kelvin wave energy transfer. Such transfer of energy is not feasible under the LIA due to integrability, so in order to obtain a non-integrable model, a truncated LIA, which breaks the integrability of the classical LIA, has been proposed as a candidate model with which to study such dynamics. Recently Laurie et al. ["Interaction of Kelvin waves and nonlocality of energy transfer in superfluids," Phys. Rev. B 81, 104526 (2010)] derived truncated LIA systematically from Biot-Savart dynamics. The focus of the present paper is to study the dynamics of a section of common open vortex filaments under the truncated LIA dynamics. We obtain the analog of helical, planar, and more general filaments which rotate without a change in form in the classical LIA, demonstrating that while quantitative differences do exist, qualitatively such solutions still exist under the truncated LIA. Conversely, solitons and breather solutions found under the LIA should not be expected under the truncated LIA, as the existence of such solutions relies on the existence of an infinite number of conservation laws which is violated due to loss of integrability. On the other hand, similarity solutions under the truncated LIA can be quite different to their counterparts found for the classical LIA, as they must obey a t1/3 type scaling rather than the t1/2 type scaling commonly found in the LIA and Biot-Savart dynamics. This change in similarity scaling means that Kelvin waves are radiated at a slower rate from vortex kinks formed after reconnection events. The loss of soliton solutions and the difference in similarity scaling indicate that dynamics emergent under

The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

Science.gov (United States)

Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

2014-02-01

Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

UFO in the Left Atrium: How to Capture Metal Debris Floating in the Left Atrium.

Science.gov (United States)

Fassini, Gaetano; Moltrasio, Massimo; Conti, Sergio; Biagioli, Viviana; Tondo, Claudio

2016-06-01

Electrophysiology procedures involving left atrium navigation are becoming more frequent, mostly due to the increase of atrial fibrillation ablation. Mapping catheters of different shapes and size as well as dedicated sheaths are mandatory tools for the accomplishment of procedural end point. Therefore, technical issues are expected, usually unrelated to significant risk. However, any accidental intra-atrial device loss of integrity implies a risk of cerebrovascular embolization. The lack of clear evidence on how to manage these events and the need for a quick solution complicate the scenario. We report an empirical solution in the case of debris floating in the left atrium. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Local and accumulated truncation errors in a class of perturbative numerical methods

International Nuclear Information System (INIS)

Adam, G.; Adam, S.; Corciovei, A.

1980-01-01

The approach to the solution of the radial Schroedinger equation using piecewise perturbative theory with a step function reference potential leads to a class of powerful numerical methods, conveniently abridged as SF-PNM(K), where K denotes the order at which the perturbation series was truncated. In the present paper rigorous results are given for the local truncation errors and bounds are derived for the accumulated truncated errors associated to SF-PNM(K), K = 0, 1, 2. They allow us to establish the smoothness conditions which have to be fulfilled by the potential in order to ensure a safe use of SF-PNM(K), and to understand the experimentally observed behaviour of the numerical results with the step size h. (author)

Frequency interval balanced truncation of discrete-time bilinear systems

DEFF Research Database (Denmark)

Jazlan, Ahmad; Sreeram, Victor; Shaker, Hamid Reza

2016-01-01

This paper presents the development of a new model reduction method for discrete-time bilinear systems based on the balanced truncation framework. In many model reduction applications, it is advantageous to analyze the characteristics of the system with emphasis on particular frequency intervals...... are the solution to a pair of new generalized Lyapunov equations. The conditions for solvability of these new generalized Lyapunov equations are derived and a numerical solution method for solving these generalized Lyapunov equations is presented. Numerical examples which illustrate the usage of the new...... generalized frequency interval controllability and observability gramians as part of the balanced truncation framework are provided to demonstrate the performance of the proposed method....

Adaptive bit plane quadtree-based block truncation coding for image compression

Science.gov (United States)

Li, Shenda; Wang, Jin; Zhu, Qing

2018-04-01

Block truncation coding (BTC) is a fast image compression technique applied in spatial domain. Traditional BTC and its variants mainly focus on reducing computational complexity for low bit rate compression, at the cost of lower quality of decoded images, especially for images with rich texture. To solve this problem, in this paper, a quadtree-based block truncation coding algorithm combined with adaptive bit plane transmission is proposed. First, the direction of edge in each block is detected using Sobel operator. For the block with minimal size, adaptive bit plane is utilized to optimize the BTC, which depends on its MSE loss encoded by absolute moment block truncation coding (AMBTC). Extensive experimental results show that our method gains 0.85 dB PSNR on average compare to some other state-of-the-art BTC variants. So it is desirable for real time image compression applications.

Usefulness of left ventricular wall thickness-to-diameter ratio in thallium-201 scintigraphy

International Nuclear Information System (INIS)

Manno, B.; Hakki, A.H.; Kane, S.A.; Iskandrian, A.S.

1983-01-01

The ratio of left ventricular wall thickness to the cavity dimension, as seen on thallium-201 images, was used in this study to predict left ventricular ejection fraction and volume. We obtained rest thallium-201 images in 50 patients with symptomatic coronary artery disease. The thickness of a normal-appearing segment of the left ventricular wall and the transverse diameter of the cavity were measured in the left anterior oblique projection. The left ventricular ejection fraction and volume in these patients were determined by radionuclide ventriculography. There was a good correlation between thickness-to-diameter ratio and ejection fraction and end-systolic volume. In 18 patients with a thickness-to-diameter ratio less than 0.70, the ejection fraction was lower than in the 16 patients with thickness-to-diameter ratio greater than or equal to 1.0. Similarly, in patients with a thickness-to-diameter ratio less than 0.70, the end-diastolic and end-systolic volume were higher than in the remaining patients with higher thickness-to-diameter ratios. All 18 patients with a thickness-to-diameter ratio less than 0.70 had ejection fractions less than 40%; 14 of 15 patients with a thickness-to-diameter ratio greater than or equal to 1.0 had an ejection fraction greater than 40%. The remaining 16 patients with a thickness-to-diameter ratio of 0.7-0.99 had intermediate ejection fractions and volumes.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence for Truncated Exponential Probability Distribution of Earthquake Slip

KAUST Repository

Thingbaijam, Kiran Kumar; Mai, Paul Martin

2016-01-01

Earthquake ruptures comprise spatially varying slip on the fault surface, where slip represents the displacement discontinuity between the two sides of the rupture plane. In this study, we analyze the probability distribution of coseismic slip, which provides important information to better understand earthquake source physics. Although the probability distribution of slip is crucial for generating realistic rupture scenarios for simulation-based seismic and tsunami-hazard analysis, the statistical properties of earthquake slip have received limited attention so far. Here, we use the online database of earthquake source models (SRCMOD) to show that the probability distribution of slip follows the truncated exponential law. This law agrees with rupture-specific physical constraints limiting the maximum possible slip on the fault, similar to physical constraints on maximum earthquake magnitudes.We show the parameters of the best-fitting truncated exponential distribution scale with average coseismic slip. This scaling property reflects the control of the underlying stress distribution and fault strength on the rupture dimensions, which determines the average slip. Thus, the scale-dependent behavior of slip heterogeneity is captured by the probability distribution of slip. We conclude that the truncated exponential law accurately quantifies coseismic slip distribution and therefore allows for more realistic modeling of rupture scenarios. © 2016, Seismological Society of America. All rights reserverd.

Evidence for Truncated Exponential Probability Distribution of Earthquake Slip

KAUST Repository

Thingbaijam, Kiran K. S.

2016-07-13

Earthquake ruptures comprise spatially varying slip on the fault surface, where slip represents the displacement discontinuity between the two sides of the rupture plane. In this study, we analyze the probability distribution of coseismic slip, which provides important information to better understand earthquake source physics. Although the probability distribution of slip is crucial for generating realistic rupture scenarios for simulation-based seismic and tsunami-hazard analysis, the statistical properties of earthquake slip have received limited attention so far. Here, we use the online database of earthquake source models (SRCMOD) to show that the probability distribution of slip follows the truncated exponential law. This law agrees with rupture-specific physical constraints limiting the maximum possible slip on the fault, similar to physical constraints on maximum earthquake magnitudes.We show the parameters of the best-fitting truncated exponential distribution scale with average coseismic slip. This scaling property reflects the control of the underlying stress distribution and fault strength on the rupture dimensions, which determines the average slip. Thus, the scale-dependent behavior of slip heterogeneity is captured by the probability distribution of slip. We conclude that the truncated exponential law accurately quantifies coseismic slip distribution and therefore allows for more realistic modeling of rupture scenarios. © 2016, Seismological Society of America. All rights reserverd.

High-yield water-based synthesis of truncated silver nanocubes

International Nuclear Information System (INIS)

Chang, Yun-Min; Lu, I-Te; Chen, Chih-Yuan; Hsieh, Yu-Chi; Wu, Pu-Wei

2014-01-01

Highlights: • Development of a water-based formula to fabricate truncated Ag nanocubes. • The sample exhibits (1 0 0), (1 1 0), and (1 1 1) on the facets, edges, and corners. • The sample shows three characteristic absorption peaks due to plasma resonance. -- Abstract: A high-yield water-based hydrothermal synthesis was developed using silver nitrate, ammonia, glucose, and cetyltrimethylammonium bromide (CTAB) as precursors to synthesize truncated silver nanocubes with uniform sizes and in large quantities. With a fixed CTAB concentration, truncated silver nanocubes with sizes of 49.3 ± 4.1 nm were produced when the molar ratio of glucose/silver cation was maintained at 0.1. The sample exhibited (1 0 0), (1 1 0), and (1 1 1) planes on the facets, edges, and corners, respectively. In contrast, with a slightly larger glucose/silver cation ratio of 0.35, well-defined nanocubes with sizes of 70.9 ± 3.8 nm sizes were observed with the (1 0 0) plane on six facets. When the ratio was further increased to 1.5, excess reduction of silver cations facilitated the simultaneous formation of nanoparticles with cubic, spherical, and irregular shapes. Consistent results were obtained from transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and UV–visible absorption measurements

High-yield water-based synthesis of truncated silver nanocubes

Energy Technology Data Exchange (ETDEWEB)

Chang, Yun-Min; Lu, I-Te; Chen, Chih-Yuan; Hsieh, Yu-Chi; Wu, Pu-Wei, E-mail: ppwu@mail.nctu.edu.tw

2014-02-15

Highlights: • Development of a water-based formula to fabricate truncated Ag nanocubes. • The sample exhibits (1 0 0), (1 1 0), and (1 1 1) on the facets, edges, and corners. • The sample shows three characteristic absorption peaks due to plasma resonance. -- Abstract: A high-yield water-based hydrothermal synthesis was developed using silver nitrate, ammonia, glucose, and cetyltrimethylammonium bromide (CTAB) as precursors to synthesize truncated silver nanocubes with uniform sizes and in large quantities. With a fixed CTAB concentration, truncated silver nanocubes with sizes of 49.3 ± 4.1 nm were produced when the molar ratio of glucose/silver cation was maintained at 0.1. The sample exhibited (1 0 0), (1 1 0), and (1 1 1) planes on the facets, edges, and corners, respectively. In contrast, with a slightly larger glucose/silver cation ratio of 0.35, well-defined nanocubes with sizes of 70.9 ± 3.8 nm sizes were observed with the (1 0 0) plane on six facets. When the ratio was further increased to 1.5, excess reduction of silver cations facilitated the simultaneous formation of nanoparticles with cubic, spherical, and irregular shapes. Consistent results were obtained from transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and UV–visible absorption measurements.

Intersection spaces, spatial homology truncation, and string theory

CERN Document Server

Banagl, Markus

2010-01-01

Intersection cohomology assigns groups which satisfy a generalized form of Poincaré duality over the rationals to a stratified singular space. The present monograph introduces a method that assigns to certain classes of stratified spaces cell complexes, called intersection spaces, whose ordinary rational homology satisfies generalized Poincaré duality. The cornerstone of the method is a process of spatial homology truncation, whose functoriality properties are analyzed in detail. The material on truncation is autonomous and may be of independent interest to homotopy theorists. The cohomology of intersection spaces is not isomorphic to intersection cohomology and possesses algebraic features such as perversity-internal cup-products and cohomology operations that are not generally available for intersection cohomology. A mirror-symmetric interpretation, as well as applications to string theory concerning massless D-branes arising in type IIB theory during a Calabi-Yau conifold transition, are discussed.

The Apparent Lack of Lorentz Invariance in Zero-Point Fields with Truncated Spectra

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Daywitt W. C.

2009-01-01

Full Text Available The integrals that describe the expectation values of the zero-point quantum-field-theoretic vacuum state are semi-infinite, as are the integrals for the stochastic electrodynamic vacuum. The unbounded upper limit to these integrals leads in turn to infinite energy densities and renormalization masses. A number of models have been put forward to truncate the integrals so that these densities and masses are finite. Unfortunately the truncation apparently destroys the Lorentz invariance of the integrals. This note argues that the integrals are naturally truncated by the graininess of the negative-energy Planck vacuum state from which the zero-point vacuum arises, and are thus automatically Lorentz invariant.

Effectiveness of screening colonoscopy in reducing the risk of death from right and left colon cancer: a large community-based study.

Science.gov (United States)

Doubeni, Chyke A; Corley, Douglas A; Quinn, Virginia P; Jensen, Christopher D; Zauber, Ann G; Goodman, Michael; Johnson, Jill R; Mehta, Shivan J; Becerra, Tracy A; Zhao, Wei K; Schottinger, Joanne; Doria-Rose, V Paul; Levin, Theodore R; Weiss, Noel S; Fletcher, Robert H

2018-02-01

Screening colonoscopy's effectiveness in reducing colorectal cancer mortality risk in community populations is unclear, particularly for right-colon cancers, leading to recommendations against its use for screening in some countries. This study aimed to determine whether, among average-risk people, receipt of screening colonoscopy reduces the risk of dying from both right-colon and left-colon/rectal cancers. We conducted a nested case-control study with incidence-density matching in screening-eligible Kaiser Permanente members. Patients who were 55-90 years old on their colorectal cancer death date during 2006-2012 were matched on diagnosis (reference) date to controls on age, sex, health plan enrolment duration and geographical region. We excluded patients at increased colorectal cancer risk, or with prior colorectal cancer diagnosis or colectomy. The association between screening colonoscopy receipt in the 10-year period before the reference date and colorectal cancer death risk was evaluated while accounting for other screening exposures. We analysed 1747 patients who died from colorectal cancer and 3460 colorectal cancer-free controls. Compared with no endoscopic screening, receipt of a screening colonoscopy was associated with a 67% reduction in the risk of death from any colorectal cancer (adjusted OR (aOR)=0.33, 95% CI 0.21 to 0.52). By cancer location, screening colonoscopy was associated with a 65% reduction in risk of death for right-colon cancers (aOR=0.35, CI 0.18 to 0.65) and a 75% reduction for left-colon/rectal cancers (aOR=0.25, CI 0.12 to 0.53). Screening colonoscopy was associated with a substantial and comparably decreased mortality risk for both right-sided and left-sided cancers within a large community-based population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Reduction of variable-truncation artifacts from beam occlusion during in situ x-ray tomography

DEFF Research Database (Denmark)

Borg, Leise; Jørgensen, Jakob Sauer; Frikel, Jürgen

2017-01-01

Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered...... and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable-truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray...... backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance...

Propagation of a general-type beam through a truncated fractional Fourier transform optical system.

Science.gov (United States)

Zhao, Chengliang; Cai, Yangjian

2010-03-01

Paraxial propagation of a general-type beam through a truncated fractional Fourier transform (FRT) optical system is investigated. Analytical formulas for the electric field and effective beam width of a general-type beam in the FRT plane are derived based on the Collins formula. Our formulas can be used to study the propagation of a variety of laser beams--such as Gaussian, cos-Gaussian, cosh-Gaussian, sine-Gaussian, sinh-Gaussian, flat-topped, Hermite-cosh-Gaussian, Hermite-sine-Gaussian, higher-order annular Gaussian, Hermite-sinh-Gaussian and Hermite-cos-Gaussian beams--through a FRT optical system with or without truncation. The propagation properties of a Hermite-cos-Gaussian beam passing through a rectangularly truncated FRT optical system are studied as a numerical example. Our results clearly show that the truncated FRT optical system provides a convenient way for laser beam shaping.

Model-based approach for quantitative estimates of skin, heart, and lung toxicity risk for left-side photon and proton irradiation after breast-conserving surgery.

Science.gov (United States)

Tommasino, Francesco; Durante, Marco; D'Avino, Vittoria; Liuzzi, Raffaele; Conson, Manuel; Farace, Paolo; Palma, Giuseppe; Schwarz, Marco; Cella, Laura; Pacelli, Roberto

2017-05-01

Proton beam therapy represents a promising modality for left-side breast cancer (BC) treatment, but concerns have been raised about skin toxicity and poor cosmesis. The aim of this study is to apply skin normal tissue complication probability (NTCP) model for intensity modulated proton therapy (IMPT) optimization in left-side BC. Ten left-side BC patients undergoing photon irradiation after breast-conserving surgery were randomly selected from our clinical database. Intensity modulated photon (IMRT) and IMPT plans were calculated with iso-tumor-coverage criteria and according to RTOG 1005 guidelines. Proton plans were computed with and without skin optimization. Published NTCP models were employed to estimate the risk of different toxicity endpoints for skin, lung, heart and its substructures. Acute skin NTCP evaluation suggests a lower toxicity level with IMPT compared to IMRT when the skin is included in proton optimization strategy (0.1% versus 1.7%, p < 0.001). Dosimetric results show that, with the same level of tumor coverage, IMPT attains significant heart and lung dose sparing compared with IMRT. By NTCP model-based analysis, an overall reduction in the cardiopulmonary toxicity risk prediction can be observed for all IMPT compared to IMRT plans: the relative risk reduction from protons varies between 0.1 and 0.7 depending on the considered toxicity endpoint. Our analysis suggests that IMPT might be safely applied without increasing the risk of severe acute radiation induced skin toxicity. The quantitative risk estimates also support the potential clinical benefits of IMPT for left-side BC irradiation due to lower risk of cardiac and pulmonary morbidity. The applied approach might be relevant on the long term for the setup of cost-effectiveness evaluation strategies based on NTCP predictions.

Functional analysis of Rift Valley fever virus NSs encoding a partial truncation.

Science.gov (United States)

Head, Jennifer A; Kalveram, Birte; Ikegami, Tetsuro

2012-01-01

Rift Valley fever virus (RVFV), belongs to genus Phlebovirus of the family Bunyaviridae, causes high rates of abortion and fetal malformation in infected ruminants as well as causing neurological disorders, blindness, or lethal hemorrhagic fever in humans. RVFV is classified as a category A priority pathogen and a select agent in the U.S., and currently there are no therapeutics available for RVF patients. NSs protein, a major virulence factor of RVFV, inhibits host transcription including interferon (IFN)-β mRNA synthesis and promotes degradation of dsRNA-dependent protein kinase (PKR). NSs self-associates at the C-terminus 17 aa., while NSs at aa.210-230 binds to Sin3A-associated protein (SAP30) to inhibit the activation of IFN-β promoter. Thus, we hypothesize that NSs function(s) can be abolished by truncation of specific domains, and co-expression of nonfunctional NSs with intact NSs will result in the attenuation of NSs function by dominant-negative effect. Unexpectedly, we found that RVFV NSs truncated at aa. 6-30, 31-55, 56-80, 81-105, 106-130, 131-155, 156-180, 181-205, 206-230, 231-248 or 249-265 lack functions of IFN-β mRNA synthesis inhibition and degradation of PKR. Truncated NSs were less stable in infected cells, while nuclear localization was inhibited in NSs lacking either of aa.81-105, 106-130, 131-155, 156-180, 181-205, 206-230 or 231-248. Furthermore, none of truncated NSs had exhibited significant dominant-negative functions for NSs-mediated IFN-β suppression or PKR degradation upon co-expression in cells infected with RVFV. We also found that any of truncated NSs except for intact NSs does not interact with RVFV NSs even in the presence of intact C-terminus self-association domain. Our results suggest that conformational integrity of NSs is important for the stability, cellular localization and biological functions of RVFV NSs, and the co-expression of truncated NSs does not exhibit dominant-negative phenotype.

Functional analysis of Rift Valley fever virus NSs encoding a partial truncation.

Directory of Open Access Journals (Sweden)

Jennifer A Head

Full Text Available Rift Valley fever virus (RVFV, belongs to genus Phlebovirus of the family Bunyaviridae, causes high rates of abortion and fetal malformation in infected ruminants as well as causing neurological disorders, blindness, or lethal hemorrhagic fever in humans. RVFV is classified as a category A priority pathogen and a select agent in the U.S., and currently there are no therapeutics available for RVF patients. NSs protein, a major virulence factor of RVFV, inhibits host transcription including interferon (IFN-β mRNA synthesis and promotes degradation of dsRNA-dependent protein kinase (PKR. NSs self-associates at the C-terminus 17 aa., while NSs at aa.210-230 binds to Sin3A-associated protein (SAP30 to inhibit the activation of IFN-β promoter. Thus, we hypothesize that NSs function(s can be abolished by truncation of specific domains, and co-expression of nonfunctional NSs with intact NSs will result in the attenuation of NSs function by dominant-negative effect. Unexpectedly, we found that RVFV NSs truncated at aa. 6-30, 31-55, 56-80, 81-105, 106-130, 131-155, 156-180, 181-205, 206-230, 231-248 or 249-265 lack functions of IFN-β mRNA synthesis inhibition and degradation of PKR. Truncated NSs were less stable in infected cells, while nuclear localization was inhibited in NSs lacking either of aa.81-105, 106-130, 131-155, 156-180, 181-205, 206-230 or 231-248. Furthermore, none of truncated NSs had exhibited significant dominant-negative functions for NSs-mediated IFN-β suppression or PKR degradation upon co-expression in cells infected with RVFV. We also found that any of truncated NSs except for intact NSs does not interact with RVFV NSs even in the presence of intact C-terminus self-association domain. Our results suggest that conformational integrity of NSs is important for the stability, cellular localization and biological functions of RVFV NSs, and the co-expression of truncated NSs does not exhibit dominant-negative phenotype.

Truncated Dual-Cap Nucleation Site Development

Science.gov (United States)

Matson, Douglas M.; Sander, Paul J.

2012-01-01

During heterogeneous nucleation within a metastable mushy-zone, several geometries for nucleation site development must be considered. Traditional spherical dual cap and crevice models are compared to a truncated dual cap to determine the activation energy and critical cluster growth kinetics in ternary Fe-Cr-Ni steel alloys. Results of activation energy results indicate that nucleation is more probable at grain boundaries within the solid than at the solid-liquid interface.

Risk factors and predictors of Torsade de pointes ventricular tachycardia in patients with left ventricular systolic dysfunction receiving Dofetilide

DEFF Research Database (Denmark)

Pedersen, Henriette Sloth; Elming, Hanne; Seibaek, Marie

2007-01-01

The purpose of this study was to identify risk factors of Torsade de pointes (TdP) ventricular tachycardia in patients medicated with a class III antiarrhythmic drug (dofetilide) and left ventricular systolic dysfunction with heart failure (HF) or recent myocardial infarction (MI). The 2 Danish...

Left main percutaneous coronary intervention.

Science.gov (United States)

Teirstein, Paul S; Price, Matthew J

2012-10-23

The introduction of drug-eluting stents and advances in catheter techniques have led to increasing acceptance of percutaneous coronary intervention (PCI) as a viable alternative to coronary artery bypass graft (CABG) for unprotected left main disease. Current guidelines state that it is reasonable to consider unprotected left main PCI in patients with low to intermediate anatomic complexity who are at increased surgical risk. Data from randomized trials involving patients who are candidates for either treatment strategy provide novel insight into the relative safety and efficacy of PCI for this lesion subset. Herein, we review the current data comparing PCI with CABG for left main disease, summarize recent guideline recommendations, and provide an update on technical considerations that may optimize clinical outcomes in left main PCI. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Symmetric truncations of the shallow-water equations

International Nuclear Information System (INIS)

Rouhi, A.; Abarbanel, H.D.I.

1993-01-01

Conservation of potential vorticity in Eulerian fluids reflects particle interchange symmetry in the Lagrangian fluid version of the same theory. The algebra associated with this symmetry in the shallow-water equations is studied here, and we give a method for truncating the degrees of freedom of the theory which preserves a maximal number of invariants associated with this algebra. The finite-dimensional symmetry associated with keeping only N modes of the shallow-water flow is SU(N). In the limit where the number of modes goes to infinity (N→∞) all the conservation laws connected with potential vorticity conservation are recovered. We also present a Hamiltonian which is invariant under this truncated symmetry and which reduces to the familiar shallow-water Hamiltonian when N→∞. All this provides a finite-dimensional framework for numerical work with the shallow-water equations which preserves not only energy and enstrophy but all other known conserved quantities consistent with the finite number of degrees of freedom. The extension of these ideas to other nearly two-dimensional flows is discussed

Autocorrelation as a source of truncated Lévy flights in foreign exchange rates

Science.gov (United States)

Figueiredo, Annibal; Gleria, Iram; Matsushita, Raul; Da Silva, Sergio

2003-05-01

We suggest that the ultraslow speed of convergence associated with truncated Lévy flights (Phys. Rev. Lett. 73 (1994) 2946) may well be explained by autocorrelations in data. We show how a particular type of autocorrelation generates power laws consistent with a truncated Lévy flight. Stock exchanges have been suggested to be modeled by a truncated Lévy flight (Nature 376 (1995) 46; Physica A 297 (2001) 509; Econom. Bull. 7 (2002) 1). Here foreign exchange rate data are taken instead. Scaling power laws in the “probability of return to the origin” are shown to emerge for most currencies. A novel approach to measure how distant a process is from a Gaussian regime is presented.

Restricted N-terminal truncation of cardiac troponin T: a novel mechanism for functional adaptation to energetic crisis.

Science.gov (United States)

Feng, Han-Zhong; Biesiadecki, Brandon J; Yu, Zhi-Bin; Hossain, M Moazzem; Jin, J-P

2008-07-15

The N-terminal variable region of cardiac troponin T (TnT) is a regulatory structure that can be selectively removed during myocardial ischaemia reperfusion by mu-calpain proteolysis. Here we investigated the pathophysiological significance of this post-translational modification that removes amino acids 1-71 of cardiac TnT. Working heart preparations were employed to study rat acute myocardial infarction and transgenic mouse hearts over-expressing the N-terminal truncated cardiac TnT (cTnT-ND). Ex vivo myocardial infarction by ligation of the left anterior descending coronary artery induced heart failure and produced cTnT-ND not only in the infarct but also in remote zones, including the right ventricular free wall, indicating a whole organ response in the absence of systemic neurohumoral mechanisms. Left ventricular pressure overload in mouse working hearts produced increased cTnT-ND in both ventricles, suggesting a role of haemodynamic stress in triggering an acute whole organ proteolytic regulation. Transgenic mouse hearts in which the endogenous intact cardiac TnT was partially replaced by cTnT-ND showed lowered contractile velocity. When afterload increased from 55 mmHg to 90 mmHg, stroke volume decreased in the wild type but not in the transgenic mouse hearts. Correspondingly, the left ventricular rapid-ejection time of the transgenic mouse hearts was significantly longer than that of wild type hearts, especially at high afterload. The restricted deletion of the N-terminal variable region of cardiac troponin T demonstrates a novel mechanism by which the thin filament regulation adapts to sustain cardiac function under stress conditions.

A Residual Approach for Balanced Truncation Model Reduction (BTMR of Compartmental Systems

Directory of Open Access Journals (Sweden)

William La Cruz

2014-05-01

Full Text Available This paper presents a residual approach of the square root balanced truncation algorithm for model order reduction of continuous, linear and time-invariante compartmental systems. Specifically, the new approach uses a residual method to approximate the controllability and observability gramians, whose resolution is an essential step of the square root balanced truncation algorithm, that requires a great computational cost. Numerical experiences are included to highlight the efficacy of the proposed approach.

Rotating D0-branes and consistent truncations of supergravity

International Nuclear Information System (INIS)

Anabalón, Andrés; Ortiz, Thomas; Samtleben, Henning

2013-01-01

The fluctuations around the D0-brane near-horizon geometry are described by two-dimensional SO(9) gauged maximal supergravity. We work out the U(1) 4 truncation of this theory whose scalar sector consists of five dilaton and four axion fields. We construct the full non-linear Kaluza–Klein ansatz for the embedding of the dilaton sector into type IIA supergravity. This yields a consistent truncation around a geometry which is the warped product of a two-dimensional domain wall and the sphere S 8 . As an application, we consider the solutions corresponding to rotating D0-branes which in the near-horizon limit approach AdS 2 ×M 8 geometries, and discuss their thermodynamical properties. More generally, we study the appearance of such solutions in the presence of non-vanishing axion fields

Calculation of the ALMA Risk of Right Ventricular Failure After Left Ventricular Assist Device Implantation.

Science.gov (United States)

Loforte, Antonio; Montalto, Andrea; Musumeci, Francesco; Amarelli, Cristiano; Mariani, Carlo; Polizzi, Vincenzo; Lilla Della Monica, Paola; Grigioni, Francesco; Di Bartolomeo, Roberto; Marinelli, Giuseppe

2018-05-08

Right ventricular failure after continuous-flow left ventricular assist device (LVAD) implantation is still an unsolved issue and remains a life-threatening event for patients. We undertook this study to determine predictors of the patients who are candidates for isolated LVAD therapy as opposed to biventricular support (BVAD). We reviewed demographic, echocardiographic, hemodynamic, and laboratory variables for 258 patients who underwent both isolated LVAD implantation and unplanned BVAD because of early right ventricular failure after LVAD insertion, between 2006 and 2017 (LVAD = 170 and BVAD = 88). The final study patients were randomly divided into derivation (79.8%, n = 206) and validation (20.1%, n = 52) cohorts. Fifty-seven preoperative risk factors were compared between patients who were successfully managed with an LVAD and those who required a BVAD. Nineteen variables demonstrated statistical significance on univariable analysis. Multivariable logistic regression analysis identified destination therapy (odds ratio [OR] 2.0 [1.7-3.9], p = 0.003), a pulmonary artery pulsatility index right ventricle/left ventricle end-diastolic diameter ratio >0.75 (OR 2.7 [1.5-5.5], p = 0.001), an right ventricle stroke work index 17 (OR 3.5 [1.9-6.9], p the major predictors of the need for BVAD. Using these data, we propose a simple risk calculator to determine the suitability of patients for isolated LVAD support in the era of continuous-flow mechanical circulatory support devices.

Left atrial remodelling in patients with myocardial infarction complicated by heart failure, left ventricular dysfunction, or both: the VALIANT Echo study

DEFF Research Database (Denmark)

Meris, Alessandra; Amigoni, Maria; Uno, Hajime

2009-01-01

AIMS: To assess the relationship between left atrial (LA) size and outcome after high-risk myocardial infarction (MI) and to study dynamic changes in LA size during long-term follow-up. METHODS AND RESULTS: The VALIANT Echocardiography study prospectively enrolled 610 patients with left ventricul...

A protein-truncating R179X variant in RNF186 confers protection against ulcerative colitis

NARCIS (Netherlands)

Rivas, Manuel A.; Graham, Daniel; Sulem, Patrick; Stevens, Christine; Desch, A. Nicole; Goyette, Philippe; Gudbjartsson, Daniel; Jonsdottir, Ingileif; Thorsteinsdottir, Unnur; Degenhardt, Frauke; Mucha, Soeren; Kurki, Mitja I.; Li, Dalin; D'Amato, Mauro; Annese, Vito; Vermeire, Severine; Weersma, Rinse K.; Halfvarson, Jonas; Paavola-Sakki, Paulina; Lappalainen, Maarit; Lek, Monkol; Cummings, Beryl; Tukiainen, Taru; Haritunians, Talin; Halme, Leena; Koskinen, Lotta L. E.; Ananthakrishnan, Ashwin N.; Luo, Yang; Heap, Graham A.; Visschedijk, Marijn C.; MacArthur, Daniel G.; Neale, Benjamin M.; Ahmad, Tariq; Anderson, Carl A.; Brant, Steven R.; Duerr, Richard H.; Silverberg, Mark S.; Cho, Judy H.; Palotie, Aarno; Saavalainen, Paivi; Kontula, Kimmo; Farkkila, Martti; McGovern, Dermot P. B.; Franke, Andre; Stefansson, Kari; Rioux, John D.; Xavier, Ramnik J.; Daly, Mark J.

Protein-truncating variants protective against human disease provide in vivo validation of therapeutic targets. Here we used targeted sequencing to conduct a search for protein-truncating variants conferring protection against inflammatory bowel disease exploiting knowledge of common variants

Predictors of the left ventricular dysfunction induced by ventricular arrhythmia

Directory of Open Access Journals (Sweden)

А. І. Vytryhovskiy

2016-08-01

Full Text Available The most powerful predictor of life-threatening arrhythmia risk is a combination of low heart rate variability with low ejection fraction (EF of the left ventricle. Aim. To identify predictors of left ventricle dysfunction which is induced by ventricular arrhythmia. Materials and methods. To diagnose structural changes of left ventricular functional capacity and reserves in patients with previous myocardial infarction and patients with high and very high cardiovascular risk by SCORE scale and for establishment the relationship between morphological heart changes and pathological phenomenon of heart turbulence echocardiography and study of heart rate turbulence variability were performed. 603 patients were selected for the research. All patients were divided into groups: group 1 – patients with coronary heart disease, but without associated risk factors, such as smoking, obesity, metabolic syndrome; group 2 – patients who smoke tobacco more than 2 years (very high cardiovascular risk by scale SCORE; group 3 – patients with metabolic syndrome without coronary heart disease or arterial hypertension (very high cardiovascular risk by scale SCORE. The control group consisted of 149 persons. Results. The feature of structural changes in patients with myocardial infarction and in patients with a high cardiovascular risk by SCORE with heart rate turbulence compared with cases without НRT is considerably thickening of the left interventricular septum in systole. Based on this, it can be argued that the emergence of ventricular arrhythmia and accordingly phenomenon of heart rate turbulence in patients with existing cardiovascular diseases and risk factors has both morphological and functional character. Significant difference of echocardioscopy parameters in patients with postinfarction cardiosclerosis and risk factors by the SCORE system was established by index of intraventricular septum thickness in systole, and in persons with high risk – in

Lymphoscintigraphy for sentinel lymph node detection in breast cancer: usefulness of image truncation

International Nuclear Information System (INIS)

Carrier, P.; Remp, H.J.; Chaborel, J.P.; Lallement, M.; Bussiere, F.; Darcourt, J.; Lallement, M.; Leblanc-Talent, P.; Machiavello, J.C.; Ettore, F.

2004-01-01

The sentinel lymph node (SNL) detection in breast cancer has been recently validated. It allows the reduction of the number of axillary dissections and their corresponding side effects. We tested a simple method of image truncation in order to improve the sensitivity of lymphoscintigraphy. This approach is justified by the magnitude of uptake difference between the injection site and the SNL. We prospectively investigated SNL detection using a triple method (lymphoscintigraphy, blue dye and surgical radio detection) in 130 patients. SNL was identified in 104 of the 132 patients (80%) using the standard images and in 126 of them (96, 9%) using the truncated images. Blue dye detection and surgical radio detection had a sensitivity of 76,9% and 98,5% respectively. The false negative rate was 10,3%. 288 SNL were dissected, 31 were metastatic. Among the 19 patients with metastatic SNL and more than one SNL detected, the metastatic SNL was not the hottest in 9 of them. 28 metastatic SNL were detected Y on truncated images versus only 19 on standard images. Truncation which dramatically increases the sensitivity of lymphoscintigraphy allows to increase the number of dissected SNL and probably reduces the false negative rate. (author)

Truncated forms of viral VP2 proteins fused to EGFP assemble into fluorescent parvovirus-like particles

Directory of Open Access Journals (Sweden)

Vuento Matti

2006-12-01

Full Text Available Abstract Fluorescence correlation spectroscopy (FCS monitors random movements of fluorescent molecules in solution, giving information about the number and the size of for example nano-particles. The canine parvovirus VP2 structural protein as well as N-terminal deletion mutants of VP2 (-14, -23, and -40 amino acids were fused to the C-terminus of the enhanced green fluorescent protein (EGFP. The proteins were produced in insect cells, purified, and analyzed by western blotting, confocal and electron microscopy as well as FCS. The non-truncated form, EGFP-VP2, diffused with a hydrodynamic radius of 17 nm, whereas the fluorescent mutants truncated by 14, 23 and 40 amino acids showed hydrodynamic radii of 7, 20 and 14 nm, respectively. These results show that the non-truncated EGFP-VP2 fusion protein and the EGFP-VP2 constructs truncated by 23 and by as much as 40 amino acids were able to form virus-like particles (VLPs. The fluorescent VLP, harbouring VP2 truncated by 23 amino acids, showed a somewhat larger hydrodynamic radius compared to the non-truncated EGFP-VP2. In contrast, the construct containing EGFP-VP2 truncated by 14 amino acids was not able to assemble into VLP-resembling structures. Formation of capsid structures was confirmed by confocal and electron microscopy. The number of fluorescent fusion protein molecules present within the different VLPs was determined by FCS. In conclusion, FCS provides a novel strategy to analyze virus assembly and gives valuable structural information for strategic development of parvovirus-like particles.

Fluorometric graphene oxide-based detection of Salmonella enteritis using a truncated DNA aptamer.

Science.gov (United States)

Chinnappan, Raja; AlAmer, Saleh; Eissa, Shimaa; Rahamn, Anas Abdel; Abu Salah, Khalid M; Zourob, Mohammed

2017-12-18

The work describes a fluorescence-based study for mapping the highest affinity truncated aptamer from the full length sequence and its integration in a graphene oxide platform for the detection of Salmonella enteriditis. To identify the best truncated sequence, molecular beacons and a displacement assay design are applied. In the fluorescence displacement assay, the truncated aptamer was hybridized with fluorescein and quencher-labeled complementary sequences to form a fluorescence/quencher pair. In the presence of S. enteritidis, the aptamer dissociates from the complementary labeled oligonucleotides and thus, the fluorescein/quencher pair becomes physically separated. This leads to an increase in fluorescence intensity. One of the truncated aptamers identified has a 2-fold lower dissociation constant (3.2 nM) compared to its full length aptamer (6.3 nM). The truncated aptamer selected in this process was used to develop a fluorometric graphene oxide (GO) based assay. If fluorescein-labeled aptamer is adsorbed on GO via π stacking interaction, fluorescence is quenched. However, in the presence of target (S. enteriditis), the labeled aptamers is released from surface to form a stable complex with the bacteria and fluorescence is restored, depending on the quantity of bacteria being present. The resulting assay has an unsurpassed detection limit of 25 cfu·mL -1 in the best case. The cross reactivity to Salmonella typhimurium, Staphylococcus aureus and Escherichia coli is negligible. The assay was applied to analyze doped milk samples for and gave good recovery. Thus, we believe that the truncated aptamer/graphene oxide platform is a potential tool for the detection of S. Enteritidis. Graphical abstract Fluorescently labelled aptamer against Salmonella enteritidis was adsorbed on the surface of graphene oxide by π-stacking interaction. This results in quenching of the fluorescence of the label. Addition of Salmonella enteritidis restores fluorescence, and this

Error bounds for augmented truncations of discrete-time block-monotone Markov chains under subgeometric drift conditions

OpenAIRE

Masuyama, Hiroyuki

2015-01-01

This paper studies the last-column-block-augmented northwest-corner truncation (LC-block-augmented truncation, for short) of discrete-time block-monotone Markov chains under subgeometric drift conditions. The main result of this paper is to present an upper bound for the total variation distance between the stationary probability vectors of a block-monotone Markov chain and its LC-block-augmented truncation. The main result is extended to Markov chains that themselves may not be block monoton...

Analytic Method for Pressure Recovery in Truncated Diffusers ...

African Journals Online (AJOL)

A prediction method is presented for the static pressure recovery in subsonic axisymmetric truncated conical diffusers. In the analysis, a turbulent boundary layer is assumed at the diffuser inlet and a potential core exists throughout the flow. When flow separation occurs, this approach cannot be used to predict the maximum ...

Rotating D0-branes and consistent truncations of supergravity

Energy Technology Data Exchange (ETDEWEB)

Anabalón, Andrés [Departamento de Ciencias, Facultad de Artes Liberales, Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Av. Padre Hurtado 750, Viña del Mar (Chile); Université de Lyon, Laboratoire de Physique, UMR 5672, CNRS École Normale Supérieure de Lyon 46, allée d' Italie, F-69364 Lyon cedex 07 (France); Ortiz, Thomas; Samtleben, Henning [Université de Lyon, Laboratoire de Physique, UMR 5672, CNRS École Normale Supérieure de Lyon 46, allée d' Italie, F-69364 Lyon cedex 07 (France)

2013-12-18

The fluctuations around the D0-brane near-horizon geometry are described by two-dimensional SO(9) gauged maximal supergravity. We work out the U(1){sup 4} truncation of this theory whose scalar sector consists of five dilaton and four axion fields. We construct the full non-linear Kaluza–Klein ansatz for the embedding of the dilaton sector into type IIA supergravity. This yields a consistent truncation around a geometry which is the warped product of a two-dimensional domain wall and the sphere S{sup 8}. As an application, we consider the solutions corresponding to rotating D0-branes which in the near-horizon limit approach AdS{sub 2}×M{sub 8} geometries, and discuss their thermodynamical properties. More generally, we study the appearance of such solutions in the presence of non-vanishing axion fields.

Generation of truncated recombinant form of tumor necrosis factor ...

African Journals Online (AJOL)

7. Original Research Article. Generation of truncated recombinant form of tumor necrosis factor ... as 6×His tagged using E.coli BL21 (DE3) expression system. The protein was ... proapoptotic signaling cascade through TNFR1. [5] which is ...

Intravascular ultrasound and angiographic demonstration of left main stem thrombus-high-risk presentation in a young adult with anabolic steroid abuse.

Science.gov (United States)

Garg, Pankaj; Davis, Gershan; Wilson, John Ian; Sivananthan, Mohan

2010-01-01

We present a case of acute myocardial infarction in a young adult with a history of anabolic steroid abuse. On diagnostic coronary angiography and intravascular ultrasound, he was found to have a distal left main stem thrombus extending into the proximal left anterior descending artery and a large intermediate vessel. As he was hemodynamically stable and pain-free, he was managed conservatively with triple antiplatelet therapy (aspirin, clopidogrel, and abciximab). This was also to avoid the risk of 'wiring the vessel,' especially if there was underlying dissection. Repeat angiography a few weeks later showed complete thrombus resolution. This is the first reported case of extensive left main stem thrombus in a young patient with anabolic steroid abuse. Management of such cases is not straightforward and our case highlights one approach to both diagnosis and treatment.

Etiological aspect of left-handedness in adolescents.

Science.gov (United States)

Dragović, Milan; Milenković, Sanja; Kocijancić, Dusica; Zlatko, Sram

2013-01-01

Lateralization of brain functions such as language and manual dominance (hand preferences and fine motor control) are most likely under genetic control. However, this does not preclude the effect of various environmental factors on functional brain lateralization. A strong association of non-right-handedness (left- and mixed-handedness) with various neurodevelopmental conditions (e.g. schizophrenia, autism, Rett syndrome) implies that in some cases, non-right-handedness may be acquired rather than inherited (i.e., pathologically determined). The aim of the study was: (a) re-investigation of several known risk factors for left-handedness (age of mother and/or father, twin pregnancies, and birth order), and (b) examination of hitherto uninvestigated factors (type of birth, Apgar score, maternal smoking during pregnancy). Putative, causative environmental agents for this shift in manual distributions are explored in a sample of 1031 high school students (404 males and 627 females) from Belgrade. Both pre-existing (age of parents, twin pregnancy, and birth order) and new (Apgar score, maternal smoking, type of birth) putative agents are examined. We found that maternal smoking and low Apgar score (2-6) can significantly increase risk for left-handedness (p=0.046 and p=0.042, respectively).The remaining factors showed no significant association with left-handedness in adolescents. Our study clearly demonstrates that left-handedness may be related to maternal smoking during pregnancy and a low Apgar score on birth.

Zlib: A numerical library for optimal design of truncated power series algebra and map parameterization routines

International Nuclear Information System (INIS)

Yan, Y.T.

1996-11-01

A brief review of the Zlib development is given. Emphasized is the Zlib nerve system which uses the One-Step Index Pointers (OSIPs) for efficient computation and flexible use of the Truncated Power Series Algebra (TPSA). Also emphasized is the treatment of parameterized maps with an object-oriented language (e.g. C++). A parameterized map can be a Vector Power Series (Vps) or a Lie generator represented by an exponent of a Truncated Power Series (Tps) of which each coefficient is an object of truncated power series

Measuring a truncated disk in Aquila X-1

DEFF Research Database (Denmark)

King, Ashley L.; Tomsick, John A.; Miller, Jon M.

2016-01-01

We present NuSTAR and Swift observations of the neutron star Aquila X-1 during the peak of its 2014 July outburst. The spectrum is soft with strong evidence for a broad Fe Kα line. Modeled with a relativistically broadened reflection model, we find that the inner disk is truncated with an inner r...

Causal analysis of ordinal treatments and binary outcomes under truncation by death.

Science.gov (United States)

Wang, Linbo; Richardson, Thomas S; Zhou, Xiao-Hua

2017-06-01

It is common that in multi-arm randomized trials, the outcome of interest is "truncated by death," meaning that it is only observed or well-defined conditioning on an intermediate outcome. In this case, in addition to pairwise contrasts, the joint inference for all treatment arms is also of interest. Under a monotonicity assumption we present methods for both pairwise and joint causal analyses of ordinal treatments and binary outcomes in presence of truncation by death. We illustrate via examples the appropriateness of our assumptions in different scientific contexts.

Fusion events lead to truncation of FOS in epithelioid hemangioma of bone

DEFF Research Database (Denmark)

van IJzendoorn, David G P; de Jong, Danielle; Romagosa, Cleofe

2015-01-01

in exon 4 of the FOS gene and the fusion event led to the introduction of a stop codon. In all instances, the truncation of the FOS gene would result in the loss of the transactivation domain (TAD). Using FISH probes we found a break in the FOS gene in two additional cases, in none of these cases...... differential diagnosis of vascular tumors of bone. Our data suggest that the translocation causes truncation of the FOS protein, with loss of the TAD, which is thereby a novel mechanism involved in tumorigenesis....

Truncatable bootstrap equations in algebraic form and critical surface exponents

Energy Technology Data Exchange (ETDEWEB)

Gliozzi, Ferdinando [Dipartimento di Fisica, Università di Torino andIstituto Nazionale di Fisica Nucleare - sezione di Torino,Via P. Giuria 1, Torino, I-10125 (Italy)

2016-10-10

We describe examples of drastic truncations of conformal bootstrap equations encoding much more information than that obtained by a direct numerical approach. A three-term truncation of the four point function of a free scalar in any space dimensions provides algebraic identities among conformal block derivatives which generate the exact spectrum of the infinitely many primary operators contributing to it. In boundary conformal field theories, we point out that the appearance of free parameters in the solutions of bootstrap equations is not an artifact of truncations, rather it reflects a physical property of permeable conformal interfaces which are described by the same equations. Surface transitions correspond to isolated points in the parameter space. We are able to locate them in the case of 3d Ising model, thanks to a useful algebraic form of 3d boundary bootstrap equations. It turns out that the low-lying spectra of the surface operators in the ordinary and the special transitions of 3d Ising model form two different solutions of the same polynomial equation. Their interplay yields an estimate of the surface renormalization group exponents, y{sub h}=0.72558(18) for the ordinary universality class and y{sub h}=1.646(2) for the special universality class, which compare well with the most recent Monte Carlo calculations. Estimates of other surface exponents as well as OPE coefficients are also obtained.

The truncated Wigner method for Bose-condensed gases: limits of validity and applications

International Nuclear Information System (INIS)

Sinatra, Alice; Lobo, Carlos; Castin, Yvan

2002-01-01

We study the truncated Wigner method applied to a weakly interacting spinless Bose-condensed gas which is perturbed away from thermal equilibrium by a time-dependent external potential. The principle of the method is to generate an ensemble of classical fields ψ(r) which samples the Wigner quasi-distribution function of the initial thermal equilibrium density operator of the gas, and then to evolve each classical field with the Gross-Pitaevskii equation. In the first part of the paper we improve the sampling technique over our previous work (Sinatra et al 2000 J. Mod. Opt. 47 2629-44) and we test its accuracy against the exactly solvable model of the ideal Bose gas. In the second part of the paper we investigate the conditions of validity of the truncated Wigner method. For short evolution times it is known that the time-dependent Bogoliubov approximation is valid for almost pure condensates. The requirement that the truncated Wigner method reproduces the Bogoliubov prediction leads to the constraint that the number of field modes in the Wigner simulation must be smaller than the number of particles in the gas. For longer evolution times the nonlinear dynamics of the noncondensed modes of the field plays an important role. To demonstrate this we analyse the case of a three-dimensional spatially homogeneous Bose-condensed gas and we test the ability of the truncated Wigner method to correctly reproduce the Beliaev-Landau damping of an excitation of the condensate. We have identified the mechanism which limits the validity of the truncated Wigner method: the initial ensemble of classical fields, driven by the time-dependent Gross-Pitaevskii equation, thermalizes to a classical field distribution at a temperature T class which is larger than the initial temperature T of the quantum gas. When T class significantly exceeds T a spurious damping is observed in the Wigner simulation. This leads to the second validity condition for the truncated Wigner method, T class - T

Evaluation of a Risk Awareness Perception Training Program on Novice Teen Driver Behavior at Left-Turn Intersections.

Science.gov (United States)

McDonald, Catherine C; Kandadai, Venk; Loeb, Helen; Seacrist, Thomas; Lee, Yi-Ching; Bonfiglio, Dana; Fisher, Donald L; Winston, Flaura K

Collisions at left turn intersections are among the most prevalent types of teen driver serious crashes, with inadequate surveillance as a key factor. Risk awareness perception training (RAPT) has shown effectiveness in improving hazard anticipation for latent hazards. The goal of this study was to determine if RAPT version 3 (RAPT-3) improved intersection turning behaviors among novice teen drivers when the hazards were not latent and frequent glancing to multiple locations at the intersection was needed. Teens aged 16-18 with ≤180 days of licensure were randomly assigned to: 1) an intervention group (n=18) that received RAPT-3 (Trained); or 2) a control group (n=19) that received no training (Untrained). Both groups completed RAPT-3 Baseline Assessment and the Trained group completed RAPT-3 Training and RAPT-3 Post Assessment. Training effects were evaluated on a driving simulator. Simulator ( gap selection errors and collisions ) and eye tracker ( traffic check errors) metrics from six left-turn stop sign controlled intersections in the Simulated Driving Assessment (SDA) were analyzed. The Trained group scored significantly higher in RAPT-3 Post Assessment than RAPT-3 Baseline Assessment (psign controlled intersections where the hazards were not latent. Our findings point to further research to better understand the challenges teens have with left turn intersections.

A SUZAKU OBSERVATION OF NGC 4593: ILLUMINATING THE TRUNCATED DISK

International Nuclear Information System (INIS)

Markowitz, A. G.; Reeves, J. N.

2009-01-01

We report results from a 2007 Suzaku observation of the Seyfert 1 AGN NGC 4593. The narrow Fe Kα emission line has a FWHM width ∼ 4000 km s -1 , indicating emission from ∼> 5000 R g . There is no evidence for a relativistically broadened Fe K line, consistent with the presence of a radiatively efficient outer disk which is truncated or transitions to an interior radiatively inefficient flow. The Suzaku observation caught the source in a low-flux state; comparison to a 2002 XMM-Newton observation indicates that the hard X-ray flux decreased by 3.6, while the Fe Kα line intensity and width σ each roughly halved. Two model-dependent explanations for the changes in Fe Kα line profile are explored. In one, the Fe Kα line width has decreased from ∼10,000 to ∼4000 km s -1 from 2002 to 2007, suggesting that the thin disk truncation/transition radius has increased from 1000-2000 to ∼>5000 R g . However, there are indications from other compact accreting systems that such truncation radii tend to be associated only with accretion rates relative to Eddington much lower than that of NGC 4593. In the second model, the line profile in the XMM-Newton observation consists of a time-invariant narrow component plus a broad component originating from the inner part of the truncated disk (∼300 R g ) which has responded to the drop in continuum flux. The Compton reflection component strength R is ∼ 1.1, consistent with the measured Fe Kα line total equivalent width with an Fe abundance 1.7 times the solar value. The modest soft excess, modeled well by either thermal bremsstrahlung emission or by Comptonization of soft seed photons in an optical thin plasma, has fallen by a factor of ∼20 from 2002 to 2007, ruling out emission from a region 5 lt-yr in size.

Observation of the dispersion of wedge waves propagating along cylinder wedge with different truncations by laser ultrasound technique

Science.gov (United States)

Jia, Jing; Zhang, Yu; Han, Qingbang; Jing, Xueping

2017-10-01

The research focuses on study the influence of truncations on the dispersion of wedge waves propagating along cylinder wedge with different truncations by using the laser ultrasound technique. The wedge waveguide models with different truncations were built by using finite element method (FEM). The dispersion curves were obtained by using 2D Fourier transformation method. Multiple mode wedge waves were observed, which was well agreed with the results estimated from Lagasse's empirical formula. We established cylinder wedge with radius of 3mm, 20° and 60°angle, with 0μm, 5μm, 10μm, 20μm, 30μm, 40μm, and 50μm truncations, respectively. It was found that non-ideal wedge tip caused abnormal dispersion of the mode of cylinder wedge, the modes of 20° cylinder wedge presents the characteristics of guide waves which propagating along hollow cylinder as the truncation increasing. Meanwhile, the modes of 60° cylinder wedge with truncations appears the characteristics of guide waves propagating along hollow cylinder, and its mode are observed clearly. The study can be used to evaluate and detect wedge structure.

Effect of left ventricular diastolic dysfunction on left atrial appendage function and thrombotic potential in nonvalvular atrial fibrillation.

Science.gov (United States)

Demirçelik, Muhammed Bora; Çetin, Mustafa; Çiçekcioğlu, Hülya; Uçar, Özgül; Duran, Mustafa

2014-05-01

We aimed to investigate effects of left ventricular diastolic dysfunction on left atrial appendage functions, spontaneous echo contrast and thrombus formation in patients with nonvalvular atrial fibrillation. In 58 patients with chronic nonvalvular atrial fibrilation and preserved left ventricular systolic function, left atrial appendage functions, left atrial spontaneous echo contrast grading and left ventricular diastolic functions were evaluated using transthoracic and transoesophageal echocardiogram. Patients divided in two groups: Group D (n=30): Patients with diastolic dysfunction, Group N (n=28): Patients without diastolic dysfunction. Categorical variables in two groups were evaluated with Pearson's chi-square or Fisher's exact test. The significance of the lineer correlation between the degree of spontaneous echo contrast (SEC) and clinical measurements was evaluated with Spearman's correlation analysis. Peak pulmonary vein D velocity of the Group D was significantly higher than the Group N (p=0.006). However, left atrial appendage emptying velocity, left atrial appendage lateral wall velocity, peak pulmonary vein S, pulmonary vein S/D ratio were found to be significantly lower in Group D (p=0.028, patrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities respectively (r=-0.438, r=-0.328, r=-0.233, r=-0.447). Left atrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities were significantly lower in SEC 2-3-4 than SEC 1 (p=0.003, p=0.029, patrial fibrillation and preserved left ventricular ejection fraction, left atrial appendage functions are decreased in patients with left ventricular diastolic dysfunction. Left ventricular diastolic dysfunction may constitute a potential risk for formation of thrombus and stroke.

Truncation artifact suppression in cone-beam radionuclide transmission CT using maximum likelihood techniques: evaluation with human subjects

International Nuclear Information System (INIS)

Manglos, S.H.

1992-01-01

Transverse image truncation can be a serious problem for human imaging using cone-beam transmission CT (CB-CT) implemented on a conventional rotating gamma camera. This paper presents a reconstruction method to reduce or eliminate the artifacts resulting from the truncation. The method uses a previously published transmission maximum likelihood EM algorithm, adapted to the cone-beam geometry. The reconstruction method is evaluated qualitatively using three human subjects of various dimensions and various degrees of truncation. (author)

Minimum decoding trellis length and truncation depth of wrap-around Viterbi algorithm for TBCC in mobile WiMAX

Directory of Open Access Journals (Sweden)

Liu Yu-Sun

2011-01-01

Full Text Available Abstract The performance of the wrap-around Viterbi decoding algorithm with finite truncation depth and fixed decoding trellis length is investigated for tail-biting convolutional codes in the mobile WiMAX standard. Upper bounds on the error probabilities induced by finite truncation depth and the uncertainty of the initial state are derived for the AWGN channel. The truncation depth and the decoding trellis length that yield negligible performance loss are obtained for all transmission rates over the Rayleigh channel using computer simulations. The results show that the circular decoding algorithm with an appropriately chosen truncation depth and a decoding trellis just a fraction longer than the original received code words can achieve almost the same performance as the optimal maximum likelihood decoding algorithm in mobile WiMAX. A rule of thumb for the values of the truncation depth and the trellis tail length is also proposed.

On the Truncated Pareto Distribution with applications

OpenAIRE

Zaninetti, Lorenzo; Ferraro, Mario

2008-01-01

The Pareto probability distribution is widely applied in different fields such us finance, physics, hydrology, geology and astronomy. This note deals with an application of the Pareto distribution to astrophysics and more precisely to the statistical analysis of mass of stars and of diameters of asteroids. In particular a comparison between the usual Pareto distribution and its truncated version is presented. Finally a possible physical mechanism that produces Pareto tails for the distributio...

On the propagation of truncated localized waves in dispersive silica

KAUST Repository

Salem, Mohamed; Bagci, Hakan

2010-01-01

Propagation characteristics of truncated Localized Waves propagating in dispersive silica and free space are numerically analyzed. It is shown that those characteristics are affected by the changes in the relation between the transverse spatial

Digestion proteomics: tracking lactoferrin truncation and peptide release during simulated gastric digestion.

Science.gov (United States)

Grosvenor, Anita J; Haigh, Brendan J; Dyer, Jolon M

2014-11-01

The extent to which nutritional and functional benefit is derived from proteins in food is related to its breakdown and digestion in the body after consumption. Further, detailed information about food protein truncation during digestion is critical to understanding and optimising the availability of bioactives, in controlling and limiting allergen release, and in minimising or monitoring the effects of processing and food preparation. However, tracking the complex array of products formed during the digestion of proteins is not easily accomplished using classical proteomics. We here present and develop a novel proteomic approach using isobaric labelling to mapping and tracking protein truncation and peptide release during simulated gastric digestion, using bovine lactoferrin as a model food protein. The relative abundance of related peptides was tracked throughout a digestion time course, and the effect of pasteurisation on peptide release assessed. The new approach to food digestion proteomics developed here therefore appears to be highly suitable not only for tracking the truncation and relative abundance of released peptides during gastric digestion, but also for determining the effects of protein modification on digestibility and potential bioavailability.

The Most Developmentally Truncated Fishes Show Extensive Hox Gene Loss and Miniaturized Genomes

Science.gov (United States)

Malmstrøm, Martin; Britz, Ralf; Matschiner, Michael; Tørresen, Ole K; Hadiaty, Renny Kurnia; Yaakob, Norsham; Tan, Heok Hui; Jakobsen, Kjetill Sigurd; Salzburger, Walter; Rüber, Lukas

2018-01-01

Abstract The world’s smallest fishes belong to the genus Paedocypris. These miniature fishes are endemic to an extreme habitat: the peat swamp forests in Southeast Asia, characterized by highly acidic blackwater. This threatened habitat is home to a large array of fishes, including a number of miniaturized but also developmentally truncated species. Especially the genus Paedocypris is characterized by profound, organism-wide developmental truncation, resulting in sexually mature individuals of <8 mm in length with a larval phenotype. Here, we report on evolutionary simplification in the genomes of two species of the dwarf minnow genus Paedocypris using whole-genome sequencing. The two species feature unprecedented Hox gene loss and genome reduction in association with their massive developmental truncation. We also show how other genes involved in the development of musculature, nervous system, and skeleton have been lost in Paedocypris, mirroring its highly progenetic phenotype. Further, our analyses suggest two mechanisms responsible for the genome streamlining in Paedocypris in relation to other Cypriniformes: severe intron shortening and reduced repeat content. As the first report on the genomic sequence of a vertebrate species with organism-wide developmental truncation, the results of our work enhance our understanding of genome evolution and how genotypes are translated to phenotypes. In addition, as a naturally simplified system closely related to zebrafish, Paedocypris provides novel insights into vertebrate development. PMID:29684203

The Most Developmentally Truncated Fishes Show Extensive Hox Gene Loss and Miniaturized Genomes.

Science.gov (United States)

Malmstrøm, Martin; Britz, Ralf; Matschiner, Michael; Tørresen, Ole K; Hadiaty, Renny Kurnia; Yaakob, Norsham; Tan, Heok Hui; Jakobsen, Kjetill Sigurd; Salzburger, Walter; Rüber, Lukas

2018-04-01

The world's smallest fishes belong to the genus Paedocypris. These miniature fishes are endemic to an extreme habitat: the peat swamp forests in Southeast Asia, characterized by highly acidic blackwater. This threatened habitat is home to a large array of fishes, including a number of miniaturized but also developmentally truncated species. Especially the genus Paedocypris is characterized by profound, organism-wide developmental truncation, resulting in sexually mature individuals of <8 mm in length with a larval phenotype. Here, we report on evolutionary simplification in the genomes of two species of the dwarf minnow genus Paedocypris using whole-genome sequencing. The two species feature unprecedented Hox gene loss and genome reduction in association with their massive developmental truncation. We also show how other genes involved in the development of musculature, nervous system, and skeleton have been lost in Paedocypris, mirroring its highly progenetic phenotype. Further, our analyses suggest two mechanisms responsible for the genome streamlining in Paedocypris in relation to other Cypriniformes: severe intron shortening and reduced repeat content. As the first report on the genomic sequence of a vertebrate species with organism-wide developmental truncation, the results of our work enhance our understanding of genome evolution and how genotypes are translated to phenotypes. In addition, as a naturally simplified system closely related to zebrafish, Paedocypris provides novel insights into vertebrate development.

Identification of a functionally distinct truncated BDNF mRNA splice variant and protein in Trachemys scripta elegans.

Directory of Open Access Journals (Sweden)

Ganesh Ambigapathy

Full Text Available Brain-derived neurotrophic factor (BDNF has a diverse functional role and complex pattern of gene expression. Alternative splicing of mRNA transcripts leads to further diversity of mRNAs and protein isoforms. Here, we describe the regulation of BDNF mRNA transcripts in an in vitro model of eyeblink classical conditioning and a unique transcript that forms a functionally distinct truncated BDNF protein isoform. Nine different mRNA transcripts from the BDNF gene of the pond turtle Trachemys scripta elegans (tBDNF are selectively regulated during classical conditioning: exon I mRNA transcripts show no change, exon II transcripts are downregulated, while exon III transcripts are upregulated. One unique transcript that codes from exon II, tBDNF2a, contains a 40 base pair deletion in the protein coding exon that generates a truncated tBDNF protein. The truncated transcript and protein are expressed in the naïve untrained state and are fully repressed during conditioning when full-length mature tBDNF is expressed, thereby having an alternate pattern of expression in conditioning. Truncated BDNF is not restricted to turtles as a truncated mRNA splice variant has been described for the human BDNF gene. Further studies are required to determine the ubiquity of truncated BDNF alternative splice variants across species and the mechanisms of regulation and function of this newly recognized BDNF protein.

Identification of a functionally distinct truncated BDNF mRNA splice variant and protein in Trachemys scripta elegans.

Science.gov (United States)

Ambigapathy, Ganesh; Zheng, Zhaoqing; Li, Wei; Keifer, Joyce

2013-01-01

Brain-derived neurotrophic factor (BDNF) has a diverse functional role and complex pattern of gene expression. Alternative splicing of mRNA transcripts leads to further diversity of mRNAs and protein isoforms. Here, we describe the regulation of BDNF mRNA transcripts in an in vitro model of eyeblink classical conditioning and a unique transcript that forms a functionally distinct truncated BDNF protein isoform. Nine different mRNA transcripts from the BDNF gene of the pond turtle Trachemys scripta elegans (tBDNF) are selectively regulated during classical conditioning: exon I mRNA transcripts show no change, exon II transcripts are downregulated, while exon III transcripts are upregulated. One unique transcript that codes from exon II, tBDNF2a, contains a 40 base pair deletion in the protein coding exon that generates a truncated tBDNF protein. The truncated transcript and protein are expressed in the naïve untrained state and are fully repressed during conditioning when full-length mature tBDNF is expressed, thereby having an alternate pattern of expression in conditioning. Truncated BDNF is not restricted to turtles as a truncated mRNA splice variant has been described for the human BDNF gene. Further studies are required to determine the ubiquity of truncated BDNF alternative splice variants across species and the mechanisms of regulation and function of this newly recognized BDNF protein.

Etiological aspect of left-handedness in adolescents

Directory of Open Access Journals (Sweden)

Dragović Milan

2013-01-01

Full Text Available Introduction. Lateralization of brain functions such as language and manual dominance (hand preferences and fine motor control are most likely under genetic control. However, this does not preclude the effect of various environmental factors on functional brain lateralization. A strong association of non-right-handedness (left- and mixed-handedness with various neurodevelopmental conditions (e.g. schizophrenia, autism, Rett syndrome implies that in some cases, non-right-handedness may be acquired rather than inherited (i.e., pathologically determined. Objective. The aim of the study was: (a re-investigation of several known risk factors for left-handedness (age of mother and/or father, twin pregnancies, and birth order, and (b examination of hitherto uninvestigated factors (type of birth, Apgar score, maternal smoking during pregnancy. Methods. Putative, causative environmental agents for this shift in manual distributions are explored in a sample of 1031 high school students (404 males and 627 females from Belgrade. Both pre-existing (age of parents, twin pregnancy, and birth order and new (Apgar score, maternal smoking, type of birth putative agents are examined. Results. We found that maternal smoking and low Apgar score (2-6 can significantly increase risk for left-handedness (p=0.046 and p=0.042, respectively. The remaining factors showed no significant association with left-handedness in adolescents. Conclusion. Our study clearly demonstrates that left-handedness may be related to maternal smoking during pregnancy and a low Apgar score on birth.

Theoretical analysis of balanced truncation for linear switched systems

DEFF Research Database (Denmark)

Petreczky, Mihaly; Wisniewski, Rafal; Leth, John-Josef

2012-01-01

In this paper we present theoretical analysis of model reduction of linear switched systems based on balanced truncation, presented in [1,2]. More precisely, (1) we provide a bound on the estimation error using L2 gain, (2) we provide a system theoretic interpretation of grammians and their singu......In this paper we present theoretical analysis of model reduction of linear switched systems based on balanced truncation, presented in [1,2]. More precisely, (1) we provide a bound on the estimation error using L2 gain, (2) we provide a system theoretic interpretation of grammians...... for showing this independence is realization theory of linear switched systems. [1] H. R. Shaker and R. Wisniewski, "Generalized gramian framework for model/controller order reduction of switched systems", International Journal of Systems Science, Vol. 42, Issue 8, 2011, 1277-1291. [2] H. R. Shaker and R....... Wisniewski, "Switched Systems Reduction Framework Based on Convex Combination of Generalized Gramians", Journal of Control Science and Engineering, 2009....

Propagation of coherently combined truncated laser beam arrays with beam distortions in non-Kolmogorov turbulence.

Science.gov (United States)

Tao, Rumao; Si, Lei; Ma, Yanxing; Zhou, Pu; Liu, Zejin

2012-08-10

The propagation properties of coherently combined truncated laser beam arrays with beam distortions through non-Kolmogorov turbulence are studied in detail both analytically and numerically. The analytical expressions for the average intensity and the beam width of coherently combined truncated laser beam arrays with beam distortions propagating through turbulence are derived based on the combination of statistical optics methods and the extended Huygens-Fresnel principle. The effect of beam distortions, such as amplitude modulation and phase fluctuation, is studied by numerical examples. The numerical results reveal that phase fluctuations have significant influence on the spreading of coherently combined truncated laser beam arrays in non-Kolmogorov turbulence, and the effects of the phase fluctuations can be negligible as long as the phase fluctuations are controlled under a certain level, i.e., a>0.05 for the situation considered in the paper. Furthermore, large phase fluctuations can convert the beam distribution rapidly to a Gaussian form, vary the spreading, weaken the optimum truncation effects, and suppress the dependence of spreading on the parameters of the non-Kolmogorov turbulence.

Solving Schwinger-Dyson equations by truncation in zero-dimensional scalar quantum field theory

International Nuclear Information System (INIS)

Okopinska, A.

1991-01-01

Three sets of Schwinger-Dyson equations, for all Green's functions, for connected Green's functions, and for proper vertices, are considered in scalar quantum field theory. A truncation scheme applied to the three sets gives three different approximation series for Green's functions. For the theory in zero-dimensional space-time the results for respective two-point Green's functions are compared with the exact value calculated numerically. The best convergence of the truncation scheme is obtained for the case of proper vertices

Fitting Social Network Models Using Varying Truncation Stochastic Approximation MCMC Algorithm

KAUST Repository

Jin, Ick Hoon

2013-10-01

The exponential random graph model (ERGM) plays a major role in social network analysis. However, parameter estimation for the ERGM is a hard problem due to the intractability of its normalizing constant and the model degeneracy. The existing algorithms, such as Monte Carlo maximum likelihood estimation (MCMLE) and stochastic approximation, often fail for this problem in the presence of model degeneracy. In this article, we introduce the varying truncation stochastic approximation Markov chain Monte Carlo (SAMCMC) algorithm to tackle this problem. The varying truncation mechanism enables the algorithm to choose an appropriate starting point and an appropriate gain factor sequence, and thus to produce a reasonable parameter estimate for the ERGM even in the presence of model degeneracy. The numerical results indicate that the varying truncation SAMCMC algorithm can significantly outperform the MCMLE and stochastic approximation algorithms: for degenerate ERGMs, MCMLE and stochastic approximation often fail to produce any reasonable parameter estimates, while SAMCMC can do; for nondegenerate ERGMs, SAMCMC can work as well as or better than MCMLE and stochastic approximation. The data and source codes used for this article are available online as supplementary materials. © 2013 American Statistical Association, Institute of Mathematical Statistics, and Interface Foundation of North America.

Reduction of Truncation Errors in Planar Near-Field Aperture Antenna Measurements Using the Gerchberg-Papoulis Algorithm

DEFF Research Database (Denmark)

Martini, Enrica; Breinbjerg, Olav; Maci, Stefano

2008-01-01

A simple and effective procedure for the reduction of truncation errors in planar near-field measurements of aperture antennas is presented. The procedure relies on the consideration that, due to the scan plane truncation, the calculated plane wave spectrum of the field radiated by the antenna is...

Optimal auxiliary Hamiltonians for truncated boson-space calculations by means of a maximal-decoupling variational principle

International Nuclear Information System (INIS)

Li, C.

1991-01-01

A new method based on a maximal-decoupling variational principle is proposed to treat the Pauli-principle constraints for calculations of nuclear collective motion in a truncated boson space. The viability of the method is demonstrated through an application to the multipole form of boson Hamiltonians for the single-j and nondegenerate multi-j pairing interactions. While these boson Hamiltonians are Hermitian and contain only one- and two-boson terms, they are also the worst case for truncated boson-space calculations because they are not amenable to any boson truncations at all. By using auxiliary Hamiltonians optimally determined by the maximal-decoupling variational principle, however, truncations in the boson space become feasible and even yield reasonably accurate results. The method proposed here may thus be useful for doing realistic calculations of nuclear collective motion as well as for obtaining a viable interacting-boson-model type of boson Hamiltonian from the shell model

Percutaneous left atrial appendage closure for stroke prevention

DEFF Research Database (Denmark)

De Backer, Ole; Loupis, Anastasia M; Ihlemann, Nikolaj

2014-01-01

INTRODUCTION: In atrial fibrillation (AF) patients with an increased stroke risk, oral anticoagulation (OAC) is the standard treatment for stroke prevention. However, this therapy carries a high risk of major bleeding. Percutaneous closure of the left atrial appendage (LAA) is suggested as an alt...

Phase retrieval via incremental truncated amplitude flow algorithm

Science.gov (United States)

Zhang, Quanbing; Wang, Zhifa; Wang, Linjie; Cheng, Shichao

2017-10-01

This paper considers the phase retrieval problem of recovering the unknown signal from the given quadratic measurements. A phase retrieval algorithm based on Incremental Truncated Amplitude Flow (ITAF) which combines the ITWF algorithm and the TAF algorithm is proposed. The proposed ITAF algorithm enhances the initialization by performing both of the truncation methods used in ITWF and TAF respectively, and improves the performance in the gradient stage by applying the incremental method proposed in ITWF to the loop stage of TAF. Moreover, the original sampling vector and measurements are preprocessed before initialization according to the variance of the sensing matrix. Simulation experiments verified the feasibility and validity of the proposed ITAF algorithm. The experimental results show that it can obtain higher success rate and faster convergence speed compared with other algorithms. Especially, for the noiseless random Gaussian signals, ITAF can recover any real-valued signal accurately from the magnitude measurements whose number is about 2.5 times of the signal length, which is close to the theoretic limit (about 2 times of the signal length). And it usually converges to the optimal solution within 20 iterations which is much less than the state-of-the-art algorithms.

Learning Mixtures of Truncated Basis Functions from Data

DEFF Research Database (Denmark)

Langseth, Helge; Nielsen, Thomas Dyhre; Pérez-Bernabé, Inmaculada

2014-01-01

In this paper we investigate methods for learning hybrid Bayesian networks from data. First we utilize a kernel density estimate of the data in order to translate the data into a mixture of truncated basis functions (MoTBF) representation using a convex optimization technique. When utilizing a ke...... propose an alternative learning method that relies on the cumulative distribution function of the data. Empirical results demonstrate the usefulness of the approaches: Even though the methods produce estimators that are slightly poorer than the state of the art (in terms of log......In this paper we investigate methods for learning hybrid Bayesian networks from data. First we utilize a kernel density estimate of the data in order to translate the data into a mixture of truncated basis functions (MoTBF) representation using a convex optimization technique. When utilizing......-likelihood), they are significantly faster, and therefore indicate that the MoTBF framework can be used for inference and learning in reasonably sized domains. Furthermore, we show how a particular sub- class of MoTBF potentials (learnable by the proposed methods) can be exploited to significantly reduce complexity during inference....

Determination of αS from scaling violations of truncated moments of structure functions

International Nuclear Information System (INIS)

Forte, Stefano; Latorre, J.I.; Magnea, Lorenzo; Piccione, Andrea

2002-01-01

We determine the strong coupling α S (M Z ) from scaling violations of truncated moments of the nonsinglet deep inelastic structure function F 2 . Truncated moments are determined from BCDMS and NMC data using a neural network parametrization which retains the full experimental information on errors and correlations. Our method minimizes all sources of theoretical uncertainty and bias which characterize extractions of α S from scaling violations. We obtain α S (M Z )=0.124 +0.004 -0.007 (exp.) +0.003 -0.004 (th.)

Scavenger receptor AI/II truncation, lung function and COPD

DEFF Research Database (Denmark)

Thomsen, M; Nordestgaard, B G; Tybjaerg-Hansen, A

2011-01-01

The scavenger receptor A-I/II (SRA-I/II) on alveolar macrophages is involved in recognition and clearance of modified lipids and inhaled particulates. A rare variant of the SRA-I/II gene, Arg293X, truncates the distal collagen-like domain, which is essential for ligand recognition. We tested whet...

Effects of statistical quality, sampling rate and temporal filtering techniques on the extraction of functional parameters from the left ventricular time-activity curves

Energy Technology Data Exchange (ETDEWEB)

Guignard, P.A.; Chan, W. (Royal Melbourne Hospital, Parkville (Australia). Dept. of Nuclear Medicine)

1984-09-01

Several techniques for the processing of a series of curves derived from two left ventricular time-activity curves acquired at rest and during exercise with a nuclear stethoscope were evaluated. They were three and five point time smoothing. Fourier filtering preserving one to four harmonics (H), truncated curve Fourier filtering, and third degree polynomial curve fitting. Each filter's ability to recover, with fidelity, systolic and diastolic function parameters was evaluated under increasingly 'noisy' conditions and at several sampling rates. Third degree polynomial curve fittings and truncated Fourier filters exhibited very high sensitivity to noise. Three and five point time smoothing had moderate sensitivity to noise, but were highly affected by sampling rate. Fourier filtering preserving 2H or 3H produced the best compromise with high resilience to noise and independence of sampling rate as far as the recovery of these functional parameters is concerned.

Effects of statistical quality, sampling rate and temporal filtering techniques on the extraction of functional parameters from the left ventricular time-activity curves

International Nuclear Information System (INIS)

Guignard, P.A.; Chan, W.

1984-01-01

Several techniques for the processing of a series of curves derived from two left ventricular time-activity curves acquired at rest and during exercise with a nuclear stethoscope were evaluated. They were three and five point time smoothing. Fourier filtering preserving one to four harmonics (H), truncated curve Fourier filtering, and third degree polynomial curve fitting. Each filter's ability to recover, with fidelity, systolic and diastolic function parameters was evaluated under increasingly 'noisy' conditions and at several sampling rates. Third degree polynomial curve fittings and truncated Fourier filters exhibited very high sensitivity to noise. Three and five point time smoothing had moderate sensitivity to noise, but were highly affected by sampling rate. Fourier filtering preserving 2H or 3H produced the best compromise with high resilience to noise and independence of sampling rate as far as the recovery of these functional parameters is concerned. (author)

Risk factors, mortality, and timing of ischemic and hemorrhagic stroke with left ventricular assist devices.

Science.gov (United States)

Frontera, Jennifer A; Starling, Randall; Cho, Sung-Min; Nowacki, Amy S; Uchino, Ken; Hussain, M Shazam; Mountis, Maria; Moazami, Nader

2017-06-01

Stroke is a major cause of mortality after left ventricular assist device (LVAD) placement. Prospectively collected data of patients with HeartMate II (n = 332) and HeartWare (n = 70) LVADs from October 21, 2004, to May 19, 2015, were reviewed. Predictors of early (during index hospitalization) and late (post-discharge) ischemic and hemorrhagic stroke and association of stroke subtypes with mortality were assessed. Of 402 patients, 83 strokes occurred in 69 patients (17%; 0.14 events per patient-year [EPPY]): early ischemic stroke in 18/402 (4%; 0.03 EPPY), early hemorrhagic stroke in 11/402 (3%; 0.02 EPPY), late ischemic stroke in 25/402 (6%; 0.04 EPPY) and late hemorrhagic stroke in 29/402 (7%; 0.05 EPPY). Risk of stroke and death among patients with stroke was bimodal with highest risks immediately post-implant and increasing again 9-12 months later. Risk of death declined over time in patients without stroke. Modifiable stroke risk factors varied according to timing and stroke type, including tobacco use, bacteremia, pump thrombosis, pump infection, and hypertension (all p hemorrhagic stroke (adjusted odds ratio [aOR] 4.3, 95% confidence interval [CI] 1.0-17.8, p = 0.04), late ischemic stroke (aOR 3.2, 95% CI 1.1-9.0, p = 0.03), and late hemorrhagic stroke (aOR 3.7, 95% CI 1.5-9.2, p = 0.005) predicted death, whereas early ischemic stroke did not. Stroke is a leading cause and predictor of death in patients with LVADs. Risk of stroke and death among patients with stroke is bimodal, with highest risk at time of implant and increasing risk again after 9-12 months. Management of modifiable risk factors may reduce stroke and mortality rates. Copyright © 2017 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

Geographic origin as a determinant of left ventricular mass and diastolic function - the Cardiovascular Risk in Young Finns Study.

Science.gov (United States)

Vähämurto, L; Juonala, M; Ruohonen, S; Hutri-Kähönen, N; Kähönen, M; Laitinen, T; Tossavainen, P; Jokinen, E; Viikari, J; Raitakari, O T; Pahkala, K

2018-03-01

Eastern Finns have higher risk of coronary heart disease (CHD) and carotid intima-media thickness than western Finns although current differences in CHD risk factors are minimal. Left ventricular (LV) mass and diastolic function predict future cardiovascular events but their east-west differences are unknown. We examined the association of eastern/western baseline origin with LV mass and diastolic function. The study population included 2045 subjects of the Cardiovascular Risk in Young Finns Study with data from the baseline survey (1980) and the latest follow-up (2011) when echocardiography was performed at the age of 34-49 years. Subjects with eastern baseline origin had in 2011 higher LV mass (139±1.0 vs. 135±1.0 g, p=0.006) and E/e'-ratio indicating weaker LV diastolic function (4.86±0.03 vs. 4.74±0.03, p=0.02) than western subjects. Results were independent of age, sex, area of examination and CHD risk factors such as blood pressure and BMI (LV mass indexed with height: porigin (135±0.9 vs. 131±0.9 ml, p=0.0011) but left atrial end-systolic volume, also indicating LV diastolic function, was not different between eastern and western subjects (43.4±0.5 vs. 44.0±0.5 ml, p=0.45). Most of the subjects were well within the normal limits of these echocardiographic measurements. In our healthy middle-aged population, geographic origin in eastern Finland associated with higher LV mass compared to western Finland. Higher E/e'-ratio suggests that subjects with eastern baseline origin might have higher prevalence of diastolic dysfunction in the future than western subjects.

Performance Comparison of Assorted Color Spaces for Multilevel Block Truncation Coding based Face Recognition

OpenAIRE

H.B. Kekre; Sudeep Thepade; Karan Dhamejani; Sanchit Khandelwal; Adnan Azmi

2012-01-01

The paper presents a performance analysis of Multilevel Block Truncation Coding based Face Recognition among widely used color spaces. In [1], Multilevel Block Truncation Coding was applied on the RGB color space up to four levels for face recognition. Better results were obtained when the proposed technique was implemented using Kekre’s LUV (K’LUV) color space [25]. This was the motivation to test the proposed technique using assorted color spaces. For experimental analysis, two face databas...

The evidence for synthesis of truncated triangular silver nanoplates in the presence of CTAB

International Nuclear Information System (INIS)

He Xin; Zhao Xiujian; Chen Yunxia; Feng Jinyang

2008-01-01

Truncated triangular silver nanoplates were prepared by a solution-phase approach, which involved the seed-mediated growth of silver nanoparticles in the presence of cetyltrimethylammonium bromide (CTAB) at 40 deg. C. The result of X-ray diffraction indicates that the as-prepared nanoparticles are made of pure face centered cubic silver. Transmission electron microscopy and atomic force microscopy studies show that the truncated triangular silver nanoplates, with edge lengths of 50 ± 5 nm and thicknesses of 27 ± 3 nm, are oriented differently on substrates of a copper grid and a fresh mica flake. The corners of these nanoplates are round. The selected area electron diffraction analysis reveals that the silver nanoplates are single crystals with an atomically flat surface. We determine the holistic morphology of truncated triangular silver nanoplates through the above measurements with the aid of computer-aided 3D perspective images

Cross-layer combining of power control and adaptive modulation with truncated ARQ for cognitive radios

Institute of Scientific and Technical Information of China (English)

CHENG Shi-lun; YANG Zhen

2008-01-01

To maximize throughput and to satisfy users' requirements in cognitive radios, a cross-layer optimization problem combining adaptive modulation and power control at the physical layer and truncated automatic repeat request at the medium access control layer is proposed. Simulation results show the combination of power control, adaptive modulation, and truncated automatic repeat request can regulate transmitter powers and increase the total throughput effectively.

Dual scan CT image recovery from truncated projections

Science.gov (United States)

Sarkar, Shubhabrata; Wahi, Pankaj; Munshi, Prabhat

2017-12-01

There are computerized tomography (CT) scanners available commercially for imaging small objects and they are often categorized as mini-CT X-ray machines. One major limitation of these machines is their inability to scan large objects with good image quality because of the truncation of projection data. An algorithm is proposed in this work which enables such machines to scan large objects while maintaining the quality of the recovered image.

Tau truncation is a productive posttranslational modification of neurofibrillary degeneration in Alzheimer's disease.

Science.gov (United States)

Kovacech, B; Novak, M

2010-12-01

Deposits of the misfolded neuronal protein tau are major hallmarks of neurodegeneration in Alzheimer's disease (AD) and other tauopathies. The etiology of the transformation process of the intrinsically disordered soluble protein tau into the insoluble misordered aggregate has attracted much attention. Tau undergoes multiple modifications in AD, most notably hyperphosphorylation and truncation. Hyperphosphorylation is widely regarded as the hottest candidate for the inducer of the neurofibrillary pathology. However, the true nature of the impetus that initiates the whole process in the human brains remains unknown. In AD, several site-specific tau cleavages were identified and became connected to the progression of the disease. In addition, western blot analyses of tau species in AD brains reveal multitudes of various truncated forms. In this review we summarize evidence showing that tau truncation alone is sufficient to induce the complete cascade of neurofibrillary pathology, including hyperphosphorylation and accumulation of misfolded insoluble forms of tau. Therefore, proteolytical abnormalities in the stressed neurons and production of aberrant tau cleavage products deserve closer attention and should be considered as early therapeutic targets for Alzheimer's disease.

Parameter Estimation and Model Selection for Mixtures of Truncated Exponentials

DEFF Research Database (Denmark)

Langseth, Helge; Nielsen, Thomas Dyhre; Rumí, Rafael

2010-01-01

Bayesian networks with mixtures of truncated exponentials (MTEs) support efficient inference algorithms and provide a flexible way of modeling hybrid domains (domains containing both discrete and continuous variables). On the other hand, estimating an MTE from data has turned out to be a difficul...

Amplitude of Light Scattering by a Truncated Pyramid and Cone in the Rayleigh-Gans-Debye Approximation

Directory of Open Access Journals (Sweden)

Konstantin A. Shapovalov

2013-01-01

Full Text Available The article considers general approach to structured particle and particle system form factor calculation in the Rayleigh-Gans-Debye (RGD approximation. Using this approach, amplitude of light scattering by a truncated pyramid and cone formulas in RGD approximation are obtained. Light scattering indicator by a truncated pyramid and cone in the RGD approximation are calculated.

Previously known and newly diagnosed atrial fibrillation: a major risk indicator after a myocardial infarction complicated by heart failure or left ventricular dysfunction

DEFF Research Database (Denmark)

Køber, Lars; Swedberg, Karl; McMurray, John J V

2006-01-01

AIMS: To characterize the relationship between known and newly diagnosed atrial fibrillation (AF) and the risk of death and major cardiovascular (CV) events in patients with acute myocardial infarction (MI) complicated by heart failure (HF) and/or left ventricular systolic dysfunction (LVSD). MET...

Protoplanetary disc truncation mechanisms in stellar clusters: comparing external photoevaporation and tidal encounters

Science.gov (United States)

Winter, A. J.; Clarke, C. J.; Rosotti, G.; Ih, J.; Facchini, S.; Haworth, T. J.

2018-04-01

Most stars form and spend their early life in regions of enhanced stellar density. Therefore the evolution of protoplanetary discs (PPDs) hosted by such stars are subject to the influence of other members of the cluster. Physically, PPDs might be truncated either by photoevaporation due to ultraviolet flux from massive stars, or tidal truncation due to close stellar encounters. Here we aim to compare the two effects in real cluster environments. In this vein we first review the properties of well studied stellar clusters with a focus on stellar number density, which largely dictates the degree of tidal truncation, and far ultraviolet (FUV) flux, which is indicative of the rate of external photoevaporation. We then review the theoretical PPD truncation radius due to an arbitrary encounter, additionally taking into account the role of eccentric encounters that play a role in hot clusters with a 1D velocity dispersion σv ≳ 2 km/s. Our treatment is then applied statistically to varying local environments to establish a canonical threshold for the local stellar density (nc ≳ 104 pc-3) for which encounters can play a significant role in shaping the distribution of PPD radii over a timescale ˜3 Myr. By combining theoretical mass loss rates due to FUV flux with viscous spreading in a PPD we establish a similar threshold for which a massive disc is completely destroyed by external photoevaporation. Comparing these thresholds in local clusters we find that if either mechanism has a significant impact on the PPD population then photoevaporation is always the dominating influence.

SU-F-T-418: Evaluation of Organs at Risk (OAR) Sparing in Left Breast Irradiation Techniques

Energy Technology Data Exchange (ETDEWEB)

Saini, A [Oviedo, FL (United States); Hwang, C [FLHOSP, Altamonte Springs, Florida (United States); Das, I [Indiana University- School of Medicine, Indianapolis, IN (United States)

2016-06-15

Purpose: To compare dose to organs at risk (OAR) for left sided breast radiation therapy with comparable planning target volume (PTV) coverage in three techniques; free breathing in supine position (FB), deep inspirational breath hold in supine (DIBH) and free breathing in prone position (PP). Methods: Ten left sided breast cancer patients suitable for this study underwent a CT scan in three techniques e.g. supine, FB and DIBH and prone position (PP). One radiation oncologist contoured the PTV and OAR (cardiac components) based on RTOG guidelines. Treatment plans were optimized using field-in-field technique with AAA algorithm. Each plan was optimized to provide identical coverage to PTV such that a reasonable comparison in OAR dosimetry can be evaluated. The prescribed dose to PTV were 42.56 Gy; 2.66 Gy in 16 fractions. Results: Average lung dose parameters; Dmean, V10, V20 and V30 were 0.5 Gy, 0.6%, 0.2%, and 0.1% respectively in PP which is significantly lower than FB (5.9 Gy, 14.2%, 10.7 %, and 8.4%) and DIBH (5.8 Gy, 14.3%, 10.2%, 7.8%). Similarly average heart Dmean, V2.5, V5, V10, and V20 were much lower in PP (1.2Gy, 9.1%, 2.1%, 0.8%, and 0.4%), and in DIBH (1.2 Gy, 10.6%, 1.7%, 0.5%, and 0.1%) compared to FB (2.6 Gy, 21%, 7.2%, 4.4% and 3.3%) respectively. Similar findings were also noted in the heart component left anterior descending artery (LAD) and Left ventricle (LV) which are correlated to radiation related toxicity. Conclusion: Based on the calculated dose, FB technique provides highest heart and lung dose. Prone has lowest lung dose, and DIBH has lowest LAD dose. It is found that PP is always superior for heart, LV, LAD and lung as compared to FB. This conclusion is in contrast to some published study concluding that prone position has no benefit for heart sparing.

Risk Stratification of Patients With Current Generation Continuous-Flow Left Ventricular Assist Devices Being Bridged to Heart Transplantation.

Science.gov (United States)

Guha, Ashrith; Nguyen, Duc; Cruz-Solbes, Ana S; Amione-Guerra, Javier; Schutt, Robert C; Bhimaraj, Arvind; Trachtenberg, Barry H; Park, Myung H; Graviss, Edward A; Gaber, Osama; Suarez, Erik; Montane, Eva; Torre-Amione, Guillermo; Estep, Jerry D

Patients bridged to transplant (BTT) with continuous-flow left ventricular assist devices (CF-LVADs) have increased in the past decade. Decision support tools for these patients are limited. We developed a risk score to estimate prognosis and guide decision-making. We included heart transplant recipients bridged with CF-LVADs from the United Network for Organ Sharing (UNOS) database and divided them into development (2,522 patients) and validation cohorts (1,681 patients). Univariate and multivariate Cox proportional hazards models were performed. Variables that independently predicted outcomes (age, African American race, recipient body mass index [BMI], intravenous [IV] antibiotic use, pretransplant dialysis, and total bilirubin) were assigned weight using linear transformation, and risk scores were derived. Patients were grouped by predicted posttransplant mortality: low risk (≤ 38 points), medium risk (38-41 points), and high risk (≥ 42 points). We performed Cox proportional hazards analysis on wait-listed CF-LVAD patients who were not transplanted. Score significantly discriminated survival among the groups in the development cohort (6.7, 12.9, 20.7; p = 0.001), validation cohort (6.4, 10.1, 13.6; p assist device (LVAD) BTT risk score that effectively identifies CF-LVAD patients who are at higher risk for worse outcomes after heart transplant. This score may help physicians weigh the risks of transplantation in patients with CF-LVAD.

Five-dimensional truncation of the plane incompressible navier-stokes equations

Energy Technology Data Exchange (ETDEWEB)

Boldrighini, C [Camerino Univ. (Italy). Istituto di Matematica; Franceschini, V [Modena Univ. (Italy). Istituto Matematico

1979-01-01

A five-modes truncation of the Navier-Stokes equations for a two dimensional incompressible fluid on a torus is considered. A computer analysis shows that for a certain range of the Reynolds number the system exhibits a stochastic behaviour, approached through an involved sequence of bifurcations.

Exact method for the simulation of Coulombic systems by spherically truncated, pairwise r-1 summation

International Nuclear Information System (INIS)

Wolf, D.; Keblinski, P.; Phillpot, S.R.; Eggebrecht, J.

1999-01-01

Based on a recent result showing that the net Coulomb potential in condensed ionic systems is rather short ranged, an exact and physically transparent method permitting the evaluation of the Coulomb potential by direct summation over the r -1 Coulomb pair potential is presented. The key observation is that the problems encountered in determining the Coulomb energy by pairwise, spherically truncated r -1 summation are a direct consequence of the fact that the system summed over is practically never neutral. A simple method is developed that achieves charge neutralization wherever the r -1 pair potential is truncated. This enables the extraction of the Coulomb energy, forces, and stresses from a spherically truncated, usually charged environment in a manner that is independent of the grouping of the pair terms. The close connection of our approach with the Ewald method is demonstrated and exploited, providing an efficient method for the simulation of even highly disordered ionic systems by direct, pairwise r -1 summation with spherical truncation at rather short range, i.e., a method which fully exploits the short-ranged nature of the interactions in ionic systems. The method is validated by simulations of crystals, liquids, and interfacial systems, such as free surfaces and grain boundaries. copyright 1999 American Institute of Physics

Hyperbolic Cross Truncations for Stochastic Fourier Cosine Series

Science.gov (United States)

Zhang, Zhihua

2014-01-01

Based on our decomposition of stochastic processes and our asymptotic representations of Fourier cosine coefficients, we deduce an asymptotic formula of approximation errors of hyperbolic cross truncations for bivariate stochastic Fourier cosine series. Moreover we propose a kind of Fourier cosine expansions with polynomials factors such that the corresponding Fourier cosine coefficients decay very fast. Although our research is in the setting of stochastic processes, our results are also new for deterministic functions. PMID:25147842

Optical asymmetric cryptography based on elliptical polarized light linear truncation and a numerical reconstruction technique.

Science.gov (United States)

Lin, Chao; Shen, Xueju; Wang, Zhisong; Zhao, Cheng

2014-06-20

We demonstrate a novel optical asymmetric cryptosystem based on the principle of elliptical polarized light linear truncation and a numerical reconstruction technique. The device of an array of linear polarizers is introduced to achieve linear truncation on the spatially resolved elliptical polarization distribution during image encryption. This encoding process can be characterized as confusion-based optical cryptography that involves no Fourier lens and diffusion operation. Based on the Jones matrix formalism, the intensity transmittance for this truncation is deduced to perform elliptical polarized light reconstruction based on two intensity measurements. Use of a quick response code makes the proposed cryptosystem practical, with versatile key sensitivity and fault tolerance. Both simulation and preliminary experimental results that support theoretical analysis are presented. An analysis of the resistance of the proposed method on a known public key attack is also provided.

Associations of Blood Pressure Dipping Patterns With Left Ventricular Mass and Left Ventricular Hypertrophy in Blacks: The Jackson Heart Study.

Science.gov (United States)

Abdalla, Marwah; Caughey, Melissa C; Tanner, Rikki M; Booth, John N; Diaz, Keith M; Anstey, D Edmund; Sims, Mario; Ravenell, Joseph; Muntner, Paul; Viera, Anthony J; Shimbo, Daichi

2017-04-05

Abnormal diurnal blood pressure (BP), including nondipping patterns, assessed using ambulatory BP monitoring, have been associated with increased cardiovascular risk among white and Asian adults. We examined the associations of BP dipping patterns (dipping, nondipping, and reverse dipping) with cardiovascular target organ damage (left ventricular mass index and left ventricular hypertrophy), among participants from the Jackson Heart Study, an exclusively black population-based cohort. Analyses included 1015 participants who completed ambulatory BP monitoring and had echocardiography data from the baseline visit. Participants were categorized based on the nighttime to daytime systolic BP ratio into 3 patterns: dipping pattern (≤0.90), nondipping pattern (>0.90 to ≤1.00), and reverse dipping pattern (>1.00). The prevalence of dipping, nondipping, and reverse dipping patterns was 33.6%, 48.2%, and 18.2%, respectively. In a fully adjusted model, which included antihypertensive medication use and clinic and daytime systolic BP, the mean differences in left ventricular mass index between reverse dipping pattern versus dipping pattern was 8.3±2.1 g/m 2 ( P pattern versus dipping pattern was -1.0±1.6 g/m 2 ( P =0.536). Compared with participants with a dipping pattern, the prevalence ratio for having left ventricular hypertrophy was 1.65 (95% CI, 1.05-2.58) and 0.96 (95% CI, 0.63-1.97) for those with a reverse dipping pattern and nondipping pattern, respectively. In this population-based study of blacks, a reverse dipping pattern was associated with increased left ventricular mass index and a higher prevalence of left ventricular hypertrophy. Identification of a reverse dipping pattern on ambulatory BP monitoring may help identify black at increased risk for cardiovascular target organ damage. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

The Truncated Lognormal Distribution as a Luminosity Function for SWIFT-BAT Gamma-Ray Bursts

Directory of Open Access Journals (Sweden)

Lorenzo Zaninetti

2016-11-01

Full Text Available The determination of the luminosity function (LF in Gamma ray bursts (GRBs depends on the adopted cosmology, each one characterized by its corresponding luminosity distance. Here, we analyze three cosmologies: the standard cosmology, the plasma cosmology and the pseudo-Euclidean universe. The LF of the GRBs is firstly modeled by the lognormal distribution and the four broken power law and, secondly, by a truncated lognormal distribution. The truncated lognormal distribution fits acceptably the range in luminosity of GRBs as a function of the redshift.

Comparison of the effects of streptokinase and tissue plasminogen activator on regional wall motion after first myocardial infarction: analysis by the centerline method with correction for area at risk.

Science.gov (United States)

Cross, D B; Ashton, N G; Norris, R M; White, H D

1991-04-01

In a trial of streptokinase versus recombinant tissue-type plasminogen activator (rt-PA) for a first myocardial infarction, 270 patients were randomized. Regional left ventricular function was assessed in 214 patients at 3 weeks. The infarct-related artery was the left anterior descending artery in 78 patients, the right coronary artery in 122 and a dominant left circumflex artery in 14. Analysis was by the centerline method with a novel correction for the area of myocardium at risk, whereby the search region was determined by the anatomic distribution of the infarct-related artery. Infarct-artery patency at 3 weeks was 73% in the streptokinase group and 71% in the rt-PA group. Global left ventricular function did not differ between the two groups. Mean chord motion (+/- SD) in the most hypokinetic half of the defined search region was similar in the streptokinase and rt-PA groups (-2.4 +/- 1.5 versus -2.3 +/- 1.3, p = 0.63). There were no differences in hyperkinesia of the noninfarct zone. Compared with conventional centerline analysis, regional wall motion in the defined area at risk was significantly more abnormal. The two methods correlated strongly, however (r = 0.99, p less than 0.0001), and both methods produced similar overall results. Patients with a patent infarct-related artery and those with an occluded artery at the time of catheterization had similar levels of global function (ejection fraction 58 +/- 12% versus 57 +/- 12%, p = 0.58).(ABSTRACT TRUNCATED AT 250 WORDS)

Sudden death in patients with myocardial infarction and left ventricular dysfunction, heart failure, or both

DEFF Research Database (Denmark)

Solomon, Scott D; Zelenkofske, Steve; McMurray, John J V

2005-01-01

BACKGROUND: The risk of sudden death from cardiac causes is increased among survivors of acute myocardial infarction with reduced left ventricular systolic function. We assessed the risk and time course of sudden death in high-risk patients after myocardial infarction. METHODS: We studied 14......,609 patients with left ventricular dysfunction, heart failure, or both after myocardial infarction to assess the incidence and timing of sudden unexpected death or cardiac arrest with resuscitation in relation to the left ventricular ejection fraction. RESULTS: Of 14,609 patients, 1067 (7 percent) had an event...... percent confidence interval, 0.11 to 0.18 percent) after 2 years. Patients with a left ventricular ejection fraction of 30 percent or less were at highest risk in this early period (rate, 2.3 percent per month; 95 percent confidence interval, 1.8 to 2.8 percent). Nineteen percent of all sudden deaths...

Generation of truncated recombinant form of tumor necrosis factor ...

African Journals Online (AJOL)

Purpose: To produce truncated recombinant form of tumor necrosis factor receptor 1 (TNFR1), cysteine-rich domain 2 (CRD2) and CRD3 regions of the receptor were generated using pET28a and E. coli/BL21. Methods: DNA coding sequence of CRD2 and CRD3 was cloned into pET28a vector and the corresponding ...

Exact fan-beam image reconstruction algorithm for truncated projection data acquired from an asymmetric half-size detector

International Nuclear Information System (INIS)

Leng Shuai; Zhuang Tingliang; Nett, Brian E; Chen Guanghong

2005-01-01

In this paper, we present a new algorithm designed for a specific data truncation problem in fan-beam CT. We consider a scanning configuration in which the fan-beam projection data are acquired from an asymmetrically positioned half-sized detector. Namely, the asymmetric detector only covers one half of the scanning field of view. Thus, the acquired fan-beam projection data are truncated at every view angle. If an explicit data rebinning process is not invoked, this data acquisition configuration will reek havoc on many known fan-beam image reconstruction schemes including the standard filtered backprojection (FBP) algorithm and the super-short-scan FBP reconstruction algorithms. However, we demonstrate that a recently developed fan-beam image reconstruction algorithm which reconstructs an image via filtering a backprojection image of differentiated projection data (FBPD) survives the above fan-beam data truncation problem. Namely, we may exactly reconstruct the whole image object using the truncated data acquired in a full scan mode (2π angular range). We may also exactly reconstruct a small region of interest (ROI) using the truncated projection data acquired in a short-scan mode (less than 2π angular range). The most important characteristic of the proposed reconstruction scheme is that an explicit data rebinning process is not introduced. Numerical simulations were conducted to validate the new reconstruction algorithm

Non-compact left ventricle/hypertrabeculated left ventricle

International Nuclear Information System (INIS)

Restrepo, Gustavo; Castano, Rafael; Marmol, Alejandro

2005-01-01

Non-compact left ventricle/hypertrabeculated left ventricle is a myocardiopatie produced by an arrest of the normal left ventricular compaction process during the early embryogenesis. It is associated to cardiac anomalies (congenital cardiopaties) as well as to extracardial conditions (neurological, facial, hematologic, cutaneous, skeletal and endocrinological anomalies). This entity is frequently unnoticed, being diagnosed only in centers with great experience in the diagnosis and treatment of myocardiopathies. Many cases of non-compact left ventricle have been initially misdiagnosed as hypertrophic myocardiopatie, endocardial fibroelastosis, dilated cardiomyopatie, restrictive cardiomyopathy and endocardial fibrosis. It is reported the case of a 74 years old man with a history of chronic arterial hypertension and diabetes mellitus, prechordial chest pain and mild dyspnoea. An echocardiogram showed signs of non-compact left ventricle with prominent trabeculations and deep inter-trabecular recesses involving left ventricular apical segment and extending to the lateral and inferior walls. Literature on this topic is reviewed

Incidence and factors associated with infective endocarditis in patients undergoing left-sided heart valve replacement

DEFF Research Database (Denmark)

Østergaard, Lauge; Valeur, Nana; Ihlemann, Nikolaj

2018-01-01

Aims: Patients with left-sided heart valve replacement are considered at high-risk of infective endocarditis (IE). However, data on the incidence and risk factors associated with IE are sparse. Methods and results: Through Danish administrative registries, we identified patients who underwent left.......35-2.15), and cardiac implantable electronic device (CIED) (HR = 1.57, 95% CI 1.19-2.06) were among factors associated with an increased risk of IE. Conclusion: Infective endocarditis after left-sided heart valve replacement is not uncommon and occurs in about 1/20 over 10 years. Male, bioprosthetic valve, and heart...

Application of the AMPLE cluster-and-truncate approach to NMR structures for molecular replacement

Energy Technology Data Exchange (ETDEWEB)

Bibby, Jaclyn [University of Liverpool, Liverpool L69 7ZB (United Kingdom); Keegan, Ronan M. [Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Didcot OX11 0FA (United Kingdom); Mayans, Olga [University of Liverpool, Liverpool L69 7ZB (United Kingdom); Winn, Martyn D. [Science and Technology Facilities Council Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Rigden, Daniel J., E-mail: drigden@liv.ac.uk [University of Liverpool, Liverpool L69 7ZB (United Kingdom)

2013-11-01

Processing of NMR structures for molecular replacement by AMPLE works well. AMPLE is a program developed for clustering and truncating ab initio protein structure predictions into search models for molecular replacement. Here, it is shown that its core cluster-and-truncate methods also work well for processing NMR ensembles into search models. Rosetta remodelling helps to extend success to NMR structures bearing low sequence identity or high structural divergence from the target protein. Potential future routes to improved performance are considered and practical, general guidelines on using AMPLE are provided.

Transmural distribution of myocardial infarction: difference between the right and left ventricles in a canine model

International Nuclear Information System (INIS)

Ohzono, K.; Koyanagi, S.; Urabe, Y.; Harasawa, Y.; Tomoike, H.; Nakamura, M.

1986-01-01

The evolution of myocardial infarction 24 hours after ligating both the right coronary artery and the obtuse marginal branch of the left circumflex coronary artery was examined in 33 anesthetized dogs. Postmortem coronary angiography and a tracer microsphere technique were used to determine risk areas and their collateral blood flows, respectively. The mean weight of the risk areas was 11.3 +/- 0.5 g (mean +/- SEM) in the right ventricle and 10.5 +/- 0.9 g in the left ventricle (NS). The weight of infarcted tissue was 5.7 +/- 0.7 g in the right ventricle and 5.2 +/- 0.9 g in the left ventricle (NS). In both ventricles, infarct weight was linearly related to risk area size, and the percent of risk area necrosis was inversely correlated with the extent of collateral flow at 24 hours of coronary ligation, defined as the mean myocardial blood flow inside the central risk area. Ratios of infarct to risk area between the subendocardial and subepicardial layers were 0.76 +/- 0.06 and 0.28 +/- 0.05 in the right and left ventricles, respectively (p less than 0.01, between ventricles, n = 31), which coincided well with subendocardial-to-subepicardial-flow ratios at 24 hours, ie, 0.86 +/- 0.04 in the right ventricle and 0.32 +/- 0.06 in the left ventricle (p less than 0.01). The regional distribution of myocardial infarction correlated well with flow distribution inside the risk area; the slope of these relations was similar between the subendocardium and subepicardium in the right ventricle, whereas in the left ventricle it was larger in the subendocardium than in the subepicardium. Thus, in the dog, the inherent change in the regional distribution of coronary collateral blood flow is an important modifier in the evolution of myocardial infarction, especially in the left ventricle

Percutaneous closure of the left atrial appendage in patients with diabetes mellitus.

Science.gov (United States)

Azizy, Obayda; Rammos, Christos; Lehmann, Nils; Rassaf, Tienush; Kälsch, Hagen

2017-09-01

Left atrial appendage closure is a preventive treatment of atrial fibrillation-related thrombo-embolism. Patients with diabetes mellitus have increased risk for a negative outcome in percutaneous cardiac interventions. We assessed whether percutaneous left atrial appendage closure is safe and effective in patients with diabetes mellitus. We included 78 patients (mean age of 74.4 ± 8.3 years) with indication for left atrial appendage closure in an open-label observational single-centre study. Patients with diabetes mellitus ( n = 31) were at higher thrombo-embolic and bleeding risk (CHA 2 DS 2 -VASc: 4.5 ± 0.9, HAS-BLED: 4.7 ± 0.7) compared to patients without diabetes mellitus ( n = 47, CHA 2 DS 2 -VASc: 3.5 ± 1.0, HAS-BLED: 4.1 ± 0.8; p diabetes mellitus (Euro II-Score: 6.6 ± 3.7 vs 3.9 ± 1.9, p diabetes mellitus had no events ( p = 0.672). Follow-up of 6 months revealed no bleeding complication in both groups. No stroke occurred in follow-up, and left atrial appendage flow velocity reduction (55.6 ± 38.6 vs 51.4 ± 19.1 cm/s, p = 0.474) and rate of postinterventional leakage in the left atrial appendage were comparable (0% vs 2.1%, p = 0.672). Despite patients with diabetes mellitus are high-risk patients, the outcome of percutaneous left atrial appendage closure is similar to patients without diabetes mellitus.

The Extended Erlang-Truncated Exponential distribution: Properties and application to rainfall data.

Science.gov (United States)

Okorie, I E; Akpanta, A C; Ohakwe, J; Chikezie, D C

2017-06-01

The Erlang-Truncated Exponential ETE distribution is modified and the new lifetime distribution is called the Extended Erlang-Truncated Exponential EETE distribution. Some statistical and reliability properties of the new distribution are given and the method of maximum likelihood estimate was proposed for estimating the model parameters. The usefulness and flexibility of the EETE distribution was illustrated with an uncensored data set and its fit was compared with that of the ETE and three other three-parameter distributions. Results based on the minimized log-likelihood ([Formula: see text]), Akaike information criterion (AIC), Bayesian information criterion (BIC) and the generalized Cramér-von Mises [Formula: see text] statistics shows that the EETE distribution provides a more reasonable fit than the one based on the other competing distributions.

Truncation effects in the functional renormalization group study of spontaneous symmetry breaking

International Nuclear Information System (INIS)

Defenu, N.; Mati, P.; Márián, I.G.; Nándori, I.; Trombettoni, A.

2015-01-01

We study the occurrence of spontaneous symmetry breaking (SSB) for O(N) models using functional renormalization group techniques. We show that even the local potential approximation (LPA) when treated exactly is sufficient to give qualitatively correct results for systems with continuous symmetry, in agreement with the Mermin-Wagner theorem and its extension to systems with fractional dimensions. For general N (including the Ising model N=1) we study the solutions of the LPA equations for various truncations around the zero field using a finite number of terms (and different regulators), showing that SSB always occurs even where it should not. The SSB is signalled by Wilson-Fisher fixed points which for any truncation are shown to stay on the line defined by vanishing mass beta functions.

Relationship of left atrial enlargement to persistence or development of ECG left ventricular hypertrophy in hypertensive patients: implications for the development of new atrial fibrillation

DEFF Research Database (Denmark)

Okin, Peter M; Gerdts, Eva; Wachtell, Kristian

2010-01-01

Persistence and development of ECG left ventricular hypertrophy (LVH) by Cornell product criteria are associated with an increased risk of atrial fibrillation compared with regression or continued absence of LVH. We postulated that this association might be in part mediated via greater left atrial...... enlargement (LAE) in patients with new and persistent ECG LVH....

Firewalls as artefacts of inconsistent truncations of quantum geometries

Science.gov (United States)

Germani, Cristiano; Sarkar, Debajyoti

2016-01-01

In this paper we argue that a firewall is simply a manifestation of an inconsistent truncation of non-perturbative effects that unitarize the semiclassical black hole. Namely, we show that a naive truncation of quantum corrections to the Hawking spectrum at order ${\\cal O}(e^{-S})$, inexorably leads to a "localised'' divergent energy density near the black hole horizon. Nevertheless, in the same approximation, a distant observer only sees a discretised spectrum and concludes that unitarity is achieved by ${\\cal O}(e^{-S})$ effects. This is due to the fact that instead, the correct quantum corrections to the Hawking spectrum go like ${\\cal O}( g^{tt} e^{-S})$. Therefore, while at a distance far away from the horizon, where $g^{tt}\\approx 1$, quantum corrections {\\it are} perturbative, they {\\it do} diverge close to the horizon, where $g^{tt}\\rightarrow \\infty$. Nevertheless, these "corrections" nicely re-sum so that correlations functions are smooth at the would-be black hole horizon. Thus, we conclude that the appearance of firewalls is just a signal of the breaking of the semiclassical approximation at the Page time, even for large black holes.

A Novel SCCA Approach via Truncated ℓ1-norm and Truncated Group Lasso for Brain Imaging Genetics.

Science.gov (United States)

Du, Lei; Liu, Kefei; Zhang, Tuo; Yao, Xiaohui; Yan, Jingwen; Risacher, Shannon L; Han, Junwei; Guo, Lei; Saykin, Andrew J; Shen, Li

2017-09-18

Brain imaging genetics, which studies the linkage between genetic variations and structural or functional measures of the human brain, has become increasingly important in recent years. Discovering the bi-multivariate relationship between genetic markers such as single-nucleotide polymorphisms (SNPs) and neuroimaging quantitative traits (QTs) is one major task in imaging genetics. Sparse Canonical Correlation Analysis (SCCA) has been a popular technique in this area for its powerful capability in identifying bi-multivariate relationships coupled with feature selection. The existing SCCA methods impose either the ℓ 1 -norm or its variants to induce sparsity. The ℓ 0 -norm penalty is a perfect sparsity-inducing tool which, however, is an NP-hard problem. In this paper, we propose the truncated ℓ 1 -norm penalized SCCA to improve the performance and effectiveness of the ℓ 1 -norm based SCCA methods. Besides, we propose an efficient optimization algorithms to solve this novel SCCA problem. The proposed method is an adaptive shrinkage method via tuning τ . It can avoid the time intensive parameter tuning if given a reasonable small τ . Furthermore, we extend it to the truncated group-lasso (TGL), and propose TGL-SCCA model to improve the group-lasso-based SCCA methods. The experimental results, compared with four benchmark methods, show that our SCCA methods identify better or similar correlation coefficients, and better canonical loading profiles than the competing methods. This demonstrates the effectiveness and efficiency of our methods in discovering interesting imaging genetic associations. The Matlab code and sample data are freely available at http://www.iu.edu/∼shenlab/tools/tlpscca/ . © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Left regular bands of groups of left quotients

International Nuclear Information System (INIS)

El-Qallali, A.

1988-10-01

A semigroup S which has a left regular band of groups as a semigroup of left quotients is shown to be the semigroup which is a left regular band of right reversible cancellative semigroups. An alternative characterization is provided by using spinned products. These results are applied to the case where S is a superabundant whose set of idempotents forms a left normal band. (author). 13 refs

Reduction of truncation errors in planar near-field aperture antenna measurements using the method of alternating orthogonal projections

DEFF Research Database (Denmark)

Martini, Enrica; Breinbjerg, Olav; Maci, Stefano

2006-01-01

A simple and effective procedure for the reduction of truncation error in planar near-field to far-field transformations is presented. The starting point is the consideration that the actual scan plane truncation implies a reliability of the reconstructed plane wave spectrum of the field radiated...

Different truncation methods of AUC between Japan and the EU for bioequivalence assessment: influence on the regulatory judgment.

Science.gov (United States)

Oishi, Masayo; Chiba, Koji; Fukushima, Takashi; Tomono, Yoshiro; Suwa, Toshio

2012-01-01

In regulatory guidelines for bioequivalence (BE) assessment, the definitions of AUC for primary assessment are different in ICH countries, i.e., AUC from zero to the last sampling point (AUCall) in Japan, AUC from zero to infinity (AUCinf) or AUC from zero to the last measurable point (AUClast) in the US, and AUClast in the EU. To assure sufficient accuracy of truncated AUC for BE assessment, the ratio of truncated AUC (AUCall or AUClast) to AUCinf should be more than 80% both in Japanese and EU guidelines. We investigated how the difference in the definition of truncated AUC affects BE assessment of sustained release (SR) formulation. Our simulation result demonstrated that AUCall/AUCinf could be ≥80% despite AUClast/AUCinf being AUC affected the judgment of validity of truncated AUC for BE assessment, and AUCall could fail to detect the substantially different in vivo dissolution profile of generic drugs with SR formulation from the original drug.

Medical Image of the week: left ventricular non-compaction

Directory of Open Access Journals (Sweden)

Khoubyari R

2016-06-01

Full Text Available No abstract available. Article truncated at 150 words. A 38-year-old woman with history of type 2 diabetes mellitus and hypertension presented to emergency department with worsening exertional dyspnea and orthopnea for the past 2-3 months. She also reported a 14 pound weight gain within the 2 weeks prior to presentation. She denied any prior history of cardiac or pulmonary disease. Also, there was no family history of heart disease. She denies any recent sick contacts, smoking, alcohol drinking, or substance abuse. Physical exam revealed jugular venous pressure of 10 cm H2O and significant bilateral lower extremity pitting edema. Chest x-ray showed an enlarged cardiac silhouette. Brain naturetic peptide (BNP was 2,917 pg/mL. A subsequent echocardiogram revealed a left ventricular (LV ejection fraction of 23% with severe global LV hypokinesia with moderate mitral regurgitation. Thyroid panel as well as iron panel were within normal range. Other laboratories were unremarkable. For the new onset systolic heart failure, a coronary angiography was ...

Blood pressure and left ventricular hypertrophy during American-style football participation.

Science.gov (United States)

Weiner, Rory B; Wang, Francis; Isaacs, Stephanie K; Malhotra, Rajeev; Berkstresser, Brant; Kim, Jonathan H; Hutter, Adolph M; Picard, Michael H; Wang, Thomas J; Baggish, Aaron L

2013-07-30

Hypertension, a strong determinant of cardiovascular disease risk, has been documented among elite, professional American-style football (ASF) players. The risk of increased blood pressure (BP) and early adulthood hypertension among the substantially larger population of collegiate ASF athletes is not known. We conducted a prospective, longitudinal study to examine BP, the incidence of hypertension, and left ventricular remodeling among collegiate ASF athletes. Resting BP and left ventricular structure were assessed before and after a single season of competitive ASF participation in 6 consecutive groups of first-year university athletes (n=113). ASF participation was associated with significant increases in systolic BP (116±8 versus 125±13 mm Hg; Phistory of hypertension were the strongest independent predictors of postseason BP. Among linemen, there was a significant increase in the prevalence of concentric left ventricular hypertrophy (2 of 64 [3%] versus 20 of 64 [31%]; P<0.001) and change in left ventricular mass correlated with intraseason change in systolic BP (R=0.46, P<0.001). Collegiate ASF athletes may be at risk for clinically relevant increases in BP and the development of hypertension. Enhanced surveillance and carefully selected interventions may represent important opportunities to improve later-life cardiovascular health outcomes in this population.

High-definition transcranial direct current stimulation (HD-tDCS) of left dorsolateral prefrontal cortex affects performance in Balloon Analogue Risk Task (BART).

Science.gov (United States)

Guo, Heng; Zhang, Zhuoran; Da, Shu; Sheng, Xiaotian; Zhang, Xichao

2018-02-01

Studies on risk preferences have long been of great concern and have examined the neural basis underlying risk-based decision making. However, studies using conventional transcranial direct current stimulation (tDCS) revealed that bilateral stimulation could change risk propensity with limited evidence of precisely focalized unilateral high-definition transcranial direct current stimulation (HD-tDCS). The aim of this experiment was to investigate the effect of HD-tDCS focalizing the left dorsal lateral prefrontal cortex (DLPFC) on risk-taking behavior during the Balloon Analogue Risk Task (BART). This study was designed as a between-subject, single-blind, sham-controlled experiment. University students were randomly assigned to three groups: the anodal group (F3 anode, AF3, F1, F5, FC3 returned), the cathodal group (F3 cathodal, AF3, F1, F5, FC3 returned) and the sham group. Subsequently, 1.5-mA 20-min HD-tDCS was applied during the BART, and the Positive Affect and Negative Affect Scale (PANAS), the Sensation Seeking Scale-5 (SSS-5), and the Behavioral Inhibition System and Behavioral Approach System scale (BIS/BAS) were measured as control variables. The cathodal group earned less total money than the sham group, and no significant difference was observed between the anodal group and the sham group. These results showed that, to some extent, focalized unilateral cathodal HD-tDCS on left DLPFC could change performance during risky tasks and diminish risky decision making. Further studies are needed to investigate the dose effect and electrode distribution of HD-tDCS during risky tasks and examine synchronous brain activity to show the neural basis.

The Extended Erlang-Truncated Exponential distribution: Properties and application to rainfall data

Directory of Open Access Journals (Sweden)

I.E. Okorie

2017-06-01

Full Text Available The Erlang-Truncated Exponential ETE distribution is modified and the new lifetime distribution is called the Extended Erlang-Truncated Exponential EETE distribution. Some statistical and reliability properties of the new distribution are given and the method of maximum likelihood estimate was proposed for estimating the model parameters. The usefulness and flexibility of the EETE distribution was illustrated with an uncensored data set and its fit was compared with that of the ETE and three other three-parameter distributions. Results based on the minimized log-likelihood (−ℓˆ, Akaike information criterion (AIC, Bayesian information criterion (BIC and the generalized Cramér–von Mises W⋆ statistics shows that the EETE distribution provides a more reasonable fit than the one based on the other competing distributions. Keywords: Mathematics, Applied mathematics

Classification With Truncated Distance Kernel.

Science.gov (United States)

Huang, Xiaolin; Suykens, Johan A K; Wang, Shuning; Hornegger, Joachim; Maier, Andreas

2018-05-01

This brief proposes a truncated distance (TL1) kernel, which results in a classifier that is nonlinear in the global region but is linear in each subregion. With this kernel, the subregion structure can be trained using all the training data and local linear classifiers can be established simultaneously. The TL1 kernel has good adaptiveness to nonlinearity and is suitable for problems which require different nonlinearities in different areas. Though the TL1 kernel is not positive semidefinite, some classical kernel learning methods are still applicable which means that the TL1 kernel can be directly used in standard toolboxes by replacing the kernel evaluation. In numerical experiments, the TL1 kernel with a pregiven parameter achieves similar or better performance than the radial basis function kernel with the parameter tuned by cross validation, implying the TL1 kernel a promising nonlinear kernel for classification tasks.

Filter Factors of Truncated TLS Regularization with Multiple Observations

Czech Academy of Sciences Publication Activity Database

Hnětynková, I.; Plešinger, Martin; Žáková, J.

2017-01-01

Roč. 62, č. 2 (2017), s. 105-120 ISSN 0862-7940 R&D Projects: GA ČR GA13-06684S Institutional support: RVO:67985807 Keywords : truncated total least squares * multiple right-hand sides * eigenvalues of rank-d update * ill-posed problem * regularization * filter factors Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 0.618, year: 2016 http://hdl.handle.net/10338.dmlcz/146698

Identification of target genes for wild type and truncated HMGA2 in mesenchymal stem-like cells

DEFF Research Database (Denmark)

Henriksen, Jørn Mølgaard; Stabell, Marianne; Meza-Zepeda, Leonardo A

2010-01-01

The HMGA2 gene, coding for an architectural transcription factor involved in mesenchymal embryogenesis, is frequently deranged by translocation and/or amplification in mesenchymal tumours, generally leading to over-expression of shortened transcripts and a truncated protein.......The HMGA2 gene, coding for an architectural transcription factor involved in mesenchymal embryogenesis, is frequently deranged by translocation and/or amplification in mesenchymal tumours, generally leading to over-expression of shortened transcripts and a truncated protein....

Error Bounds for Augmented Truncations of Discrete-Time Block-Monotone Markov Chains under Geometric Drift Conditions

OpenAIRE

Masuyama, Hiroyuki

2014-01-01

In this paper we study the augmented truncation of discrete-time block-monotone Markov chains under geometric drift conditions. We first present a bound for the total variation distance between the stationary distributions of an original Markov chain and its augmented truncation. We also obtain such error bounds for more general cases, where an original Markov chain itself is not necessarily block monotone but is blockwise dominated by a block-monotone Markov chain. Finally,...

Free vibration of symmetric angle ply truncated conical shells under different boundary conditions using spline method

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, K. K.; Aziz, Z. A.; Javed, Saira; Yaacob, Y. [Universiti Teknologi Malaysia, Johor Bahru (Malaysia); Pullepu, Babuji [S R M University, Chennai (India)

2015-05-15

Free vibration of symmetric angle-ply laminated truncated conical shell is analyzed to determine the effects of frequency parameter and angular frequencies under different boundary condition, ply angles, different material properties and other parameters. The governing equations of motion for truncated conical shell are obtained in terms of displacement functions. The displacement functions are approximated by cubic and quintic splines resulting into a generalized eigenvalue problem. The parametric studies have been made and discussed.

Free vibration of symmetric angle ply truncated conical shells under different boundary conditions using spline method

International Nuclear Information System (INIS)

Viswanathan, K. K.; Aziz, Z. A.; Javed, Saira; Yaacob, Y.; Pullepu, Babuji

2015-01-01

Free vibration of symmetric angle-ply laminated truncated conical shell is analyzed to determine the effects of frequency parameter and angular frequencies under different boundary condition, ply angles, different material properties and other parameters. The governing equations of motion for truncated conical shell are obtained in terms of displacement functions. The displacement functions are approximated by cubic and quintic splines resulting into a generalized eigenvalue problem. The parametric studies have been made and discussed.

Increased infectivity in human cells and resistance to antibody-mediated neutralization by truncation of the SIV gp41 cytoplasmic tail

Directory of Open Access Journals (Sweden)

Takeo eKuwata

2013-05-01

Full Text Available The role of antibodies in protecting the host from human immunodeficiency virus type 1 (HIV-1 infection is of considerable interest, particularly because the RV144 trial results suggest that antibodies contribute to protection. Although infection of nonhuman primates with simian immunodeficiency virus (SIV is commonly used as an animal model of HIV-1 infection, the viral epitopes that elicit potent and broad neutralizing antibodies to SIV have not been identified. We isolated a monoclonal antibody (MAb B404 that potently and broadly neutralizes various SIV strains. B404 targets a conformational epitope comprising the V3 and V4 loops of Env that intensely exposed when Env binds CD4. B404-resistant variants were obtained by passaging viruses in the presence of increasing concentration of B404 in PM1/CCR5 cells. Genetic analysis revealed that the Q733stop mutation, which truncates the cytoplasmic tail of gp41, was the first major substitution in Env during passage. The maximal inhibition by B404 and other MAbs were significantly decreased against a recombinant virus with a gp41 truncation compared with the parental SIVmac316. This indicates that the gp41 truncation was associated with resistance to antibody-mediated neutralization. The infectivities of the recombinant virus with the gp41 truncation were 7900-fold, 1000-fold, and 140-fold higher than those of SIVmac316 in PM1, PM1/CCR5, and TZM-bl cells, respectively. Immunoblotting analysis revealed that the gp41 truncation enhanced the incorporation of Env into virions. The effect of the gp41 truncation on infectivity was not obvious in the HSC-F macaque cell line, although the resistance of viruses harboring the gp41 truncation to neutralization was maintained. These results suggest that viruses with a truncated gp41 cytoplasmic tail were selected by increased infectivity in human cells and by acquiring resistance to neutralizing antibody.

The lamppost model: effects of photon trapping, the bottom lamp and disc truncation

Science.gov (United States)

Niedźwiecki, Andrzej; Zdziarski, Andrzej A.

2018-04-01

We study the lamppost model, in which the primary X-ray sources in accreting black-hole systems are located symmetrically on the rotation axis on both sides of the black hole surrounded by an accretion disc. We show the importance of the emission of the source on the opposite side to the observer. Due to gravitational light bending, its emission can increase the direct (i.e., not re-emitted by the disc) flux by as much as an order of magnitude. This happens for near to face-on observers when the disc is even moderately truncated. For truncated discs, we also consider effects of emission of the top source gravitationally bent around the black hole. We also present results for the attenuation of the observed radiation with respect to that emitted by the lamppost as functions of the lamppost height, black-hole spin and the degree of disc truncation. This attenuation, which is due to the time dilation, gravitational redshift and the loss of photons crossing the black-hole horizon, can be as severe as by several orders of magnitude for low lamppost heights. We also consider the contribution to the observed flux due to re-emission by optically-thick matter within the innermost stable circular orbit.

Spectroscopic characterization of a truncated hemoglobin from the nitrogen-fixing bacterium Herbaspirillum seropedicae.

Science.gov (United States)

Razzera, Guilherme; Vernal, Javier; Baruh, Debora; Serpa, Viviane I; Tavares, Carolina; Lara, Flávio; Souza, Emanuel M; Pedrosa, Fábio O; Almeida, Fábio C L; Terenzi, Hernán; Valente, Ana Paula

2008-09-01

The Herbaspirillum seropedicae genome sequence encodes a truncated hemoglobin typical of group II (Hs-trHb1) members of this family. We show that His-tagged recombinant Hs-trHb1 is monomeric in solution, and its optical spectrum resembles those of previously reported globins. NMR analysis allowed us to assign heme substituents. All data suggest that Hs-trHb1 undergoes a transition from an aquomet form in the ferric state to a hexacoordinate low-spin form in the ferrous state. The close positions of Ser-E7, Lys-E10, Tyr-B10, and His-CD1 in the distal pocket place them as candidates for heme coordination and ligand regulation. Peroxide degradation kinetics suggests an easy access to the heme pocket, as the protein offered no protection against peroxide degradation when compared with free heme. The high solvent exposure of the heme may be due to the presence of a flexible loop in the access pocket, as suggested by a structural model obtained by using homologous globins as templates. The truncated hemoglobin described here has unique features among truncated hemoglobins and may function in the facilitation of O(2) transfer and scavenging, playing an important role in the nitrogen-fixation mechanism.

Truncation of a mannanase from Trichoderma harzianum improves its enzymatic properties and expression efficiency in Trichoderma reesei.

Science.gov (United States)

Wang, Juan; Zeng, Desheng; Liu, Gang; Wang, Shaowen; Yu, Shaowen

2014-01-01

To obtain high expression efficiency of a mannanase gene, ThMan5A, cloned from Trichoderma harzianum MGQ2, both the full-length gene and a truncated gene (ThMan5AΔCBM) that contains only the catalytic domain, were expressed in Trichoderma reesei QM9414 using the strong constitutive promoter of the gene encoding pyruvate decarboxylase (pdc), and purified to homogeneity, respectively. We found that truncation of the gene improved its expression efficiency as well as the enzymatic properties of the encoded protein. The recombinant strain expressing ThMan5AΔCBM produced 2,460 ± 45.1 U/ml of mannanase activity in the culture supernatant; 2.3-fold higher than when expressing the full-length ThMan5A gene. In addition, the truncated mannanase had superior thermostability compared with the full-length enzyme and retained 100 % of its activity after incubation at 60 °C for 48 h. Our results clearly show that the truncated ThMan5A enzyme exhibited improved characteristics both in expression efficiency and in its thermal stability. These characteristics suggest that ThMan5AΔCBM has potential applications in the food, feed, paper, and pulp industries.

Prognostic Value of Electrocardiographic Left Ventricular Hypertrophy on Cardiovascular Risk in a Non-hypertensive Community-based Population.

Science.gov (United States)

Tanaka, Kentaro; Tanaka, Fumitaka; Onoda, Toshiyuki; Tanno, Kozo; Ohsawa, Masaki; Sakata, Kiyomi; Omama, Shinichi; Ogasawara, Kuniaki; Ishibashi, Yasuhiro; Itai, Kazuyoshi; Kuribayashi, Toru; Okayama, Akira; Nakamura, Motoyuki

2018-04-06

The appearance of left ventricular hypertrophy on 12-lead electrocardiography (ECG-LVH) has been clarified to be associated with the risk of incidence of cardiovascular events (CVEs) in hypertensive individuals and the general population, but not enough in non-hypertensive individuals. A total of 4,927 non-hypertensive individuals ≥ 40 years of age who were free of CVE in the general population were followed for the incidence of CVE. ECG-LVH was defined according to criteria of the Sokolow-Lyon (SL) voltage, Cornell voltage (CV), or Cornell voltage product (CP). During the average 9.8 ± 2.0 years of follow-up, 267 individuals (5.4%) had their first CVE. The hazard ratio (HR) for the incidence of CVE after full adjustment by potential confounders significantly increased in the individuals with ECG-LVH by any criteria of the SL voltage, CV, and CP (HR = 1.77, p < 0.001) compared to those with no ECG-LVH. This association was significant also in individuals without any of obesity, dyslipidemia, and diabetes mellitus or those with systolic BP <120 mmHg and diastolic BP < 80mmHg. Furthermore, ECG-LVH by each criteria provided the reclassification improvement for the CVE risk prediction model by the Framingham 10-year risk score (the net reclassification improvement = 0.17 to 0.22, each p value < 0.010). In the absence of hypertension, ECG-LVH parameters are associated with the increased risk of developed CVEs independent of the established risk factors and provide the additional prognostic value in an assessment of the CVE risk using the traditional risk factors.

Firewalls as artefacts of inconsistent truncations of quantum geometries

Energy Technology Data Exchange (ETDEWEB)

Germani, Cristiano [Max-Planck-Institut fuer Physik, Muenchen (Germany); Arnold Sommerfeld Center, Ludwig-Maximilians-University, Muenchen (Germany); Institut de Ciencies del Cosmos, Universitat de Barcelona (Spain); Sarkar, Debajyoti [Max-Planck-Institut fuer Physik, Muenchen (Germany); Arnold Sommerfeld Center, Ludwig-Maximilians-University, Muenchen (Germany)

2016-01-15

In this paper we argue that a firewall is simply a manifestation of an inconsistent truncation of non-perturbative effects that unitarize the semiclassical black hole. Namely, we show that a naive truncation of quantum corrections to the Hawking spectrum at order O(e{sup -S}), inexorably leads to a ''localised'' divergent energy density near the black hole horizon. Nevertheless, in the same approximation, a distant observer only sees a discretised spectrum and concludes that unitarity is achieved by (e{sup -S}) effects. This is due to the fact that instead, the correct quantum corrections to the Hawking spectrum go like (g{sup tt}e{sup -S}). Therefore, while at a distance far away from the horizon, where g{sup tt} ∼ 1, quantum corrections are perturbative, they do diverge close to the horizon, where g{sup tt} → ∞. Nevertheless, these ''corrections'' nicely re-sum so that correlations functions are smooth at the would-be black hole horizon. Thus, we conclude that the appearance of firewalls is just a signal of the breaking of the semiclassical approximation at the Page time, even for large black holes. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Firewalls as artefacts of inconsistent truncations of quantum geometries

International Nuclear Information System (INIS)

Germani, Cristiano; Sarkar, Debajyoti

2016-01-01

In this paper we argue that a firewall is simply a manifestation of an inconsistent truncation of non-perturbative effects that unitarize the semiclassical black hole. Namely, we show that a naive truncation of quantum corrections to the Hawking spectrum at order O(e -S ), inexorably leads to a ''localised'' divergent energy density near the black hole horizon. Nevertheless, in the same approximation, a distant observer only sees a discretised spectrum and concludes that unitarity is achieved by (e -S ) effects. This is due to the fact that instead, the correct quantum corrections to the Hawking spectrum go like (g tt e -S ). Therefore, while at a distance far away from the horizon, where g tt ∼ 1, quantum corrections are perturbative, they do diverge close to the horizon, where g tt → ∞. Nevertheless, these ''corrections'' nicely re-sum so that correlations functions are smooth at the would-be black hole horizon. Thus, we conclude that the appearance of firewalls is just a signal of the breaking of the semiclassical approximation at the Page time, even for large black holes. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Maltose binding protein-fusion enhances the bioactivity of truncated forms of pig myostatin propeptide produced in E. coli.

Directory of Open Access Journals (Sweden)

Sang Beum Lee

Full Text Available Myostatin (MSTN is a potent negative regulator of skeletal muscle growth. MSTN propeptide (MSTNpro inhibits MSTN binding to its receptor through complex formation with MSTN, implying that MSTNpro can be a useful agent to improve skeletal muscle growth in meat-producing animals. Four different truncated forms of pig MSTNpro containing N-terminal maltose binding protein (MBP as a fusion partner were expressed in E. coli, and purified by the combination of affinity chromatography and gel filtration. The MSTN-inhibitory capacities of these proteins were examined in an in vitro gene reporter assay. A MBP-fused, truncated MSTNpro containing residues 42-175 (MBP-Pro42-175 exhibited the same MSTN-inhibitory potency as the full sequence MSTNpro. Truncated MSTNpro proteins containing either residues 42-115 (MBP-Pro42-115 or 42-98 (MBP-Pro42-98 also exhibited MSTN-inhibitory capacity even though the potencies were significantly lower than that of full sequence MSTNpro. In pull-down assays, MBP-Pro42-175, MBP-Pro42-115, and MBP-Pro42-98 demonstrated their binding to MSTN. MBP was removed from the truncated MSTNpro proteins by incubation with factor Xa to examine the potential role of MBP on MSTN-inhibitory capacity of those proteins. Removal of MBP from MBP-Pro42-175 and MBP-Pro42-98 resulted in 20-fold decrease in MSTN-inhibitory capacity of Pro42-175 and abolition of MSTN-inhibitory capacity of Pro42-98, indicating that MBP as fusion partner enhanced the MSTN-inhibitory capacity of those truncated MSTNpro proteins. In summary, this study shows that MBP is a very useful fusion partner in enhancing MSTN-inhibitory potency of truncated forms of MSTNpro proteins, and MBP-fused pig MSTNpro consisting of amino acid residues 42-175 is sufficient to maintain the full MSTN-inhibitory capacity.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

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C.Y. Nishikawa

2012-02-01

Full Text Available Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ54 co-factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL. A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH4Cl but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

Energy Technology Data Exchange (ETDEWEB)

Nishikawa, C.Y.; Araújo, L.M.; Kadowaki, M.A.S.; Monteiro, R.A.; Steffens, M.B.R.; Pedrosa, F.O.; Souza, E.M.; Chubatsu, L.S. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil)

2012-01-27

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ{sup 54} factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH{sub 4}Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense.

Science.gov (United States)

Nishikawa, C Y; Araújo, L M; Kadowaki, M A S; Monteiro, R A; Steffens, M B R; Pedrosa, F O; Souza, E M; Chubatsu, L S

2012-02-01

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ(54) co-factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH(4)Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription.

Expression and characterization of an N-truncated form of the NifA protein of Azospirillum brasilense

International Nuclear Information System (INIS)

Nishikawa, C.Y.; Araújo, L.M.; Kadowaki, M.A.S.; Monteiro, R.A.; Steffens, M.B.R.; Pedrosa, F.O.; Souza, E.M.; Chubatsu, L.S.

2012-01-01

Azospirillum brasilense is a nitrogen-fixing bacterium associated with important agricultural crops such as rice, wheat and maize. The expression of genes responsible for nitrogen fixation (nif genes) in this bacterium is dependent on the transcriptional activator NifA. This protein contains three structural domains: the N-terminal domain is responsible for the negative control by fixed nitrogen; the central domain interacts with the RNA polymerase σ 54 factor and the C-terminal domain is involved in DNA binding. The central and C-terminal domains are linked by the interdomain linker (IDL). A conserved four-cysteine motif encompassing the end of the central domain and the IDL is probably involved in the oxygen-sensitivity of NifA. In the present study, we have expressed, purified and characterized an N-truncated form of A. brasilense NifA. The protein expression was carried out in Escherichia coli and the N-truncated NifA protein was purified by chromatography using an affinity metal-chelating resin followed by a heparin-bound resin. Protein homogeneity was determined by densitometric analysis. The N-truncated protein activated in vivo nifH::lacZ transcription regardless of fixed nitrogen concentration (absence or presence of 20 mM NH 4 Cl) but only under low oxygen levels. On the other hand, the aerobically purified N-truncated NifA protein bound to the nifB promoter, as demonstrated by an electrophoretic mobility shift assay, implying that DNA-binding activity is not strictly controlled by oxygen levels. Our data show that, while the N-truncated NifA is inactive in vivo under aerobic conditions, it still retains DNA-binding activity, suggesting that the oxidized form of NifA bound to DNA is not competent to activate transcription

Detecting and correcting for publication bias in meta-analysis - A truncated normal distribution approach.

Science.gov (United States)

Zhu, Qiaohao; Carriere, K C

2016-01-01

Publication bias can significantly limit the validity of meta-analysis when trying to draw conclusion about a research question from independent studies. Most research on detection and correction for publication bias in meta-analysis focus mainly on funnel plot-based methodologies or selection models. In this paper, we formulate publication bias as a truncated distribution problem, and propose new parametric solutions. We develop methodologies of estimating the underlying overall effect size and the severity of publication bias. We distinguish the two major situations, in which publication bias may be induced by: (1) small effect size or (2) large p-value. We consider both fixed and random effects models, and derive estimators for the overall mean and the truncation proportion. These estimators will be obtained using maximum likelihood estimation and method of moments under fixed- and random-effects models, respectively. We carried out extensive simulation studies to evaluate the performance of our methodology, and to compare with the non-parametric Trim and Fill method based on funnel plot. We find that our methods based on truncated normal distribution perform consistently well, both in detecting and correcting publication bias under various situations.

Organisation and melting of solution grown truncated lozenge polyethylene single crystals

NARCIS (Netherlands)

Loos, J.; Tian, M.

2003-01-01

Morphological features and the melting behaviour of truncated lozenge crystals have been studied. For the crystals investigated, the heights of the (110) and the (200) sectors were measured to be 14.5 and 12.7 nm, respectively, using atomic force microscopy (AFM) in contact and non-contact mode.

Truncated SALL1 Impedes Primary Cilia Function in Townes-Brocks Syndrome

DEFF Research Database (Denmark)

Bozal-Basterra, Laura; Martín-Ruíz, Itziar; Pirone, Lucia

2018-01-01

by mutations in the gene encoding the transcriptional repressor SALL1 and is associated with the presence of a truncated protein that localizes to the cytoplasm. Here, we provide evidence that SALL1 mutations might cause TBS by means beyond its transcriptional capacity. By using proximity proteomics, we show...

Efficient Tridiagonal Preconditioner for the Matrix-Free Truncated Newton Method

Czech Academy of Sciences Publication Activity Database

Lukšan, Ladislav; Vlček, Jan

2014-01-01

Roč. 235, 25 May (2014), s. 394-407 ISSN 0096-3003 R&D Projects: GA ČR GA13-06684S Institutional support: RVO:67985807 Keywords : unconstrained optimization * large scale optimization * matrix-free truncated Newton method * preconditioned conjugate gradient method * preconditioners obtained by the directional differentiation * numerical algorithms Subject RIV: BA - General Mathematics Impact factor: 1.551, year: 2014

Foucault's Flirt? Neoliberalism, the Left and the Welfare State

DEFF Research Database (Denmark)

Hansen, Magnus Paulsen

2015-01-01

An essay on the review of works interpreting the lectures of Michel Foucault on neoliberalism is presented. It offers a history of neoliberalism as a way to reinvent the left and examines the way Foucault betrayed the left while resisting to be connected with a normative political programme...... or principle for a neoliberal stance. The author relates the risks in neoliberal thought for losing what is specific in definitive statements and the loss of neoliberal thought coherence within a reality....

Family losses following truncation selection in populations of half-sib families

Science.gov (United States)

J. H. Roberds; G. Namkoong; H. Kang

1980-01-01

Family losses during truncation selection may be sizable in populations of half-sib families. Substantial losses may occur even in populations containing little or no variation among families. Heavier losses will occur, however, under conditions of high heritability where there is considerable family variation. Standard deviations and therefore variances of family loss...

'He left me a message on Facebook': comparing the risk profiles of self-harming patients who leave paper suicide notes with those who leave messages on new media.

Science.gov (United States)

Barrett, Jessica R; Shetty, Hitesh; Broadbent, Matthew; Cross, Sean; Hotopf, Matthew; Stewart, Robert; Lee, William

2016-05-01

In cases of non-fatal self-harm, suicide notes are a major risk factor for repeated self-harm and suicide. Suicide notes can now be left on new media services, emails or text messages, as well as on paper. In a group of people who had harmed themselves, we aimed to compare new media note-leavers with paper note-leavers and characterise these groups demographically and by risk factors. Clinical notes of patients who presented with non-fatal self-harm to two London emergency departments were anonymously searched for mentions of new media use. These were categorised and risk factors were compared for those who had left a new media note, a paper note, or no note to establish differences in risk of note-leaving. New media note-leaving was associated with younger age and substance use; both risk factors for repeated self-harm. However, suicidal intent remained highest in paper note-leavers. Paper note-leavers remain at greatest risk, however new media note leaving is still correlated with risk factors related to repeated self-harm and suicide. Clinicians should enquire about new media use during emergency department assessments of self-harm. None. © The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

LGI2 truncation causes a remitting focal epilepsy in dogs.

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Eija H Seppälä

2011-07-01

Full Text Available One quadrillion synapses are laid in the first two years of postnatal construction of the human brain, which are then pruned until age 10 to 500 trillion synapses composing the final network. Genetic epilepsies are the most common neurological diseases with onset during pruning, affecting 0.5% of 2-10-year-old children, and these epilepsies are often characterized by spontaneous remission. We previously described a remitting epilepsy in the Lagotto romagnolo canine breed. Here, we identify the gene defect and affected neurochemical pathway. We reconstructed a large Lagotto pedigree of around 34 affected animals. Using genome-wide association in 11 discordant sib-pairs from this pedigree, we mapped the disease locus to a 1.7 Mb region of homozygosity in chromosome 3 where we identified a protein-truncating mutation in the Lgi2 gene, a homologue of the human epilepsy gene LGI1. We show that LGI2, like LGI1, is neuronally secreted and acts on metalloproteinase-lacking members of the ADAM family of neuronal receptors, which function in synapse remodeling, and that LGI2 truncation, like LGI1 truncations, prevents secretion and ADAM interaction. The resulting epilepsy onsets at around seven weeks (equivalent to human two years, and remits by four months (human eight years, versus onset after age eight in the majority of human patients with LGI1 mutations. Finally, we show that Lgi2 is expressed highly in the immediate post-natal period until halfway through pruning, unlike Lgi1, which is expressed in the latter part of pruning and beyond. LGI2 acts at least in part through the same ADAM receptors as LGI1, but earlier, ensuring electrical stability (absence of epilepsy during pruning years, preceding this same function performed by LGI1 in later years. LGI2 should be considered a candidate gene for common remitting childhood epilepsies, and LGI2-to-LGI1 transition for mechanisms of childhood epilepsy remission.

A Novel Truncated Form of Serum Amyloid A in Kawasaki Disease.

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John C Whitin

Full Text Available Kawasaki disease (KD is an acute vasculitis in children that can cause coronary artery abnormalities. Its diagnosis is challenging, and many cytokines, chemokines, acute phase reactants, and growth factors have failed evaluation as specific biomarkers to distinguish KD from other febrile illnesses. We performed protein profiling, comparing plasma from children with KD with febrile control (FC subjects to determine if there were specific proteins or peptides that could distinguish the two clinical states.Plasma from three independent cohorts from the blood of 68 KD and 61 FC subjects was fractionated by anion exchange chromatography, followed by surface-enhanced laser desorption ionization (SELDI mass spectrometry of the fractions. The mass spectra of KD and FC plasma samples were analyzed for peaks that were statistically significantly different.A mass spectrometry peak with a mass of 7,860 Da had high intensity in acute KD subjects compared to subacute KD (p = 0.0003 and FC (p = 7.9 x 10-10 subjects. We identified this peak as a novel truncated form of serum amyloid A with N-terminal at Lys-34 of the circulating form and validated its identity using a hybrid mass spectrum immunoassay technique. The truncated form of serum amyloid A was present in plasma of KD subjects when blood was collected in tubes containing protease inhibitors. This peak disappeared when the patients were examined after their symptoms resolved. Intensities of this peptide did not correlate with KD-associated laboratory values or with other mass spectrum peaks from the plasma of these KD subjects.Using SELDI mass spectrometry, we have discovered a novel truncated form of serum amyloid A that is elevated in the plasma of KD when compared with FC subjects. Future studies will evaluate its relevance as a diagnostic biomarker and its potential role in the pathophysiology of KD.

A computational approach for fluid queues driven by truncated birth-death processes.

NARCIS (Netherlands)

Lenin, R.B.; Parthasarathy, P.R.

2000-01-01

In this paper, we analyze fluid queues driven by truncated birth-death processes with general birth and death rates. We compute the equilibrium distribution of the content of the fluid buffer by providing efficient numerical procedures to compute the eigenvalues and the eigenvectors of the

A truncated Kv1.1 protein in the brain of the megencephaly mouse: expression and interaction

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Århem Peter

2005-11-01

Full Text Available Abstract Background The megencephaly mouse, mceph/mceph, is epileptic and displays a dramatically increased brain volume and neuronal count. The responsible mutation was recently revealed to be an eleven base pair deletion, leading to a frame shift, in the gene encoding the potassium channel Kv1.1. The predicted MCEPH protein is truncated at amino acid 230 out of 495. Truncated proteins are usually not expressed since nonsense mRNAs are most often degraded. However, high Kv1.1 mRNA levels in mceph/mceph brain indicated that it escaped this control mechanism. Therefore, we hypothesized that the truncated Kv1.1 would be expressed and dysregulate other Kv1 subunits in the mceph/mceph mice. Results We found that the MCEPH protein is expressed in the brain of mceph/mceph mice. MCEPH was found to lack mature (Golgi glycosylation, but to be core glycosylated and trapped in the endoplasmic reticulum (ER. Interactions between MCEPH and other Kv1 subunits were studied in cell culture, Xenopus oocytes and the brain. MCEPH can form tetramers with Kv1.1 in cell culture and has a dominant negative effect on Kv1.2 and Kv1.3 currents in oocytes. However, it does not retain Kv1.2 in the ER of neurons. Conclusion The megencephaly mice express a truncated Kv1.1 in the brain, and constitute a unique tool to study Kv1.1 trafficking relevant for understanding epilepsy, ataxia and pathologic brain overgrowth.

Non-linear buckling of an FGM truncated conical shell surrounded by an elastic medium

International Nuclear Information System (INIS)

Sofiyev, A.H.; Kuruoglu, N.

2013-01-01

In this paper, the non-linear buckling of the truncated conical shell made of functionally graded materials (FGMs) surrounded by an elastic medium has been studied using the large deformation theory with von Karman–Donnell-type of kinematic non-linearity. A two-parameter foundation model (Pasternak-type) is used to describe the shell–foundation interaction. The FGM properties are assumed to vary continuously through the thickness direction. The fundamental relations, the modified Donnell type non-linear stability and compatibility equations of the FGM truncated conical shell resting on the Pasternak-type elastic foundation are derived. By using the Superposition and Galerkin methods, the non-linear stability equations for the FGM truncated conical shell is solved. Finally, influences of variations of Winkler foundation stiffness and shear subgrade modulus of the foundation, compositional profiles and shell characteristics on the dimensionless critical non-linear axial load are investigated. The present results are compared with the available data for a special case. -- Highlights: • Nonlinear buckling of FGM conical shell surrounded by elastic medium is studied. • Pasternak foundation model is used to describe the shell–foundation interaction. • Nonlinear basic equations are derived. • Problem is solved by using Superposition and Galerkin methods. • Influences of various parameters on the nonlinear critical load are investigated

Selective translational repression of truncated proteins from frameshift mutation-derived mRNAs in tumors.

Directory of Open Access Journals (Sweden)

Kwon Tae You

2007-05-01

Full Text Available Frameshift and nonsense mutations are common in tumors with microsatellite instability, and mRNAs from these mutated genes have premature termination codons (PTCs. Abnormal mRNAs containing PTCs are normally degraded by the nonsense-mediated mRNA decay (NMD system. However, PTCs located within 50-55 nucleotides of the last exon-exon junction are not recognized by NMD (NMD-irrelevant, and some PTC-containing mRNAs can escape from the NMD system (NMD-escape. We investigated protein expression from NMD-irrelevant and NMD-escape PTC-containing mRNAs by Western blotting and transfection assays. We demonstrated that transfection of NMD-irrelevant PTC-containing genomic DNA of MARCKS generates truncated protein. In contrast, NMD-escape PTC-containing versions of hMSH3 and TGFBR2 generate normal levels of mRNA, but do not generate detectable levels of protein. Transfection of NMD-escape mutant TGFBR2 genomic DNA failed to generate expression of truncated proteins, whereas transfection of wild-type TGFBR2 genomic DNA or mutant PTC-containing TGFBR2 cDNA generated expression of wild-type protein and truncated protein, respectively. Our findings suggest a novel mechanism of gene expression regulation for PTC-containing mRNAs in which the deleterious transcripts are regulated either by NMD or translational repression.

Chaos and noise in a truncated Toda potential

International Nuclear Information System (INIS)

Habib, S.; Kandrup, H.E.; Mahon, M.E.

1996-01-01

Results are reported from a numerical investigation of orbits in a truncated Toda potential that is perturbed by weak friction and noise. Aside from the perturbations displaying a simple scaling in the amplitude of the friction and noise, it is found that even very weak friction and noise can induce an extrinsic diffusion through cantori on a time scale that is much shorter than that associated with intrinsic diffusion in the unperturbed system. The results have applications in galactic dynamics and in the formation of a beam halo in charged particle beams. copyright 1996 The American Physical Society

Novel nonsurgical left ventricular assist device and system.

Science.gov (United States)

Misiri, Juna; DeSimone, Christopher V; Park, Soon J; Kushwaha, Sudhir S; Friedman, Paul A; Bruce, Charles J; Asirvatham, Samuel J

2013-01-01

Treatment options for advanced stages of congestive heart failure remain limited. Left ventricular assist devices (LVADs) have emerged as a means to support failing circulation. However, these devices are not without significant risk such as major open chest surgery. We utilized a novel approach for device placement at the aorto-left atria continuity as a site to create a conduit capable of accommodating a percutaneous LVAD system. We designed and developed an expandable nitinol based device for placement at this site to create a shunt between the LA and aorta. Our experiments support this anatomic location as an accessible and feasible site for accommodation of an entirely percutaneous LVAD. The novelty of this approach would bypass the left ventricle, and thereby minimize complications and morbidities associated with current LVAD placement. Copyright © 2013 Elsevier Inc. All rights reserved.

Percutaneous closure of the left atrial appendage with Watchman device: An option for patients with atrial fibrilation and high risk of bleeding with anticoagulation

Directory of Open Access Journals (Sweden)

Sénior, Juan

2015-07-01

Full Text Available Atrial fibrillation is the most common arrhythmia found in clinical practice, with a population prevalence of 1% to 2%. Anticoagulation remains a fundamental part of treatment for the prevention of cerebrovascular events (stroke, but it is contraindicated in approximately 20% of patients. We report a case of non-valvular atrial fibrillation with high-risk score for stroke, a history of intracerebral bleeding, and very high risk of bleeding with long-term anticoagulation. Percutaneous closure of the left atrial appendage with the Watchman device was performed successfully without complications.

On the truncation of the azimuthal mode spectrum of high-order probes in probe-corrected spherical near-field antenna measurements

DEFF Research Database (Denmark)

Pivnenko, Sergey; Laitinen, Tommi

2011-01-01

Azimuthal mode (m mode) truncation of a high-order probe pattern in probe-corrected spherical near-field antenna measurements is studied in this paper. The results of this paper provide rules for appropriate and sufficient m-mode truncation for non-ideal first-order probes and odd-order probes wi...

Modified truncated randomized singular value decomposition (MTRSVD) algorithms for large scale discrete ill-posed problems with general-form regularization

Science.gov (United States)

Jia, Zhongxiao; Yang, Yanfei

2018-05-01

In this paper, we propose new randomization based algorithms for large scale linear discrete ill-posed problems with general-form regularization: subject to , where L is a regularization matrix. Our algorithms are inspired by the modified truncated singular value decomposition (MTSVD) method, which suits only for small to medium scale problems, and randomized SVD (RSVD) algorithms that generate good low rank approximations to A. We use rank-k truncated randomized SVD (TRSVD) approximations to A by truncating the rank- RSVD approximations to A, where q is an oversampling parameter. The resulting algorithms are called modified TRSVD (MTRSVD) methods. At every step, we use the LSQR algorithm to solve the resulting inner least squares problem, which is proved to become better conditioned as k increases so that LSQR converges faster. We present sharp bounds for the approximation accuracy of the RSVDs and TRSVDs for severely, moderately and mildly ill-posed problems, and substantially improve a known basic bound for TRSVD approximations. We prove how to choose the stopping tolerance for LSQR in order to guarantee that the computed and exact best regularized solutions have the same accuracy. Numerical experiments illustrate that the best regularized solutions by MTRSVD are as accurate as the ones by the truncated generalized singular value decomposition (TGSVD) algorithm, and at least as accurate as those by some existing truncated randomized generalized singular value decomposition (TRGSVD) algorithms. This work was supported in part by the National Science Foundation of China (Nos. 11771249 and 11371219).

Virtues and limitations of the truncated Holstein–Primakoff description of quantum rotors

International Nuclear Information System (INIS)

Hirsch, Jorge G; Castaños, Octavio; López-Peña, Ramón; Nahmad-Achar, Eduardo

2013-01-01

A Hamiltonian describing the collective behaviour of N interacting spins can be mapped to a bosonic one employing the Holstein–Primakoff realization, at the expense of having an infinite series in powers of the boson creation and annihilation operators. Truncating this series up to quadratic terms allows obtaining analytic solutions through a Bogoliubov transformation, which becomes exact in the limit N → ∞. The Hamiltonian exhibits a phase transition from single-spin excitations to a collective mode. In the vicinity of this phase transition, the truncated solutions predict the existence of singularities for a finite number of spins, which have no counterpart in the exact diagonalization. Renormalization allows to extract from these divergences the exact behaviour of relevant observables with the number of spins around the phase transition, and to relate it with the class of universality to which the model belongs. In this work a detailed analysis of these aspects is presented for the Lipkin model. (comment)

Heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.

Science.gov (United States)

Patel, Kashyap A; Kettunen, Jarno; Laakso, Markku; Stančáková, Alena; Laver, Thomas W; Colclough, Kevin; Johnson, Matthew B; Abramowicz, Marc; Groop, Leif; Miettinen, Päivi J; Shepherd, Maggie H; Flanagan, Sarah E; Ellard, Sian; Inagaki, Nobuya; Hattersley, Andrew T; Tuomi, Tiinamaija; Cnop, Miriam; Weedon, Michael N

2017-10-12

Finding new causes of monogenic diabetes helps understand glycaemic regulation in humans. To find novel genetic causes of maturity-onset diabetes of the young (MODY), we sequenced MODY cases with unknown aetiology and compared variant frequencies to large public databases. From 36 European patients, we identify two probands with novel RFX6 heterozygous nonsense variants. RFX6 protein truncating variants are enriched in the MODY discovery cohort compared to the European control population within ExAC (odds ratio = 131, P = 1 × 10 -4 ). We find similar results in non-Finnish European (n = 348, odds ratio = 43, P = 5 × 10 -5 ) and Finnish (n = 80, odds ratio = 22, P = 1 × 10 -6 ) replication cohorts. RFX6 heterozygotes have reduced penetrance of diabetes compared to common HNF1A and HNF4A-MODY mutations (27, 70 and 55% at 25 years of age, respectively). The hyperglycaemia results from beta-cell dysfunction and is associated with lower fasting and stimulated gastric inhibitory polypeptide (GIP) levels. Our study demonstrates that heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.Maturity-onset diabetes of the young (MODY) is the most common subtype of familial diabetes. Here, Patel et al. use targeted DNA sequencing of MODY patients and large-scale publically available data to show that RFX6 heterozygous protein truncating variants cause reduced penetrance MODY.

A truncated conical beam model for analysis of the vibration of rat whiskers.

Science.gov (United States)

Yan, Wenyi; Kan, Qianhua; Kergrene, Kenan; Kang, Guozheng; Feng, Xi-Qiao; Rajan, Ramesh

2013-08-09

A truncated conical beam model is developed to study the vibration behaviour of a rat whisker. Translational and rotational springs are introduced to better represent the constraint conditions at the base of the whiskers in a living rat. Dimensional analysis shows that the natural frequency of a truncated conical beam with generic spring constraints at its ends is inversely proportional to the square root of the mass density. Under all the combinations of the classical free, pinned, sliding or fixed boundary conditions of a truncated conical beam, it is proved that the natural frequency can be expressed as f = α(rb/L(2))E/ρ and the frequency coefficient α only depends on the ratio of the radii at the two ends of the beam. The natural frequencies of a representative rat whisker are predicted for two typical situations: freely whisking in air and the tip touching an object. Our numerical results show that there exists a window where the natural frequencies of a rat whisker are very sensitive to the change of the rotational constraint at the base. This finding is also confirmed by the numerical results of 18 whiskers with their data available from literature. It can be concluded that the natural frequencies of a rat whisker can be adjusted within a wide range through manipulating the constraints of the follicle on the rat base by a behaving animal. Copyright © 2013 Elsevier Ltd. All rights reserved.

Left-main restenosis in the DES era-a call for action.

Science.gov (United States)

di Palma, Gaetano; Cortese, Bernardo

2017-11-10

Percutaneous treatment of the unprotected left main trunk (ULM), defined as a vessel without patent bypass graft either to the left circumflex (LCX) or left anterior descending (LAD) artery, has gained a precise role thanks to recent scientific evidence. Although new generation drug-eluting stents have already proven to be safer, there is still a consistent risk of restenosis and late adverse events. The optimal management of a ULM restenosis is still debated. Here we aim at presenting a review of the available data in literature and show our choice for treating it. Copyright © 2017 Elsevier Inc. All rights reserved.

Size of Left Cardiac Chambers Correlates with Cerebral Microembolic Load in Open Heart Operations

Directory of Open Access Journals (Sweden)

Elena Z. Golukhova

2010-01-01

Full Text Available Background. Microemboli are a widely recognized etiological factor of cerebral complications in cardiac surgery patients. The present study was aimed to determine if size of left cardiac chambers relates to cerebral microembolic load in open heart operations. Methods. Thirty patients participated in the study. Echocardiography was performed in 2-3 days before surgery. A transcranial Doppler system was used for registering intraoperative microemboli. Results. Preoperative left atrium and left ventricular end-systolic and end-diastolic sizes significantly correlated with intraoperative microembolic load (s=0.48, 0.57 and 0.53, s≺.01, resp.. The associations between left ventricular diameters and number of cerebral microemboli remained significant when cardiopulmonary bypass time was included as a covariate into the analysis. Conclusions. The present results demonstrate that increased size of left heart chambers is an influential risk factor for elevated cerebral microembolic load during open heart operations. Mini-invasive surgery and carbon dioxide insufflation into wound cavity may be considered as neuroprotective approaches in patients with high risk of cerebral microembolism.

An elusive persistent left superior vena cava draining into left atrium

NARCIS (Netherlands)

A. Soward; F.J. ten Cate (Folkert); P.M. Fioretti (Paolo); P.W.J.C. Serruys (Patrick); J.R.T.C. Roelandt (Jos)

1986-01-01

textabstractA case report of a persistent left superior vena cava draining into left atrium with a fibromuscular left ventricular outflow tract obstruction and a small atrial septal defect. The anomalous vessel escaped detection during two right and left heart catheterizations from the right arm and

Expression and characterization of a novel truncated rotavirus VP4 for the development of a recombinant rotavirus vaccine.

Science.gov (United States)

Li, Yijian; Xue, Miaoge; Yu, Linqi; Luo, Guoxing; Yang, Han; Jia, Lianzhi; Zeng, Yuanjun; Li, Tingdong; Ge, Shengxiang; Xia, Ningshao

2018-04-12

The outer capsid protein VP4 is an important target for the development of a recombinant rotavirus vaccine because it mediates the attachment and penetration of rotavirus. Due to the poor solubility of full-length VP4, VP8 was explored as candidate rotavirus vaccines in the past years. In previous studies, it has been found that the N-terminal truncated VP8 protein, VP8-1 (aa26-231), could be expressed in soluble form with improved immunogenicity compared to the core of VP8 (aa65-223). However, this protein stimulated only a weak immune response when aluminum hydroxide was used as an adjuvant. In addition, it should be noted that the protective efficacy of VP4 was higher than that of VP8 and VP5. In this study, it was found that when the N-terminal 25 amino acids were deleted, the truncated VP4 ∗ (aa26-476) containing VP8 and the stalk domain of VP5 could be expressed in soluble form in E. coli and purified to homogeneous trimers. Furthermore, the truncated VP4 could induce high titers of neutralizing antibodies when aluminum adjuvant was used and conferred high protective efficacy in reducing the severity of diarrhea and rotavirus shedding in stools in animal models. The immunogenicity of the truncated VP4 was significantly higher than that of VP8 ∗ and VP5 ∗ alone. Taken together, the truncated VP4 ∗ (aa26-476), with enhanced immunogenicity and immunoprotectivity, could be considered as a viable candidate for further development and has the potential to become a parenterally administered rotavirus vaccine. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identification and purification of truncated insulin-like growth factor I from porcine uterus. Evidence for high biological potency

International Nuclear Information System (INIS)

Ogasawara, M.; Karey, K.P.; Marquardt, H.; Sirbasku, D.A.

1989-01-01

The authors report the completion of the purification of uterine-derived growth factors (UDGF) described previously by this laboratory. During isolation, the mitogenic activity was monitored by using the human MCF-7 breast cancer cells in serum-free Ham's F12 and Dulbecco's modified Eagle's medium (1:1, v/v) containing 15 mM 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 200 μg/mL bovine serum albumin, and 10 μg/mL human transferrin. This medium sustained growth for several days in response to a single addition of growth factor. The mitogens were shown by protein microsequencing to be DES 1 → 3 to DES 1 → 6 forms of insulin-like growth factor I (truncated IGF-I). An M r estimated by 125 I labeling, urea-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and autoradiography was consistent with a DES 1 → 3(4) N α truncation. Immunoadsorption and radioimmunoassay confirmed immunological properties equivalent to IGF-I. Radioreceptor assays showed truncated IGF-I was functionally equivalent to recombinant IGF-I. They conclude that the major acid-stable low-M r mitogenic activities isolated from uterus are very potent forms of truncated IGF-I capable of stimulating growth of epithelial and mesenchymal cells

Alcoholic liver cirrhosis increases the risk of left ventricular diastolic dysfunction

Czech Academy of Sciences Publication Activity Database

Brotánek, J.; Ort, Michael; Kubánek, M.; Stiborová, M.

2013-01-01

Roč. 34, Suppl.2 (2013), s. 64-70 ISSN 0172-780X R&D Projects: GA MŠk(CZ) 1M0517 Institutional research plan: CEZ:AV0Z50110509 Keywords : left ventricular diastolic dysfunction * cirrhosis * liver * alcohol Subject RIV: FH - Neurology Impact factor: 0.935, year: 2013

Use of the negative binomial-truncated Poisson distribution in thunderstorm prediction

Science.gov (United States)

Cohen, A. C.

1971-01-01

A probability model is presented for the distribution of thunderstorms over a small area given that thunderstorm events (1 or more thunderstorms) are occurring over a larger area. The model incorporates the negative binomial and truncated Poisson distributions. Probability tables for Cape Kennedy for spring, summer, and fall months and seasons are presented. The computer program used to compute these probabilities is appended.

Left ventricular mass in male adolescent athletes and non-athletes

Directory of Open Access Journals (Sweden)

Erling David Kaunang

2014-10-01

Full Text Available Background Systematic exercise leads to increased left ventricular mass, which may be misleading in a differential diagnosis of heart disease in athletes (physiologic hypertrophy versus pathologic hypertrophy. T he cause of left ventricular hypertrophy is an important risk factor in the morbidity and mortality of cardiovascular diseases. Objective To compare left ventricular mass and left ventricular hypertrophy in male adolescent athletes and non-athletes. Methods We conducted a cross-sectional, analytic study, from September to December 2012 in male adolescents aged 15-18 years. The case group included athletes from the Bina Taruna Football Club Manado, while the control group included non-athlete adolescents. All subjects underwent history-taking, physical examinations and further supporting examinations. Left ventricular mass was measured by cardiovascular echocardiography (Esaote Mylab 4.0 and calculated based on a formula. Left ventricular hypertrophy was defined as left ventricular mass of > 134 g/m2 body surface area. Results Subjects' mean left ventricular masses were 359.69 (SD 188.4; 95%CI 283.58 to 435.81 grams in the athlete group and 173.04 (SD 50.69; 95%CI 152.56 to 103.51 grams in the non· athlete group, a statistically significant difference (P=0.0001. Ventricular hypertrophy was found 76.9% compared to 11.5% in  the non-athlete group (P= 0.0001. Conclusion Left ventricular mass in athletes is bigger than in non-athletes. In addition, left ventricular hypertrophy is more cornmon in male adolescent athletes than in non-athletes.

Impact of left ventricular geometry on prognosis in hypertensive patients with left ventricular hypertrophy (the LIFE study)

DEFF Research Database (Denmark)

Gerdts, E.; Cramariuc, D.; Simone, G. de

2008-01-01

, and myocardial infarction) in 937 hypertensive patients with LV hypertrophy during 4.8 years losartan- or atenolol-based treatment in the Losartan Intervention for Endpoint reduction in hypertension (LIFE) echocardiography substudy. METHODS AND RESULTS: LV geometry was determined from LV mass/body surface area......AIMS: Less is known about the relation between in-treatment left ventricular (LV) geometry and risk of cardiovascular events. We assessed LV geometric patterns on baseline and annual echocardiograms as time-varying predictors of the primary composite endpoint (cardiovascular death, stroke...... including LV geometric patterns as time-varying variables and adjusting for treatment, Framingham risk score, race, and time-varying systolic blood pressure, the patterns independently predicted higher risk of primary composite endpoints [HR 2.99 (1.16-7.71) for concentric remodelling, HR 1.79 (1...

Risk of brain injury during diagnostic coronary angiography: comparison between right and left radial approach.

Science.gov (United States)

Pacchioni, Andrea; Versaci, Francesco; Mugnolo, Antonio; Penzo, Carlo; Nikas, Dimitrios; Saccà, Salvatore; Favero, Luca; Agostoni, Pier Francesco; Garami, Zsolt; Prati, Francesco; Reimers, Bernhard

2013-09-10

To assess the incidence of silent cerebral embolization when using the transradial approach for diagnostic coronary angiography (DCA). Compared to other vascular access sites, the right transradial approach (RTA) could reduce the amount of brain emboli by avoiding mechanical trauma to the aortic wall caused by catheters and wire, whereas it increases manipulation of catheters in the ascending aorta and has a higher risk of direct embolization into the right common carotid artery. A recent study showed an increased incidence of microembolic signals (MES) in RTA compared to femoral. However, left transradial approach (LTA) has never been assessed. 40 patients with suspected coronary artery disease were randomized to DCA via RTA (n=20) or LTA (n=20) with contemporaneous bilateral transcranial Doppler monitoring. MES were detected in all patients, with a significantly higher rate in the RTA group (median 61, interquartile range (IQR) 47-105, vs 48, IQR 31-60, p=0.035). MES generated during procedures needing >2 catheters (n=8), are higher than those detected during procedures performed with 2 catheters (n=32, 102, IQR 70-108, vs 48, IQR 33-60, p=0.001). At multivariate analysis increasing number of catheters was the only independent predictor of high incidence of MES (OR 16.4, 95% CI 1.23-219.9, p=0.034, -2LL=26.7). LTA has a lower risk of brain embolization because of the lower number of catheter exchange maneuvers. Since the degree of brain embolism depends on the magnitude of mechanical manipulation, catheter changes should be minimized to reduce the risk of cerebral embolization. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

International Nuclear Information System (INIS)

Tang, Yanan; Li, Liang

2013-01-01

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. • 12 C 2 -Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released 12 C 2 -dansyl labeled N-terminal amino acid was quantified using 13 C 2 -dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards

Field of view extension and truncation correction for MR-based human attenuation correction in simultaneous MR/PET imaging

International Nuclear Information System (INIS)

Blumhagen, Jan O.; Ladebeck, Ralf; Fenchel, Matthias; Braun, Harald; Quick, Harald H.; Faul, David; Scheffler, Klaus

2014-01-01

Purpose: In quantitative PET imaging, it is critical to accurately measure and compensate for the attenuation of the photons absorbed in the tissue. While in PET/CT the linear attenuation coefficients can be easily determined from a low-dose CT-based transmission scan, in whole-body MR/PET the computation of the linear attenuation coefficients is based on the MR data. However, a constraint of the MR-based attenuation correction (AC) is the MR-inherent field-of-view (FoV) limitation due to static magnetic field (B 0 ) inhomogeneities and gradient nonlinearities. Therefore, the MR-based human AC map may be truncated or geometrically distorted toward the edges of the FoV and, consequently, the PET reconstruction with MR-based AC may be biased. This is especially of impact laterally where the patient arms rest beside the body and are not fully considered. Methods: A method is proposed to extend the MR FoV by determining an optimal readout gradient field which locally compensates B 0 inhomogeneities and gradient nonlinearities. This technique was used to reduce truncation in AC maps of 12 patients, and the impact on the PET quantification was analyzed and compared to truncated data without applying the FoV extension and additionally to an established approach of PET-based FoV extension. Results: The truncation artifacts in the MR-based AC maps were successfully reduced in all patients, and the mean body volume was thereby increased by 5.4%. In some cases large patient-dependent changes in SUV of up to 30% were observed in individual lesions when compared to the standard truncated attenuation map. Conclusions: The proposed technique successfully extends the MR FoV in MR-based attenuation correction and shows an improvement of PET quantification in whole-body MR/PET hybrid imaging. In comparison to the PET-based completion of the truncated body contour, the proposed method is also applicable to specialized PET tracers with little uptake in the arms and might reduce the

Quark-gluon vertex dressing and meson masses beyond ladder-rainbow truncation

International Nuclear Information System (INIS)

Matevosyan, Hrayr H.; Thomas, Anthony W.; Tandy, Peter C.

2007-01-01

We include a generalized infinite class of quark-gluon vertex dressing diagrams in a study of how dynamics beyond the ladder-rainbow truncation influences the Bethe-Salpeter description of light-quark pseudoscalar and vector mesons. The diagrammatic specification of the vertex is mapped into a corresponding specification of the Bethe-Salpeter kernel, which preserves chiral symmetry. This study adopts the algebraic format afforded by the simple interaction kernel used in previous work on this topic. The new feature of the present work is that in every diagram summed for the vertex and the corresponding Bethe-Salpeter kernel, each quark-gluon vertex is required to be the self-consistent vertex solution. We also adopt from previous work the effective accounting for the role of the explicitly non-Abelian three-gluon coupling in a global manner through one parameter determined from recent lattice-QCD data for the vertex. Within the current model, the more consistent dressed vertex limits the ladder-rainbow truncation error for vector mesons to be never more than 10% as the current quark mass is varied from the u/d region to the b region

Truncated exponential-rigid-rotor model for strong electron and ion rings

International Nuclear Information System (INIS)

Larrabee, D.A.; Lovelace, R.V.; Fleischmann, H.H.

1979-01-01

A comprehensive study of exponential-rigid-rotor equilibria for strong electron and ion rings indicates the presence of a sizeable percentage of untrapped particles in all equilibria with aspect-ratios R/a approximately <4. Such aspect-ratios are required in fusion-relevant rings. Significant changes in the equilibria are observed when untrapped particles are excluded by the use of a truncated exponential-rigid-rotor distribution function. (author)

Age-related left ventricular remodeling and associated risk for cardiovascular outcomes: the Multi-Ethnic Study of Atherosclerosis.

Science.gov (United States)

Cheng, Susan; Fernandes, Verônica R S; Bluemke, David A; McClelland, Robyn L; Kronmal, Richard A; Lima, João A C

2009-05-01

Age-related alterations of left ventricular (LV) structure and function that may predispose to cardiovascular events are not well understood. We used cardiac MRI to examine age-related differences in LV structure and function in 5004 participants without overt cardiovascular disease when enrolled in the Multi-Ethnic Study of Atherosclerosis; 1099 participants received additional strain analyses by MRI tagging. We also assessed the relation of age-associated remodeling with cardiovascular outcomes using Cox proportional hazard models adjusting for cardiovascular risk factors. Although LV mass decreased with age (-0.3 g per year), the mass-to-volume ratio markedly increased (+5 mg/mL per year, Pfall in stroke volume (-0.4 mL per year, P or =65 years; hazard ratio, 1.68 [CI 0.77 to 3.68]) individuals with the highest compared to lowest mass-to-volume ratio quintile (P(interaction)=0.013). Age is associated with a phenotype of LV remodeling marked by increased mass-to-volume ratio and accompanied by systolic as well as diastolic myocardial dysfunction that is not reflected by preserved ejection fraction. This pattern of ventricular remodeling confers significant cardiovascular risk, particularly when present earlier in life.

Integral equation solution for truncated slab structures by using a fringe current formulation

DEFF Research Database (Denmark)

Jørgensen, Erik; Toccafondi, A.; Maci, S.

1999-01-01

Full-wave solutions of truncated dielectric slab problems are interesting for a variety of engineering applications, in particular patch antennas on finite ground planes. For this application a canonical reference solution is that of a semi-infinite slab illuminated by a line source. Standard int...

Left ventricular hypertrophy in normoalbuminuric type 2 diabetic patients not taking antihypertensive treatment

DEFF Research Database (Denmark)

Sato, A; Tarnow, L; Nielsen, F S

2005-01-01

BACKGROUND: Left ventricular hypertrophy (LVH) is an independent risk factor for myocardial ischaemia, cardiac arrhythmia, sudden death, and heart failure, all common findings in patients with type 2 diabetes. AIM: To determine the prevalence of, and risk factors for, LVH in normoalbuminuric type 2...... diabetic patients not taking antihypertensive treatment. DESIGN: Cross-sectional study. METHODS: From 1994 to 1998, M-mode echocardiography was performed by one experienced examiner in 262 consecutive, normoalbuminuric Caucasian type 2 diabetic patients, all with blood pressure ... of diabetes and blood pressure were not. Similar results were obtained for left ventricular mass index. DISCUSSION: LVH was frequent in our normoalbuminuric type 2 diabetic patients not taking antihypertensive treatment. Several potentially modifiable risk factors, such as raised BMI, poor glycaemic control...

Simultaneous kissing stents for the treatment of left main stenosis in cardiogenic shock

International Nuclear Information System (INIS)

Rahman, N.; Dhakam, S.; Nadeem, N.

2007-01-01

Significant narrowing of the left main coronary artery puts the patient at high risk, since occlusion of this vessel, if unprotected by collateral flow or a patent bypass graft to either the left anterior descending or circumflex artery, compromises flow to approximately 75% of the left ventricle. Percutaneous coronary intervention of left main coronary artery may be the only life saving procedure. There are limited data on the general use of percutaneous intervention (PCI) in patients with acute myocardial infarction (MI) due to left main disease. Small series have noted in-hospital mortality rates of 30 to 35 percent following PCI with or without stenting. Moreover, cardiogenic shock secondary to acute MI, in patients with left main coronary artery disease, carries a very high mortality. Treatment options are limited especially when emergent coronary artery bypass surgery is not an option. We report a case of emergency angioplasty of left main coronary artery with simultaneous kissing stent technique in cardiogenic shock. (author)

Risk seeking for losses modulates the functional connectivity of the default mode and left frontoparietal networks in young males.

Science.gov (United States)

Deza Araujo, Yacila I; Nebe, Stephan; Neukam, Philipp T; Pooseh, Shakoor; Sebold, Miriam; Garbusow, Maria; Heinz, Andreas; Smolka, Michael N

2018-06-01

Value-based decision making (VBDM) is a principle that states that humans and other species adapt their behavior according to the dynamic subjective values of the chosen or unchosen options. The neural bases of this process have been extensively investigated using task-based fMRI and lesion studies. However, the growing field of resting-state functional connectivity (RSFC) may shed light on the organization and function of brain connections across different decision-making domains. With this aim, we used independent component analysis to study the brain network dynamics in a large cohort of young males (N = 145) and the relationship of these dynamics with VBDM. Participants completed a battery of behavioral tests that evaluated delay aversion, risk seeking for losses, risk aversion for gains, and loss aversion, followed by an RSFC scan session. We identified a set of large-scale brain networks and conducted our analysis only on the default mode network (DMN) and networks comprising cognitive control, appetitive-driven, and reward-processing regions. Higher risk seeking for losses was associated with increased connectivity between medial temporal regions, frontal regions, and the DMN. Higher risk seeking for losses was also associated with increased coupling between the left frontoparietal network and occipital cortices. These associations illustrate the participation of brain regions involved in prospective thinking, affective decision making, and visual processing in participants who are greater risk-seekers, and they demonstrate the sensitivity of RSFC to detect brain connectivity differences associated with distinct VBDM parameters.

Gender specific pattern of left ventricular cardiac adaptation to ...

African Journals Online (AJOL)

EB

2013-09-03

Sep 3, 2013 ... Some gender specific associations with left ventricular structure and function have been described ... used for analysis. ... risk due to LVH and that cardiac adaptation to ... had history taking, physical examination and ..... between the gender specific differences in cardiac ... A metaanalysis of individual.

The renormalized Hamiltonian truncation method in the large E{sub T} expansion

Energy Technology Data Exchange (ETDEWEB)

Elias-Miró, J. [SISSA and INFN, I-34136 Trieste (Italy); Montull, M. [Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology (BIST), Campus UAB, E-08193 Bellaterra (Spain); Riembau, M. [Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology (BIST), Campus UAB, E-08193 Bellaterra (Spain); DESY, Notkestrasse 85, 22607 Hamburg (Germany)

2016-04-22

Hamiltonian Truncation Methods are a useful numerical tool to study strongly coupled QFTs. In this work we present a new method to compute the exact corrections, at any order, in the Hamiltonian Truncation approach presented by Rychkov et al. in refs. http://dx.doi.org/10.1103/PhysRevD.91.085011; http://dx.doi.org/10.1103/PhysRevD.93.065014; http://dx.doi.org/10.1103/PhysRevD.91.025005. The method is general but as an example we calculate the exact g{sup 2} and some of the g{sup 3} contributions for the ϕ{sup 4} theory in two dimensions. The coefficients of the local expansion calculated in ref. http://dx.doi.org/10.1103/PhysRevD.91.085011 are shown to be given by phase space integrals. In addition we find new approximations to speed up the numerical calculations and implement them to compute the lowest energy levels at strong coupling. A simple diagrammatic representation of the corrections and various tests are also introduced.

PLK1 has tumor-suppressive potential in APC-truncated colon cancer cells.

Science.gov (United States)

Raab, Monika; Sanhaji, Mourad; Matthess, Yves; Hörlin, Albrecht; Lorenz, Ioana; Dötsch, Christina; Habbe, Nils; Waidmann, Oliver; Kurunci-Csacsko, Elisabeth; Firestein, Ron; Becker, Sven; Strebhardt, Klaus

2018-03-16

The spindle assembly checkpoint (SAC) acts as a molecular safeguard in ensuring faithful chromosome transmission during mitosis, which is regulated by a complex interplay between phosphatases and kinases including PLK1. Adenomatous polyposis coli (APC) germline mutations cause aneuploidy and are responsible for familial adenomatous polyposis (FAP). Here we study the role of PLK1 in colon cancer cells with chromosomal instability promoted by APC truncation (APC-ΔC). The expression of APC-ΔC in colon cells reduces the accumulation of mitotic cells upon PLK1 inhibition, accelerates mitotic exit and increases the survival of cells with enhanced chromosomal abnormalities. The inhibition of PLK1 in mitotic, APC-∆C-expressing cells reduces the kinetochore levels of Aurora B and hampers the recruitment of SAC component suggesting a compromised mitotic checkpoint. Furthermore, Plk1 inhibition (RNAi, pharmacological compounds) promotes the development of adenomatous polyps in two independent Apc Min/+ mouse models. High PLK1 expression increases the survival of colon cancer patients expressing a truncated APC significantly.

Design Optimization for a Truncated Catenary Mooring System for Scale Model Test

Directory of Open Access Journals (Sweden)

Climent Molins

2015-11-01

Full Text Available One of the main aspects when testing floating offshore platforms is the scaled mooring system, particularly with the increased depths where such platforms are intended. The paper proposes the use of truncated mooring systems to emulate the real mooring system by solving an optimization problem. This approach could be an interesting option when the existing testing facilities do not have enough available space. As part of the development of a new spar platform made of concrete for Floating Offshore Wind Turbines (FOWTs, called Windcrete, a station keeping system with catenary shaped lines was selected. The test facility available for the planned experiments had an important width constraint. Then, an algorithm to optimize the design of the scaled truncated mooring system using different weights of lines was developed. The optimization process adjusts the quasi-static behavior of the scaled mooring system as much as possible to the real mooring system within its expected maximum displacement range, where the catenary line provides the restoring forces by its suspended line length.

Left atrial isolation associated with mitral valve operations.

Science.gov (United States)

Graffigna, A; Pagani, F; Minzioni, G; Salerno, J; Viganò, M

1992-12-01

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent mitral valve operations. From May 1989 to September 1991, 62 patients underwent mitral valve operations (group I); 19, mitral valve operations and DeVega tricuspid annuloplasty (group II); 15, mitral and aortic operations (group III); and 4, mitral and aortic operations and DeVega tricuspid annuloplasty (group IV). Left atrial isolation was performed, prolonging the usual left paraseptal atriotomy toward the left fibrous trigone anteriorly and the posteromedial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesions were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 patients (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (group I, 80.7%; group II, 68.5%; group III, 86.7%; group IV, 75%; p = not significant). Three late deaths (3.1%) were registered. Long-term results show persistence of sinus rhythm in 71% of group I, 61.2% of group II, 85.8% of group III, and 100% of group IV. The unique risk factor for late recurrence of atrial fibrillation was found to be preoperative atrial fibrillation longer than 6 months. Due to the satisfactory success rate in recovering sinus rhythm, we suggest performing left atrial isolation in patients with chronic atrial fibrillation undergoing valvular operations.

Hamiltonian truncation approach to quenches in the Ising field theory

Directory of Open Access Journals (Sweden)

T. Rakovszky

2016-10-01

Full Text Available In contrast to lattice systems where powerful numerical techniques such as matrix product state based methods are available to study the non-equilibrium dynamics, the non-equilibrium behaviour of continuum systems is much harder to simulate. We demonstrate here that Hamiltonian truncation methods can be efficiently applied to this problem, by studying the quantum quench dynamics of the 1+1 dimensional Ising field theory using a truncated free fermionic space approach. After benchmarking the method with integrable quenches corresponding to changing the mass in a free Majorana fermion field theory, we study the effect of an integrability breaking perturbation by the longitudinal magnetic field. In both the ferromagnetic and paramagnetic phases of the model we find persistent oscillations with frequencies set by the low-lying particle excitations not only for small, but even for moderate size quenches. In the ferromagnetic phase these particles are the various non-perturbative confined bound states of the domain wall excitations, while in the paramagnetic phase the single magnon excitation governs the dynamics, allowing us to capture the time evolution of the magnetisation using a combination of known results from perturbation theory and form factor based methods. We point out that the dominance of low lying excitations allows for the numerical or experimental determination of the mass spectra through the study of the quench dynamics.

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

Energy Technology Data Exchange (ETDEWEB)

Tang, Yanan; Li, Liang, E-mail: Liang.Li@ualberta.ca

2013-08-20

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. •{sup 12}C{sub 2}-Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released {sup 12}C{sub 2}-dansyl labeled N-terminal amino acid was quantified using {sup 13}C{sub 2}-dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards.

Increased frequency of FBN1 truncating and splicing variants in Marfan syndrome patients with aortic events.

Science.gov (United States)

Baudhuin, Linnea M; Kotzer, Katrina E; Lagerstedt, Susan A

2015-03-01

Marfan syndrome is a systemic disorder that typically involves FBN1 mutations and cardiovascular manifestations. We investigated FBN1 genotype-phenotype correlations with aortic events (aortic dissection and prophylactic aortic surgery) in patients with Marfan syndrome. Genotype and phenotype information from probands (n = 179) with an FBN1 pathogenic or likely pathogenic variant were assessed. A higher frequency of truncating or splicing FBN1 variants was observed in Ghent criteria-positive patients with an aortic event (n = 34) as compared with all other probands (n = 145) without a reported aortic event (79 vs. 39%; P Marfan syndrome patients with FBN1 truncating and splicing variants.Genet Med 17 3, 177-187.

Sleep on the right side-Get cancer on the left?

Science.gov (United States)

Hallberg, Orjan; Johansson, Olle

2010-06-01

Breast cancer frequently occurs in the left breast among both women and men [R. Roychoudhuri, V. Putcha, H. Møller, Cancer and laterality: a study of the five major paired organs (UK), Cancer Causes Control 17 (2006) 655-662; M.T. Goodman, K.H. Tung, L.R. Wilkens, Comparative epidemiology of breast cancer among men and women in the US, 1996 to 2000, Cancer Causes Control 17 (2006) 127-136; C.I. Perkins, J. Hotes, B.A. Kohler, H.L. Howe, Association between breast cancer laterality and tumor location, United States, 1994-1998, Cancer Causes Control 15 (2004) 637-645; H.A. Weiss, S.S. Devesa, L.A. Brinton, Laterality of breast cancer in the United States, Cancer Causes Control 7 (1996) 539-543; A. Ekbom, H.O. Adami, D. Trichopoulos, M. Lambe, C.C. Hsieh, J. Pontén, Epidemiologic correlates of breast cancer laterality (Sweden), Cancer Causes Control 5 (1994) 510-516]. Moreover, recent results showed that the left side of the body is more prone to melanoma than the right side [D.H. Brewster, M.J. Horner, S. Rowan, P. Jelfs, E. de Vries, E. Pukkala, Left-sided excess of invasive cutaneous melanoma in six countries, Eur. J. Cancer 43 (2007) 2634-2637]. Current explanations for left-sided breast cancer include handedness [L. Titus-Ernstoff, P.A. Newcomb, K.M. Egan, et al., Left-handedness in relation to breast cancer risk in postmenopausal women, Epidemiology 11 (2000) 181-184; M.A. Kramer, S. Albrecht, R.A. Miller, Handedness and the laterality of breast cancer in women, Nurs. Res. 34 (1985) 333-337; M.K. Ramadhani, S.G. Elias, P.A. van Noord, D.E. Grobbee, P.H. Peeters, C.S. Uiterwaal, Innate left handedness and risk of breast cancer: case-cohort study, BMJ 331 (2005) 882-883], size difference, nursing preference, and brain structure. However, men are affected even more by left laterality than women, thus many of these explanations are unconvincing. Increasing rates of skin melanoma have been associated with immune-disruptive radiation from FM/TV transmitters [O

Three-dimensional free vibration of functionally graded truncated conical shells subjected to thermal environment

Energy Technology Data Exchange (ETDEWEB)

Malekzadeh, P., E-mail: p_malekz@yahoo.com [Department of Mechanical Engineering, Persian Gulf University, Bushehr 75168 (Iran, Islamic Republic of); Fiouz, A.R.; Sobhrouyan, M. [Department of Civil Engineering, Persian Gulf University, Bushehr 75168 (Iran, Islamic Republic of)

2012-01-15

A three-dimensional (3D) free vibration analysis of the functionally graded (FG) truncated conical shells subjected to thermal environment is presented. The material properties are assumed to be temperature-dependent and graded in the radius direction, which can vary according to a simple power law distribution. The initial thermal stresses are obtained accurately by solving the thermoelastic equilibrium equations and by considering the two-dimensional axisymmetric temperature distribution in the shell. The differential quadrature method (DQM) as an efficient and accurate numerical tool is adopted to solve the thermal and thermo-mechanical governing equations. For this purpose, a mapping technique is employed to transform the cross section of the shell into the computational domain of DQM. The convergence behavior of the method is numerically demonstrated and comparison studies with the available solutions in the literature are performed. The effects of temperature dependence of material properties, geometrical parameters, material graded index, thermal and mechanical boundary conditions on the frequency parameters of the FG truncated conical shells are carried out. - Highlights: Black-Right-Pointing-Pointer 3D free vibration analysis of the functionally graded truncated conical shells is presented. Black-Right-Pointing-Pointer Two-dimensional axisymmetric temperature distribution in the shell is assumed. Black-Right-Pointing-Pointer The material properties are assumed to be temperature-dependent. Black-Right-Pointing-Pointer Initial thermal stresses due to thermal environment are evaluated accurately and included. Black-Right-Pointing-Pointer Representing the effects of different parameters on the non-dimensional frequencies.

Correlations between chaos in a perturbed sine-Gordon equation and a truncated model system

International Nuclear Information System (INIS)

Bishop, A.R.; Flesch, R.; Forests, M.G.; Overman, E.A.

1990-01-01

The purpose of this paper is to present a first step toward providing coordinates and associated dynamics for low-dimensional attractors in nearly integrable partial differential equations (pdes), in particular, where the truncated system reflects salient geometric properties of the pde. This is achieved by correlating: (1) numerical results on the bifurcations to temporal chaos with spatial coherence of the damped, periodically forced sine-Gordon equation with periodic boundary conditions; (2) an interpretation of the spatial and temporal bifurcation structures of this perturbed integrable system with regard to the exact structure of the sine-Gordon phase space; (3) a model dynamical systems problem, which is itself a perturbed integrable Hamiltonian system, derived from the perturbed sine-Gordon equation by a finite mode Fourier truncation in the nonlinear Schroedinger limit; and (4) the bifurcations to chaos in the truncated phase space. In particular, a potential source of chaos in both the pde and the model ordinary differential equation systems is focused on: the existence of homoclinic orbits in the unperturbed integrable phase space and their continuation in the perturbed problem. The evidence presented here supports the thesis that the chaotic attractors of the weakly perturbed periodic sine-Gordon system consists of low-dimensional metastable attacking states together with intermediate states that are O(1) unstable and correspond to homoclinic states in the integrable phase space. It is surmised that the chaotic dynamics on these attractors is due to the perturbation of these homocline integrable configurations

Truncating SLC5A7 mutations underlie a spectrum of dominant hereditary motor neuropathies.

Science.gov (United States)

Salter, Claire G; Beijer, Danique; Hardy, Holly; Barwick, Katy E S; Bower, Matthew; Mademan, Ines; De Jonghe, Peter; Deconinck, Tine; Russell, Mark A; McEntagart, Meriel M; Chioza, Barry A; Blakely, Randy D; Chilton, John K; De Bleecker, Jan; Baets, Jonathan; Baple, Emma L; Walk, David; Crosby, Andrew H

2018-04-01

To identify the genetic cause of disease in 2 previously unreported families with forms of distal hereditary motor neuropathies (dHMNs). The first family comprises individuals affected by dHMN type V, which lacks the cardinal clinical feature of vocal cord paralysis characteristic of dHMN-VII observed in the second family. Next-generation sequencing was performed on the proband of each family. Variants were annotated and filtered, initially focusing on genes associated with neuropathy. Candidate variants were further investigated and confirmed by dideoxy sequence analysis and cosegregation studies. Thorough patient phenotyping was completed, comprising clinical history, examination, and neurologic investigation. dHMNs are a heterogeneous group of peripheral motor neuron disorders characterized by length-dependent neuropathy and progressive distal limb muscle weakness and wasting. We previously reported a dominant-negative frameshift mutation located in the concluding exon of the SLC5A7 gene encoding the choline transporter (CHT), leading to protein truncation, as the likely cause of dominantly-inherited dHMN-VII in an extended UK family. In this study, our genetic studies identified distinct heterozygous frameshift mutations located in the last coding exon of SLC5A7 , predicted to result in the truncation of the CHT C-terminus, as the likely cause of the condition in each family. This study corroborates C-terminal CHT truncation as a cause of autosomal dominant dHMN, confirming upper limb predominating over lower limb involvement, and broadening the clinical spectrum arising from CHT malfunction.

Tailor-made dimensions of diblock copolymer truncated micelles on a solid by UV irradiation.

Science.gov (United States)

Liou, Jiun-You; Sun, Ya-Sen

2015-09-28

We investigated the structural evolution of truncated micelles in ultrathin films of polystyrene-block-poly(2-vinylpyridine), PS-b-P2VP, of monolayer thickness on bare silicon substrates (SiOx/Si) upon UV irradiation in air- (UVIA) and nitrogen-rich (UVIN) environments. The structural evolution of micelles upon UV irradiation was monitored using GISAXS measurements in situ, while the surface morphology was probed using atomic force microscopy ex situ and the chemical composition using X-ray photoelectron spectroscopy (XPS). This work provides clear evidence for the interpretation of the relationship between the structural evolution and photochemical reactions in PS-b-P2VP truncated micelles upon UVIA and UVIN. Under UVIA treatment, photolysis and cross-linking reactions coexisted within the micelles; photolysis occurred mainly at the top of the micelles, whereas cross-linking occurred preferentially at the bottom. The shape and size of UVIA-treated truncated micelles were controlled predominantly by oxidative photolysis reactions, which depended on the concentration gradient of free radicals and oxygen along the micelle height. Because of an interplay between photolysis and photo-crosslinking, the scattering length densities (SLD) of PS and P2VP remained constant. In contrast, UVIN treatments enhanced the contrast in SLD between the PS shell and the P2VP core as cross-linking dominated over photolysis in the presence of nitrogen. The enhancement of the SLD contrast was due to the various degrees of cross-linking under UVIN for the PS and P2VP blocks.

Zero-truncated panel Poisson mixture models: Estimating the impact on tourism benefits in Fukushima Prefecture.

Science.gov (United States)

Narukawa, Masaki; Nohara, Katsuhito

2018-04-01

This study proposes an estimation approach to panel count data, truncated at zero, in order to apply a contingent behavior travel cost method to revealed and stated preference data collected via a web-based survey. We develop zero-truncated panel Poisson mixture models by focusing on respondents who visited a site. In addition, we introduce an inverse Gaussian distribution to unobserved individual heterogeneity as an alternative to a popular gamma distribution, making it possible to capture effectively the long tail typically observed in trip data. We apply the proposed method to estimate the impact on tourism benefits in Fukushima Prefecture as a result of the Fukushima Nuclear Power Plant No. 1 accident. Copyright © 2018 Elsevier Ltd. All rights reserved.

Investigating hospital heterogeneity with a multi-state frailty model: application to nosocomial pneumonia disease in intensive care units

Directory of Open Access Journals (Sweden)

Liquet Benoit

2012-06-01

Full Text Available Abstract Background Multistate models have become increasingly useful to study the evolution of a patient’s state over time in intensive care units ICU (e.g. admission, infections, alive discharge or death in ICU. In addition, in critically-ill patients, data come from different ICUs, and because observations are clustered into groups (or units, the observed outcomes cannot be considered as independent. Thus a flexible multi-state model with random effects is needed to obtain valid outcome estimates. Methods We show how a simple multi-state frailty model can be used to study semi-competing risks while fully taking into account the clustering (in ICU of the data and the longitudinal aspects of the data, including left truncation and right censoring. We suggest the use of independent frailty models or joint frailty models for the analysis of transition intensities. Two distinct models which differ in the definition of time t in the transition functions have been studied: semi-Markov models where the transitions depend on the waiting times and nonhomogenous Markov models where the transitions depend on the time since inclusion in the study. The parameters in the proposed multi-state model may conveniently be computed using a semi-parametric or parametric approach with an existing R package FrailtyPack for frailty models. The likelihood cross-validation criterion is proposed to guide the choice of a better fitting model. Results We illustrate the use of our approach though the analysis of nosocomial infections (ventilator-associated pneumonia infections: VAP in ICU, with “alive discharge” and “death” in ICU as other endpoints. We show that the analysis of dependent survival data using a multi-state model without frailty terms may underestimate the variance of regression coefficients specific to each group, leading to incorrect inferences. Some factors are wrongly significantly associated based on the model without frailty terms. This

Non-perturbative methodologies for low-dimensional strongly-correlated systems: From non-Abelian bosonization to truncated spectrum methods.

Science.gov (United States)

James, Andrew J A; Konik, Robert M; Lecheminant, Philippe; Robinson, Neil J; Tsvelik, Alexei M

2018-02-26

We review two important non-perturbative approaches for extracting the physics of low-dimensional strongly correlated quantum systems. Firstly, we start by providing a comprehensive review of non-Abelian bosonization. This includes an introduction to the basic elements of conformal field theory as applied to systems with a current algebra, and we orient the reader by presenting a number of applications of non-Abelian bosonization to models with large symmetries. We then tie this technique into recent advances in the ability of cold atomic systems to realize complex symmetries. Secondly, we discuss truncated spectrum methods for the numerical study of systems in one and two dimensions. For one-dimensional systems we provide the reader with considerable insight into the methodology by reviewing canonical applications of the technique to the Ising model (and its variants) and the sine-Gordon model. Following this we review recent work on the development of renormalization groups, both numerical and analytical, that alleviate the effects of truncating the spectrum. Using these technologies, we consider a number of applications to one-dimensional systems: properties of carbon nanotubes, quenches in the Lieb-Liniger model, 1  +  1D quantum chromodynamics, as well as Landau-Ginzburg theories. In the final part we move our attention to consider truncated spectrum methods applied to two-dimensional systems. This involves combining truncated spectrum methods with matrix product state algorithms. We describe applications of this method to two-dimensional systems of free fermions and the quantum Ising model, including their non-equilibrium dynamics.

Non-perturbative methodologies for low-dimensional strongly-correlated systems: From non-Abelian bosonization to truncated spectrum methods

Science.gov (United States)

James, Andrew J. A.; Konik, Robert M.; Lecheminant, Philippe; Robinson, Neil J.; Tsvelik, Alexei M.

2018-04-01

We review two important non-perturbative approaches for extracting the physics of low-dimensional strongly correlated quantum systems. Firstly, we start by providing a comprehensive review of non-Abelian bosonization. This includes an introduction to the basic elements of conformal field theory as applied to systems with a current algebra, and we orient the reader by presenting a number of applications of non-Abelian bosonization to models with large symmetries. We then tie this technique into recent advances in the ability of cold atomic systems to realize complex symmetries. Secondly, we discuss truncated spectrum methods for the numerical study of systems in one and two dimensions. For one-dimensional systems we provide the reader with considerable insight into the methodology by reviewing canonical applications of the technique to the Ising model (and its variants) and the sine-Gordon model. Following this we review recent work on the development of renormalization groups, both numerical and analytical, that alleviate the effects of truncating the spectrum. Using these technologies, we consider a number of applications to one-dimensional systems: properties of carbon nanotubes, quenches in the Lieb–Liniger model, 1  +  1D quantum chromodynamics, as well as Landau–Ginzburg theories. In the final part we move our attention to consider truncated spectrum methods applied to two-dimensional systems. This involves combining truncated spectrum methods with matrix product state algorithms. We describe applications of this method to two-dimensional systems of free fermions and the quantum Ising model, including their non-equilibrium dynamics.

Characterization of mTOR-Responsive Truncated mRNAs in Cell Proliferation

Science.gov (United States)

2017-07-01

These findings identify a previously uncharacterized role for mTOR in modulating 3’- UTR length of mRNAs by alternative polyadenylation ( APA ). Another...outcome of APA in the mTOR-activated transcriptome is an early termination of mRNA transcription to produce truncated mRNAs with polyadenylation in...for exhaustive analysis of Alternative cleavage and polyadenylation ( APA ) events (Figure 1). In IntMAP, first the position of multiple

Increased left ventricular mass in normotensive type 1 diabetic patients with diabetic nephropathy

DEFF Research Database (Denmark)

Sato, A; Tarnow, L; Parving, H H

1998-01-01

in normotensive type 1 diabetic patients with and without nephropathy. RESEARCH DESIGN AND METHODS: M-mode and Doppler echocardiography was performed in 17 type 1 diabetic patients with nephropathy (albuminuria [median (range)], 345 (135-2,846) mg/24 h) and compared with 34 normotensive, normoalbuminuric (10 [3......-30] mg/24 h) type 1 diabetic patients matched for arterial blood pressure (mean +/- SD) ([134/77] +/- [13/7] vs. [129/78] +/- [12/7] mmHg), age (40 +/- 11 vs. 42 +/- 10 years), duration of diabetes (28 +/- 7 vs. 28 +/- 6 years), and BMI (24.2 +/- 4.2 vs. 24.6 +/- 2.4 kg/m2). RESULTS: Left ventricular......OBJECTIVE: Diabetic nephropathy increases the risk of premature cardiovascular disease and sudden death, particularly in type 1 diabetic patients. One possible mechanism for this risk may be left ventricular hypertrophy. In our study, we aimed to evaluate left ventricular structure and function...

Truncated conformal space approach to scaling Lee-Yang model

International Nuclear Information System (INIS)

Yurov, V.P.; Zamolodchikov, Al.B.

1989-01-01

A numerical approach to 2D relativstic field theories is suggested. Considering a field theory model as an ultraviolet conformal field theory perturbed by suitable relevant scalar operator one studies it in finite volume (on a circle). The perturbed Hamiltonian acts in the conformal field theory space of states and its matrix elements can be extracted from the conformal field theory. Truncation of the space at reasonable level results in a finite dimensional problem for numerical analyses. The nonunitary field theory with the ultraviolet region controlled by the minimal conformal theory μ(2/5) is studied in detail. 9 refs.; 17 figs

Phospholipid lateral diffusion in phosphatidylcholine-sphingomyelin-cholesterol monolayers; Effects of oxidatively truncated phosphatidylcholines

Czech Academy of Sciences Publication Activity Database

Parkkila, P.; Štefl, Martin; Olžyńska, Agnieszka; Hof, Martin; Kinnunen, P. K. J.

2015-01-01

Roč. 1848, č. 1 (2015), s. 167-173 ISSN 0005-2736 R&D Projects: GA ČR GBP208/12/G016 Institutional support: RVO:61388955 Keywords : Oxidatively truncated phosphatidylcholines * Lateral diffusion * Fluorescence correlation spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.687, year: 2015

Heterogeneous autoregressive model with structural break using nearest neighbor truncation volatility estimators for DAX.

Science.gov (United States)

Chin, Wen Cheong; Lee, Min Cherng; Yap, Grace Lee Ching

2016-01-01

High frequency financial data modelling has become one of the important research areas in the field of financial econometrics. However, the possible structural break in volatile financial time series often trigger inconsistency issue in volatility estimation. In this study, we propose a structural break heavy-tailed heterogeneous autoregressive (HAR) volatility econometric model with the enhancement of jump-robust estimators. The breakpoints in the volatility are captured by dummy variables after the detection by Bai-Perron sequential multi breakpoints procedure. In order to further deal with possible abrupt jump in the volatility, the jump-robust volatility estimators are composed by using the nearest neighbor truncation approach, namely the minimum and median realized volatility. Under the structural break improvements in both the models and volatility estimators, the empirical findings show that the modified HAR model provides the best performing in-sample and out-of-sample forecast evaluations as compared with the standard HAR models. Accurate volatility forecasts have direct influential to the application of risk management and investment portfolio analysis.

Expression of a truncated receptor protein tyrosine phosphatase kappa in the brain of an adult transgenic mouse

DEFF Research Database (Denmark)

Shen, P; Canoll, P D; Sap, J

1999-01-01

that goal, we have used this mouse model to map the distribution of the truncated RPTP-kappa/beta-geo fusion protein in the adult mouse brain using beta-galactosidase as a marker enzyme. Visualization of the beta-galactosidase activity revealed a non-random pattern of expression, and identified cells......-6596]. Nevertheless, since the transgene's expression is driven by the endogenous RPTP-kappa promoter, distribution of the truncated RPTP-kappa/beta-geo fusion protein should reflect the regional and cellular expression of wild-type RPTP-kappa, and thus may identify sites where RPTP-kappa is important. Towards...

The left ventricle in aortic stenosis--imaging assessment and clinical implications.

Science.gov (United States)

Călin, Andreea; Roşca, Monica; Beladan, Carmen Cristiana; Enache, Roxana; Mateescu, Anca Doina; Ginghină, Carmen; Popescu, Bogdan Alexandru

2015-04-29

Aortic stenosis has an increasing prevalence in the context of aging population. In these patients non-invasive imaging allows not only the grading of valve stenosis severity, but also the assessment of left ventricular function. These two goals play a key role in clinical decision-making. Although left ventricular ejection fraction is currently the only left ventricular function parameter that guides intervention, current imaging techniques are able to detect early changes in LV structure and function even in asymptomatic patients with significant aortic stenosis and preserved ejection fraction. Moreover, new imaging parameters emerged as predictors of disease progression in patients with aortic stenosis. Although proper standardization and confirmatory data from large prospective studies are needed, these novel parameters have the potential of becoming useful tools in guiding intervention in asymptomatic patients with aortic stenosis and stratify risk in symptomatic patients undergoing aortic valve replacement.This review focuses on the mechanisms of transition from compensatory left ventricular hypertrophy to left ventricular dysfunction and heart failure in aortic stenosis and the role of non-invasive imaging assessment of the left ventricular geometry and function in these patients.

A comparative analysis of suicide attempts in left-behind children and non-left-behind children in rural China.

Science.gov (United States)

Chang, Hongjuan; Yan, Qiuge; Tang, Lina; Huang, Juan; Ma, Yuqiao; Ye, Xiaozhou; Yu, Yizhen

2017-01-01

To estimate the prevalence of suicide attempts and explore the shared and unique factors influencing suicide risk in left-behind children (LBC) and non-left-behind children (NLBC) in rural China, this study collected data using a multi-stage cluster random sampling method from 13,952 children including 6,034 LBC and 7,918 NLBC. Sociodemographic characteristics, suicide attempts, neglect and physical abuse, negative life events, and loneliness were measured by self-reported questionnaires. Data were analyzed using logistic regression models. Gender and mother's education level were unique influential factors for NLBC while family structure type was a unique influential factor for LBC. The study provides two novel findings regarding NLBC specifically: 1. Children with optimal family socioeconomic status are more likely to report suicide attempts (odds ratio OR = 1)than are those in the general children population, OR 0.52 (95% CI: 0.39-0.70), and 2. Children with higher mother's education level are subject to higher suicide rates in high school, OR 1.67 (95% CI: 1.13-2.46), and post-secondary education, OR 2.14 (95% CI: 1.37-3.37). The unique characteristics of LBC and NLBC in China suggest that investigating risk factors and determining the factors that might be targeted in intervention programs are urgently needed currently.

Permanent right-to-left shunt is the key factor in managing patent foramen ovale.

Science.gov (United States)

Rigatelli, Gianluca; Dell'Avvocata, Fabio; Cardaioli, Paolo; Giordan, Massimo; Braggion, Gabriele; Aggio, Silvio; Chinaglia, Mauro; Mandapaka, Sangeeta; Kuruvilla, John; Chen, Jack P; Nanjundappa, Aravinda

2011-11-15

We sought to prospectively evaluate risk of stroke and impact of transcatheter patent foramen ovale (PFO) closure in patients with permanent right-to left shunt compared with those with Valsalva maneuver-induced right-to-left shunt. Pathophysiology and properly management of PFO still remain far from being fully clarified: in particular, the contribution of permanent right-to-left shunt remains unknown. Between March 2006 and October 2010, we enrolled 180 (mean age 44 ± 10.9 years, 98 women) of 320 consecutive patients referred to our center for transcatheter PFO closure, who had spontaneous permanent right-to-left shunt on transcranial Doppler and transthoracic/transesophageal echocardiography. All patients fulfilled the standard current indications for transcatheter closure and underwent preoperative transesophageal echocardiography and brain magnetic resonance imaging, with subsequent intracardiac echocardiographic-guided transcatheter PFO closure. We compared the clinical echocardiographic characteristics of these patients (Permanent Group) with the rest of 140 patients with right-to-left shunt only during Valsalva maneuver (Valsalva Group). Compared with the Valsalva Group patients, patients of the Permanent Group had increased frequency of multiple ischemic brain lesions on magnetic resonance imaging, previous recurrent stroke, previous peripheral arteries embolism, migraine with aura, and-more frequently-atrial septal aneurysm and prominent Eustachian valve. The presence of permanent shunt confers the highest risk of recurrent stroke (odds ratio: 5.9, 95% confidence interval: 2.0 to 12, p < 0.001). No differences were recorded between the 2 groups with regard to recurrence of ischemic events after the closure procedure. Despite its small-sample nature, our study suggests that patients with permanent right-to-left shunt have potentially a higher risk of paradoxical embolism compared with those without. Copyright © 2011 American College of Cardiology

Entanglement entropy from the truncated conformal space

Directory of Open Access Journals (Sweden)

T. Palmai

2016-08-01

Full Text Available A new numerical approach to entanglement entropies of the Rényi type is proposed for one-dimensional quantum field theories. The method extends the truncated conformal spectrum approach and we will demonstrate that it is especially suited to study the crossover from massless to massive behavior when the subsystem size is comparable to the correlation length. We apply it to different deformations of massless free fermions, corresponding to the scaling limit of the Ising model in transverse and longitudinal fields. For massive free fermions the exactly known crossover function is reproduced already in very small system sizes. The new method treats ground states and excited states on the same footing, and the applicability for excited states is illustrated by reproducing Rényi entropies of low-lying states in the transverse field Ising model.

Quasi-SU(3) truncation scheme for even-even sd-shell nuclei

International Nuclear Information System (INIS)

Vargas, C.E.; Hirsch, J.G.; Draayer, J.P.

2001-01-01

The quasi-SU(3) symmetry was uncovered in full pf and sdg shell-model calculations for both even-even and odd-even nuclei. It manifests itself through a dominance of single-particle and quadrupole-quadrupole terms in a Hamiltonian used to describe well-deformed nuclei. A practical consequence of the quasi-SU(3) symmetry is an efficient basis truncation scheme. In [C.E. Vargas et al., Phys. Rev. C 58 (1998) 1488] it is shown that when this type of Hamiltonian is diagonalized in an SU(3) basis, only a few irreducible representations (irreps) of SU(3) are needed to describe the yrast band, the leading S=0 irrep augmented with the leading S=1 irreps in the proton and neutron subspaces. In the present article the quasi-SU(3) truncation scheme is used, in conjunction with a 'realistic but schematic' Hamiltonian that includes the most important multipole terms, to describe the energy spectra and B(E2) transition strengths of 20,22 Ne, 24 Mg and 28 Si. The effect of the size of the Hilbert space on both sets of observables is discussed, as well as the structure of the yrast band and the importance of the various terms in the Hamiltonian. The limitations of the model are explicitly discussed

Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

DEFF Research Database (Denmark)

Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P

2013-01-01

Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation...... [high left ventricular end-diastolic volume (EDV) index and concentricity (LVM/EDV)] in hypertensive patients....

Impact of fasting glucose on electrocardiographic left ventricular hypertrophy in an elderly general population

DEFF Research Database (Denmark)

Diederichsen, Søren Z; Pareek, Manan; Nielsen, Mette L

2015-01-01

OBJECTIVE: To evaluate relationships between fasting plasma glucose (FPG), other cardiovascular risk markers and left ventricular hypertrophy (LVH) as detected by electrocardiography. METHODS: Subjects were selected randomly from groups defined by FPG. Traditional risk markers were assessed. LVH...

Laparoscopic colostomy for acute left colon obstruction caused by diverticular disease in high risk patient: A case report.

Science.gov (United States)

Palladino, Elisa; Cappiello, Antonio; Guarino, Vincenzo; Perrotta, Nicola; Loffredo, Domenico

2015-01-01

The colostomy is often necessary in complicated divertcular disease. The laparoscopic colostomy is not widely used for the treatment of complicated diverticular disease. Its use in patients with high operative risk is still on debate. The aim of this case report was to present the benefits of laparoscopic colostomy in patients with high peri-and postoperative risk factors. We present a case of 76-year-old female admitted to emergency unit for left colonic obstruction. The patient had a past history of liver cirrhosis HCV-related with a severe malnutrition, hypertrophic cardiomyopathy, diverticular disease, hiatal ernia, previous appendectomy. Patient was classified according to their preoperative risk ASA 3 (classification of the American society of Anestesia-ASA score). Contrast-enhanced abdominal CT revealed a marked thickening in the sigmoid colon and a marked circumferential stenosis in the sigmoid colon in absence of neoplasm, and/or abscess. The laparoscopic procedure is proposed as first intention. The operation time was 50min, and the hospital stay was 4 days. Post operative complications grade I according to the Clavien Dindo Classification. Laparoscopic colostomy is safe and feasible procedure in experienced hands. It is associated with low morbidity and short stay in hospital and should be considered a good alternative to a laparotomy. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

On the propagation of truncated localized waves in dispersive silica

KAUST Repository

Salem, Mohamed

2010-01-01

Propagation characteristics of truncated Localized Waves propagating in dispersive silica and free space are numerically analyzed. It is shown that those characteristics are affected by the changes in the relation between the transverse spatial spectral components and the wave vector. Numerical experiments demonstrate that as the non-linearity of this relation gets stronger, the pulses propagating in silica become more immune to decay and distortion whereas the pulses propagating in free-space suffer from early decay and distortion. © 2010 Optical Society of America.

Selective apoptosis induction in MCF-7 cell line by truncated minimal functional region of Apoptin

International Nuclear Information System (INIS)

Shen Ni, Lim; Allaudin, Zeenathul Nazariah bt; Mohd Lila, Mohd Azmi b; Othman, Abas Mazni b; Othman, Fauziah bt

2013-01-01

Chicken Anemia Virus (CAV) VP3 protein (also known as Apoptin), a basic and proline-rich protein has a unique capability in inducing apoptosis in cancer cells but not in normal cells. Five truncated Apoptin proteins were analyzed to determine their selective ability to migrate into the nucleus of human breast adenocarcinoma MCF-7 cells for inducing apoptosis. For identification of the minimal selective domain for apoptosis, the wild-type Apoptin gene had been reconstructed by PCR to generate segmental deletions at the N’ terminal and linked with nuclear localization sites (NLS1 and NLS2). All the constructs were fused with maltose-binding protein gene and individually expressed by in vitro Rapid Translation System. Standardized dose of proteins were delivered into human breast adenocarcinoma MCF-7 cells and control human liver Chang cells by cytoplasmic microinjection, and subsequently observed for selective apoptosis effect. Three of the truncated Apoptin proteins with N-terminal deletions spanning amino acid 32–83 retained the cancer selective nature of wild-type Apoptin. The proteins were successfully translocated to the nucleus of MCF-7 cells initiating apoptosis, whereas non-toxic cytoplasmic retention was observed in normal Chang cells. Whilst these truncated proteins retained the tumour-specific death effector ability, the specificity for MCF-7 cells was lost in two other truncated proteins that harbor deletions at amino acid 1–31. The detection of apoptosing normal Chang cells and MCF-7 cells upon cytoplasmic microinjection of these proteins implicated a loss in Apoptin’s signature targeting activity. Therefore, the critical stretch spanning amino acid 1–31 at the upstream of a known hydrophobic leucine-rich stretch (LRS) was strongly suggested as one of the prerequisite region in Apoptin for cancer targeting. Identification of this selective domain provides a platform for developing small targets to facilitating carrier-mediated-transport across

Surgical myocardial revascularization in patients with reduced systolic left ventricular function.

Science.gov (United States)

Bruno, Piergiorgio; Iafrancesco, Mauro; Massetti, Massimo

2018-04-20

Surgical myocardial revascularization in patients with reduced left ventricular function has been a matter of debate for decades. Recently published 10-years extension follow-up of the STICH trial have conclusively demonstrated benefit of surgical myocardial revascularization in patients with significant coronary artery disease and low left ventricular ejection fraction. However, selection of patients for surgery remains challenging as well as decision to perform percutaneous rather than surgical revascularization in this class of patients. New evidence helped to clarify the role of preoperative patients' characteristics as risk factors for surgery and to identify those patients who may benefit the most from surgery. Focus of this review is to review epidemiology, aetiology and pathophysiology of coronary artery disease in patients with reduced left ventricular function, role of viability and results of observational and investigational studies on revascularization in patients with reduced left ventricular function with a particular emphasis on relative indication of coronary artery bypass grafting and percutaneous coronary intervention and the surgical implications of development of ischemic mitral regurgitation or ischemic left ventricular aneurysm.

Kidney Disease Measures and Left Ventricular Structure and Function: The Atherosclerosis Risk in Communities Study.

Science.gov (United States)

Matsushita, Kunihiro; Kwak, Lucia; Sang, Yingying; Ballew, Shoshana H; Skali, Hicham; Shah, Amil M; Coresh, Josef; Solomon, Scott

2017-09-22

Heart failure is one of the most important complications of chronic kidney disease (CKD). However, few studies comprehensively investigated left ventricular (LV) structure and function in relation to 2 key CKD measures, estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR). Among 4175 ARIC (Atherosclerosis Risk in Communities) participants (aged 66-90 years during 2011-2013), we quantified the association of eGFR and ACR with echocardiogram parameters of LV mass, size, systolic function, and diastolic function. Adjusting for demographic variables, both CKD measures were significantly associated with most echocardiogram parameters. Additionally accounting for other potential confounders, we observed significantly higher LV mass index according to reduced eGFR (82.3 [95% confidence interval (CI), 77.6-87.0] g/m 2 for eGFR function, significant differences were observed for some parameters, particularly at eGFR function were robustly associated with albuminuria. These results have implications for pathophysiological processes behind cardiorenal syndrome and targeted cardiac assessment in patients with CKD. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Ab Initio Study of 40Ca with an Importance Truncated No-Core Shell Model

Energy Technology Data Exchange (ETDEWEB)

Roth, R; Navratil, P

2007-05-22

We propose an importance truncation scheme for the no-core shell model, which enables converged calculations for nuclei well beyond the p-shell. It is based on an a priori measure for the importance of individual basis states constructed by means of many-body perturbation theory. Only the physically relevant states of the no-core model space are considered, which leads to a dramatic reduction of the basis dimension. We analyze the validity and efficiency of this truncation scheme using different realistic nucleon-nucleon interactions and compare to conventional no-core shell model calculations for {sup 4}He and {sup 16}O. Then, we present the first converged calculations for the ground state of {sup 40}Ca within no-core model spaces including up to 16{h_bar}{Omega}-excitations using realistic low-momentum interactions. The scheme is universal and can be easily applied to other quantum many-body problems.

Left-sided breast cancer and risks of secondary lung cancer and ischemic heart disease. Effects of modern radiotherapy techniques

Energy Technology Data Exchange (ETDEWEB)

Corradini, Stefanie; Ballhausen, Hendrik; Weingandt, Helmut; Freislederer, Philipp; Schoenecker, Stephan; Niyazi, Maximilian; Belka, Claus [University Hospital, LMU Munich, Department of Radiation Oncology, Munich (Germany); Simonetto, Cristoforo; Eidemueller, Markus [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, Neuherberg (Germany); Ganswindt, Ute [University Hospital, LMU Munich, Department of Radiation Oncology, Munich (Germany); Medical University, Department of Radiation Oncology, Innsbruck (Austria)

2018-03-15

Modern breast cancer radiotherapy techniques, such as respiratory-gated radiotherapy in deep-inspiration breath-hold (DIBH) or volumetric-modulated arc radiotherapy (VMAT) have been shown to reduce the high dose exposure of the heart in left-sided breast cancer. The aim of the present study was to comparatively estimate the excess relative and absolute risks of radiation-induced secondary lung cancer and ischemic heart disease for different modern radiotherapy techniques. Four different treatment plans were generated for ten computed tomography data sets of patients with left-sided breast cancer, using either three-dimensional conformal radiotherapy (3D-CRT) or VMAT, in free-breathing (FB) or DIBH. Dose-volume histograms were used for organ equivalent dose (OED) calculations using linear, linear-exponential, and plateau models for the lung. A linear model was applied to estimate the long-term risk of ischemic heart disease as motivated by epidemiologic data. Excess relative risk (ERR) and 10-year excess absolute risk (EAR) for radiation-induced secondary lung cancer and ischemic heart disease were estimated for different representative baseline risks. The DIBH maneuver resulted in a significant reduction of the ERR and estimated 10-year excess absolute risk for major coronary events compared to FB in 3D-CRT plans (p = 0.04). In VMAT plans, the mean predicted risk reduction through DIBH was less pronounced and not statistically significant (p = 0.44). The risk of radiation-induced secondary lung cancer was mainly influenced by the radiotherapy technique, with no beneficial effect through DIBH. VMAT plans correlated with an increase in 10-year EAR for radiation-induced lung cancer as compared to 3D-CRT plans (DIBH p = 0.007; FB p = 0.005, respectively). However, the EARs were affected more strongly by nonradiation-associated risk factors, such as smoking, as compared to the choice of treatment technique. The results indicate that 3D-CRT plans in DIBH pose the lowest

LONG-TERM EFFECTS OF CHLORTHALIDONE VS HYDROCHLOROTHIAZIDE ON ELECTROCARDIOGRAPHIC LEFT VENTRICULAR HYPERTROPHY IN THE MULTIPLE RISK FACTOR INTERVENTION TRIAL

Science.gov (United States)

Ernst, Michael E.; Neaton, James D.; Grimm, Richard H.; Collins, Gary; Thomas, William; Soliman, Elsayed Z.; Prineas, Ronald J.

2011-01-01

Chlorthalidone (CTD) reduces 24-hour blood pressure more effectively than hydrochlorothiazide (HCTZ), but whether this influences electrocardiographic left ventricular hypertrophy (LVH) is uncertain. One source of comparative data is the Multiple Risk Factor Intervention Trial (MRFIT), which randomly assigned 8,012 hypertensive men to special intervention (SI) or usual care (UC). SI participants could use CTD or HCTZ initially; previous analyses have grouped clinics by their main diuretic used (C-clinics: CTD; H-clinics: HCTZ). After 48 months, SI participants receiving HCTZ were recommended to switch to CTD, in part, because higher mortality was observed for SI compared to UC participants in H-clinics, while the opposite was found in C-clinics. In this analysis, we examined change in continuous measures of electrocardiographic LVH using both an ecologic analysis by previously-reported C- or H-clinic groupings, and an individual participant analysis where use of CTD or HCTZ by SI participants was considered and updated annually. Through 48 months, differences between SI and UC in LVH were larger for C-clinics compared to H-clinics (Sokolow-Lyon: −93.9 vs −54.9 μV, P=0.049; Cornell voltage: −68.1 vs −35.9 μV, P=0.019; Cornell voltage product: −4.6 vs −2.2 μV/ms, P=0.071; left ventricular mass: −4.4 vs −2.8 gm, P=0.002). At the individual participant level, Sokolow-Lyon and left ventricular mass were significantly lower for SI men receiving CTD compared to HCTZ through 48 months and 84 months of follow-up. Our findings on LVH support the idea that greater blood pressure reduction with CTD than HCTZ may have led to differences in mortality observed in MRFIT. PMID:22025372

Solution of the Stieltjes truncated matrix moment problem

Directory of Open Access Journals (Sweden)

Vadim M. Adamyan

2005-01-01

Full Text Available The truncated Stieltjes matrix moment problem consisting in the description of all matrix distributions \\(\\boldsymbol{\\sigma}(t\\ on \\([0,\\infty\\ with given first \\(2n+1\\ power moments \\((\\mathbf{C}_j_{n=0}^j\\ is solved using known results on the corresponding Hamburger problem for which \\(\\boldsymbol{\\sigma}(t\\ are defined on \\((-\\infty,\\infty\\. The criterion of solvability of the Stieltjes problem is given and all its solutions in the non-degenerate case are described by selection of the appropriate solutions among those of the Hamburger problem for the same set of moments. The results on extensions of non-negative operators are used and a purely algebraic algorithm for the solution of both Hamburger and Stieltjes problems is proposed.

Developmental regulation of human truncated nerve growth factor receptor

Energy Technology Data Exchange (ETDEWEB)

DiStefano, P.S.; Clagett-Dame, M.; Chelsea, D.M.; Loy, R. (Abbott Laboratories, Abbott Park, IL (USA))

1991-01-01

Monoclonal antibodies (designated XIF1 and IIIG5) recognizing distinct epitopes of the human truncated nerve growth factor receptor (NGF-Rt) were used in a two-site radiometric immunosorbent assay to monitor levels of NGF-Rt in human urine as a function of age. Urine samples were collected from 70 neurologically normal subjects ranging in age from 1 month to 68 years. By using this sensitive two-site radiometric immunosorbent assay, NGF-Rt levels were found to be highest in urine from 1-month old subjects. By 2.5 months, NGF-Rt values were half of those seen at 1 month and decreased more gradually between 0.5 and 15 years. Between 15 and 68 years, urine NGF-Rt levels were relatively constant at 5% of 1-month values. No evidence for diurnal variation of adult NGF-Rt was apparent. Pregnant women in their third trimester showed significantly elevated urine NGF-Rt values compared with age-matched normals. Affinity labeling of NGF-Rt with 125I-NGF followed by immunoprecipitation with ME20.4-IgG and gel autoradiography indicated that neonatal urine contained high amounts of truncated receptor (Mr = 50 kd); decreasingly lower amounts of NGF-Rt were observed on gel autoradiograms with development, indicating that the two-site radiometric immunosorbent assay correlated well with the affinity labeling technique for measuring NGF-Rt. NGF-Rt in urines from 1-month-old and 36-year-old subjects showed no differences in affinities for NGF or for the monoclonal antibody IIIG5. These data show that NGF-Rt is developmentally regulated in human urine, and are discussed in relation to the development and maturation of the peripheral nervous system.

Developmental regulation of human truncated nerve growth factor receptor

International Nuclear Information System (INIS)

DiStefano, P.S.; Clagett-Dame, M.; Chelsea, D.M.; Loy, R.

1991-01-01

Monoclonal antibodies (designated XIF1 and IIIG5) recognizing distinct epitopes of the human truncated nerve growth factor receptor (NGF-Rt) were used in a two-site radiometric immunosorbent assay to monitor levels of NGF-Rt in human urine as a function of age. Urine samples were collected from 70 neurologically normal subjects ranging in age from 1 month to 68 years. By using this sensitive two-site radiometric immunosorbent assay, NGF-Rt levels were found to be highest in urine from 1-month old subjects. By 2.5 months, NGF-Rt values were half of those seen at 1 month and decreased more gradually between 0.5 and 15 years. Between 15 and 68 years, urine NGF-Rt levels were relatively constant at 5% of 1-month values. No evidence for diurnal variation of adult NGF-Rt was apparent. Pregnant women in their third trimester showed significantly elevated urine NGF-Rt values compared with age-matched normals. Affinity labeling of NGF-Rt with 125I-NGF followed by immunoprecipitation with ME20.4-IgG and gel autoradiography indicated that neonatal urine contained high amounts of truncated receptor (Mr = 50 kd); decreasingly lower amounts of NGF-Rt were observed on gel autoradiograms with development, indicating that the two-site radiometric immunosorbent assay correlated well with the affinity labeling technique for measuring NGF-Rt. NGF-Rt in urines from 1-month-old and 36-year-old subjects showed no differences in affinities for NGF or for the monoclonal antibody IIIG5. These data show that NGF-Rt is developmentally regulated in human urine, and are discussed in relation to the development and maturation of the peripheral nervous system

Effect of Truncating AUC at 12, 24 and 48 hr When Evaluating the Bioequivalence of Drugs with a Long Half-Life.

Science.gov (United States)

Moreno, Isabel; Ochoa, Dolores; Román, Manuel; Cabaleiro, Teresa; Abad-Santos, Francisco

2016-01-01

Bioequivalence studies of drugs with a long half-life require long periods of time for pharmacokinetic sampling. The latest update of the European guideline allows the area under the curve (AUC) truncated at 72 hr to be used as an alternative to AUC0-t as the primary parameter. The objective of this study was to evaluate the effect of truncating the AUC at 48, 24 and 12 hr on the acceptance of the bioequivalence criterion as compared with truncation at 72 hr in bioequivalence trials. The effect of truncated AUC on the within-individual coefficient of variation (CVw) and on the ratio of the formulations was also analysed. Twenty-eight drugs were selected from bioequivalence trials. Pharmacokinetic data were analysed using WinNonLin 2.0 based on the trapezoidal method. Analysis of variance (ANOVA) was performed to obtain the ratios and 90% confidence intervals for AUC at different time-points. The degree of agreement of AUC0-72 in relation to AUC0-48 and AUC0-24, according to the Landis and Koch classification, was 'almost perfect'. Statistically significant differences were observed when the CVw of AUC truncated at 72, 48 and 24 hr was compared with the CVw of AUC0-12. There were no statistically significant differences in the AUC ratio at any time-point. Compared to AUC0-72, Pearson's correlation coefficient for mean AUC, AUC ratio and AUC CVw was worse for AUC0-12 than AUC0-24 or AUC0-48. These preliminary results could suggest that AUC truncation at 24 or 48 hr is adequate to determine whether two formulations are bioequivalent. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Truncation effects in connected arrays: Analytical models to describe the edge-induced wave phenomena

NARCIS (Netherlands)

Neto, A.; Cavallo, D.; Gerini, G.

2011-01-01

This paper presents a Green's function based procedure to assess edge effects in finite wideband connected arrays. Truncation effects are more severe in broadband arrays, since the inter-element mutual coupling facilitates the propagation of edge-born waves that can become dominant over large

Electron transfer reactions, cyanide and O2 binding of truncated hemoglobin from Bacillus subtilis

DEFF Research Database (Denmark)

Fernandez, Esther; Larsson, Jonas T.; McLean, Kirsty J.

2013-01-01

The truncated hemoglobin from Bacillus subtilis (trHb-Bs) possesses a surprisingly high affinity for oxygen and resistance to (auto)oxidation; its physiological role in the bacterium is not understood and may be connected with its very special redox and ligand binding reactions. Electron transfer...

One-step green synthesis of cuprous oxide crystals with truncated octahedra shapes via a high pressure flux approach

International Nuclear Information System (INIS)

Li Benxian; Wang Xiaofeng; Xia Dandan; Chu Qingxin; Liu Xiaoyang; Lu Fengguo; Zhao Xudong

2011-01-01

Cuprous oxide (Cu 2 O) was synthesized via reactions between cupric oxide (CuO) and copper metal (Cu) at a low temperature of 300 deg. C. This progress is green, environmentally friendly and energy efficient. Cu 2 O crystals with truncated octahedra morphology were grown under high pressure using sodium hydroxide (NaOH) and potassium hydroxide (KOH) with a molar ratio of 1:1 as a flux. The growth mechanism of Cu 2 O polyhedral microcrystals are proposed and discussed. - Graphical Abstract: The Cu 2 O crystals with truncated octahedral shape were one-step synthesized in high yield via high pressure flux method for the first time, which is green and environmentally friendly. The mechanisms of synthesis and crystal growth were discussed in this paper. Highlights: → Cuprous oxide was one-step green synthesized by high pressure flux method. → The approach was based on the reverse dismutation reactions between cupric oxide and copper metal. → This progress is green, environmentally friendly and energy efficient. → The synthesized Cu2O crystals were of truncated octahedra morphology.

Enhanced cell surface expression, immunogenicity and genetic stability resulting from a spontaneous truncation of HIV Env expressed by a recombinant MVA

International Nuclear Information System (INIS)

Wyatt, Linda S.; Belyakov, Igor M.; Earl, Patricia L.; Berzofsky, Jay A.; Moss, Bernard

2008-01-01

During propagation of modified vaccinia virus Ankara (MVA) encoding HIV 89.6 Env, a few viral foci stained very prominently. Virus cloned from such foci replicated to higher titers than the parent and displayed enhanced genetic stability on passage. Sequence analysis showed a single nucleotide deletion in the 89.6 env gene of the mutant that caused a frame shift and truncation of 115 amino acids from the cytoplasmic domain. The truncated Env was more highly expressed on the cell surface, induced higher antibody responses than the full-length Env, reacted with HIV neutralizing monoclonal antibodies and mediated CD4/co-receptor-dependent fusion. Intramuscular (IM), intradermal (ID) needleless, and intrarectal (IR) catheter inoculations gave comparable serum IgG responses. However, intraoral (IO) needleless injector route gave the highest IgA in lung washings and IR gave the highest IgA and IgG responses in fecal extracts. Induction of CTL responses in the spleens of individual mice as assayed by intracellular cytokine staining was similar with both the full-length and truncated Env constructs. Induction of acute and memory CTL in the spleens of mice immunized with the truncated Env construct by ID, IO, and IR routes was comparable and higher than by the IM route, but only the IR route induced CTL in the gut-associated lymphoid tissue. Thus, truncation of Env enhanced genetic stability as well as serum and mucosal antibody responses, suggesting the desirability of a similar modification in MVA-based candidate HIV vaccines

Shell model truncation schemes for rotational nuclei

International Nuclear Information System (INIS)

Halse, P.; Jaqua, L.; Barrett, B.R.

1990-01-01

The suitability of the pair condensate approach for rotational states is studied in a single j = 17/2 shell of identical nucleons interacting through a quadrupole-quadrupole hamiltonian. The ground band and a K = 2 excited band are both studied in detail. A direct comparison of the exact states with those constituting the SD and SDG subspaces is used to identify the important degrees of freedom for these levels. The range of pairs necessary for a good description is found to be highly state dependent; S and D pairs are the major constituents of the low-spin ground band levels, while G pairs are needed for those in the γ-band. Energy spectra are obtained for each truncated subspace. SDG pairs allow accurate reproduction of the binding energy and K = 2 excitation energy, but still give a moment of inertia which is about 30% too small even for the lowest levels

N-terminally truncated forms of human cathepsin F accumulate in aggresome-like inclusions.

Science.gov (United States)

Jerič, Barbara; Dolenc, Iztok; Mihelič, Marko; Klarić, Martina; Zavašnik-Bergant, Tina; Gunčar, Gregor; Turk, Boris; Turk, Vito; Stoka, Veronika

2013-10-01

The contribution of individual cysteine cathepsins as positive mediators of programmed cell death is dependent on several factors, such as the type of stimuli, intensity and duration of the stimulus, and cell type involved. Of the eleven human cysteine cathepsins, cathepsin F is the only cathepsin that exhibits an extended N-terminal proregion, which contains a cystatin-like domain. We predicted that the wild-type human cathepsin F contains three natively disordered regions within the enzyme's propeptide and various amino acid stretches with high fibrillation propensity. Wild-type human cathepsin F and its N-terminally truncated forms, Ala(20)-Asp(484) (Δ(19)CatF), Pro(126)-Asp(484) (Δ(125)CatF), and Met(147)-Asp(484) (Δ(146)CatF) were cloned into the pcDNA3 vector and overexpressed in HEK 293T cells. Wild-type human cathepsin F displayed a clear vesicular labeling and colocalized with the LAMP2 protein, a lysosomal marker. However, all three N-terminally truncated forms of human cathepsin F were recovered as insoluble proteins, suggesting that the deletion of at least the signal peptides (Δ(19)CatF), results in protein aggregation. Noteworthy, they concentrated large perinuclear-juxtanuclear aggregates that accumulated within aggresome-like inclusions. These inclusions showed p62-positive immunoreactivity and were colocalized with the autophagy marker LC3B, but not with the LAMP2 protein. In addition, an approximately 2-3 fold increase in DEVDase activity was not sufficient to induce apoptotic cell death. These results suggested the clearance of the N-terminally truncated forms of human cathepsin F via the autophagy pathway, underlying its protective and prosurvival mechanisms. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

A Comparative Study of Behavior Problems among Left-Behind Children, Migrant Children and Local Children

Directory of Open Access Journals (Sweden)

Hongwei Hu

2018-04-01

Full Text Available This study aims to estimate the prevalence of behavioral problems among left-behind children, migrant children and local children in China, and to compare the risks of behavioral problems among the three types of children. Data on 4479 children aged 6–16 used in this study were from a survey conducted in China in 2017. The school-age version of the Children Behavior Checklist was used to measure children’s behavioral problems. Descriptive analysis, correlation analysis, and logistic regressions were conducted. The prevalence of behavioral problems was 18.80% and 13.59% for left-behind children and migrant children, respectively, both of which were higher than that of local children. Logistic regression analysis showed that after adjustments for individual and environmental variables, the likelihood of total, internalizing and externalizing behavior problems for left-behind children and migrant children were higher than those for local children; left-behind children had a higher likelihood of internalizing problems than externalizing problems, while migrant children had a higher prevalence of externalizing problems. Left-behind children had a higher prevalence of each specific syndrome than migrant and local children. Both individual and environmental factors were associated with child behavioral problems, and family migration may contribute to the increased risks. Left-behind and migrant children were more vulnerable than local children to behavioral problems.

Right Site, Wrong Route - Cannulating the Left Internal Jugular Vein.

Science.gov (United States)

Paik, Peter; Arukala, Sanjay K; Sule, Anupam A

2018-01-09

Central venous catheters are placed in approximately five million patients annually in the US. The preferred site of insertion is one with fewer risks and easier access. Although the right internal jugular vein is preferred, on occasion, the left internal jugular may have to be accessed. A patient was admitted for septic shock, cerebrovascular accident, and non-ST-segment elevation myocardial infarction. A central venous line was needed for antibiotic and vasopressor administration. Due to trauma from a fall to the right side and previously failed catheterization attempts at the left subclavian and femoral veins, the left internal jugular vein was accessed. On chest radiography for confirmation, the left internal jugular central venous catheter was seen projecting down the left paraspinal region. It did not take the expected course across the midline toward the right and into the superior vena cava (SVC). A review of a computed tomography (CT) scan of the chest with contrast done on a prior admission revealed a duplicated SVC on the left side that had not been reported in the original CT scan interpretation. A left-sided SVC is present in approximately 0.3% to 0.5% of the population, with 90% of these draining into the coronary sinus. During placements of central venous lines and pacemakers, irritation of the coronary sinus may result in hypotension, arrhythmia, myocardial ischemia, or cardiac arrest. A widened mediastinum can be an indication of a duplicated SVC. When attempting a left internal jugular vein central venous catheter placement, it is important to be aware of venous anomalies in order to prevent complications.

Hardware Design and Implementation of Fixed-Width Standard and Truncated 4×4, 6×6, 8×8 and 12×12-BIT Multipliers Using Fpga

Science.gov (United States)

Rais, Muhammad H.

2010-06-01

This paper presents Field Programmable Gate Array (FPGA) implementation of standard and truncated multipliers using Very High Speed Integrated Circuit Hardware Description Language (VHDL). Truncated multiplier is a good candidate for digital signal processing (DSP) applications such as finite impulse response (FIR) and discrete cosine transform (DCT). Remarkable reduction in FPGA resources, delay, and power can be achieved using truncated multipliers instead of standard parallel multipliers when the full precision of the standard multiplier is not required. The truncated multipliers show significant improvement as compared to standard multipliers. Results show that the anomaly in Spartan-3 AN average connection and maximum pin delay have been efficiently reduced in Virtex-4 device.

On the Minimax Value in the Scale Model with Truncated Data

OpenAIRE

Gajek, Leslaw

1988-01-01

Let $X$ be a positive random variable with Lebesgue density $f_\\theta(x)$, where $\\theta$ is the scale parameter, and let $Y$ be a positive random variable independent of $X$. We consider two models of truncation: the LHS model, where the data consist only of those observations of $X$ for which $X > Y$; and the RHS model, where the data consist of those observations of $X$ for which $X \\leq Y$. Consider the problem of estimating $\\theta^s, s \

Left-handedness and health

Directory of Open Access Journals (Sweden)

Milenković Sanja

2010-01-01

Full Text Available Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome, developmental disorders (autism, dislexia and sttutering and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about 'anomalous' cerebral domination, as a consequence of hormonal disbalance. .

[Left-handedness and health].

Science.gov (United States)

Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

2010-01-01

Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

[Left atrial function and left atrial appendage flow velocity in hypertrophic cardiomyopathy: comparison of patients with and without paroxysmal atrial fibrillation].

Science.gov (United States)

Akasaka, K; Kawashima, E; Shiokoshi, T; Ishii, Y; Hasebe, N; Kikuchi, K

1998-07-01

The involvement of left atrial (LA) appendage flow velocity in reduced left atrial function was investigated in 24 patients with hypertrophic cardiomyopathy, who retained sinus rhythm at the examination. Patients were divided into 11 with a history of paroxysmal atrial fibrillation [PAf(+)] and 13 without such history [PAf(-)]. Transthoracic echocardiography was performed to evaluate LA fractional shortening (LA%FS) and mean velocity of circumferential LA fiber shortening (LAmVcf), as contractile functions of the left atrium at the phase of active atrial contraction. Transesophageal echocardiographic Doppler examination was performed in all patients to measure the LA appendage velocity. In all patients, significant positive correlations were observed between the LA appendage velocity and LA%FS (r = 0.50, p fibrillation were significantly lower than in those without (0.84 +/- 0.15 vs 1.28 +/- 0.37 circ/sec, 44 +/- 12 vs 65 +/- 20 cm/sec, both p fibrillation. These results indicate that there is a close relationship between LA appendage velocity and LA contractile function in patients with hypertrophic cardiomyopathy with paroxysmal atrial fibrilation, and these patients have potential risk of cerebral infarction.

Significant correlation of P-wave parameters with left atrial volume index and left ventricular diastolic function.

Science.gov (United States)

Tsai, Wei-Chung; Lee, Kun-Tai; Wu, Ming-Tsang; Chu, Chih-Sheng; Lin, Tsung-Hsien; Hsu, Po-Chao; Su, Ho-Ming; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung

2013-07-01

The 12-lead electrocardiogram (ECG) is a commonly used tool to access left atrial enlargement, which is a marker of left ventricular diastolic dysfunction (LVDD). The aim of this study was to evaluate any association of the P-wave measurements in ECG with left atrial volume (LAV) index and LVDD. This study enrolled 270 patients. In this study, 4 ECG P-wave parameters corrected by heart rate, that is, corrected P-wave maximum duration (PWdurMaxC), corrected P-wave dispersion (PWdisperC), corrected P-wave area (PWareaC) and corrected mean P-wave duration (meanPWdurC), were measured. LAV and left ventricular diastolic parameters were measured from echocardiography. LVDD was defined as a pseudonormal or restrictive mitral inflow pattern. The 4 P-wave parameters were significantly correlated with the LAV index after adjusting for age, sex, diabetes, hypertension, coronary artery disease, body mass index and diastolic blood pressure in multivariate analysis. The standardized β coefficients of PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were 0.338, 0.298, 0.215 and 0.296, respectively. The 4 P-wave parameters were also significantly correlated with LVDD after multivariate logistic regression analysis. The odds ratios (95% confidence intervals) of PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were 1.03 (1.01-1.04), 1.02 (1.04-1.04), 1.04 (1.02-1.07) and 1.01 (1.00-1.02), respectively. This study demonstrated that PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were important determinants of the LAV index and LVDD. Therefore, screening patients by means of the 12-lead ECG may be helpful in identifying a high-risk group of increased LAV index and LVDD.

Algorithmic impediments filtration using the α-truncated mean method in resolver-to-digital converter

Directory of Open Access Journals (Sweden)

Gordiyenko V. I.

2009-02-01

Full Text Available A test diagram of the microcontroller-type resolver-to-digital converter and algorithms for impediments filtration therein are developed. Experimental verification of the α-truncated mean algorithm intended for the suppression of impulse and noise interference is conducted. The test results are given.

An analysis of longitudinal data with nonignorable dropout using the truncated multivariate normal distribution

NARCIS (Netherlands)

Jolani, Shahab

2014-01-01

For a vector of multivariate normal when some elements, but not necessarily all, are truncated, we derive the moment generating function and obtain expressions for the first two moments involving the multivariate hazard gradient. To show one of many applications of these moments, we then extend the

Cardiac arrhythmias and left ventricular hypertrophy in systemic hypertension

International Nuclear Information System (INIS)

Sultana, R.; Sultana, N.; Rashid, A.; Rasheed, S.Z.; Ahmed, M.; Ishaq, M.; Samad, A.

2010-01-01

Background: Hypertensive left ventricular hypertrophy (LVH) is associated with increased risk of arrhythmias and mortality. Objective was to investigate the prevalence of cardiac arrhythmias and LVH in systemic hypertension. Methods: In all subjects blood pressure was measured, electrocardiography and echocardiography was done. Holter monitoring and exercise test perform in certain cases. There were 500 hypertensive patients, 156 (31.2%) men and 344 (69%) women >30 years of age in the study. Among them 177 (35.4%) were diabetic, 224 (45%) were dyslipidemia, 188 (37.6%) were smokers, and 14 (3%) had homocysteinemia. Mean systolic BP (SBP) was 180 +- 20 mm Hg and diastolic BP (DBP) was 95 +- 12 in male and female patients. Left ventricular mass index (LVMI) was 119.2 +- 30 2 2gm/m in male while 103 +- 22 gm/m in female patients. Palpitation was seen in 126 (25%) male and 299 (59.8%) female patients. Atrial fibrillation was noted in 108 (21.6%) male and 125 (25%) female patients, 30 (6%) male and 82 (16.4%) female patients had atrial flutter. Ventricular tachycardia was noted in 37 (7.4%) male and 59 (11.8%) female patients. Holter monitoring showed significant premature ventricular contractions (PVC'S) in 109 (21.8%) male and 128 (25.69%) female patients while Holter showed atrial arrhythmias (APC'S) in 89 (17.8%) males and 119 (23.8%) females. Angiography findings diagnosed coronary artery disease in 119 (23.8%) with CAD male and 225 (45%) without CAD while 47 (9.4%) females presented with CAD and 109 (21.8%) without CAD. Conclusion: A significant association has been demonstrated between hypertension and arrhythmias. Diastolic dysfunction of the left ventricle, left atrial size and function, as well as LVH have been suggested as the underlying risk factors for supraventricular, ventricular arrhythmias and sudden death in hypertensives with LVH. (author)

Cardiac arrhythmias and left ventricular hypertrophy in systemic hypertension

Energy Technology Data Exchange (ETDEWEB)

Sultana, R; Sultana, N; Rashid, A; Rasheed, S Z; Ahmed, M; Ishaq, M; Samad, A [Karachi Institute of Heart Diseases, Karachi (Pakistan)

2010-10-15

Background: Hypertensive left ventricular hypertrophy (LVH) is associated with increased risk of arrhythmias and mortality. Objective was to investigate the prevalence of cardiac arrhythmias and LVH in systemic hypertension. Methods: In all subjects blood pressure was measured, electrocardiography and echocardiography was done. Holter monitoring and exercise test perform in certain cases. There were 500 hypertensive patients, 156 (31.2%) men and 344 (69%) women >30 years of age in the study. Among them 177 (35.4%) were diabetic, 224 (45%) were dyslipidemia, 188 (37.6%) were smokers, and 14 (3%) had homocysteinemia. Mean systolic BP (SBP) was 180 +- 20 mm Hg and diastolic BP (DBP) was 95 +- 12 in male and female patients. Left ventricular mass index (LVMI) was 119.2 +- 30 2 2gm/m in male while 103 +- 22 gm/m in female patients. Palpitation was seen in 126 (25%) male and 299 (59.8%) female patients. Atrial fibrillation was noted in 108 (21.6%) male and 125 (25%) female patients, 30 (6%) male and 82 (16.4%) female patients had atrial flutter. Ventricular tachycardia was noted in 37 (7.4%) male and 59 (11.8%) female patients. Holter monitoring showed significant premature ventricular contractions (PVC'S) in 109 (21.8%) male and 128 (25.69%) female patients while Holter showed atrial arrhythmias (APC'S) in 89 (17.8%) males and 119 (23.8%) females. Angiography findings diagnosed coronary artery disease in 119 (23.8%) with CAD male and 225 (45%) without CAD while 47 (9.4%) females presented with CAD and 109 (21.8%) without CAD. Conclusion: A significant association has been demonstrated between hypertension and arrhythmias. Diastolic dysfunction of the left ventricle, left atrial size and function, as well as LVH have been suggested as the underlying risk factors for supraventricular, ventricular arrhythmias and sudden death in hypertensives with LVH. (author)

A truncated accretion disk in the galactic black hole candidate source H1743-322

International Nuclear Information System (INIS)

Sriram, Kandulapati; Agrawal, Vivek Kumar; Rao, Arikkala Raghurama

2009-01-01

To investigate the geometry of the accretion disk in the source H1743-322, we have carried out a detailed X-ray temporal and spectral study using RXTE pointed observations. We have selected all data pertaining to the Steep Power Law (SPL) state during the 2003 outburst of this source. We find anti-correlated hard X-ray lags in three of the observations and the changes in the spectral and timing parameters (like the QPO frequency) confirm the idea of a truncated accretion disk in this source. Compiling data from similar observations of other sources, we find a correlation between the fractional change in the QPO frequency and the observed delay. We suggest that these observations indicate a definite size scale in the inner accretion disk (the radius of the truncated disk) and we explain the observed correlation using various disk parameters like Compton cooling time scale, viscous time scale etc. (research papers)

On the Computation of Optimal Monotone Mean-Variance Portfolios via Truncated Quadratic Utility

OpenAIRE

Ales Cerný; Fabio Maccheroni; Massimo Marinacci; Aldo Rustichini

2008-01-01

We report a surprising link between optimal portfolios generated by a special type of variational preferences called divergence preferences (cf. [8]) and optimal portfolios generated by classical expected utility. As a special case we connect optimization of truncated quadratic utility (cf. [2]) to the optimal monotone mean-variance portfolios (cf. [9]), thus simplifying the computation of the latter.

On how to define, understand and describe risk

International Nuclear Information System (INIS)

Aven, Terje

2010-01-01

The prevailing perspectives and definitions of risk, at least in the engineering community, are based on probabilities. In this paper we argue that such perspectives and definitions are too narrow. The probability component of the risk concept should be replaced by uncertainty. By jumping directly into probabilities, important uncertainty aspects could easily be overlooked or truncated. In the paper we point at several extended risk definitions, and a formal structure for the various perspectives and definitions is developed. Fundamental concepts such as second-order probabilities and uncertainties are discussed. Examples are provided showing the importance of the choice of risk perspective in a risk assessment and decision-making context. The examples cover offshore operations, security and market price risks.

A novel homozygous truncating GNAT1 mutation implicated in retinal degeneration.

Science.gov (United States)

Carrigan, Matthew; Duignan, Emma; Humphries, Pete; Palfi, Arpad; Kenna, Paul F; Farrar, G Jane

2016-04-01

The GNAT1 gene encodes the α subunit of the rod transducin protein, a key element in the rod phototransduction cascade. Variants in GNAT1 have been implicated in stationary night-blindness in the past, but unlike other proteins in the same pathway, it has not previously been implicated in retinitis pigmentosa. A panel of 182 retinopathy-associated genes was sequenced to locate disease-causing mutations in patients with inherited retinopathies. Sequencing revealed a novel homozygous truncating mutation in the GNAT1 gene in a patient with significant pigmentary disturbance and constriction of visual fields, a presentation consistent with retinitis pigmentosa. This is the first report of a patient homozygous for a complete loss-of-function GNAT1 mutation. The clinical data from this patient provide definitive evidence of retinitis pigmentosa with late onset in addition to the lifelong night-blindness that would be expected from a lack of transducin function. These data suggest that some truncating GNAT1 variants can indeed cause a recessive, mild, late-onset retinal degeneration in human beings rather than just stationary night-blindness as reported previously, with notable similarities to the phenotype of the Gnat1 knockout mouse. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Quasi-SU(3) truncation scheme for even-even sd-shell nuclei

Energy Technology Data Exchange (ETDEWEB)

Vargas, C.E. E-mail: cvargas@fis.cinvestav.mx; Hirsch, J.G. E-mail: hirsch@nuclecu.unam.mx; Draayer, J.P. E-mail: draayer@lsu.edu

2001-07-30

The quasi-SU(3) symmetry was uncovered in full pf and sdg shell-model calculations for both even-even and odd-even nuclei. It manifests itself through a dominance of single-particle and quadrupole-quadrupole terms in a Hamiltonian used to describe well-deformed nuclei. A practical consequence of the quasi-SU(3) symmetry is an efficient basis truncation scheme. In [C.E. Vargas et al., Phys. Rev. C 58 (1998) 1488] it is shown that when this type of Hamiltonian is diagonalized in an SU(3) basis, only a few irreducible representations (irreps) of SU(3) are needed to describe the yrast band, the leading S=0 irrep augmented with the leading S=1 irreps in the proton and neutron subspaces. In the present article the quasi-SU(3) truncation scheme is used, in conjunction with a 'realistic but schematic' Hamiltonian that includes the most important multipole terms, to describe the energy spectra and B(E2) transition strengths of {sup 20,22}Ne, {sup 24}Mg and {sup 28}Si. The effect of the size of the Hilbert space on both sets of observables is discussed, as well as the structure of the yrast band and the importance of the various terms in the Hamiltonian. The limitations of the model are explicitly discussed.

Ascending-ramp biphasic waveform has a lower defibrillation threshold and releases less troponin I than a truncated exponential biphasic waveform.

Science.gov (United States)

Huang, Jian; Walcott, Gregory P; Ruse, Richard B; Bohanan, Scott J; Killingsworth, Cheryl R; Ideker, Raymond E

2012-09-11

We tested the hypothesis that the shape of the shock waveform affects not only the defibrillation threshold but also the amount of cardiac damage. Defibrillation thresholds were determined for 11 waveforms-3 ascending-ramp waveforms, 3 descending-ramp waveforms, 3 rectilinear first-phase biphasic waveforms, a Gurvich waveform, and a truncated exponential biphasic waveform-in 6 pigs with electrodes in the right ventricular apex and superior vena cava. The ascending, descending, and rectilinear waveforms had 4-, 8-, and 16-millisecond first phases and a 3.5-millisecond rectilinear second phase that was half the voltage of the first phase. The exponential biphasic waveform had a 60% first-phase and a 50% second-phase tilt. In a second study, we attempted to defibrillate after 10 seconds of ventricular fibrillation with a single ≈30-J shock (6 pigs successfully defibrillated with 8-millisecond ascending, 8-millisecond rectilinear, and truncated exponential biphasic waveforms). Troponin I blood levels were determined before and 2 to 10 hours after the shock. The lowest-energy defibrillation threshold was for the 8-milliseconds ascending ramp (14.6±7.3 J [mean±SD]), which was significantly less than for the truncated exponential (19.6±6.3 J). Six hours after shock, troponin I was significantly less for the ascending-ramp waveform (0.80±0.54 ng/mL) than for the truncated exponential (1.92±0.47 ng/mL) or the rectilinear waveform (1.17±0.45 ng/mL). The ascending ramp has a significantly lower defibrillation threshold and at ≈30 J causes 58% less troponin I release than the truncated exponential biphasic shock. Therefore, the shock waveform affects both the defibrillation threshold and the amount of cardiac damage.

Cardiac risk index as a simple geometric indicator to select patients for the heart-sparing radiotherapy of left-sided breast cancer

International Nuclear Information System (INIS)

Sung, KiHoon; Choi, Young Eun; Lee, Kyu Chan

2017-01-01

This is a dosimetric study to identify a simple geometric indicator to discriminate patients who meet the selection criterion for heart-sparing radiotherapy (RT). The authors proposed a cardiac risk index (CRI), directly measurable from the CT images at the time of scanning. Treatment plans were regenerated using the CT data of 312 consecutive patients with left-sided breast cancer. Dosimetric analysis was performed to estimate the risk of cardiac mortality using cardiac dosimetric parameters, such as the relative heart volumes receiving ≥25 Gy (heart V 25 ). For each CT data set, in-field heart depth (HD) and in-field heart width (HW) were measured to generate the geometric parameters, including maximum HW (HW max ) and maximum HD (HD max ). Seven geometric parameters were evaluated as candidates for CRI. Receiver operating characteristic (ROC) curve analyses were used to examine the overall discriminatory power of the geometric parameters to select high-risk patients (heart V 25 ≥ 10%). Seventy-one high-risk (22.8%) and 241 low-risk patients (77.2%) were identified by dosimetric analysis. The geometric and dosimetric parameters were significantly higher in the high-risk group. Heart V 25 showed the strong positive correlations with all geometric parameters examined (r > 0.8, p < 0.001). The product of HD max and HW max (CRI) revealed the largest area under the curve (AUC) value (0.969) and maintained 100% sensitivity and 88% specificity at the optimal cut-off value of 14.58 cm 2 . Cardiac risk index proposed as a simple geometric indicator to select high-risk patients provides useful guidance for clinicians considering optimal implementation of heart-sparing RT.

New strict left bundle branch block criteria reflect left ventricular activation differences

DEFF Research Database (Denmark)

Emerek, Kasper Janus Grønn; Risum, Niels; Hjortshøj, Søren Pihlkjær

2015-01-01

AIMS: Pacing lead electrical delays and strict left bundle branch block (LBBB) criteria were assessed against cardiac resynchronization therapy (CRT) outcome. METHODS: Forty-nine patients with LBBB and QRS duration >130 milliseconds underwent CRT-implantation. Sensed right ventricular to left ven....... CONCLUSION: Interventricular electrical delay predicts left ventricular remodeling after CRT and new, strict ECG criteria of LBBB are superior in predicting remodeling.......AIMS: Pacing lead electrical delays and strict left bundle branch block (LBBB) criteria were assessed against cardiac resynchronization therapy (CRT) outcome. METHODS: Forty-nine patients with LBBB and QRS duration >130 milliseconds underwent CRT-implantation. Sensed right ventricular to left...... ventricular electrical delay (RV-LV-IED) was measured. Response to CRT was defined as ≥15% decrease in left ventricular end-systolic volume. RESULTS: Eighteen of 20 (90%) patients with non-ischemic dilated cardiomyopathy (DCM) and 18 of 29 (62%) with ischemic heart disease (IHD) responded to CRT, p

A comparative analysis of suicide attempts in left-behind children and non-left-behind children in rural China.

Directory of Open Access Journals (Sweden)

Hongjuan Chang

Full Text Available To estimate the prevalence of suicide attempts and explore the shared and unique factors influencing suicide risk in left-behind children (LBC and non-left-behind children (NLBC in rural China, this study collected data using a multi-stage cluster random sampling method from 13,952 children including 6,034 LBC and 7,918 NLBC. Sociodemographic characteristics, suicide attempts, neglect and physical abuse, negative life events, and loneliness were measured by self-reported questionnaires. Data were analyzed using logistic regression models. Gender and mother's education level were unique influential factors for NLBC while family structure type was a unique influential factor for LBC. The study provides two novel findings regarding NLBC specifically: 1. Children with optimal family socioeconomic status are more likely to report suicide attempts (odds ratio OR = 1than are those in the general children population, OR 0.52 (95% CI: 0.39-0.70, and 2. Children with higher mother's education level are subject to higher suicide rates in high school, OR 1.67 (95% CI: 1.13-2.46, and post-secondary education, OR 2.14 (95% CI: 1.37-3.37. The unique characteristics of LBC and NLBC in China suggest that investigating risk factors and determining the factors that might be targeted in intervention programs are urgently needed currently.

A computational approach for a fluid queue driven by a truncated birth-death process

NARCIS (Netherlands)

Lenin, R.B.; Parthasarathy, P.R.

1999-01-01

In this paper, we consider a fluid queue driven by a truncated birth-death process with general birth and death rates. We find the equilibrium distribution of the content of the fluid buffer by computing the eigenvalues and eigenvectors of an associated real tridiagonal matrix. We provide efficient

Left ventricular rupture postmitral valve replacement: Surviving a catastrophe

Directory of Open Access Journals (Sweden)

Samarjit Bisoyi

2015-01-01

Full Text Available One of the dreaded mechanical complications of mitral valve replacement (MVR is rupture of the left ventricle (LV. This report describes the early diagnosis and successful repair of rupture of posterior wall of LV in an elderly patient who underwent MVR. We have discussed the risk factors and perioperative issues implicated in such complication. The anesthesiologist as an intra-operative echocardiographer can aid in identifying the patient at risk. Though important surgical steps are necessary to prevent the complication; nonetheless, the anesthesiologist needs to take key measures in the perioperative period.

Truncated Levy flights and agenda-based mobility are useful for the assessment of personal human exposure

International Nuclear Information System (INIS)

Schlink, Uwe; Ragas, Ad M.J.

2011-01-01

Receptor-oriented approaches can assess the individual-specific exposure to air pollution. In such an individual-based model we analyse the impact of human mobility to the personal exposure that is perceived by individuals simulated in an exemplified urban area. The mobility models comprise random walk (reference point mobility, RPM), truncated Levy flights (TLF), and agenda-based walk (RPMA). We describe and review the general concepts and provide an inter-comparison of these concepts. Stationary and ergodic behaviour are explained and applied as well as performance criteria for a comparative evaluation of the investigated algorithms. We find that none of the studied algorithm results in purely random trajectories. TLF and RPMA prove to be suitable for human mobility modelling, because they provide conditions for very individual-specific trajectories and exposure. Suggesting these models we demonstrate the plausibility of their results for exposure to air-borne benzene and the combined exposure to benzene and nonane. - Highlights: → Human exposure to air pollutants is influenced by a person's movement in the urban area. → We provide a simulation study of approaches to modelling personal exposure. → Agenda-based models and truncated Levy flights are recommended for exposure assessment. → The procedure is demonstrated for benzene exposure in an urban region. - Truncated Levy flights and agenda-based mobility are useful for the assessment of personal human exposure.

Neurodegeneration caused by expression of human truncated tau leads to progressive neurobehavioural impairment in transgenic rats.

Science.gov (United States)

Hrnkova, Miroslava; Zilka, Norbert; Minichova, Zuzana; Koson, Peter; Novak, Michal

2007-01-26

Human truncated tau protein is an active constituent of the neurofibrillary degeneration in sporadic Alzheimer's disease. We have shown that modified tau protein, when expressed as a transgene in rats, induced AD characteristic tau cascade consisting of tau hyperphosphorylation, formation of argyrophilic tangles and sarcosyl-insoluble tau complexes. These pathological changes led to the functional impairment characterized by a variety of neurobehavioural symptoms. In the present study we have focused on the behavioural alterations induced by transgenic expression of human truncated tau. Transgenic rats underwent a battery of behavioural tests involving cognitive- and sensorimotor-dependent tasks accompanied with neurological assessment at the age of 4.5, 6 and 9 months. Behavioural examination of these rats showed altered spatial navigation in Morris water maze resulting in less time spent in target quadrant (popen field was not influenced by transgene expression. However beam walking test revealed that transgenic rats developed progressive sensorimotor disturbances related to the age of tested animals. The disturbances were most pronounced at the age of 9 months (p<0.01). Neurological alterations indicating impaired reflex responses were other added features of behavioural phenotype of this novel transgenic rat. These results allow us to suggest that neurodegeneration, caused by the non-mutated human truncated tau derived from sporadic human AD, result in the neuronal dysfunction consequently leading to the progressive neurobehavioural impairment.

Seniority truncation in an equations-of-motion approach to the shell model

International Nuclear Information System (INIS)

Covello, A.; Andreozzi, F.; Gargano, A.; Porrino, A.

1989-01-01

This paper presents an equations-of-motion method for treating shell-model problems within the framework of the seniority scheme. This method can be applied at many levels of approximation and represents therefore a valuable tool to further reduce seniority truncated shell-model spaces. To show its practical value the authors report some results of an extensive study of the N = 82 isotones which is currently under way

Loads experiments study on two-story RC box and truncated conical walls

International Nuclear Information System (INIS)

Asega, H.; Iizuka, S.; Kurihara, I.; Kubo, T.

1987-01-01

The failure modes of the two specimens were the sliding shear failure. The two specimens showed almost equal deformation at the maximum shear strength. The ratio of the flexural deformation in the deformation of the truncated conical was larger than that of the box wall. The ratio of the shear deformation in the deformation of the two-story RC box wall was larger than that of the flexural deformation. (orig./HP)

An ABCA1 truncation shows no dominant negative effect in a familial hypoalphalipoproteinemia pedigree with three ABCA1 mutations

Energy Technology Data Exchange (ETDEWEB)

Sorrenson, Brie; Suetani, Rachel J. [Department of Biochemistry, University of Otago, Dunedin (New Zealand); Bickley, Vivienne M.; George, Peter M. [Clinical Biochemistry, Canterbury Health Laboratories, Christchurch (New Zealand); Williams, Michael J.A. [Department of Medicine, University of Otago, Dunedin (New Zealand); Scott, Russell S. [Lipid and Diabetes Research Group, Christchurch Hospital (New Zealand); McCormick, Sally P.A., E-mail: sally.mccormick@otago.ac.nz [Department of Biochemistry, University of Otago, Dunedin (New Zealand)

2011-06-10

Highlights: {yields} Characterisation of an ABCA1 truncation mutant, C978fsX988, in a pedigree with three ABCA1 mutations. {yields} Functional analysis of C978fsX988 in patient fibroblasts and HEK 293 cells shows no cholesterol efflux function. {yields} Allele-specific quantification shows C978fsX988 not expressed at mRNA level in fibroblasts. {yields} Unlike other ABCA1 truncations, C978fsX988 mutant shows no dominant negative effect at mRNA or protein level. -- Abstract: The ATP binding cassette transporter (ABCA1) A1 is a key determinant of circulating high density lipoprotein cholesterol (HDL-C) levels. Mutations in ABCA1 are a major genetic contributor to low HDL-C levels within the general population. Following the finding of three different ABCA1 mutations, p.C978fsX988, p.T1512M and p.N1800H in a subject with hypoalphalipoproteinemia, we aimed to establish whether the p.C978fsX988 truncation exerted a dominant negative effect on the full-length ABCA1 alleles within family members as has been reported for other ABCA1 truncations. Characterisation of the p.C978fsX988 mutant in transfected HEK 293 cells showed it to be expressed as a GFP fusion protein but lacking in cholesterol efflux function. This was in keeping with results from cholesterol efflux assays in the fibroblasts of p.C978fsX988 carriers which also showed impaired efflux. Allele- specific quantification of p.C978fsX988 mRNA and analysis of ABCA1 protein levels in the fibroblasts of p.C978fsX988 heterozygotes showed negligible levels of mRNA and protein expression. There was no evidence of a dominant negative effect on wildtype or p.N1800H protein levels. We conclude that in the case of the p.C978fsX988 truncated mutant a lack of expression precludes it from having a dominant negative effect.

Vortex breakdown in a truncated conical bioreactor

Energy Technology Data Exchange (ETDEWEB)

Balci, Adnan; Brøns, Morten [DTU Compute, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Herrada, Miguel A [E.S.I, Universidad de Sevilla, Camino de los Descubrimientos s/n, E-41092 (Spain); Shtern, Vladimir N, E-mail: mobr@dtu.dk [Shtern Research and Consulting, Houston, TX 77096 (United States)

2015-12-15

This numerical study explains the eddy formation and disappearance in a slow steady axisymmetric air–water flow in a vertical truncated conical container, driven by the rotating top disk. Numerous topological metamorphoses occur as the water height, H{sub w}, and the bottom-sidewall angle, α, vary. It is found that the sidewall convergence (divergence) from the top to the bottom stimulates (suppresses) the development of vortex breakdown (VB) in both water and air. At α = 60°, the flow topology changes eighteen times as H{sub w} varies. The changes are due to (a) competing effects of AMF (the air meridional flow) and swirl, which drive meridional motions of opposite directions in water, and (b) feedback of water flow on AMF. For small H{sub w}, the AMF effect dominates. As H{sub w} increases, the swirl effect dominates and causes VB. The water flow feedback produces and modifies air eddies. The results are of fundamental interest and can be relevant for aerial bioreactors. (paper)

Vortex breakdown in a truncated conical bioreactor

International Nuclear Information System (INIS)

Balci, Adnan; Brøns, Morten; Herrada, Miguel A; Shtern, Vladimir N

2015-01-01

This numerical study explains the eddy formation and disappearance in a slow steady axisymmetric air–water flow in a vertical truncated conical container, driven by the rotating top disk. Numerous topological metamorphoses occur as the water height, H w , and the bottom-sidewall angle, α, vary. It is found that the sidewall convergence (divergence) from the top to the bottom stimulates (suppresses) the development of vortex breakdown (VB) in both water and air. At α = 60°, the flow topology changes eighteen times as H w varies. The changes are due to (a) competing effects of AMF (the air meridional flow) and swirl, which drive meridional motions of opposite directions in water, and (b) feedback of water flow on AMF. For small H w , the AMF effect dominates. As H w increases, the swirl effect dominates and causes VB. The water flow feedback produces and modifies air eddies. The results are of fundamental interest and can be relevant for aerial bioreactors. (paper)

Effect of truncated glucagon-like peptide-1 [proglucagon-(78-107) amide] on endocrine secretion from pig pancreas, antrum, and nonantral stomach

DEFF Research Database (Denmark)

Orskov, C; Holst, J J; Nielsen, O V

1988-01-01

We studied the effect of truncated glucagon-like peptide-1 [naturally occurring GLP-1; proglucagon-(78-107) amide], a potent insulinotropic peptide from the pig ileum, on endocrine and exocrine secretion of potential gastrointestinal target organs using isolated perfused preparations of the porcine...... pancreas, antrum, and nonantral part of the stomach. Truncated GLP-1 significantly increased somatostatin secretion from the pancreas at 10(-10) mol/liter and more than doubled the secretion at 10(-9) mol/liter, but had no effect on either somatostatin or gastrin secretion from the antrum...... or on somatostatin secretion from the nonantral stomach in concentrations up to 10(-8) mol/liter. Insulin secretion from the pancreas (with 7 mmol/liter glucose in the perfusate) increased 2-fold with truncated GLP-1 at 10(-10) mol/liter and almost 5-fold at 10(-9) mol/liter. Pancreatic glucagon secretion...

CONVERGENCE OF THE FRACTIONAL PARTS OF THE RANDOM VARIABLES TO THE TRUNCATED EXPONENTIAL DISTRIBUTION

Directory of Open Access Journals (Sweden)

Bogdan Gheorghe Munteanu

2013-01-01

Full Text Available Using the stochastic approximations, in this paper it was studiedthe convergence in distribution of the fractional parts of the sum of random variables to the truncated exponential distribution with parameter lambda. This fact is feasible by means of the Fourier-Stieltjes sequence (FSS of the random variable.

Stopping randomized trials early for benefit: a protocol of the Study Of Trial Policy Of Interim Truncation-2 (STOPIT-2)

Science.gov (United States)

Briel, Matthias; Lane, Melanie; Montori, Victor M; Bassler, Dirk; Glasziou, Paul; Malaga, German; Akl, Elie A; Ferreira-Gonzalez, Ignacio; Alonso-Coello, Pablo; Urrutia, Gerard; Kunz, Regina; Culebro, Carolina Ruiz; da Silva, Suzana Alves; Flynn, David N; Elamin, Mohamed B; Strahm, Brigitte; Murad, M Hassan; Djulbegovic, Benjamin; Adhikari, Neill KJ; Mills, Edward J; Gwadry-Sridhar, Femida; Kirpalani, Haresh; Soares, Heloisa P; Elnour, Nisrin O Abu; You, John J; Karanicolas, Paul J; Bucher, Heiner C; Lampropulos, Julianna F; Nordmann, Alain J; Burns, Karen EA; Mulla, Sohail M; Raatz, Heike; Sood, Amit; Kaur, Jagdeep; Bankhead, Clare R; Mullan, Rebecca J; Nerenberg, Kara A; Vandvik, Per Olav; Coto-Yglesias, Fernando; Schünemann, Holger; Tuche, Fabio; Chrispim, Pedro Paulo M; Cook, Deborah J; Lutz, Kristina; Ribic, Christine M; Vale, Noah; Erwin, Patricia J; Perera, Rafael; Zhou, Qi; Heels-Ansdell, Diane; Ramsay, Tim; Walter, Stephen D; Guyatt, Gordon H

2009-01-01

Background Randomized clinical trials (RCTs) stopped early for benefit often receive great attention and affect clinical practice, but pose interpretational challenges for clinicians, researchers, and policy makers. Because the decision to stop the trial may arise from catching the treatment effect at a random high, truncated RCTs (tRCTs) may overestimate the true treatment effect. The Study Of Trial Policy Of Interim Truncation (STOPIT-1), which systematically reviewed the epidemiology and reporting quality of tRCTs, found that such trials are becoming more common, but that reporting of stopping rules and decisions were often deficient. Most importantly, treatment effects were often implausibly large and inversely related to the number of the events accrued. The aim of STOPIT-2 is to determine the magnitude and determinants of possible bias introduced by stopping RCTs early for benefit. Methods/Design We will use sensitive strategies to search for systematic reviews addressing the same clinical question as each of the tRCTs identified in STOPIT-1 and in a subsequent literature search. We will check all RCTs included in each systematic review to determine their similarity to the index tRCT in terms of participants, interventions, and outcome definition, and conduct new meta-analyses addressing the outcome that led to early termination of the tRCT. For each pair of tRCT and systematic review of corresponding non-tRCTs we will estimate the ratio of relative risks, and hence estimate the degree of bias. We will use hierarchical multivariable regression to determine the factors associated with the magnitude of this ratio. Factors explored will include the presence and quality of a stopping rule, the methodological quality of the trials, and the number of total events that had occurred at the time of truncation. Finally, we will evaluate whether Bayesian methods using conservative informative priors to "regress to the mean" overoptimistic tRCTs can correct observed

Stopping randomized trials early for benefit: a protocol of the Study Of Trial Policy Of Interim Truncation-2 (STOPIT-2

Directory of Open Access Journals (Sweden)

Mullan Rebecca J

2009-07-01

Full Text Available Abstract Background Randomized clinical trials (RCTs stopped early for benefit often receive great attention and affect clinical practice, but pose interpretational challenges for clinicians, researchers, and policy makers. Because the decision to stop the trial may arise from catching the treatment effect at a random high, truncated RCTs (tRCTs may overestimate the true treatment effect. The Study Of Trial Policy Of Interim Truncation (STOPIT-1, which systematically reviewed the epidemiology and reporting quality of tRCTs, found that such trials are becoming more common, but that reporting of stopping rules and decisions were often deficient. Most importantly, treatment effects were often implausibly large and inversely related to the number of the events accrued. The aim of STOPIT-2 is to determine the magnitude and determinants of possible bias introduced by stopping RCTs early for benefit. Methods/Design We will use sensitive strategies to search for systematic reviews addressing the same clinical question as each of the tRCTs identified in STOPIT-1 and in a subsequent literature search. We will check all RCTs included in each systematic review to determine their similarity to the index tRCT in terms of participants, interventions, and outcome definition, and conduct new meta-analyses addressing the outcome that led to early termination of the tRCT. For each pair of tRCT and systematic review of corresponding non-tRCTs we will estimate the ratio of relative risks, and hence estimate the degree of bias. We will use hierarchical multivariable regression to determine the factors associated with the magnitude of this ratio. Factors explored will include the presence and quality of a stopping rule, the methodological quality of the trials, and the number of total events that had occurred at the time of truncation. Finally, we will evaluate whether Bayesian methods using conservative informative priors to "regress to the mean" overoptimistic t

Computing the Moments of Order Statistics from Truncated Pareto Distributions Based on the Conditional Expectation

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Gökhan Gökdere

2014-05-01

Full Text Available In this paper, closed form expressions for the moments of the truncated Pareto order statistics are obtained by using conditional distribution. We also derive some results for the moments which will be useful for moment computations based on ordered data.

Pulmonary Hypertension with Left Heart Disease: Prevalence, Temporal Shifts in Etiologies and Outcome.

Science.gov (United States)

Weitsman, Tatyana; Weisz, Giora; Farkash, Rivka; Klutstein, Marc; Butnaru, Adi; Rosenmann, David; Hasin, Tal

2017-11-01

Pulmonary hypertension has many causes. While it is conventionally thought that the most prevalent is left heart disease, little information about its proportion, causes, and implications on outcome is available. Between 1993 and 2015, 12,115 of 66,949 (18%) first adult transthoracic echocardiograms were found to have tricuspid incompetence gradient ≥40 mm Hg, a pulmonary hypertension surrogate. Left heart disease was identified in 8306 (69%) and included valve malfunction in 4115 (49%), left ventricular systolic dysfunction in 2557 (31%), and diastolic dysfunction in 1776 (21%). Patients with left heart disease, as compared with those without left heart disease, were of similar age, fewer were females (50% vs 63% P pulmonary hypertension with left heart disease. Independent predictors of mortality were age (hazard ratio [HR] 1.05; 95% CI, 1.04-1.05; P pulmonary hypertension but without left heart disease (HR 1.30; 95% CI, 1.20-1.42 and HR 1.44; 95% CI, 1.33-1.55, respectively; P Pulmonary hypertension was found to be associated with left heart disease in 69% of patients. Among these patients, valve malfunction and diastolic dysfunction emerged as prominent causes. Left ventricular dysfunction carries additional risk to patients with pulmonary hypertension. Copyright © 2017 Elsevier Inc. All rights reserved.

Anterior Myocardial Territory May Replace the Heart as Organ at Risk in Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer

International Nuclear Information System (INIS)

Tan Wenyong; Liu Dong; Xue Chenbin; Xu Jiaozhen; Li Beihui; Chen Zhengwang; Hu Desheng; Wang Xionghong

2012-01-01

Purpose: We investigated whether the heart could be replaced by the anterior myocardial territory (AMT) as the organ at risk (OAR) in intensity-modulated radiotherapy (IMRT) of the breast for patients with left-sided breast cancer. Methods and Materials: Twenty-three patients with left-sided breast cancer who received postoperative radiation after breast-conserving surgery were studied. For each patient, we generated five IMRT plans including heart (H), left ventricle (LV), AMT, LV+AMT, and H+LV as the primary OARs, respectively, except both lungs and right breast, which corresponded to IMRT(H), IMRT(LV), IMRT(AMT), IMRT(LV+AMT), and IMRT(H+LV). For the planning target volumes and OARs, the parameters of dose–volume histograms were compared. Results: The homogeneity index, conformity index, and coverage index were not compromised significantly in IMRT(AMT), IMRT(LV) and IMRT(LV+ AMT), respectively, when compared with IMRT(H). The mean dose to the heart, LV, and AMT decreased 5.3–21.5% (p < 0.05), 19.9–29.5% (p < 0.05), and 13.3–24.5% (p < 0.05), respectively. Similarly, the low (e.g., V5%), middle (e.g., V20%), and high (e.g., V30%) dose-volume of the heart, LV, and AMT decreased with different levels. The mean dose and V10% of the right lung increased by 9.2% (p < 0.05) and 27.6% (p < 0.05), respectively, in IMRT(LV), and the mean dose and V5% of the right breast decreased significantly in IMRT(AMT) and IMRT(LV+AMT). IMRT(AMT) was the preferred plan and was then compared with IMRT(H+LV); the majority of dose–volume histogram parameters of OARs including the heart, LV, AMT, both lungs, and the right breast were not statistically different. However, the low dose-volume of LV increased and the middle dose-volume decreased significantly (p < 0.05) in IMRT(AMT). Also, those of the right lung (V10%, V15%) and right breast (V5%, V10%) decreased significantly (p < 0.05). Conclusions: The AMT may replace the heart as the OAR in left-sided breast IMRT after breast

Effect of Synthetic Truncated Apolipoprotein C-I Peptide on Plasma Lipoprotein Cholesterol in Nonhuman Primates

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Rampratap S. Kushwaha

2004-01-01

Full Text Available The present studies were conducted to determine whether a synthetic truncated apoC-I peptide that inhibits CETP activity in baboons would raise plasma HDL cholesterol levels in nonhuman primates with low HDL levels. We used 2 cynomolgus monkeys and 3 baboons fed a cholesterol- and fat-enriched diet. In cynomolgus monkeys, we injected synthetic truncated apoC-I inhibitor peptide at a dose of 20 mg/kg and, in baboons, at doses of 10, 15, and 20 mg/kg at weekly intervals. Blood samples were collected 3 times a week and VLDL + LDL and HDL cholesterol concentrations were measured. In cynomolgus monkeys, administration of the inhibitor peptide caused a rapid decrease in VLDL + LDL cholesterol concentrations (30%–60% and an increase in HDL cholesterol concentrations (10%–20%. VLDL + LDL cholesterol concentrations returned to baseline levels in approximately 15 days. In baboons, administration of the synthetic inhibitor peptide caused a decrease in VLDL + LDL cholesterol (20%–60% and an increase in HDL cholesterol (10%–20%. VLDL + LDL cholesterol returned to baseline levels by day 21, whereas HDL cholesterol concentrations remained elevated for up to 26 days. ApoA-I concentrations increased, whereas apoE and triglyceride concentrations decreased. Subcutaneous and intravenous administrations of the inhibitor peptide had similar effects on LDL and HDL cholesterol concentrations. There was no change in body weight, food consumption, or plasma IgG levels of any baboon during the study. These studies suggest that the truncated apoC-I peptide can be used to raise HDL in humans.

Regression of electrocardiographic left ventricular hypertrophy during antihypertensive therapy and reduction in sudden cardiac death: the LIFE Study

DEFF Research Database (Denmark)

Wachtell, Kristian; Okin, Peter M; Olsen, Michael H

2007-01-01

BACKGROUND: Sudden cardiac death (SCD) occurs more often in patients with ECG left ventricular (LV) hypertrophy. However, whether LV hypertrophy regression is associated with a reduced risk of SCD remains unclear. METHODS AND RESULTS: The Losartan Intervention for End Point Reduction in Hypertens......BACKGROUND: Sudden cardiac death (SCD) occurs more often in patients with ECG left ventricular (LV) hypertrophy. However, whether LV hypertrophy regression is associated with a reduced risk of SCD remains unclear. METHODS AND RESULTS: The Losartan Intervention for End Point Reduction...... risk of SCD independently of treatment modality, blood pressure reduction, prevalent coronary heart disease, and other cardiovascular risk factors in hypertensive patients with LV hypertrophy. Udgivelsesdato: 2007-Aug-14...

Dosimetric Comparison of Intensity-Modulated Radiotherapy Plans, With or Without Anterior Myocardial Territory and Left Ventricle as Organs at Risk, in Early-Stage Left-Sided Breast Cancer Patients

International Nuclear Information System (INIS)

Tan Wenyong; Wang Xiaohong; Qiu Dasheng; Liu Dong; Jia Shaohui; Zeng Fanyu; Chen Zhengwang; Li Beihui; Xu Jiaozhen; Wei Lai; Hu Desheng

2011-01-01

Purpose: We evaluated heart sparing using an intensity-modulated radiotherapy (IMRT) plan with the left ventricle (LV) and/or the anterior myocardial territory (AMT) as additional organs at risk (OARs). Methods and Materials: A total of 10 patients with left-sided breast cancer were selected for dosimetric planning. Both lungs, the right breast, heart, LV, and AMT were defined as OARs. We generated one tangential field plan and four IMRT plans for each patient. We examined the dose–volume histogram parameters of the planning target volume and OARs. Results: Compared with the tangential field plan, the mean dose to the heart in the IMRT plans did not show significant differences; however, the dose to the AMT and LV decreased by 18.7–45.4% and 10.8–37.4%, respectively. The maximal dose to the heart decreased by 18.6–35.3%, to the AMT by 22.0–45.1%, and to the LV by 23.5–45.0%, And the relative volumes of the heart (V ≥12 ), AMT (V >11 ) and LV (V >10 ) decreased significantly with different levels, respectively. The volume of the heart, AMT, LV, both lungs, and right breast receiving ≥5 Gy showed a significant increase. Compared with the IMRT (H) plan, the mean dose to the heart, AMT, and LV decreased by 17.5–21.5%, 25.2–29.8%, and 22.8–29.8% and the maximal dose by 13.6–20.6%, 23.1–29.6%, and 17.3–29.1%, respectively. The IMRT plans for both lungs and the right breast showed no significant differences. Conclusions: The IMRT plans with the addition of the AMT and/or LV as OARs considerably increased heart sparing. We recommend including the LV as an additional OAR in such plans.

Association between circulating fibroblast growth factor 23, α-Klotho, and the left ventricular ejection fraction and left ventricular mass in cardiology inpatients.

Directory of Open Access Journals (Sweden)

Kensaku Shibata

Full Text Available BACKGROUND: Fibroblast growth factor 23 (FGF23, with its co-receptor Klotho, plays a crucial role in phosphate metabolism. Several recent studies suggested that circulating FGF23 and α-Klotho concentrations might be related to cardiovascular abnormalities in patients with advanced renal failure. PURPOSE: Using data from 100 cardiology inpatients who were not undergoing chronic hemodialysis, the association of circulating levels of FGF23, α-Klotho, and other calcium-phosphate metabolism-related parameters with the left ventricular ejection fraction (LVEF and left ventricular mass (LVM was analyzed. METHODS AND RESULTS: LVEF was measured using the modified Simpson method for apical 4-chamber LV images and the LVM index (LVMI was calculated by dividing the LVM by body surface area. Univariate analysis showed that log transformed FGF23, but not that of α-Klotho, was significantly associated with LVEF and LVMI with a standardized beta of -0.35 (P<0.001 and 0.26 (P<0.05, respectively. After adjusting for age, sex, estimated glomerular filtration rate, and serum concentrations of intact parathyroid hormone, and 25-hydroxyvitamin D as covariates into the statistical model, log-transformed FGF23 was found to be a statistically positive predictor for decreased left ventricular function and left ventricular hypertrophy. CONCLUSIONS: In cardiology department inpatients, circulating FGF23 concentrations were found to be associated with the left ventricular mass and LVEF independent of renal function and other calcium-phosphate metabolism-related parameters. Whether modulation of circulating FGF23 levels would improve cardiac outcome in such a high risk population awaits further investigation.

[Tourette syndrome and reading disorder in a boy with left parietofrontal tract disruption].

Science.gov (United States)

Martín Fernández-Mayoralas, D; Fernández-Jaén, A; Gómez Herrera, J J; Jiménez de la Peña, M

2014-01-01

We present the case of a nine-year-old boy with Tourette syndrome and reading disorder with a history of a severe infectious process in the late neonatal period. Brain MRI showed a left parietal malacotic cavity and diffusion tensor imaging and tractography showed a striking disruption of the white matter bundle that joins the left parietal region with the ipsilateral frontal region with involvement of the left superior longitudinal fasciculus and of the left arcuate fasciculus. Although Tourette syndrome and reading disorder are fundamentally hereditary neuropsychiatric disorders, they can also occur secondary to cerebral alterations like those existing in this boy. The introduction of modern neuroimaging techniques in patients with neuropsychiatric disorders (or the risk of developing them) can be very useful in the diagnosis and prognosis in the future. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

Risk assessment and comparative effectiveness of left ventricular assist device and medical management in ambulatory heart failure patients: design and rationale of the ROADMAP clinical trial.

Science.gov (United States)

Rogers, Joseph G; Boyle, Andrew J; O'Connell, John B; Horstmanshof, Douglas A; Haas, Donald C; Slaughter, Mark S; Park, Soon J; Farrar, David J; Starling, Randall C

2015-02-01

Mechanical circulatory support is now a proven therapy for the treatment of patients with advanced heart failure and cardiogenic shock. The role for this therapy in patients with less severe heart failure is unknown. The objective of this study is to examine the impact of mechanically assisted circulation using the HeartMate II left ventricular assist device in patients who meet current US Food and Drug Administration-defined criteria for treatment but are not yet receiving intravenous inotropic therapy. This is a prospective, nonrandomized clinical trial of 200 patients treated with either optimal medical management or a mechanical circulatory support device. This trial will be the first prospective clinical evaluation comparing outcomes of patients with advanced ambulatory heart failure treated with either ongoing medical therapy or a left ventricular assist device. It is anticipated to provide novel insights regarding relative outcomes with each treatment and an understanding of patient and provider acceptance of the ventricular assist device therapy. This trial will also provide information regarding the risk of events in "stable" patients with advanced heart failure and guidance for the optimal timing of left ventricular assist device therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

Repair of aorto-left ventricular tunnel arising from the left sinus of valsalva.

Science.gov (United States)

Nezafati, Mohammad Hassan; Maleki, Mahmood Hosseinzadeh; Javan, Hadi; Zirak, Nahid

2010-05-01

Aortico-left ventricular tunnel (ALVT) is a rare congenital cardiac defect that bypasses the aortic valve via a para-valvular connection from the left ventricle to the aorta. In most cases, the tunnel arises from the right aortic sinus. In this case report, we are presenting a case of ALVT, of which the aortic orifice arose from the left aortic sinus, requiring special attention to avoid the left coronary artery injury at the time of surgical repair.

Left bundle branch block as a risk factor for progression to heart failure

DEFF Research Database (Denmark)

Zannad, Faiez; Huvelle, Etienne; Dickstein, Kenneth

2006-01-01

The prevalence of conduction disturbances, particularly left bundle branch block (LBBB), is strongly correlated with age and with the presence of cardiovascular disease. LBBB has been reported to affect approximately 25% of the heart failure (HF) population and it is likely that the deleterious r...

Assembly of α-synuclein fibrils in nanoscale studied by peptide truncation and AFM

International Nuclear Information System (INIS)

Zhang Feng; Lin Xiaojing; Ji Lina; Du Haining; Tang Lin; He Jianhua; Hu Jun; Hu Hongyu

2008-01-01

α-Synuclein (α-Syn) fibrils are the major component of Lewy bodies that are closely associated with the pathogenesis of Parkinson's disease, but the mechanism for the fibril assembly remains poorly understood. Here we report using a combination of peptide truncation and atomic force microscopy (AFM) to elucidate the self-assembly and morphology of the α-Syn fibrils. The results show that protease K significantly slims the fibrils from the mean height of ∼6.6 to ∼4.7 nm, whereas chaotropic denaturant urea completely breaks down the fibrils into small particles. The in situ enzymatic digestion also results in thinning of the fibrils, giving rise to some nicks on the fibrils. Moreover, N- or C-terminally truncated α-Syn fragments assemble into thinner filaments with the heights depending on the peptide lengths. A nine-residue peptide corresponding to the homologous GAV-motif sequence can form very thin (∼2.2 nm) but long (>1 μm) filaments. Thus, the central sequence of α-Syn forms a fibrillar core by cross-β-structure that is flanked by two flexible termini, and the orientation of the fibril growth is perpendicular to the β-sheet structures

What's Left of the Left-Right Dimension? Why the Economic Policy Positions of Europeans Do Not Fit the Left-Right Dimension.

Science.gov (United States)

Otjes, Simon

2018-01-01

In political science the economic left-right dimension plays a central role. A growing body of evidence shows that the economic policy preferences of a large segment of citizens do not scale sufficiently. Using Mokken scale analysis, this study determines the causes of this phenomenon. Differences in the extent to which the economic policy preferences of citizens fit the left-right dimension can be explained in terms of the interaction between individual level and political system-level variables: citizens who spend more attention to politicians with views that conform to the left-right dimension, have views that conform to the left-right dimension. There is also a role for the legacy of communist dictatorship: citizens who were socialised in democratic countries have views that fit the left-right dimension better than those socialised during communism.

Anatomic relationship between left coronary artery and left atrium in patients undergoing atrial fibrillation ablation.

Science.gov (United States)

Anselmino, Matteo; Torri, Federica; Ferraris, Federico; Calò, Leonardo; Castagno, Davide; Gili, Sebastiano; Rovera, Chiara; Giustetto, Carla; Gaita, Fiorenzo

2017-07-01

Atrial fibrillation transcatheter ablation (TCA) is, within available atrial fibrillation rhythm control strategies, one of the most effective. To potentially improve ablation outcome in case of recurrent atrial fibrillation after a first procedure or in presence of structural myocardial disease, isolation of the pulmonary veins may be associated with extensive lesions within the left atrium. To avoid rare, but potentially life-threatening, complications, thorough knowledge and assessment of left atrium anatomy and its relation to structures in close proximity are, therefore, mandatory. Aim of the present study is to describe, by cardiac computed tomography, the anatomic relationship between aortic root, left coronary artery and left atrium in patients undergoing atrial fibrillation TCA. The cardiac computed tomography scan of 21 patients affected by atrial fibrillation was elaborated to segment left atrium, aortic root and left coronary artery from the surrounding structures and the following distances measured: left atrium and aortic root; left atrium roof and aortic root; left main coronary artery and left atrium; circumflex artery and left atrium appendage; and circumflex artery and mitral valve annulus. Above all, the median distance between left atrium and aortic root (1.9, 1.5-2.1 mm), and between circumflex artery and left atrium appendage ostium (3.0, 2.1-3.4 mm) were minimal (≤3 mm). None of measured distances significantly varied between patients presenting paroxysmal versus persistent atrial fibrillation. The anatomic relationship between left atrium and coronary arteries is extremely relevant when performing atrial fibrillation TCA by extensive lesions. Therefore, at least in the latter case, preablation imaging should be recommended to avoid rare, but potentially life-threatening, complications with the aim of an as well tolerated as possible procedure.

Limitation of myocardial infarct size and preservation of left ventricular function by early administration of APSAC in myocardial infarction.

Science.gov (United States)

Bassand, J P; Machecourt, J; Cassagnes, J; Lusson, J R; Borel, E; Schiele, F

1989-07-05

In cases of acute myocardial infarction (MI), it has been shown that preserving left ventricular function and limiting infarct size with early reperfusion of the occluded artery by means of a thrombolytic agent could eventually result in a reduced mortality rate. The aim of the APSIM study (anisoylated plasminogen streptokinase activator complex [APSAC] dans l'infarctus du Myocarde) was to demonstrate that early administration of APSAC in patients with recent acute MI could limit the infarct size and preserve left ventricular systolic function. In all, 231 patients with a first acute MI were randomly allocated to either APSAC (30 U over 5 minutes) or to conventional heparin therapy (5,000 IU in bolus injection) within 5 hours of the onset of symptoms. Of these patients, 112 received APSAC and 119 received heparin within a mean period of 188 +/- 62 minutes after the onset of symptoms. The patency rate of the infarct-related artery was 77% in the APSAC group and 36% in the heparin group (p less than 0.001). Left ventricular ejection fraction determined from contrast angiography was significantly higher in the APSAC than in the heparin group. This was true for the entire population (0.53 +/- 0.13 vs 0.47 +/- 0.13, p = 0.002) as well as for the subgroups of anterior and inferior wall infarctions (0.47 +/- 0.13 vs 0.4 +/- 0.16, p = 0.004 and 0.56 +/- 0.11 vs 0.51 +/- 0.09, p = 0.02). At 3 weeks, the difference remained significant for patients with anterior MI.(ABSTRACT TRUNCATED AT 250 WORDS)

Electro-optical study of nanoscale Al-Si-truncated conical photodetector with subwavelength aperture

Science.gov (United States)

Karelits, Matityahu; Mandelbaum, Yaakov; Chelly, Avraham; Karsenty, Avi

2017-10-01

A type of silicon photodiode has been designed and simulated to probe the optical near field and detect evanescent waves. These waves convey subwavelength resolution. This photodiode consists of a truncated conical shaped, silicon Schottky diode having a subwavelength aperture of 150 nm. Electrical and electro-optical simulations have been conducted. These results are promising toward the fabrication of a new generation of photodetector devices.

Mapping of the left-sided phrenic nerve course in patients undergoing left atrial catheter ablations.

Science.gov (United States)

Huemer, Martin; Wutzler, Alexander; Parwani, Abdul S; Attanasio, Philipp; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

2014-09-01

Catheter ablation of atrial fibrillation has been associated with left-sided phrenic nerve palsy. Knowledge of the individual left phrenic nerve course therefore is essential to prevent nerve injury. The aim of this study was to test the feasibility of an intraprocedural pace mapping and reconstruction of the left phrenic nerve course and to characterize which anatomical areas are affected. In patients undergoing left atrial catheter ablation, a three-dimensional map of the left atrial anatomical structures was created. The left-sided phrenic nerve course was determined by high-output pace mapping and reconstructed in the map. In this study, 40 patients with atrial fibrillation or atrial tachycardias were included. Left phrenic nerve capture was observed in 23 (57.5%) patients. Phrenic nerve was captured in 22 (55%) patients inside the left atrial appendage, in 22 (55%) in distal parts, in 21 (53%) in medial parts, and in two (5%) in ostial parts of the appendage. In three (7.5%) patients, capture was found in the distal coronary sinus and in one (2.5%) patient in the left atrium near the left atrial appendage ostium. Ablation target was changed due to direct spatial relationship to the phrenic nerve in three (7.5%) patients. No phrenic nerve palsy was observed. Left-sided phrenic nerve capture was found inside and around the left atrial appendage in the majority of patients and additionally in the distal coronary sinus. Phrenic nerve mapping and reconstruction can easily be performed and should be considered prior catheter ablations in potential affected areas. ©2014 Wiley Periodicals, Inc.

N-terminal pro brain natriuretic peptide in arterial hypertension--a marker for left ventricular dimensions and prognosis

DEFF Research Database (Denmark)

Hildebrandt, Per; Boesen, Mikael; Olsen, Michael

2004-01-01

In arterial hypertension risk factor evaluation, including LV mass measurements, and risk stratification using risk charts or programs, is generally recommended. In heart failure NT-proBNP has been shown to be a marker of LV dimensions and of prognosis. If the same diagnostic and prognostic value...... is present in arterial hypertension, risk factor evaluation would be easier. In 36 patients with arterial hypertension, electrocardiographic LV hypertrophy and preserved left ventricular function, NT-proBNP was eight-fold higher than in healthy subjects. The log NT-proBNP correlated with LV mass index (R=0.......47, P=0.0002) measured by magnetic resonance imaging. In other subjects with arterial hypertension a significant but weak correlation to diastolic properties has been demonstrated. As for prognosis, a recent study in patients with hypertension, electrocardiographic left ventricular hypertrophy...

Emergency Management of Malignant Acute Left-Sided Colonic Obstruction

Science.gov (United States)

Trompetas, Vasileios

2008-01-01

INTRODUCTION The management of acute left-sided colonic obstruction still remains a challenging problem despite significant progress. METHODS A literature search was undertaken using PubMed and the Cochrane Library regarding the options in emergency management of left-sided colonic obstruction focusing on outcomes such as mortality, morbidity, long-term prognosis and cost effectiveness. DISCUSSION Colonic stenting is the best option either for palliation or as a bridge to surgery. It reduces morbidity and mortality rate and the need for colostomy formation. Stenting is likely to be cost effective, but data are variable depending on the individual healthcare system. Nevertheless, surgical management remains relevant as colonic stenting has a small rate of failure, and it is not always available. There are various surgical options. One-stage primary resection and anastomosis is the preferred choice for low-risk patients. Intra-operative colonic irrigation has no proven benefit. Subtotal colectomy is useful in cases of proximal bowel damage or synchronous tumours. Hartmann's procedure should be reserved for high-risk patients. Simple colostomy has no role other than for use in very ill patients who are not fit for any other procedure. PMID:18430330

Cross-layer designed adaptive modulation algorithm with packet combining and truncated ARQ over MIMO Nakagami fading channels

KAUST Repository

Aniba, Ghassane

2011-04-01

This paper presents an optimal adaptive modulation (AM) algorithm designed using a cross-layer approach which combines truncated automatic repeat request (ARQ) protocol and packet combining. Transmissions are performed over multiple-input multiple-output (MIMO) Nakagami fading channels, and retransmitted packets are not necessarily modulated using the same modulation format as in the initial transmission. Compared to traditional approach, cross-layer design based on the coupling across the physical and link layers, has proven to yield better performance in wireless communications. However, there is a lack for the performance analysis and evaluation of such design when the ARQ protocol is used in conjunction with packet combining. Indeed, previous works addressed the link layer performance of AM with truncated ARQ but without packet combining. In addition, previously proposed AM algorithms are not optimal and can provide poor performance when packet combining is implemented. Herein, we first show that the packet loss rate (PLR) resulting from the combining of packets modulated with different constellations can be well approximated by an exponential function. This model is then used in the design of an optimal AM algorithm for systems employing packet combining, truncated ARQ and MIMO antenna configurations, considering transmission over Nakagami fading channels. Numerical results are provided for operation with or without packet combining, and show the enhanced performance and efficiency of the proposed algorithm in comparison with existing ones. © 2011 IEEE.

In-treatment reduced left atrial diameter during antihypertensive treatment is associated with reduced new-onset atrial fibrillation in hypertensive patients with left ventricular hypertrophy: The LIFE Study

DEFF Research Database (Denmark)

Wachtell, Kristian; Gerdts, Eva; Aurigemma, Gerard P

2010-01-01

It is unclear whether improvement of left atrial (LA) and ventricular (LV) structure results in reduction in new-onset atrial fibrillation (AF). The aim of the present study was to examine whether changes in-treatment LA diameter were related to changes in risk of new-onset AF....

Reducing C-terminal-truncated alpha-synuclein by immunotherapy attenuates neurodegeneration and propagation in Parkinson's disease-like models.

Science.gov (United States)

Games, Dora; Valera, Elvira; Spencer, Brian; Rockenstein, Edward; Mante, Michael; Adame, Anthony; Patrick, Christina; Ubhi, Kiren; Nuber, Silke; Sacayon, Patricia; Zago, Wagner; Seubert, Peter; Barbour, Robin; Schenk, Dale; Masliah, Eliezer

2014-07-09

Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are common neurodegenerative disorders of the aging population, characterized by progressive and abnormal accumulation of α-synuclein (α-syn). Recent studies have shown that C-terminus (CT) truncation and propagation of α-syn play a role in the pathogenesis of PD/DLB. Therefore, we explored the effect of passive immunization against the CT of α-syn in the mThy1-α-syn transgenic (tg) mouse model, which resembles the striato-nigral and motor deficits of PD. Mice were immunized with the new monoclonal antibodies 1H7, 5C1, or 5D12, all directed against the CT of α-syn. CT α-syn antibodies attenuated synaptic and axonal pathology, reduced the accumulation of CT-truncated α-syn (CT-α-syn) in axons, rescued the loss of tyrosine hydroxylase fibers in striatum, and improved motor and memory deficits. Among them, 1H7 and 5C1 were most effective at decreasing levels of CT-α-syn and higher-molecular-weight aggregates. Furthermore, in vitro studies showed that preincubation of recombinant α-syn with 1H7 and 5C1 prevented CT cleavage of α-syn. In a cell-based system, CT antibodies reduced cell-to-cell propagation of full-length α-syn, but not of the CT-α-syn that lacked the 118-126 aa recognition site needed for antibody binding. Furthermore, the results obtained after lentiviral expression of α-syn suggest that antibodies might be blocking the extracellular truncation of α-syn by calpain-1. Together, these results demonstrate that antibodies against the CT of α-syn reduce levels of CT-truncated fragments of the protein and its propagation, thus ameliorating PD-like pathology and improving behavioral and motor functions in a mouse model of this disease. Copyright © 2014 the authors 0270-6474/14/349441-14$15.00/0.

Risk of mental health and nutritional problems for left-behind children of international labor migrants.

Science.gov (United States)

Wickramage, Kolitha; Siriwardhana, Chesmal; Vidanapathirana, Puwalani; Weerawarna, Sulochana; Jayasekara, Buddhini; Pannala, Gayani; Adikari, Anushka; Jayaweera, Kaushalya; Peiris, Sharika; Siribaddana, Sisira; Sumathipala, Athula

2015-03-06

One-in-ten Sri Lankans are employed abroad as International Labor Migrants (ILM), mainly as domestic maids or low-skilled laborers. Little is known about the impact their migration has on the health status of the children they 'leave behind'. This national study explored associations between the health status of 'left-behind' children of ILM's with those from comparative non-migrant families. A cross-sectional study design with multi-stage random sampling was used to survey a total of 820 children matched for both age and sex. Socio-demographic and health status data were derived using standardized pre-validated instruments. Univariate and multivariate analyses were used to estimate the differences in mental health outcomes between children of migrant vs. non-migrant families. Two in every five left-behind children were shown to have mental disorders [95%CI: 37.4-49.2, p migration of labour, where remittances from ILM's remain as the single highest contributor to the economy. These findings may be relevant for other labour 'sending countries' in Asia relying on contractual labor migration for economic gain. Further studies are needed to assess longitudinal health impacts on the children left-behind.

Risk factors for profuse systemic-to-pulmonary artery collateral burden in hypoplastic left heart syndrome.

Science.gov (United States)

Prakash, Ashwin; Satiroglu, Elif; Porras, Diego; McElhinney, Doff B; Keane, John F; Lock, James E; Geva, Tal; King, Wilson; Powell, Andrew J

2013-08-01

Risk factors for developing systemic-to-pulmonary artery collaterals (SPCs) in hypoplastic left heart syndrome (HLHS) are unknown. We performed a retrospective case-control study to identify risk factors for developing a profuse SPC burden in HLHS. Angiograms of 439 patients with HLHS (performed <2 years of age) were reviewed using a previously published angiographic grading scale to identify cases (profuse SPC burden, n = 20) and controls (no or minimal SPC burden, n = 35). In univariate analyses, profuse SPC burden was associated with mitral atresia and aortic atresia subtype (MA/AA) (65% vs 14%, p <0.0001), use of a Sano shunt (70% vs 37%, p = 0.03), longer log-transformed durations of intensive care unit stay (p = 0.02), hospital stay (p = 0.002), pleural drainage (p = 0.008) after stage 1 palliation, lower oxygen saturation at discharge after stage 1 palliation (82 ± 4 vs 85 ± 4%, p = 0.03), and a history of severe shunt obstruction (37% vs 11%, p = 0.04). In a multivariate logistic regression model, profuse SPC burden was associated with MA/AA subtype (odds ratio 6.6), Sano shunt type (odds ratio 8.6), and log-transformed duration of hospital stay after stage 1 (odds ratio 7.9, model p <0.0001, area under the curve 0.88). Nonassociated parameters included fetal aortic valve dilation, severe cyanotic episodes, number of days with open sternum or number of additional exploratory thoracotomies after stage 1 palliation, pulmonary vein stenosis, and restrictive atrial septal defect. In conclusion, in the present case-control study of patients with HLHS, the development of a profuse SPC burden was associated with MA/AA subtype, Sano shunt type, and longer duration of hospital stay after stage 1 palliation. Copyright © 2013 Elsevier Inc. All rights reserved.

Multivariate density estimation using dimension reducing information and tail flattening transformations for truncated or censored data

DEFF Research Database (Denmark)

Buch-Kromann, Tine; Nielsen, Jens

2012-01-01

This paper introduces a multivariate density estimator for truncated and censored data with special emphasis on extreme values based on survival analysis. A local constant density estimator is considered. We extend this estimator by means of tail flattening transformation, dimension reducing prior...

Early Heparin Administration Reduces Risk for Left Atrial Thrombus Formation during Atrial Fibrillation Ablation Procedures

Directory of Open Access Journals (Sweden)

Stefan Asbach

2011-01-01

Full Text Available Objective. Despite the use of anticoagulation during left atrial (LA ablation procedures, ischemic cerebrovascular accidents (CVAs are recognized as a serious complication. Heparin is usually given after safe transseptal access has been obtained, resulting in a short unprotected dwell time of catheters within the LA, which may account for CVAs. We investigated the frequency of CVAs and LA thrombus formation as detected by intracardiac ultrasound (ICE depending on the timing of heparin administration. Methods and Results. Sixty LA ablation procedures with the use of ICE were performed in 55 patients. Patients were grouped by heparin administration after (Group I, =13 and before (Group II, =47 transseptal access. Group I patients were younger (56.6±13.7 versus 65.9±9.9 years, =.01; other clinical and echocardiographic characteristics did not differ between groups. Early thrombus formation was observed in 2 (15.4% of group I patients as compared to 0% of group II patients (=.04. One CVA (2.1% occurred in one group II patient without prior thrombus detection, and none occurred in group I patients (=ns. Conclusion. Early administration of heparin reduces the risk of early intracardiac thrombus formation during LA ablation procedures. This did not result in reduced rate of CVAs.

Transcatheter aortic valve implantation: emerging role in poor left ventricular function severe aortic stenosis?

Directory of Open Access Journals (Sweden)

K. M. John Chan

2014-01-01

Full Text Available Transcatheter aortic valve implantation (TAVI has become an established treatment option for high risk elderly patients with symptomatic severe aortic stenosis. Its role in less high risk patients is being evaluated in clinical trials. Patients with severely impaired left ventricular function may be another group who may benefit from this emerging percutaneous treatment option.

Reduced left ventricular dimension and function following early life stress: A thrifty phenotype hypothesis engendering risk for mood and anxiety disorders

Directory of Open Access Journals (Sweden)

Jeremy D. Coplan

2018-02-01

Full Text Available Background: Early life stress (ELS in macaques in the form of insecure maternal attachment putatively induces epigenetic adaptations resulting in a “thrifty phenotype” throughout the life cycle. For instance, ELS induces persistent increases in insulin resistance, hippocampal and corpus callosum atrophy and reduced “behavioral plasticity”, which, taken together, engenders an increased risk for mood and anxiety disorders in humans but also a putative sparing of calories. Herein, we test the hypothesis whether a thrifty phenotype induced by ELS is peripherally evident as hypotrophy of cardiac structure and function, raising the possibility that certain mood disorders may represent maladaptive physiological and central thrift adaptations. Methods: 14 adult bonnet macaques (6 males exposed to the maternal variable foraging demand (VFD model of ELS were compared to 20 non-VFD adult subjects (6 males. Left ventricle end-diastolic dimension (LVEDD, Left ventricle end-systolic dimension (LVESD and stroke volume (SV were calculated using echocardiography. Blood pressure and heart rate were measured only in females. Previously obtained neurobehavioral correlates available only in males were analyzed in the context of cardiac parameters. Results: Reduced LVESD (p < 0.05 was observed when controlled for age, sex, body weight and crown-rump length whereas ejection fraction (EF (p = 0.037 was greater in VFD-reared versus non-VFD subjects. Pulse pressure was lower in VFD versus non-VFD females (p < 0.05. Male timidity in response to a human intruder was associated with reduced LVEDD (p < 0.05. Conclusions: ELS is associated with both structural and functional reductions of left ventricular measures, potentially implying a body-wide thrifty phenotype. Parallel “thrift” adaptations may occur in key brain areas following ELS and may play an unexplored role in mood and anxiety disorder susceptibility.

The polyproline site in hinge 2 influences the functional capacity of truncated dystrophins.

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Glen B Banks

2010-05-01

Full Text Available Mutations in dystrophin can lead to Duchenne muscular dystrophy or the more mild form of the disease, Becker muscular dystrophy. The hinge 3 region in the rod domain of dystrophin is particularly prone to deletion mutations. In-frame deletions of hinge 3 are predicted to lead to BMD, however the severity of disease can vary considerably. Here we performed extensive structure-function analyses of truncated dystrophins with modified hinges and spectrin-like repeats in mdx mice. We found that the polyproline site in hinge 2 profoundly influences the functional capacity of a microdystrophin(DeltaR4-R23/DeltaCT with a large deletion in the hinge 3 region. Inclusion of polyproline in microdystrophin(DeltaR4-R23/DeltaCT led to small myofibers (12% smaller than wild-type, Achilles myotendinous disruption, ringed fibers, and aberrant neuromuscular junctions in the mdx gastrocnemius muscles. Replacing hinge 2 of microdystrophin(DeltaR4-R23/DeltaCT with hinge 3 significantly improved the functional capacity to prevent muscle degeneration, increase muscle fiber area, and maintain the junctions. We conclude that the rigid alpha-helical structure of the polyproline site significantly impairs the functional capacity of truncated dystrophins to maintain appropriate connections between the cytoskeleton and extracellular matrix.

Comment on the consistency of truncated nonlinear integral equation based theories of freezing

International Nuclear Information System (INIS)

Cerjan, C.; Bagchi, B.; Rice, S.A.

1985-01-01

We report the results of two studies of aspects of the consistency of truncated nonlinear integral equation based theories of freezing: (i) We show that the self-consistent solutions to these nonlinear equations are unfortunately sensitive to the level of truncation. For the hard sphere system, if the Wertheim--Thiele representation of the pair direct correlation function is used, the inclusion of part but not all of the triplet direct correlation function contribution, as has been common, worsens the predictions considerably. We also show that the convergence of the solutions found, with respect to number of reciprocal lattice vectors kept in the Fourier expansion of the crystal singlet density, is slow. These conclusions imply great sensitivity to the quality of the pair direct correlation function employed in the theory. (ii) We show the direct correlation function based and the pair correlation function based theories of freezing can be cast into a form which requires solution of isomorphous nonlinear integral equations. However, in the pair correlation function theory the usual neglect of the influence of inhomogeneity of the density distribution on the pair correlation function is shown to be inconsistent to the lowest order in the change of density on freezing, and to lead to erroneous predictions

Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

Directory of Open Access Journals (Sweden)

Jacques Luauté

2012-01-01

Full Text Available Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed.

Prognostic value of CT-derived left atrial and left ventricular measures in patients with acute chest pain

Energy Technology Data Exchange (ETDEWEB)

Takx, Richard A.P. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, University Medical Center Utrecht (Netherlands); Vliegenthart, Rozemarijn [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); University of Groningen/University Medical Center Groningen, Center for Medical Imaging − North East Netherlands, Department of Radiology, Groningen (Netherlands); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Nance, John W. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Bamberg, Fabian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, Eberhard-Karls University Tuebingen, Tuebingen (Germany); Abro, Joseph A. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Carr, Christine M. [Division of Emergency Medicine, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Litwin, Sheldon E. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); and others

2017-01-15

Highlights: • LV mass and LA diameter are independent prognostic factor for composite MACE. • LV mass and LA diameter were not significant prognostic factors for MACE in African Americans. • Assessment of LV mass by CT may have a role in the management of patients. - Abstract: Purpose: To determine which left atrial (LA) and left ventricular (LV) parameters are associated with future major adverse cardiac event (MACE) and whether these measurements have independent prognostic value beyond risk factors and computed tomography (CT)-derived coronary artery disease measures. Materials and methods: This retrospective analysis was performed under an IRB waiver and in HIPAA compliance. Subjects underwent coronary CT angiography (CCTA) using a dual-source CT system for acute chest pain evaluation. LV mass, LV ejection fraction (EF), LV end-systolic volume (ESV) and LV end-diastolic volume (EDV), LA ESV and LA diameter, septal wall thickness and cardiac chamber diameters were measured. MACE was defined as cardiac death, non-fatal myocardial infarction, unstable angina, or late revascularization. The association between cardiac CT measures and the occurrence of MACE was quantified using Cox proportional hazard analysis. Results: 225 subjects (age, 56.2 ± 11.2; 140 males) were analyzed, of whom 42 (18.7%) experienced a MACE during a median follow-up of 13 months. LA diameter (HR:1.07, 95%CI:1.01–1.13 per mm) and LV mass (HR:1.05, 95%CI:1.00–1.10 per g) remained significant prognostic factor of MACE after controlling for Framingham risk score. LA diameter and LV mass were also found to have prognostic value independent of each other. The other morphologic and functional cardiac measures were no significant prognostic factors for MACE. Conclusion: CT-derived LA diameter and LV mass are associated with future MACE in patients undergoing evaluation for chest pain, and portend independent prognostic value beyond traditional risk factors, coronary calcium score, and

Long-term survival of quiescent left atrial myxoma in an elderly patient.

Science.gov (United States)

Kay, Jay F L; Chow, Wing Hing

2002-01-01

Left atrial myxoma, if left untreated, is inexorably progressive and usually fatal. The classical management of this disease is prompt surgical removal. However, there may be exceptions to this traditional dogma. The authors report an 85-year-old man who presented with features of chronic obstructive airway disease and congestive heart failure 15 years previously. Auscultation of the heart showed a pansystolic murmur. Two-dimensional echocardiography revealed a nonobstructive, calcified, and well circumscribed mass in the left atrium, with a pedicle attached to the interatrial septum. Because the patient refused high-risk cardiac surgery related to his comorbidity, he was managed medically with a bronchodilator, diuretics, and digoxin. There have been no features of embolism or intracardiac obstruction, and serial echocardiography demonstrates no disease progression over this long period of time. This case illustrates that calcified left atrial myxoma may exhibit a quiescent phase. Tumor calcification, slow growth potential, and the absence of intracardiac obstruction may correlate with a better outcome in the elderly patient. (c)2002 CVRR, Inc.

On the Analytical and Numerical Properties of the Truncated Laplace Transform

Science.gov (United States)

2014-05-01

classical study of the truncated Fourier trans- form. The resulting algorithms are applicable to all environments likely to be encountered in applications...other words, (((La,b)∗ ◦ La,b) (un)) (t) = ∫ b a 1 t+ s un(s)ds = α 2 nun (t). (2.69) Observation 2.22. Similarly, La,b ◦ (La,b)∗ of a function g ∈ L2(0...3.20)) are even and odd functions in the regular sense: Un(s) = (Cγ(un)) (s) = (−1) nUn (−s). (3.25) In particular, at the point s = 0, we have: U2j+1(0

Analysis and design of optimized truncated scarfed nozzles subject to external flow effects

Science.gov (United States)

Shyne, Rickey J.; Keith, Theo G., Jr.

1990-01-01

Rao's method for computing optimum thrust nozzles is modified to study the effects of external flow on the performance of a class of exhaust nozzles. Members of this class are termed scarfed nozzles. These are two-dimensional, nonsymmetric nozzles with a flat lower wall. The lower wall (the cowl) is truncated in order to save weight. Results from a parametric investigation are presented to show the effects of the external flowfield on performance.

Truncating PREX2 mutations activate its GEF activity and alter gene expression regulation in NRAS-mutant melanoma

KAUST Repository

Lissanu Deribe, Yonathan

2016-03-01

PREX2 (phosphatidylinositol-3,4,5-triphosphate-dependent Rac-exchange factor 2) is a PTEN (phosphatase and tensin homolog deleted on chromosome 10) binding protein that is significantly mutated in cutaneous melanoma and pancreatic ductal adenocarcinoma. Here, genetic and biochemical analyses were conducted to elucidate the nature and mechanistic basis of PREX2 mutation in melanoma development. By generating an inducible transgenic mouse model we showed an oncogenic role for a truncating PREX2 mutation (PREX2E824*) in vivo in the context of mutant NRAS. Using integrative cross-species gene expression analysis, we identified deregulated cell cycle and cytoskeleton organization as significantly perturbed biological pathways in PREX2 mutant tumors. Mechanistically, truncation of PREX2 activated its Rac1 guanine nucleotide exchange factor activity, abolished binding to PTEN and activated the PI3K (phosphatidyl inositol 3 kinase)/Akt signaling pathway. We further showed that PREX2 truncating mutations or PTEN deletion induces down-regulation of the tumor suppressor and cell cycle regulator CDKN1C (also known as p57KIP2). This down-regulation occurs, at least partially, through DNA hypomethylation of a differentially methylated region in chromosome 11 that is a known regulatory region for expression of the CDKN1C gene. Together, these findings identify PREX2 as a mediator of NRAS-mutant melanoma development that acts through the PI3K/PTEN/Akt pathway to regulate gene expression of a cell cycle regulator.

Truncating PREX2 mutations activate its GEF activity and alter gene expression regulation in NRAS-mutant melanoma.

Science.gov (United States)

Lissanu Deribe, Yonathan; Shi, Yanxia; Rai, Kunal; Nezi, Luigi; Amin, Samir B; Wu, Chia-Chin; Akdemir, Kadir C; Mahdavi, Mozhdeh; Peng, Qian; Chang, Qing Edward; Hornigold, Kirsti; Arold, Stefan T; Welch, Heidi C E; Garraway, Levi A; Chin, Lynda

2016-03-01

PREX2 (phosphatidylinositol-3,4,5-triphosphate-dependent Rac-exchange factor 2) is a PTEN (phosphatase and tensin homolog deleted on chromosome 10) binding protein that is significantly mutated in cutaneous melanoma and pancreatic ductal adenocarcinoma. Here, genetic and biochemical analyses were conducted to elucidate the nature and mechanistic basis of PREX2 mutation in melanoma development. By generating an inducible transgenic mouse model we showed an oncogenic role for a truncating PREX2 mutation (PREX2(E824)*) in vivo in the context of mutant NRAS. Using integrative cross-species gene expression analysis, we identified deregulated cell cycle and cytoskeleton organization as significantly perturbed biological pathways in PREX2 mutant tumors. Mechanistically, truncation of PREX2 activated its Rac1 guanine nucleotide exchange factor activity, abolished binding to PTEN and activated the PI3K (phosphatidyl inositol 3 kinase)/Akt signaling pathway. We further showed that PREX2 truncating mutations or PTEN deletion induces down-regulation of the tumor suppressor and cell cycle regulator CDKN1C (also known as p57(KIP2)). This down-regulation occurs, at least partially, through DNA hypomethylation of a differentially methylated region in chromosome 11 that is a known regulatory region for expression of the CDKN1C gene. Together, these findings identify PREX2 as a mediator of NRAS-mutant melanoma development that acts through the PI3K/PTEN/Akt pathway to regulate gene expression of a cell cycle regulator.

Truncating PREX2 mutations activate its GEF activity and alter gene expression regulation in NRAS-mutant melanoma

KAUST Repository

Lissanu Deribe, Yonathan; Shi, Yanxia; Rai, Kunal; Nezi, Luigi; Amin, Samir B.; Wu, Chia-Chin; Akdemir, Kadir C.; Mahdavi, Mozhdeh; Peng, Qian; Chang, Qing Edward; Hornigold, Kirsti; Arold, Stefan T.; Welch, Heidi C. E.; Garraway, Levi A.; Chin, Lynda

2016-01-01

PREX2 (phosphatidylinositol-3,4,5-triphosphate-dependent Rac-exchange factor 2) is a PTEN (phosphatase and tensin homolog deleted on chromosome 10) binding protein that is significantly mutated in cutaneous melanoma and pancreatic ductal adenocarcinoma. Here, genetic and biochemical analyses were conducted to elucidate the nature and mechanistic basis of PREX2 mutation in melanoma development. By generating an inducible transgenic mouse model we showed an oncogenic role for a truncating PREX2 mutation (PREX2E824*) in vivo in the context of mutant NRAS. Using integrative cross-species gene expression analysis, we identified deregulated cell cycle and cytoskeleton organization as significantly perturbed biological pathways in PREX2 mutant tumors. Mechanistically, truncation of PREX2 activated its Rac1 guanine nucleotide exchange factor activity, abolished binding to PTEN and activated the PI3K (phosphatidyl inositol 3 kinase)/Akt signaling pathway. We further showed that PREX2 truncating mutations or PTEN deletion induces down-regulation of the tumor suppressor and cell cycle regulator CDKN1C (also known as p57KIP2). This down-regulation occurs, at least partially, through DNA hypomethylation of a differentially methylated region in chromosome 11 that is a known regulatory region for expression of the CDKN1C gene. Together, these findings identify PREX2 as a mediator of NRAS-mutant melanoma development that acts through the PI3K/PTEN/Akt pathway to regulate gene expression of a cell cycle regulator.

Cross-layer designed adaptive modulation algorithm with packet combining and truncated ARQ over MIMO Nakagami fading channels

KAUST Repository

Aniba, Ghassane; Aissa, Sonia

2011-01-01

works addressed the link layer performance of AM with truncated ARQ but without packet combining. In addition, previously proposed AM algorithms are not optimal and can provide poor performance when packet combining is implemented. Herein, we first show

Ptychographic x-ray imaging of surfaces on crystal truncation rod

Energy Technology Data Exchange (ETDEWEB)

Zhu, Chenhui; Barbour, Andi; Liu, Yaohua; You, Hoydoo, E-mail: hyou@anl.gov [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Harder, Ross; Xu, Ruqing [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Diaz, Ana; Menzel, Andreas [Paul Scherrer Institut, Villigen PSI 5232 (Switzerland); Komanicky, Vladimir [Faculty of Sciences, Safarik University, Kosice 04154 (Slovakia); Huang, Xiaojing [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973 (United States); Pierce, Michael S. [School of Physics and Astronomy, Rochester Institute of Technology, Rochester, New York 14623 (United States)

2015-03-09

Ptychography is a high-resolution imaging technique, which does not require lenses for image magnification and which provides phase contrast with high sensitivity. Here, we propose to use x-ray ptychography for the imaging of surface structure in crystalline samples. We show that ptychography can be used to image atomic step structures using coherent diffraction patterns recorded along the crystal truncation rod of a crystal surface. In a proof-of-concept experiment on a Pt (111) sample, we present ptychographic reconstructions showing features consistent with surface steps. Due to the penetration power of x-rays, this method could find interesting applications for the study of surface structures under buried interfaces or in harsh environments.

Ptychographic x-ray imaging of surfaces on crystal truncation rod

International Nuclear Information System (INIS)

Zhu, Chenhui; Barbour, Andi; Liu, Yaohua; You, Hoydoo; Harder, Ross; Xu, Ruqing; Diaz, Ana; Menzel, Andreas; Komanicky, Vladimir; Huang, Xiaojing; Pierce, Michael S.

2015-01-01

Ptychography is a high-resolution imaging technique, which does not require lenses for image magnification and which provides phase contrast with high sensitivity. Here, we propose to use x-ray ptychography for the imaging of surface structure in crystalline samples. We show that ptychography can be used to image atomic step structures using coherent diffraction patterns recorded along the crystal truncation rod of a crystal surface. In a proof-of-concept experiment on a Pt (111) sample, we present ptychographic reconstructions showing features consistent with surface steps. Due to the penetration power of x-rays, this method could find interesting applications for the study of surface structures under buried interfaces or in harsh environments

Non-perturbative Calculation of the Scalar Yukawa Theory in Four-Body Truncation

International Nuclear Information System (INIS)

Li, Yang; Maris, P.; Vary, J. P.; Karmanov, V. A.

2015-01-01

The quenched scalar Yukawa theory is solved in the light-front Tamm–Dancoff approach including up to four constituents (one scalar nucleon, three scalar pions). The Fock sector dependent renormalization is implemented. By studying the Fock sector norms, we find that the lowest two Fock sectors dominate the state even in the large-coupling region. The one-body sector shows convergence with respect to the Fock sector truncation. However, the four-body norm exceeds the three-body norm at the coupling α≈1.7 . (author)

Microvolt T-wave alternans and autonomic nervous system parameters can be helpful in the identification of low-arrhythmic risk patients with ischemic left ventricular systolic dysfunction.

Science.gov (United States)

Daniłowicz-Szymanowicz, Ludmiła; Kaufmann, Damian; Rozwadowska, Katarzyna; Kempa, Maciej; Lewicka, Ewa; Raczak, Grzegorz

2018-01-01

The role of implantable cardioverter-defibrillator (ICD) placement in the primary prevention of sudden cardiac death (SCD) in all consecutive patients with left ventricular ejection fraction (LVEF) ≤ 35% is still a matter of hot debate due to the fact that the population of these patients is highly heterogeneous in terms of the SCD risk. Nevertheless, reduced LVEF is still the only established criterion during qualification of patients for ICD implantation in the primary prevention of SCD, therefore identification of persons with particularly high risk among patients with LVEF ≤35% is currently of lesser importance. More important seems to be the selection of individuals with relatively low risk of SCD in whom ICD implantation can be safely postponed. The aim of the study was to determine whether well-known, non-invasive parameters, such as microvolt T-wave alternans (MTWA), baroreflex sensitivity (BRS) and short-term heart rate variability (HRV), can be helpful in the identification of low-arrhythmic risk patients with ischemic left ventricular systolic dysfunction. In 141 patients with coronary artery disease and LVEF ≤ 35%, MTWA testing, as well as BRS and short-term HRV parameters, were analysed. During 34 ± 13 months of follow-up 37 patients had arrhythmic episode (EVENT): SCD, non-fatal sustained ventricular arrhythmia (ventricular tachycardia [VT] or ventricular fibrillation [VF]), or adequate high-voltage ICD intervention (shock) due to a rapid ventricular arrhythmia ≥200/min. LVEF, non-negative MTWA (MTWA_non-neg), BRS and low frequency power in normalized units (LFnu) turned out to be associated with the incidence of EVENT in univariate Cox analysis. The cut-off values for BRS and LFnu that most accurately distinguished between patients with and without EVENT were 3 ms/mmHg and 23, respectively. The only variable that provided 100% negative predictive value (NPV) for EVENT was negative MTWA result (MTWA_neg), but solely for initial 12 months of

TMS over the Left Angular Gyrus Impairs the Ability to Discriminate Left from Right

Science.gov (United States)

Hirnstein, Marco; Bayer, Ulrike; Ellison, Amanda; Hausmann, Markus

2011-01-01

The underlying cognitive and neural mechanisms of the ability to discriminate left from right are hardly explored. Clinical studies from patients with impairments of left-right discrimination (LRD) and neuroimaging data suggest that the left angular gyrus is particularly involved in LRD. Moreover, it is argued that the often reported sex…

Performance Analysis of Thermoelectric Modules Consisting of Square Truncated Pyramid Elements Under Constant Heat Flux

Science.gov (United States)

Oki, Sae; Natsui, Shungo; Suzuki, Ryosuke O.

2018-06-01

System design of a thermoelectric (TE) power generation module is pursued in order to improve the TE performance. Square truncated pyramid shaped P-N pairs of TE elements are connected electronically in series in the open space between two flat insulator boards. The performance of the TE module consisting of 2-paired elements is numerically simulated using commercial software and original TE programs. Assuming that the heat radiating into the hot surface is regulated, i.e., the amount of heat from the hot surface to the cold one is steadily constant, as it happens for solar radiation heating, the performance is significantly improved by changing the shape and the alignment pattern of the elements. When the angle θ between the edge and the base is smaller than 72°, and when the cold surface is kept at a constant temperature, two patterns in particular, amongst the 17 studied, show the largest TE power and efficiency. In comparison to other geometries, the smarter square truncated pyramid shape can provide higher performance using a large cold bath and constant heat transfer by heat radiation.

Impact of improved attenuation correction featuring a bone atlas and truncation correction on PET quantification in whole-body PET/MR.

Science.gov (United States)

Oehmigen, Mark; Lindemann, Maike E; Gratz, Marcel; Kirchner, Julian; Ruhlmann, Verena; Umutlu, Lale; Blumhagen, Jan Ole; Fenchel, Matthias; Quick, Harald H

2018-04-01

Recent studies have shown an excellent correlation between PET/MR and PET/CT hybrid imaging in detecting lesions. However, a systematic underestimation of PET quantification in PET/MR has been observed. This is attributable to two methodological challenges of MR-based attenuation correction (AC): (1) lack of bone information, and (2) truncation of the MR-based AC maps (μmaps) along the patient arms. The aim of this study was to evaluate the impact of improved AC featuring a bone atlas and truncation correction on PET quantification in whole-body PET/MR. The MR-based Dixon method provides four-compartment μmaps (background air, lungs, fat, soft tissue) which served as a reference for PET/MR AC in this study. A model-based bone atlas provided bone tissue as a fifth compartment, while the HUGE method provided truncation correction. The study population comprised 51 patients with oncological diseases, all of whom underwent a whole-body PET/MR examination. Each whole-body PET dataset was reconstructed four times using standard four-compartment μmaps, five-compartment μmaps, four-compartment μmaps + HUGE, and five-compartment μmaps + HUGE. The SUV max for each lesion was measured to assess the impact of each μmap on PET quantification. All four μmaps in each patient provided robust results for reconstruction of the AC PET data. Overall, SUV max was quantified in 99 tumours and lesions. Compared to the reference four-compartment μmap, the mean SUV max of all 99 lesions increased by 1.4 ± 2.5% when bone was added, by 2.1 ± 3.5% when HUGE was added, and by 4.4 ± 5.7% when bone + HUGE was added. Larger quantification bias of up to 35% was found for single lesions when bone and truncation correction were added to the μmaps, depending on their individual location in the body. The novel AC method, featuring a bone model and truncation correction, improved PET quantification in whole-body PET/MR imaging. Short reconstruction times, straightforward

Impact of improved attenuation correction featuring a bone atlas and truncation correction on PET quantification in whole-body PET/MR

Energy Technology Data Exchange (ETDEWEB)

Oehmigen, Mark; Lindemann, Maike E. [University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany); Gratz, Marcel; Quick, Harald H. [University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany); University Duisburg-Essen, Erwin L. Hahn Institute for MR Imaging, Essen (Germany); Kirchner, Julian [University Dusseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Dusseldorf (Germany); Ruhlmann, Verena [University Hospital Essen, Department of Nuclear Medicine, Essen (Germany); Umutlu, Lale [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Blumhagen, Jan Ole; Fenchel, Matthias [Siemens Healthcare GmbH, Erlangen (Germany)

2018-04-15

Recent studies have shown an excellent correlation between PET/MR and PET/CT hybrid imaging in detecting lesions. However, a systematic underestimation of PET quantification in PET/MR has been observed. This is attributable to two methodological challenges of MR-based attenuation correction (AC): (1) lack of bone information, and (2) truncation of the MR-based AC maps (μmaps) along the patient arms. The aim of this study was to evaluate the impact of improved AC featuring a bone atlas and truncation correction on PET quantification in whole-body PET/MR. The MR-based Dixon method provides four-compartment μmaps (background air, lungs, fat, soft tissue) which served as a reference for PET/MR AC in this study. A model-based bone atlas provided bone tissue as a fifth compartment, while the HUGE method provided truncation correction. The study population comprised 51 patients with oncological diseases, all of whom underwent a whole-body PET/MR examination. Each whole-body PET dataset was reconstructed four times using standard four-compartment μmaps, five-compartment μmaps, four-compartment μmaps + HUGE, and five-compartment μmaps + HUGE. The SUV{sub max} for each lesion was measured to assess the impact of each μmap on PET quantification. All four μmaps in each patient provided robust results for reconstruction of the AC PET data. Overall, SUV{sub max} was quantified in 99 tumours and lesions. Compared to the reference four-compartment μmap, the mean SUV{sub max} of all 99 lesions increased by 1.4 ± 2.5% when bone was added, by 2.1 ± 3.5% when HUGE was added, and by 4.4 ± 5.7% when bone + HUGE was added. Larger quantification bias of up to 35% was found for single lesions when bone and truncation correction were added to the μmaps, depending on their individual location in the body. The novel AC method, featuring a bone model and truncation correction, improved PET quantification in whole-body PET/MR imaging. Short reconstruction times, straightforward

Prediction of the moments in advection-diffusion lattice Boltzmann method. I. Truncation dispersion, skewness, and kurtosis

Science.gov (United States)

Ginzburg, Irina

2017-01-01

The effect of the heterogeneity in the soil structure or the nonuniformity of the velocity field on the modeled resident time distribution (RTD) and breakthrough curves is quantified by their moments. While the first moment provides the effective velocity, the second moment is related to the longitudinal dispersion coefficient (kT) in the developed Taylor regime; the third and fourth moments are characterized by their normalized values skewness (Sk) and kurtosis (Ku), respectively. The purpose of this investigation is to examine the role of the truncation corrections of the numerical scheme in kT, Sk, and Ku because of their interference with the second moment, in the form of the numerical dispersion, and in the higher-order moments, by their definition. Our symbolic procedure is based on the recently proposed extended method of moments (EMM). Originally, the EMM restores any-order physical moments of the RTD or averaged distributions assuming that the solute concentration obeys the advection-diffusion equation in multidimensional steady-state velocity field, in streamwise-periodic heterogeneous structure. In our work, the EMM is generalized to the fourth-order-accurate apparent mass-conservation equation in two- and three-dimensional duct flows. The method looks for the solution of the transport equation as the product of a long harmonic wave and a spatially periodic oscillating component; the moments of the given numerical scheme are derived from a chain of the steady-state fourth-order equations at a single cell. This mathematical technique is exemplified for the truncation terms of the two-relaxation-time lattice Boltzmann scheme, using plug and parabolic flow in straight channel and cylindrical capillary with the d2Q9 and d3Q15 discrete velocity sets as simple but illustrative examples. The derived symbolic dependencies can be readily extended for advection by another, Newtonian or non-Newtonian, flow profile in any-shape open-tabular conduits. It is

Truncating variants in the majority of the cytoplasmic domain of PCDH15 are unlikely to cause Usher syndrome 1F.

Science.gov (United States)

Perreault-Micale, Cynthia; Frieden, Alexander; Kennedy, Caleb J; Neitzel, Dana; Sullivan, Jessica; Faulkner, Nicole; Hallam, Stephanie; Greger, Valerie

2014-11-01

Loss of function variants in the PCDH15 gene can cause Usher syndrome type 1F, an autosomal recessive disease associated with profound congenital hearing loss, vestibular dysfunction, and retinitis pigmentosa. The Ashkenazi Jewish population has an increased incidence of Usher syndrome type 1F (founder variant p.Arg245X accounts for 75% of alleles), yet the variant spectrum in a panethnic population remains undetermined. We sequenced the coding region and intron-exon borders of PCDH15 using next-generation DNA sequencing technology in approximately 14,000 patients from fertility clinics. More than 600 unique PCDH15 variants (single nucleotide changes and small indels) were identified, including previously described pathogenic variants p.Arg3X, p.Arg245X (five patients), p.Arg643X, p.Arg929X, and p.Arg1106X. Novel truncating variants were also found, including one in the N-terminal extracellular domain (p.Leu877X), but all other novel truncating variants clustered in the exon 33 encoded C-terminal cytoplasmic domain (52 patients, 14 variants). One variant was observed predominantly in African Americans (carrier frequency of 2.3%). The high incidence of truncating exon 33 variants indicates that they are unlikely to cause Usher syndrome type 1F even though many remove a large portion of the gene. They may be tolerated because PCDH15 has several alternate cytoplasmic domain exons and differentially spliced isoforms may function redundantly. Effects of some PCDH15 truncating variants were addressed by deep sequencing of a panethnic population. Copyright © 2014 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Novel and recurrent non-truncating mutations of the MITF basic domain: genotypic and phenotypic variations in Waardenburg and Tietz syndromes

Science.gov (United States)

Léger, Sandy; Balguerie, Xavier; Goldenberg, Alice; Drouin-Garraud, Valérie; Cabot, Annick; Amstutz-Montadert, Isabelle; Young, Paul; Joly, Pascal; Bodereau, Virginie; Holder-Espinasse, Muriel; Jamieson, Robyn V; Krause, Amanda; Chen, Hongsheng; Baumann, Clarisse; Nunes, Luis; Dollfus, Hélène; Goossens, Michel; Pingault, Véronique

2012-01-01

The microphthalmia-associated transcription factor (MITF) is a basic helix-loop-helix leucine zipper transcription factor, which regulates melanocyte development and the biosynthetic melanin pathway. A notable relationship has been described between non-truncating mutations of its basic domain and Tietz syndrome, which is characterized by albinoid-like hypopigmentation of the skin and hair, rather than the patchy depigmentation seen in Waardenburg syndrome, and severe hearing loss. Twelve patients with new or recurrent non-truncating mutations of the MITF basic domain from six families were enrolled in this study. We observed a wide range of phenotypes and some unexpected features. All the patients had blue irides and pigmentation abnormalities that ranged from diffuse hypopigmentation to Waardenburg-like patches. In addition, they showed congenital complete hearing loss, diffuse hypopigmentation of the skin, freckling and ocular abnormalities, more frequently than patients with MITF mutations outside the basic domain. In conclusion, the non-truncating mutations of the basic domain do not always lead to Tietz syndrome but rather to a large range of phenotypes. Sun-exposed freckles are interestingly observed more frequently in Asian populations. This variability argues for the possible interaction with modifier loci. PMID:22258527

Management of severe ischemic cardiomyopathy: left ventricular assist device as destination therapy versus conventional bypass and mitral valve surgery.

Science.gov (United States)

Maltais, Simon; Tchantchaleishvili, Vahtang; Schaff, Hartzell V; Daly, Richard C; Suri, Rakesh M; Dearani, Joseph A; Topilsky, Yan; Stulak, John M; Joyce, Lyle D; Park, Soon J

2014-04-01

Patients with severe ischemic cardiomyopathy (left ventricular ejection fraction assist device as destination therapy is reserved for patients who are too high risk for conventional surgery. We evaluated our outcomes with conventional surgery within this population and the comparative effectiveness of these 2 therapies. We identified patients who underwent conventional surgery or left ventricular assist device as destination therapy for severe ischemic cardiomyopathy (left ventricular ejection fraction assist device as destination therapy. We compared baseline patient characteristics and outcomes in terms of end-organ function and survival. A total of 88 patients were identified; 55 patients underwent conventional surgery (63%), and 33 patients (37%) received a left ventricular assist device as destination therapy. Patients who received left ventricular assist device as destination therapy had the increased prevalence of renal failure, inotrope dependency, and intra-aortic balloon support. Patients undergoing conventional surgery required longer ventilatory support, and patients receiving a left ventricular assist device required more reoperation for bleeding. Mortality rates were similar between the 2 groups at 30 days (7% in the conventional surgery group vs 3% in the left ventricular assist device as destination therapy group, P = .65) and at 1 year (22% in the conventional surgery group vs 15% in the left ventricular assist device as destination therapy group, P = .58). There was a trend toward improved survival in patients receiving a left ventricular assist device compared with the propensity-matched groups at 1 year (94% vs 71%, P = .171). The operative mortality and early survival after conventional surgery seem to be acceptable. For inoperable or prohibitive-risk patients, left ventricular assist device as destination therapy can be offered with similar outcomes. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby

Uniform physical theory of diffraction equivalent edge currents for truncated wedge strips

DEFF Research Database (Denmark)

Johansen, Peter Meincke

1996-01-01

New uniform closed-form expressions for physical theory of diffraction equivalent edge currents are derived for truncated incremental wedge strips. In contrast to previously reported expressions, the new expressions are well behaved for all directions of incidence and observation and take a finite...... value for zero strip length. This means that the expressions are well suited for implementation in general computer codes. The new expressions are expressed as the difference between two terms. The first term is obtained by integrating the exact fringe wave current on a wedge along an untruncated...

Computation of Lie transformations from a power series: Bounds and optimum truncation

International Nuclear Information System (INIS)

Gjaja, I.

1996-01-01

The problem considered is the computation of an infinite product (composition) of Lie transformations generated by homogeneous polynomials of increasing order from a given asymptotic power series. Bounds are computed for the infinitesimal form of the Lie transformations and for the domain of analyticity of the first n of them. Even when the power series is convergent, the estimates exhibit a factorial-type growth, and thus do not guarantee convergence of the product. The optimum truncation is determined by minimizing the remainder after the first n Lie transformations have been applied

Dyscalculia, Dysgraphia, and Left-Right Confusion from a Left Posterior Peri-Insular Infarct

Directory of Open Access Journals (Sweden)

S. Bhattacharyya

2014-01-01

Full Text Available The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

Dyscalculia, dysgraphia, and left-right confusion from a left posterior peri-insular infarct.

Science.gov (United States)

Bhattacharyya, S; Cai, X; Klein, J P

2014-01-01

The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

Apraxia in left-handers.

Science.gov (United States)

Goldenberg, Georg

2013-08-01

In typical right-handed patients both apraxia and aphasia are caused by damage to the left hemisphere, which also controls the dominant right hand. In left-handed subjects the lateralities of language and of control of the dominant hand can dissociate. This permits disentangling the association of apraxia with aphasia from that with handedness. Pantomime of tool use, actual tool use and imitation of meaningless hand and finger postures were examined in 50 consecutive left-handed subjects with unilateral hemisphere lesions. There were three aphasic patients with pervasive apraxia caused by left-sided lesions. As the dominant hand is controlled by the right hemisphere, they constitute dissociations of apraxia from handedness. Conversely there were also three patients with pervasive apraxia caused by right brain lesions without aphasia. They constitute dissociations of apraxia from aphasia. Across the whole group of patients dissociations from handedness and from aphasia were observed for all manifestations of apraxia, but their frequency depended on the type of apraxia. Defective pantomime and defective tool use occurred rarely without aphasia, whereas defective imitation of hand, but not finger, postures was more frequent after right than left brain damage. The higher incidence of defective imitation of hand postures in right brain damage was mainly due to patients who had also hemi-neglect. This interaction alerts to the possibility that the association of right hemisphere damage with apraxia has to do with spatial aptitudes of the right hemisphere rather than with its control of the dominant left hand. Comparison with data from right-handed patients showed no differences between the severity of apraxia for imitation of hand or finger postures, but impairment on pantomime of tool use was milder in apraxic left-handers than in apraxic right-handers. This alleviation of the severity of apraxia corresponded with a similar alleviation of the severity of aphasia as

Expression of a truncated receptor protein tyrosine phosphatase kappa in the brain of an adult transgenic mouse

DEFF Research Database (Denmark)

Shen, P; Canoll, P D; Sap, J

1999-01-01

processes such as axonal growth and target recognition, as has been demonstrated for certain Drosophila RPTPs. The brain distribution of RPTP-kappa-expressing cells has not been determined, however. In a gene-trap mouse model with a beta-gal+neo (beta-geo) insertion in the endogenous RPTP-kappa gene......-6596]. Nevertheless, since the transgene's expression is driven by the endogenous RPTP-kappa promoter, distribution of the truncated RPTP-kappa/beta-geo fusion protein should reflect the regional and cellular expression of wild-type RPTP-kappa, and thus may identify sites where RPTP-kappa is important. Towards...... that goal, we have used this mouse model to map the distribution of the truncated RPTP-kappa/beta-geo fusion protein in the adult mouse brain using beta-galactosidase as a marker enzyme. Visualization of the beta-galactosidase activity revealed a non-random pattern of expression, and identified cells...

A Left-Sided Prevalence of Lentigo Maligna: A UK Based Observational Study and Review of the Evidence

Directory of Open Access Journals (Sweden)

Mark Gorman

2015-01-01

Full Text Available Skin cancer has been shown to present asymmetrically, prevalent on the left side of the body, more so in subtypes of cutaneous melanoma such as lentigo maligna. Biases have been linked to cumulative UV light exposure and automobile driving patterns. Though left-right ratios have previously correlated with the side men or women tend to position themselves or countries drive on, more recent trends indicate a consistent left-sided bias. To clarify reasons for changing trends, a review of the evidence base and LM’s laterality in a UK cohort (99 cases 2000–2011 was conducted for the first time. The strong correlation of left-sided excess, found in both genders (ratios 1.381–1.5, P<0.05  X2 0.841, is congruent with more recent findings. Though evidence indicates that driving position is no longer a risk factor for LM, due most likely to improved car window UV protection, it remains the most commonly attributed cause. Understanding phenomena such as UV lights “scatter effect” or that cumulative exposure may not be a significant risk factor helps rationalize older conclusions that would otherwise appear contradictory. The reasons for left-sided excess remain unclear but may be due to factors requiring further research such as the body’s anatomical/embryological asymmetry.

Generalized Truncated Methods for an Efficient Solution of Retrial Systems

Directory of Open Access Journals (Sweden)

Ma Jose Domenech-Benlloch

2008-01-01

Full Text Available We are concerned with the analytic solution of multiserver retrial queues including the impatience phenomenon. As there are not closed-form solutions to these systems, approximate methods are required. We propose two different generalized truncated methods to effectively solve this type of systems. The methods proposed are based on the homogenization of the state space beyond a given number of users in the retrial orbit. We compare the proposed methods with the most well-known methods appeared in the literature in a wide range of scenarios. We conclude that the proposed methods generally outperform previous proposals in terms of accuracy for the most common performance parameters used in retrial systems with a moderated growth in the computational cost.

Weighing the value of memory loss in the surgical evaluation of left temporal lobe epilepsy: a decision analysis.

Science.gov (United States)

Akama-Garren, Elliot H; Bianchi, Matt T; Leveroni, Catherine; Cole, Andrew J; Cash, Sydney S; Westover, M Brandon

2014-11-01

Anterior temporal lobectomy is curative for many patients with disabling medically refractory temporal lobe epilepsy, but carries an inherent risk of disabling verbal memory loss. Although accurate prediction of iatrogenic memory loss is becoming increasingly possible, it remains unclear how much weight such predictions should have in surgical decision making. Here we aim to create a framework that facilitates a systematic and integrated assessment of the relative risks and benefits of surgery versus medical management for patients with left temporal lobe epilepsy. We constructed a Markov decision model to evaluate the probabilistic outcomes and associated health utilities associated with choosing to undergo a left anterior temporal lobectomy versus continuing with medical management for patients with medically refractory left temporal lobe epilepsy. Three base-cases were considered, representing a spectrum of surgical candidates encountered in practice, with varying degrees of epilepsy-related disability and potential for decreased quality of life in response to post-surgical verbal memory deficits. For patients with moderately severe seizures and moderate risk of verbal memory loss, medical management was the preferred decision, with increased quality-adjusted life expectancy. However, the preferred choice was sensitive to clinically meaningful changes in several parameters, including quality of life impact of verbal memory decline, quality of life with seizures, mortality rate with medical management, probability of remission following surgery, and probability of remission with medical management. Our decision model suggests that for patients with left temporal lobe epilepsy, quantitative assessment of risk and benefit should guide recommendation of therapy. In particular, risk for and potential impact of verbal memory decline should be carefully weighed against the degree of disability conferred by continued seizures on a patient-by-patient basis. Wiley

Cap integration in spectral gravity forward modelling: near- and far-zone gravity effects via Molodensky's truncation coefficients

Science.gov (United States)

Bucha, Blažej; Hirt, Christian; Kuhn, Michael

2018-04-01

Spectral gravity forward modelling is a technique that converts a band-limited topography into its implied gravitational field. This conversion implicitly relies on global integration of topographic masses. In this paper, a modification of the spectral technique is presented that provides gravity effects induced only by the masses located inside or outside a spherical cap centred at the evaluation point. This is achieved by altitude-dependent Molodensky's truncation coefficients, for which we provide infinite series expansions and recurrence relations with a fixed number of terms. Both representations are generalized for an arbitrary integer power of the topography and arbitrary radial derivative. Because of the altitude-dependency of the truncation coefficients, a straightforward synthesis of the near- and far-zone gravity effects at dense grids on irregular surfaces (e.g. the Earth's topography) is computationally extremely demanding. However, we show that this task can be efficiently performed using an analytical continuation based on the gradient approach, provided that formulae for radial derivatives of the truncation coefficients are available. To demonstrate the new cap-modified spectral technique, we forward model the Earth's degree-360 topography, obtaining near- and far-zone effects on gravity disturbances expanded up to degree 3600. The computation is carried out on the Earth's surface and the results are validated against an independent spatial-domain Newtonian integration (1 μGal RMS agreement). The new technique is expected to assist in mitigating the spectral filter problem of residual terrain modelling and in the efficient construction of full-scale global gravity maps of highest spatial resolution.

Left ventricular filling under elevated left atrial pressure

Science.gov (United States)

Gaddam, Manikantam; Samaee, Milad; Santhanakrishnan, Arvind

2017-11-01

Left atrial pressure (LAP) is elevated in diastolic dysfunction, where left ventricular (LV) filling is impaired due to increase in ventricular stiffness. The impact of increasing LAP and LV stiffness on intraventricular filling hemodynamics remains unclear. We conducted particle image velocimetry and hemodynamics measurements in a left heart simulator (LHS) under increasing LAP and LV stiffness at a heart rate of 70 bpm. The LHS consisted of a flexible-walled LV physical model fitted within a fluid-filled chamber. LV wall motion was generated by a piston pump that imparted pressure fluctuations in the chamber. Resistance and compliance elements in the flow loop were adjusted to obtain bulk physiological hemodynamics in the least stiff LV model. Two LV models of increasing stiffness were subsequently tested under unchanged loop settings. LAP was varied between 5-20 mm Hg for each LV model, by adjusting fluid level in a reservoir upstream of the LV. For constant LV stiffness, increasing LAP lowered cardiac output (CO), while ejection fraction (EF) and E/A ratio were increased. For constant LAP, increasing LV stiffness lowered CO and EF, and increased E/A ratio. The implications of these altered hemodynamics on intraventricular filling vortex characteristics will be presented.

Remote Left Ventricular Hemodynamic Monitoring Using a Novel Intracardiac Sensor.

Science.gov (United States)

Mondritzki, Thomas; Boehme, Philip; White, Jason; Park, Jin Woo; Hoffmann, Jessica; Vogel, Julia; Kolkhof, Peter; Walsh, Stuart; Sandner, Peter; Bischoff, Erwin; Dinh, Wilfried; Hüser, Jörg; Truebel, Hubert

2018-05-01

Heart failure (HF) remains the most common reason for hospital admission in patients aged >65 years. Despite modern drug therapy, mortality and readmission rates for patients hospitalized with HF remain high. This necessitates further research to identify early patients at risk for readmission to limit hospitalization by timely adjustment of medical therapy. Implantable devices can monitor left ventricular (LV) hemodynamics and remotely and continuously detect the early signs of decompensation to trigger interventions and reduce the risk of hospitalization for HF. Here, we report the first preclinical study validating a new batteryless and easy to implant LV-microelectromechanical system to assess LV performance. A miniaturized implantable wireless pressure sensor was adapted for implantation in the LV apex. The LV-microelectromechanical system sensor was tested in a canine model of HF. The wireless pressure sensor measurements were compared with invasive left heart catheter-derived measurements at several time points. During different pharmacological challenge studies with dobutamine or vasopressin, the device was equally sensitive compared with invasive standard procedures. No adverse events or any observable reaction related to the implantation and application of the device for a period of 35 days was observed. Our miniaturized wireless pressure sensor placed in the LV (LV-microelectromechanical system) has the potential to become a new telemetric tool to earlier identify patients at risk for HF decompensation and to guide the treatment of patients with HF. © 2018 American Heart Association, Inc.

Quantitative description of the regional mechanics of the left atria by electroanatomical mapping

International Nuclear Information System (INIS)

Kuklik, Pawel; Molaee, Payman; Brooks, Anthony G; John, Bobby; Worthley, Stephen G; Sanders, Prashanthan

2010-01-01

The left atrium is a complex chamber, which plays an integral role in the maintenance of physiologic hemodynamic and electrical stability of the heart and is involved in many disease states, most commonly atrial fibrillation. Preserving regions of the left atrium that contribute the greatest to atrial mechanical function during curative strategies for atrial fibrillation are important. We present here a new application of the CARTO electroanatomical mapping system in the assessment of the left atria mechanical function. Electroanatomical data were collected in course of the electrophysiological procedure in 11 control patients and 12 patients with paroxysmal atrial fibrillation. The three-dimensional geometry of the left atria was reconstructed in 10 ms intervals and segmented into distinct regions. For each segment, a regional ejection fraction was calculated. We found that anterior, septal and lateral segments have significantly greater regional ejection fraction than atria roof, inferior and posterior segments. Therefore, we hypothesize that in order to minimize the impact on atrial mechanical function, an important determinant of thromboembolic risk, damage should be minimized to these atrial regions

Can we reduce the risk of disease heart in treatments of left breast? bated breath; Podemos reducir el riesgo de enfermedad cardiaca en tratamientos de mama izquierda? respiracion contenida

Energy Technology Data Exchange (ETDEWEB)

Fuentemilla Urio, N.; Lozares Cordero, S.; Otal Palacin, A.; Olasolo Alonso, J.; Pellejero Pellejero, S.; Martin Albina, M. L.; Maneru Camara, F.; Miquelez Alonso, S.; Rubio Arroniz, T.; Soto Prados, P.

2013-07-01

In studies related to breast cancer and mortality, there has been an increase in the mortality of patients with survival greater than 10 years treated with radiotherapy. Subsequent studies it appears that the main cause is heart disease. Therefore, that the heart started to consider organ of risk in the treatment of breast cancer with radiation therapy (adjuvant). Reducing the doses both heart and coronary arteries leads to a reduction in the risk of heart disease. Currently are introducing new techniques, to reduce the dose in heart and in the left anterior descending coronary artery such as new positions or techniques of Breath bated breath hold... (Author)

Left ventricular structural and functional characteristics in Cushing's syndrome.

Science.gov (United States)

Muiesan, Maria Lorenza; Lupia, Mario; Salvetti, Massimo; Grigoletto, Consuelo; Sonino, Nicoletta; Boscaro, Marco; Rosei, Enrico Agabiti; Mantero, Franco; Fallo, Francesco

2003-06-18

This study was designed to evaluate left ventricular (LV) anatomy and function in patients with Cushing's syndrome. A high prevalence of LV hypertrophy and concentric remodeling has been reported in Cushing's syndrome, although no data have been reported on LV systolic and diastolic function. Forty-two consecutive patients with Cushing's syndrome and 42 control subjects, matched for age, gender, and blood pressure, were studied. Left ventricular mass index (LVMI) and relative wall thickness (RWT) were measured by echocardiography, endocardial and midwall fractional shortening (FS) were assessed, and diastolic filling was measured by Doppler transmitral flow. The RWT was significantly greater in Cushing patients than in controls. Left ventricular hypertrophy and concentric remodeling were observed in 10 and 26 patients with Cushing's syndrome, respectively. In Cushing patients, midwall FS was significantly reduced compared with controls (16.2 +/- 3% vs. 21 +/- 4.5%, p = 0.01). The ratio of transmitral E and A flow velocities was reduced and E deceleration time was prolonged in Cushing patients compared with controls (p = 0.03 and p < 0.001, respectively). In patients with Cushing's syndrome, cardiac structural changes are associated with reduced midwall systolic performance and with diastolic dysfunction that may contribute to the high risk of cardiovascular events observed in these patients.

Left ventricular dimensions, systolic functions, and mass in term neonates with symmetric and asymmetric intrauterine growth restriction.

Science.gov (United States)

Cinar, Bahar; Sert, Ahmet; Gokmen, Zeynel; Aypar, Ebru; Aslan, Eyup; Odabas, Dursun

2015-02-01

Previous studies have demonstrated structural changes in the heart and cardiac dysfunction in foetuses with intrauterine growth restriction. There are no available data that evaluated left ventricular dimensions and mass in neonates with symmetric and asymmetric intrauterine growth restriction. Therefore, we aimed to evaluate left ventricular dimensions, systolic functions, and mass in neonates with symmetric and asymmetric intrauterine growth restriction. We also assessed associated maternal risk factors, and compared results with healthy appropriate for gestational age neonates. In all, 62 asymmetric intrauterine growth restriction neonates, 39 symmetric intrauterine growth restriction neonates, and 50 healthy appropriate for gestational age neonates were evaluated by transthoracic echocardiography. The asymmetric intrauterine growth restriction group had significantly lower left ventricular end-systolic and end-diastolic diameters and posterior wall diameter in systole and diastole than the control group. The symmetric intrauterine growth restriction group had significantly lower left ventricular end-diastolic diameter than the control group. All left ventricular dimensions were lower in the asymmetric intrauterine growth restriction neonates compared with symmetric intrauterine growth restriction neonates (p>0.05), but not statistically significant except left ventricular posterior wall diameter in diastole (3.08±0.83 mm versus 3.54 ±0.72 mm) (pintrauterine growth restriction groups had significantly lower relative posterior wall thickness (0.54±0.19 versus 0.48±0.13 versus 0.8±0.12), left ventricular mass (9.8±4.3 g versus 8.9±3.4 g versus 22.2±5.7 g), and left ventricular mass index (63.6±29.1 g/m2 versus 54.5±24.4 g/m2 versus 109±28.8 g/m2) when compared with the control group. Our study has demonstrated that although neonates with both symmetric and asymmetric intrauterine growth restriction had lower left ventricular dimensions, relative

Molecular evolution of pentatricopeptide repeat genes reveals truncation in species lacking an editing target and structural domains under distinct selective pressures

Directory of Open Access Journals (Sweden)

Hayes Michael L

2012-05-01

Full Text Available Abstract Background Pentatricopeptide repeat (PPR proteins are required for numerous RNA processing events in plant organelles including C-to-U editing, splicing, stabilization, and cleavage. Fifteen PPR proteins are known to be required for RNA editing at 21 sites in Arabidopsis chloroplasts, and belong to the PLS class of PPR proteins. In this study, we investigate the co-evolution of four PPR genes (CRR4, CRR21, CLB19, and OTP82 and their six editing targets in Brassicaceae species. PPR genes are composed of approximately 10 to 20 tandem repeats and each repeat has two α-helical regions, helix A and helix B, that are separated by short coil regions. Each repeat and structural feature was examined to determine the selective pressures on these regions. Results All of the PPR genes examined are under strong negative selection. Multiple independent losses of editing site targets are observed for both CRR21 and OTP82. In several species lacking the known editing target for CRR21, PPR genes are truncated near the 17th PPR repeat. The coding sequences of the truncated CRR21 genes are maintained under strong negative selection; however, the 3’ UTR sequences beyond the truncation site have substantially diverged. Phylogenetic analyses of four PPR genes show that sequences corresponding to helix A are high compared to helix B sequences. Differential evolutionary selection of helix A versus helix B is observed in both plant and mammalian PPR genes. Conclusion PPR genes and their cognate editing sites are mutually constrained in evolution. Editing sites are frequently lost by replacement of an edited C with a genomic T. After the loss of an editing site, the PPR genes are observed with three outcomes: first, few changes are detected in some cases; second, the PPR gene is present as a pseudogene; and third, the PPR gene is present but truncated in the C-terminal region. The retention of truncated forms of CRR21 that are maintained under strong negative

Molecular evolution of pentatricopeptide repeat genes reveals truncation in species lacking an editing target and structural domains under distinct selective pressures.

Science.gov (United States)

Hayes, Michael L; Giang, Karolyn; Mulligan, R Michael

2012-05-14

Pentatricopeptide repeat (PPR) proteins are required for numerous RNA processing events in plant organelles including C-to-U editing, splicing, stabilization, and cleavage. Fifteen PPR proteins are known to be required for RNA editing at 21 sites in Arabidopsis chloroplasts, and belong to the PLS class of PPR proteins. In this study, we investigate the co-evolution of four PPR genes (CRR4, CRR21, CLB19, and OTP82) and their six editing targets in Brassicaceae species. PPR genes are composed of approximately 10 to 20 tandem repeats and each repeat has two α-helical regions, helix A and helix B, that are separated by short coil regions. Each repeat and structural feature was examined to determine the selective pressures on these regions. All of the PPR genes examined are under strong negative selection. Multiple independent losses of editing site targets are observed for both CRR21 and OTP82. In several species lacking the known editing target for CRR21, PPR genes are truncated near the 17th PPR repeat. The coding sequences of the truncated CRR21 genes are maintained under strong negative selection; however, the 3' UTR sequences beyond the truncation site have substantially diverged. Phylogenetic analyses of four PPR genes show that sequences corresponding to helix A are high compared to helix B sequences. Differential evolutionary selection of helix A versus helix B is observed in both plant and mammalian PPR genes. PPR genes and their cognate editing sites are mutually constrained in evolution. Editing sites are frequently lost by replacement of an edited C with a genomic T. After the loss of an editing site, the PPR genes are observed with three outcomes: first, few changes are detected in some cases; second, the PPR gene is present as a pseudogene; and third, the PPR gene is present but truncated in the C-terminal region. The retention of truncated forms of CRR21 that are maintained under strong negative selection even in the absence of an editing site target

Improved catalytic efficiency, thermophilicity, anti-salt and detergent tolerance of keratinase KerSMD by partially truncation of PPC domain.

Science.gov (United States)

Fang, Zhen; Zhang, Juan; Du, Guocheng; Chen, Jian

2016-06-14

The keratinase from Stenotrophomonas maltophilia (KerSMD) is known for its high activity and pH stability in keratin degradation. However, catalytic efficiency and detergent tolerability need to be improved in order to be used for industrial application. In this work, we obtained several keratinase variants with enhanced catalytic efficiency, thermophilicity, and anti-salt and detergent tolerability by partially truncating the PPC domain of KerSMD. The variants all showed improved catalytic efficiency to synthetic substrate AAPF, with the V355 variant having the highest kcat /Km value of 143.6 s(-1) mM(-1). The truncation of keratinase had little effect on alkaline stability but obviously decreased collagenase activity, developing its potential application in leather treatment. The variants V380, V370, and V355 were thermophilic, with a 1.7-fold enhancement of keratinlytic activity at 60 °C when compared to the wild type. The entire truncation of PPC domain obtained the variant V355 with improved tolerance to alkalinity, salt, chaotropic agents, and detergents. The V355 variant showed more than a 40% improvement in activity under 15% (w/v) NaCl or 4% (w/v) SDS solution, showing excellent stability under harsh washing and unhairing conditions. Our work investigated how protein engineering affects the function of PPC domain of KerSMD.

Topography of the accessory left gastric artery (ALGA) analyzed by CT angiography from the left hepatic artery

International Nuclear Information System (INIS)

Shioyama, Yasukazu; Takasaka, Isao; Onaya, Hiroaki

2003-01-01

To avoid gastric complications when we perform transcatheter treatment via left hepatic artery, we analyzed the topography of ALGA (accessory left gastric artery) by left hepatic arteriography and CT angiography from left hepatic artery. Six hundred seventy eight cases of CT angiography were performed between 1995 and 2000. Among them, selective left hepatic arteriography was done in 85 cases. We analyzed the frequency and the course of ALGA on the hepatic angiogram and CT angiogram. ALGA were identified in eighteen (21.2 %) of the 85 cases. We classified them into eleven cases of the proximal type and six cases of the distal type. When ALGA bifurcated from the left hepatic artery very close to the bifurcation of A2 (dorsolateral branch) and A3 (ventrolateral branch), we classified them as the distal type on hepatic angiogram. On the other hand, when ALGA bifurcated from the left hepatic artery apart from the bifurcation of A2 and A3 they were classified as the proximal type. In one rare case ALGA originated from the dorsolateral branch of the left hepatic artery. ALGA were classified as the distal and proximal types. Distal type of ALGA often overlapped dorsolateral branch of the left hepatic artery, and it was sometimes difficult to notice the existence of them. We should check the existence of ALGA on the arterial phase of dynamic CT before we plan to make a transcatheter treatment from the left hepatic artery. Then we can avoid gastric complications caused by a transcatheter treatment from the left hepatic artery. (author)

A Case of Left Renal Vein Ligation in a Patient with Solitary Left Kidney Undergoing Liver Transplantation to Control Splenorenal Shunt and Improve Portal Venous Flow.

Science.gov (United States)

Martino, Rodrigo B; Júnior, Eserval Rocha; Manuel, Valdano; Rocha-Santos, Vinicius; D'Albuquerque, Luis Augusto C; Andraus, Wellington

2017-10-11

BACKGROUND Adequate portal venous flow is required for successful liver transplantation. Reduced venous flow and blood flow 'steal' by collateral vessels are a concern, and when there is a prominent splenorenal shunt present, ligation of the left renal vein has been recommended to improve portal venous blood flow. CASE REPORT A 51-year-old man who had undergone right nephrectomy in childhood required liver transplantation for liver cirrhosis and hepatocellular carcinoma due to hepatitis C virus (HCV) infection. The patient had no other comorbidity and no history of hepatorenal syndrome. At transplantation surgery, portal venous flow was poor and did not improve with ligation of shunt veins, but ligation of the left renal vein improved portal venous flow. On the first and fifth postoperative days, the patient was treated with basiliximab, a chimeric monoclonal antibody to the IL-2 receptor, and methylprednisolone. The calcineurin inhibitor, tacrolimus, was introduced on the fifth postoperative day. On the sixteenth postoperative day, renal color Doppler ultrasound showed normal left renal parenchyma; hepatic Doppler ultrasound showed good portal vein flow and preserved hepatic parenchyma in the liver transplant. CONCLUSIONS This case report has shown that in a patient with a single left kidney, left renal vein ligation is feasible and safe in a patient with no other risk factors for renal impairment following liver transplantation. Modification of postoperative immunosuppression to avoid calcineurin inhibitors in the very early postoperative phase may be important in promoting good recovery of renal function and to avoid the need for postoperative renal dialysis.

Left Atrial Decompression by Percutaneous Left Atrial Venting Cannula Insertion during Venoarterial Extracorporeal Membrane Oxygenation Support

Directory of Open Access Journals (Sweden)

Ha Eun Kim

2016-06-01

Full Text Available Patients with venoarterial extracorporeal membrane oxygenation (ECMO frequently suffer from pulmonary edema due to left ventricular dysfunction that accompanies left heart dilatation, which is caused by left atrial hypertension. The problem can be resolved by left atrium (LA decompression. We performed a successful percutaneous LA decompression with an atrial septostomy and placement of an LA venting cannula in a 38-month-old child treated with venoarterial ECMO for acute myocarditis.

Social aspects of left-handedness

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Belojević Goran

2010-01-01

Full Text Available Throughout human history left-handedness has been considered as sinful. It has been associated with the devil, weakness, female gender, unhealthiness, evil, something that has to be turned to a “good” - right side by force. Left-handedness is being more and more acceptable at rational level, but in everyday life it is still considered to be unusual if someone writes with the left hand. Lessening of the number of lefthanders is associated with ageing. There are about 13% lefthanders among people in twenties and less than 1% lefthanders among those in eighties. This finding may be explaned with more pronounced socio-cultural pressure on left-handed people in the past, compared to nowadays. On the other hand, this may also support the hypothesis about a reduced life span of lefthanded people. With cross-exercising of left-handedness, certain typical characteristics and behavioral patterns appear in these people. This was a sort of provoked behavior and an attack on the integrity of an emotional attitude toward oneself. Stuttering may also appear as a consequence of unsuccessful cross-exercising of left-handedness. The hypothesis about left-handedness as an advantage is supported with the reports about relatively more lefthanders in some specific groups such as: mathematicians, sculptors, architects, painters, musicians, actors, tennis players, as well as famous army commanders and rulers.

Effects of truncation of the peptide chain on the secondary structure and bioactivities of palmitoylated anoplin.

Science.gov (United States)

Salas, Remmer L; Garcia, Jan Kathryne D L; Miranda, Ana Carmela R; Rivera, Windell L; Nellas, Ricky B; Sabido, Portia Mahal G

2018-06-01

Anoplin (GLLKRIKTLL-NH 2 ) is of current interest due to its short sequence and specificity towards bacteria. Recent studies on anoplin have shown that truncation and acylation compromises its antimicrobial activity and specificity, respectively. In this study, truncated analogues (pal-ano-9 to pal-ano-5) of palmitoylated anoplin (pal-anoplin) were synthesized to determine the effects of C-truncation on its bioactivities. Moreover, secondary structure of each analogue using circular dichroism (CD) spectroscopy was determined to correlate with bioactivities. Interestingly, pal-anoplin, pal-ano-9 and pal-ano-6 were helical in water, unlike anoplin. In contrast, pal-ano-8, pal-ano-7 and pal-ano-5, with polar amino acid residues at the C-terminus, were random coil in water. Nevertheless, all the peptides folded into helical structures in 30% trifluoroethanol/water (TFE/H 2 O) except for the shortest analogue pal-ano-5. Hydrophobicity played a significant role in the enhancement of activity against bacteria E. coli and S. aureus as all lipopeptides including the random coil pal-ano-5 were more active than the parent anoplin. Meanwhile, the greatest improvement in activity against the fungus C. albicans was observed for pal-anoplin analogues (pal-ano-9 and pal-ano-6) that were helical in water. Although, hydrophobicity is a major factor in the secondary structure and antimicrobial activity, it appears that the nature of amino acids at the C-terminus also influence folding of lipopeptides in water and its antifungal activity. Moreover, the hemolytic activity of the analogues was found to correlate with hydrophobicity, except for the least hemolytic, pal-ano-5. Since most of the analogues are more potent and shorter than anoplin, they are promising drug candidates for further development. Copyright © 2018. Published by Elsevier Inc.

Truncation of the many body hierarchy and relaxation times in the McKean model

International Nuclear Information System (INIS)

Schmitt, K.J.

1987-01-01

In the McKean model the BBGKY-hierarchy is equivalent to a simple hierarchy of coupled equations for the p-particle correlation functions. Truncation effects and the convergence of the one-particle distribution towards its exact shape have been studied. In the long time limit the equations can be solved in a closed form. It turns out that the p-particle correlation decays p-times faster than the non-equilibrium one-particle distribution

TRUNCATION OF THE MANY BODY HIERARCHY AND RELAXATION TIMES IN THE McKEAN MODEL

OpenAIRE

Schmitt , K.-J.

1987-01-01

In the McKean model the BBGKY-hierarchy is equivalent to a simple hierarchy of coupled equations for the p-particle correlation functions. Truncation effects and the convergence of the one-particle distribution towards its exact shape have been studied. In the long time limit the equations can be solved in a closed form. It turns out that the p-particle correlation decays p-times faster than the non-equilibrium one-particle distribution.

Pair truncation for rotational nuclei: j=17/2 model

International Nuclear Information System (INIS)

Halse, P.; Jaqua, L.; Barrett, B.R.

1989-01-01

The suitability of the pair condensate approach for rotational states is studied in a single j=17/2 shell of identical nucleons interacting through a quadrupole-quadrupole Hamiltonian. The ground band and a K=2 excited band are both studied in detail. A direct comparison of the exact states with those constituting the SD and SDG subspaces is used to identify the important degrees of freedom for these levels. The range of pairs necessary for a good description is found to be highly state dependent; S and D pairs are the major constituents of the low-spin ground-band levels, while G pairs are needed for those in the γ band. Energy spectra are obtained for each truncated subspace. SDG pairs allow accurate reproduction of the binding energy and K=2 excitation energy, but still give a moment of inertia which is about 30% too small even for the lowest levels

Relationship between occupational exposure to lead and local arterial stiffness and left ventricular diastolic function in individuals with arterial hypertension

International Nuclear Information System (INIS)

Poreba, Rafal; Gac, Pawel; Poreba, Malgorzata; Antonowicz-Juchniewicz, Jolanta; Andrzejak, Ryszard

2011-01-01

Relationship between occupational exposure to lead and frequency of complications in persons with arterial hypertension has been poorly investigated. This study aimed at evaluation of the relationship between occupational exposure to lead and manifestation of an increased local arterial stiffness and left ventricular diastolic dysfunction. The studies included 105 men (mean age: 44.47 ± 9.12 years) with arterial hypertension, treated with hypotensive drugs: group I - men occupationally exposed to lead (n = 53), and group II - men not exposed to lead (n = 52). In echocardiographic examination, the left ventricular diastolic dysfunction was diagnosed significantly more frequently in group I than in group II. In eTracking examination mean values of stiffness parameter (β), augmentation index (AI) and one-point pulse wave velocity (PWV-β) were significantly higher and mean values of arterial compliance (AC) were significantly lower in group I than in group II. The logistic regression showed that in the group of persons with arterial hypertension occupationally exposed to lead a more advanced age, higher blood lead concentration and higher mean values of augmentation index represent independent risk factors of left ventricular diastolic dysfunction. The multifactorial regression showed that amongst persons with arterial hypertension occupationally exposed to lead higher blood zinc protoporphyrin concentration, a more advanced age and higher value of body mass index (BMI) represent independent risk factors of an increased local arterial stiffness. In summary, we should note that in the group of persons with arterial hypertension occupationally exposed to lead the study has demonstrated a significantly more frequent manifestation of left ventricular diastolic dysfunction and an increase in local arterial stiffness. - Highlights: → Amongst persons with AH exposed to Pb higher ZnPP represent independent risk factor of increased local arterial stiffness. → Higher Pb

Expression of a truncated Hmga1b gene induces gigantism, lipomatosis and B-cell lymphomas in mice.

Science.gov (United States)

Fedele, Monica; Visone, Rosa; De Martino, Ivana; Palmieri, Dario; Valentino, Teresa; Esposito, Francesco; Klein-Szanto, Andres; Arra, Claudio; Ciarmiello, Andrea; Croce, Carlo M; Fusco, Alfredo

2011-02-01

HMGA1 gene rearrangements have been frequently described in human lipomas. In vitro studies suggest that HMGA1 proteins have a negative role in the control of adipocyte cell growth, and that HMGA1 gene truncation acts in a dominant-negative fashion. Therefore, to define better the role of the HMGA1 alterations in the generation of human lipomas, we generated mice carrying an Hmga1b truncated (Hmga1b/T) gene. These mice develop a giant phenotype together with a drastic expansion of the retroperitoneal and subcutaneous white adipose tissue. We show that the activation of the E2F pathway likely accounts, at least in part, for this phenotype. Interestingly, the Hmga1b/T mice also develop B-cell lymphomas similar to that occurring in Hmga1-knockout mice, supporting a dominant-negative role of the Hmga1b/T mutant also in vivo. Copyright © 2010 Elsevier Ltd. All rights reserved.

Influence of surgical implantation angle of left ventricular assist device outflow graft and management of aortic valve opening on the risk of stroke in heart failure patients

Science.gov (United States)

Chivukula, V. Keshav; McGah, Patrick; Prisco, Anthony; Beckman, Jennifer; Mokadam, Nanush; Mahr, Claudius; Aliseda, Alberto

2016-11-01

Flow in the aortic vasculature may impact stroke risk in patients with left ventricular assist devices (LVAD) due to severely altered hemodynamics. Patient-specific 3D models of the aortic arch and great vessels were created with an LVAD outflow graft at 45, 60 and 90° from centerline of the ascending aorta, in order to understand the effect of surgical placement on hemodynamics and thrombotic risk. Intermittent aortic valve opening (once every five cardiac cycles) was simulated and the impact of this residual native output investigated for the potential to wash out stagnant flow in the aortic root region. Unsteady CFD simulations with patient-specific boundary conditions were performed. Particle tracking for 10 cardiac cycles was used to determine platelet residence times and shear stress histories. Thrombosis risk was assessed by a combination of Eulerian and Lagrangian metrics and a newly developed thrombogenic potential metric. Results show a strong influence of LVAD outflow graft angle on hemodynamics in the ascending aorta and consequently on stroke risk, with a highly positive impact of aortic valve opening, even at low frequencies. Optimization of LVAD implantation and management strategies based on patient-specific simulations to minimize stroke risk will be presented

Epidemiology of Left Ventricular Systolic Dysfunction and Heart Failure in the Framingham Study

DEFF Research Database (Denmark)

Vasan, Ramachandran S; Xanthakis, Vanessa; Lyass, Asya

2018-01-01

OBJECTIVES: The purpose of this study was to describe the temporal trends in prevalence of left ventricular systolic dysfunction (LVSD) in individuals without and with heart failure (HF) in the community over a 3-decade period of observation. BACKGROUND: Temporal trends in the prevalence and mana......OBJECTIVES: The purpose of this study was to describe the temporal trends in prevalence of left ventricular systolic dysfunction (LVSD) in individuals without and with heart failure (HF) in the community over a 3-decade period of observation. BACKGROUND: Temporal trends in the prevalence...... and management of major risk factors may affect the epidemiology of HF. METHODS: We compared the frequency, correlates, and prognosis of LVSD (left ventricular ejection fraction [LVEF] ... with LVSD (∼2- to 4-fold risk of HF or death) remained unchanged over time. Among participants with new-onset HF (n = 894, mean age 75 years, 52% women), the frequency of heart failure with preserved ejection fraction (HFpEF) increased (preserved LVEF ≥50%: 41.0% in 1985 to 1994 vs. 56.17% in 2005 to 2014...

Left ventricular assist device implantation via left thoracotomy: alternative to repeat sternotomy.

Science.gov (United States)

Pierson, Richard N; Howser, Renee; Donaldson, Terri; Merrill, Walter H; Dignan, Rebecca J; Drinkwater, Davis C; Christian, Karla G; Butler, Javed; Chomsky, Don; Wilson, John R; Clark, Rick; Davis, Stacy F

2002-03-01

Repeat sternotomy for left ventricular assist device insertion may result in injury to the right heart or patent coronary grafts, complicating intraoperative and postoperative management. In 4 critically ill patients, left thoracotomy was used as an alternative to repeat sternotomy. Anastomosis of the outflow conduit to the descending thoracic aorta provided satisfactory hemodynamic support.

N-terminal truncation enables crystallization of the receptor-binding domain of the FedF bacterial adhesin

Energy Technology Data Exchange (ETDEWEB)

De Kerpel, Maia; Van Molle, Inge [Department of Ultrastructure, Vrije Universiteit Brussel (VUB), Flanders Interuniversity Institute for Biotechnology (VIB), Pleinlaan 2, 1050 Brussels (Belgium); Brys, Lea [Department of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Flanders Interuniversity Institute for Biotechnology (VIB), Pleinlaan 2, 1050 Brussels (Belgium); Wyns, Lode; De Greve, Henri; Bouckaert, Julie, E-mail: bouckaej@vub.ac.be [Department of Ultrastructure, Vrije Universiteit Brussel (VUB), Flanders Interuniversity Institute for Biotechnology (VIB), Pleinlaan 2, 1050 Brussels (Belgium)

2006-12-01

The N-terminal receptor-binding domain of the FedF adhesin from enterotoxigenic E. coli has been crystallized. This required the deletion of its first 14 residues, which are also cleaved off naturally. FedF is the two-domain tip adhesin of F18 fimbriae from enterotoxigenic Escherichia coli. Bacterial adherence, mediated by the N-terminal receptor-binding domain of FedF to carbohydrate receptors on intestinal microvilli, causes diarrhoea and oedema disease in newly weaned piglets and induces the secretion of Shiga toxins. A truncate containing only the receptor-binding domain of FedF was found to be further cleaved at its N-terminus. Reconstruction of this N-terminal truncate rendered FedF amenable to crystallization, resulting in crystals with space group P2{sub 1}2{sub 1}2{sub 1} and unit-cell parameters a = 36.20, b = 74.64, c = 99.03 Å that diffracted to beyond 2 Å resolution. The binding specificity of FedF was screened for on a glycan array, exposing 264 glycoconjugates, to identify specific receptors for cocrystallization with FedF.

Consistent Kaluza-Klein truncations via exceptional field theory

Energy Technology Data Exchange (ETDEWEB)

Hohm, Olaf [Center for Theoretical Physics, Massachusetts Institute of Technology,Cambridge, MA 02139 (United States); Samtleben, Henning [Université de Lyon, Laboratoire de Physique, UMR 5672, CNRS,École Normale Supérieure de Lyon, 46, allée d’Italie, F-69364 Lyon cedex 07 (France)

2015-01-26

We present the generalized Scherk-Schwarz reduction ansatz for the full supersymmetric exceptional field theory in terms of group valued twist matrices subject to consistency equations. With this ansatz the field equations precisely reduce to those of lower-dimensional gauged supergravity parametrized by an embedding tensor. We explicitly construct a family of twist matrices as solutions of the consistency equations. They induce gauged supergravities with gauge groups SO(p,q) and CSO(p,q,r). Geometrically, they describe compactifications on internal spaces given by spheres and (warped) hyperboloides H{sup p,q}, thus extending the applicability of generalized Scherk-Schwarz reductions beyond homogeneous spaces. Together with the dictionary that relates exceptional field theory to D=11 and IIB supergravity, respectively, the construction defines an entire new family of consistent truncations of the original theories. These include not only compactifications on spheres of different dimensions (such as AdS{sub 5}×S{sup 5}), but also various hyperboloid compactifications giving rise to a higher-dimensional embedding of supergravities with non-compact and non-semisimple gauge groups.

VARIATION IN THE OPENINGS (OSTIA OF LEFT PULMONARY VEINS INTO THE LEFT ATRIUM: A CASE REPORT

Directory of Open Access Journals (Sweden)

Sesi

2015-03-01

Full Text Available During early embryonic development, absorption of pulmonary venous network by the left primitive atrial chamber results in opening of four pulmonary veins which drain independently into its chamber. The extent of absorption and hence, the number of pulmon ary veins which open into the left atrium, may vary. Here we report a variation in the opening of the Left upper (superior pulmonary vein into the Left atrium. A total of six openings observed

CRISPR/Cas9-induced transgene insertion and telomere-associated truncation of a single human chromosome for chromosome engineering in CHO and A9 cells.

Science.gov (United States)

Uno, Narumi; Hiramatsu, Kei; Uno, Katsuhiro; Komoto, Shinya; Kazuki, Yasuhiro; Oshimura, Mitsuo

2017-10-06

Chromosome engineering techniques including gene insertion, telomere-associated truncation and microcell-mediated chromosome transfer (MMCT) are powerful tools for generation of humanised model animal, containing megabase-sized genomic fragments. However, these techniques require two cell lines: homologous recombination (HR)-proficient DT40 cells for chromosome modification, and CHO cells for transfer to recipient cells. Here we show an improved technique using a combination of CRISPR/Cas9-induced HR in CHO and mouse A9 cells without DT40 cells following MMCT to recipient cells. Transgene insertion was performed in CHO cells with the insertion of enhanced green fluorescence protein (EGFP) using CRISPR/Cas9 and a circular targeting vector containing two 3 kb HR arms. Telomere-associated truncation was performed in CHO cells using CRISPR/Cas9 and a linearised truncation vector containing a single 7 kb HR arm at the 5' end, a 1 kb artificial telomere at the 3' end. At least 11% and 6% of the targeting efficiency were achieved for transgene insertion and telomere-associated truncation, respectively. The transgene insertion was also confirmed in A9 cells (29%). The modified chromosomes were transferrable to other cells. Thus, this CHO and A9 cell-mediated chromosome engineering using the CRISPR/Cas9 for direct transfer of the modified chromosome is a rapid technique that will facilitate chromosome manipulation.

Right colon cancer: Left behind.

Science.gov (United States)

Gervaz, P; Usel, M; Rapiti, E; Chappuis, P; Neyroud-Kaspar, I; Bouchardy, C

2016-09-01

Prognosis of colon cancer (CC) has steadily improved during the past three decades. This trend, however, may vary according to proximal (right) or distal (left) tumor location. We studied if improvement in survival was greater for left than for right CC. We included all CC recorded at the Geneva population-based registry between 1980 and 2006. We compared patients, tumor and treatment characteristics between left and right CC by logistic regression and compared CC specific survival by Cox models taking into account putative confounders. We also compared changes in survival between CC location in early and late years of observation. Among the 3396 CC patients, 1334 (39%) had right-sided and 2062 (61%) left-sided tumors. In the early 1980s, 5-year specific survival was identical for right and left CCs (49% vs. 48%). During the study period, a dramatic improvement in survival was observed for patients with left-sided cancers (Hazard ratio [HR]: 0.42, 95% confidence interval [CI]: 0.29-0.62, p colon cancer patients, those with right-sided lesions have by far the worse prognosis. Change of strategic management in this subgroup is warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

A numerical method for multigroup slab-geometry discrete ordinates problems with no spatial truncation error

International Nuclear Information System (INIS)

Barros, R.C. de; Larsen, E.W.

1991-01-01

A generalization of the one-group Spectral Green's Function (SGF) method is developed for multigroup, slab-geometry discrete ordinates (S N ) problems. The multigroup SGF method is free from spatial truncation errors; it generated numerical values for the cell-edge and cell-average angular fluxes that agree with the analytic solution of the multigroup S N equations. Numerical results are given to illustrate the method's accuracy

Left ventricular midwall mechanics at 24 weeks' gestation in high-risk normotensive pregnant women: relationship to placenta-related complications of pregnancy.

Science.gov (United States)

Novelli, G P; Vasapollo, B; Gagliardi, G; Tiralongo, G M; Pisani, I; Manfellotto, D; Giannini, L; Valensise, H

2012-04-01

Most studies during pregnancy have assessed maternal left ventricular (LV) function by load-dependent indices, assessing only chamber function. The aim of this study was to assess afterload-adjusted LV myocardial and chamber systolic function at 24 weeks' gestation and 6 months postpartum in high-risk normotensive pregnant women. A group of 118 high-risk women with bilateral notching of the uterine arteries underwent an echocardiographic examination to evaluate midwall mechanics (midwall shortening (mFS%) and stress-corrected midwall shortening (SCmFS%)) of the LV at 24 weeks' gestation and 6 months postpartum. Patients were followed until delivery and pregnancies were classified retrospectively as uneventful (uncomplicated outcome) or complicated. A control group of 54 low-risk women with uneventful pregnancies without bilateral notching was also enrolled. The pregnancy was uneventful in 74 (62.7%) women, whereas 44 (37.3%) developed complications. At 24 weeks' gestation, mFS% and SCmFS% were greater in the uncomplicated-outcome compared with the complicated-outcome group (25.9 ± 4.8 vs 18.8 ± 5.0%, P SCmFS% remained greater in the uncomplicated-outcome compared with the complicated-outcome group (100.4 ± 21.6 vs 87.8 ± 19.1, P SCmFS% was higher during pregnancy than it was postpartum, whereas in the complicated-outcome group, it was lower during pregnancy than it was postpartum (P SCmFS% increased compared with controls) during pregnancy compared with postpartum in high-risk patients with uncomplicated pregnancy, whereas midwall mechanics are depressed both during pregnancy and postpartum in patients with pregnancy complications. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

Design and Synthesis of a Series of Truncated Neplanocin Fleximers

Directory of Open Access Journals (Sweden)

Sarah C. Zimmermann

2014-12-01

Full Text Available In an effort to study the effects of flexibility on enzyme recognition and activity, we have developed several different series of flexible nucleoside analogues in which the purine base is split into its respective imidazole and pyrimidine components. The focus of this particular study was to synthesize the truncated neplanocin A fleximers to investigate their potential anti-protozoan activities by inhibition of S-adenosylhomocysteine hydrolase (SAHase. The three fleximers tested displayed poor anti-trypanocidal activities, with EC50 values around 200 μM. Further studies of the corresponding ribose fleximers, most closely related to the natural nucleoside substrates, revealed low affinity for the known T. brucei nucleoside transporters P1 and P2, which may be the reason for the lack of trypanocidal activity observed.

Emotional and behavioral problems of Chinese left-behind children: a preliminary study.

Science.gov (United States)

Fan, Fang; Su, Linyan; Gill, Mary Kay; Birmaher, Boris

2010-06-01

To examine the behavioral and emotional problems and their correlates in left-behindchildren (LBC) in the Hunan Province of China. A sample of 1,274 schoolchildren (48.7% girls; 12.4 +/- 2.2 years old) completed the Strength and Difficulties Questionnaire and their current caregivers completed questionnaires about caregiver/bio-parent's demographics and teachers' involvement with the family. There were 629 (49%) children with a history of being left behind, of which 486 were currently cared for by a relative (RLC) and 41 by a non-relative (NRC). As much as 102 had a past history of being left behind, but were currently living with one or more biological parents at the time of the survey (PLB). A total of 645 (51%) children had no history of being left behind and were included as controls. LBC had significantly more psychopathology and less pro-social behaviors than the controls. These differences, with the exception of more hyperactivity and less pro-social behaviors, disappeared after adjusting for age, education and socioeconomic status of the children, parents/caregivers, and the involvement of the teachers. The psychopathology of LBC was significantly inversely correlated with these variables. Long duration and being left behind at a younger age were significantly associated with more psychopathology. Overall, NRC showed more psychopathology, followed by PLB and then RLC. However, with the exception of pro-social behaviors, after adjusting for demographic variables and duration of being left behind, all differences disappeared. LBC are at risk to develop emotional/behavior problems, particularly if they are left behind early in life, for longer periods, in the care of young caregivers or nonrelatives with poor education and low socioeconomic status, and with less teacher support. Strategies to prevent the development of psychopathology and its amelioration, and governmental policies to decrease the rates of LBC are warranted.

The effect of percutaneous transcatheter occlusion of left atrial appendage on left atrium and adjacent anatomic structure in canine

International Nuclear Information System (INIS)

Yang Zhihong; Wu Hong; Qin Yongwen; Hu Jianqiang; Ding Zhongru; Liu Zongjun; Liu Biao; Zheng Xing

2009-01-01

Objective: To observe the effect of percutaneous transcatheter occlusion of left atrial appendage (LAA) with a new self-manufactured LAA occluder on left atrium and adjacent anatomic structure in canine. Methods: A new self-manufactured LAA occluder was implanted into the LAA through a transseptal catheter in 20 dogs. Before and after the procedure, the experimental dogs were anaesthetized and examined by transthoracic echocardiography (TTE) to measure the diameter and the volume of the left atrium, the left superior pulmonary vein flow velocity and the left atrioventricular valve flow velocity separately. The contrast radiography of the LAA and the left coronary arteriography were performed. Results: The new LAA occluder was implanted successfully in 14 dogs. No obvious changes in the diameter and the volume of the left atrium, in left superior pulmonary vein flow velocity and in left atrioventricular valve flow velocity were found. On arteriography, left circumflex artery was normally displayed after the procedure. No migration of the occluder was seen on TTE and angiography after procedure. Conclusion: Percutaneous transcatheter occlusion of left atrial appendage with a new self-manufactured LAA occluder has no obvious effect on left atrium and adjacent anatomic structure in experimental canine, which indicates that the new-type device is a safe and feasible occluder for LAA. (authors)

The robustness of truncated Airy beam in PT Gaussian potentials media

Science.gov (United States)

Wang, Xianni; Fu, Xiquan; Huang, Xianwei; Yang, Yijun; Bai, Yanfeng

2018-03-01

The robustness of truncated Airy beam in parity-time (PT) symmetric Gaussian potentials media is numerically investigated. A high-peak power beam sheds from the Airy beam due to the media modulation while the Airy wavefront still retain its self-bending and non-diffraction characteristics under the influence of modulation parameters. Increasing the modulation factor results in the smaller value of maximum power of the center beam, and the opposite trend occurs with the increment of the modulation depth. However, the parabolic trajectory of the Airy wavefront does not be influenced. By utilizing the unique features, the Airy beam can be used as a long distance transmission source under the PT symmetric Gaussian potentials medium.

Pulse column hydrodynamics for liquid-liquid extraction with truncated-disc packing

International Nuclear Information System (INIS)

Bracou, H.; Hanssens, A.

1993-01-01

The experimental installation is composed of a stainless steel truncated disc packing with 25% of axial transparency, 25 mm of distance between the plates and 50 mm of diameter (DT 25/25/50 stainless steel). The phase system used during these tests is the hydrogenated tetra-propylene (HTP dispersed phase) /water (continuous phase) in continuous aqueous operating ''FAC'' method. The aim of this work is to gather the whole requisite data to the modelization stage based on the extrapolation of a mathematical tool, type population evaluation with a double object to supply the basis information useful for the model, and to establish an experimental data base for the model validation. 9 refs., 4 figs

Autonomic Predictors of Hospitalization Due to Heart Failure Decompensation in Patients with Left Ventricular Systolic Dysfunction.

Directory of Open Access Journals (Sweden)

Ludmiła Daniłowicz-Szymanowicz

Full Text Available Autonomic nervous system balance can be significantly deteriorated during heart failure exacerbation. However, it is still unknown whether these changes are only the consequence of heart failure decompensation or can also predict development thereof. Objectives were to verify if simple, non-invasive autonomic parameters, such as baroreflex sensitivity and short-term heart rate variability can provide independent of other well-known clinical parameters information on the risk of heart failure decompensation in patients with left ventricular systolic dysfunction.In 142 stable patients with left ventricular ejection fraction ≤ 40%, baroreflex sensitivity and short-term heart rate variability, as well as other well-known clinical parameters, were analyzed. During 23 ± 9 months of follow-up 19 patients were hospitalized due to the heart failure decompensation (EVENT.Pre-specified cut-off values of baroreflex sensitivity (≤2.4 ms/mmHg and low frequency power index of heart rate variability (≤19 ms2 were significantly associated with the EVENTs (hazard ratio 4.43, 95% confidence interval [CI] 1.35-14.54 and 5.41, 95% CI 1.87-15.65 respectively. EVENTs were also associated with other parameters, such as left ventricular ejection fraction, NYHA class, diuretic use, renal function, brain natriuretic peptide and hemoglobin level, left atrial size, left and right ventricular heart failure signs. After adjusting baroreflex sensitivity and low frequency power index for each of the abovementioned parameters, autonomic parameters were still significant predictors of hospitalization due to the heart failure decompensation.Simple, noninvasive autonomic indices can be helpful in identifying individuals with increased risk of hospitalization due to the heart failure decompensation among clinically stable patients with left ventricular systolic dysfunction, even when adjusted for other well-known clinical parameters.

Joint application of ground penetrating radar and electrical resistivity measurements for characterization of subsurface stratigraphy in Southwestern Nigeria

International Nuclear Information System (INIS)

Adepelumi, A A; Fayemi, O

2012-01-01

The frequent building collapses in Nigeria have been attributed to a lack of pre-construction investigations, which assist engineers in obtaining in situ geotechnical information. Further, the structural subsurface settings are often ignored or investigation is haphazardly carried out. To address this issue and demonstrate the importance of such a survey, a combination of ground penetrating radar (GPR) and vertical electrical sounding (VES) data were acquired in a part of Southwestern Nigeria. A 200 MHz antenna was used for the data acquisition along four traverses. The data were subjected to standard GPR processing techniques, and attribute analysis such as instantaneous frequency, amplitude and phase. Also, for comparative and engineering characterization purposes, longitudinal conductance and coefficient of anisotropy were computed from the VES results and used for determining the competency of the bedrocks. From the GPR results, it was observed that the mapped subsurface is characterized as erosional truncated at a low angle, which is southerly dipping and includes tangential reflections. Further, stratified rocks dipping at an angle of 32° occur between 1.0 and 4.5 m depth in all of the GPR sections; these strata were truncated by topsoil at shallow depths. Also, some of the sections depict ancient channel structures that have a dimension of 70 m × 40 m. The resistivity data suggest that the study area is characterized by four distinct geoelectric sequences. These comprise topsoil which is composed of clay-like sand to lateritic clay whose thickness ranges between 0.25 and 8.12 m, weathered bedrock with a thickness between 3.84 and 12.61 m, stratified bedrock with a thickness between 0.33 and 7.51 m, and fresh bedrock. These results reveal a complex subsurface geology and this characterizes the study area. The area has low to moderate longitudinal conductance and coefficient of anisotropy values, which suggest that incompetent to semi-competent bedrock

The New Left in the European Democracies: The Case of the German Radical Left

Directory of Open Access Journals (Sweden)

Marco Damiani

2015-03-01

Full Text Available The new form of the social and political conflict cannot be explained by the traditional categories of right and left, but it articulates to them on two plans, that of the establishment, intended like plan of the structured political conflict from the traditional actors, and that of the anti-establishment, in which new representations of politics emerge. The New Left is characterized by type of intermittent participation and new perspectives on mobilization inside the parties and the social movements. This type of parties differs moreover from the traditional ones left of the socialist and social democratic left in not arranging of organizations collaterals placed under the direction of the leadership of the same party. The mobilization that spontaneously assumes not conventional forms of active participation of the citizens, or is primed by the action of an associative network of which the same parties take part, than however does not monopo-lize the collective action. In this regard, the attention will be dedicated to the study of Die Linke: an anti-establishment party of the non-socialist German left-wing, heir to the communist tradition. The choice was affected to the German model because: 1 Germany is a country with a strong social democratic tradition, but 25 years after the fall of the Berlin Wall the German political system identifies a new antagonist political party; 2 Die Linke represents an interesting case in the political landscape of the European radical left because is a one-party that gives up at the federation of parties to try to unify the political parties of German radical left-wing.

Glycoprotein gene truncation in avian metapneumovirus subtype C isolates from the United States.

Science.gov (United States)

Velayudhan, Binu T; Yu, Qingzhong; Estevez, Carlos N; Nagaraja, Kakambi V; Halvorson, David A

2008-10-01

The length of the published glycoprotein (G) gene sequences of avian metapneumovirus subtype-C (aMPV-C) isolated from domestic turkeys and wild birds in the United States (1996-2003) remains controversial. To explore the G gene size variation in aMPV-C by the year of isolation and cell culture passage levels, we examined 21 turkey isolates of aMPV-C at different cell culture passages. The early domestic turkey isolates of aMPV-C (aMPV/CO/1996, aMPV/MN/1a-b, and 2a-b/97) had a G gene of 1,798 nucleotides (nt) that coded for a predicted protein of 585 amino acids (aa) and showed >97% nt similarity with that of aMPV-C isolated from Canada geese. This large G gene got truncated upon serial passages in Vero cell cultures by deletion of 1,015 nt near the end of the open reading frame. The recent domestic turkey isolates of aMPV-C lacked the large G gene but instead had a small G gene of 783 nt, irrespective of cell culture passage levels. In some cultures, both large and small genes were detected, indicating the existence of a mixed population of the virus. Apparently, serial passage of aMPV-C in cell cultures and natural passage in turkeys in the field led to truncation of the G gene, which may be a mechanism of virus evolution for survival in a new host or environment.

What is Beyond Right/Left?

DEFF Research Database (Denmark)

Dyrberg, Torben Bech

2009-01-01

The article looks at New Labour's move beyond right/left in the mid/late 1990s, which is an occasion to spell out the nature of right/left and what it means for democracy. In contrast to both defenders and critics of this move I argue in the first part that right/left is not an empty label bound up...... with the cleavage-lines of industrial society, but that it is an orientational metaphor which is articulated with others-in/out, up/down and front/back-and that we are in the process of moving beyond the industrial society right/left prototype. The second part looks at where New Labour is heading when moving beyond...... right/left. I argue that the new hegemonic orientation is that of front/back, which designs political renewal as a response to the social changes cutting across the outdated lines of contestation of partisan politics. The democratic problem of this move lies in squeezing politics between technocratic...

An improved method for purification of recombinant truncated heme oxygenase-1 by expanded bed adsorption and gel filtration.

Science.gov (United States)

Hu, Hong-Bo; Wang, Wei; Han, Ling; Zhou, Wen-Pu; Zhang, Xue-Hong

2007-03-01

Recombinant truncated human heme oxygenase-1 (hHO-1) expressed in Escherichia coli was efficiently separated and purified from feedstock by DEAE-ion exchange expanded bed adsorption. Protocol optimization of hHO-1 on DEAE adsorbent resulted in adsorption in 0 M NaCl and elution in 150 mM NaCl at a pH of 8.5. The active enzyme fractions separated from the expanded bed column were further purified by a Superdex 75 gel filtration step. The specific hHO-1 activity increased from 0.82 +/- 0.05 to 24.8 +/- 1.8 U/mg during the whole purification steps. The recovery and purification factor of truncated hHO-1 of the whole purification were 72.7 +/- 4.7 and 30.2 +/- 2.3%, respectively. This purification process can decrease the demand on the preparation of feedstock and simplify the purification process.

Human truncated thioredoxin (Trx80) as a novel mitogenic cytokine for white blood cells

OpenAIRE

Pekkari, Klas

2001-01-01

Thioredoxin (Trx) is a 12 kDa protein present in all species with a well-conserved active site sequence comprising -Cys-Gly-Pro-Cys-, which catalyzes oxido-reductase reactions. Trx regulates the activity of transcription factors and intracellular signalling pathways, and secreted Trx is a co-cytokine with several interleukins. In addition to full-length Trx a 10 kDa C-terminally truncated form of the protein is produced mainly by monocytes. This protein has unique eosinophil...

Non-alcoholic fatty liver disease is associated with left ventricular diastolic dysfunction in essential hypertension.

Science.gov (United States)

Fallo, F; Dalla Pozza, A; Sonino, N; Lupia, M; Tona, F; Federspil, G; Ermani, M; Catena, C; Soardo, G; Di Piazza, L; Bernardi, S; Bertolotto, M; Pinamonti, B; Fabris, B; Sechi, L A

2009-11-01

Insulin resistance is recognized as the pathophysiological hallmark of non-alcoholic fatty liver disease (NAFLD). A relation between insulin sensitivity and left ventricular morphology and function has been reported in essential hypertension, where a high prevalence of NAFLD has been recently found. We investigated the inter-relationship between left ventricular morphology/function, metabolic parameters and NAFLD in 86 never-treated essential hypertensive patients subdivided in two subgroups according to the presence (n = 48) or absence (n = 38) of NAFLD at ultrasonography. The two groups were similar as to sex, age and blood pressure levels. No patient had diabetes mellitus, obesity, hyperlipidemia, or other risk factors for liver disease. Body mass index, waist circumference, triglycerides, glucose, insulin, homeostasis model of assessment index for insulin resistance (HOMA-IR), aspartate aminotransferase and alanine aminotransferase were higher and adiponectin levels were lower in patients with NAFLD than in patients without NAFLD, and were associated with NAFLD at univariate analysis. Patients with NAFLD had similar prevalence of left ventricular hypertrophy compared to patients without NAFLD, but a higher prevalence of diastolic dysfunction (62.5 vs 21.1%, P 220 ms. Diastolic dysfunction (P = 0.040) and HOMA-IR (P = 0.012) remained independently associated with NAFLD at backward multivariate analysis. Non-alcoholic fatty liver disease was associated with insulin resistance and abnormalities of left ventricular diastolic function in a cohort of patients with essential hypertension, suggesting a concomitant increase of metabolic and cardiac risk in this condition.

Evaluation of the truncated perturbed chain-polar statistical associating fluid theory for complex mixture fluid phase equilibria

DEFF Research Database (Denmark)

Karakatsani, Eirini; Kontogeorgis, Georgios; Economou, Ioannis

2006-01-01

Perturbed chain-statistical associating fluid theory (PC-SAFT) was extended rigorously to polar fluids based on the theory of Stell and co-workers [Mol. Phys. 1977, 33, 987]. The new PC-PSAFT was simplified to truncated PC-PSAFT (tPC-PSAFT) so that it can be practical for real polar fluid...

Sharpening Sharpe Ratios

OpenAIRE

William N. Goetzmann; Jonathan E. Ingersoll Jr.; Matthew I. Spiegel; Ivo Welch

2002-01-01

It is now well known that the Sharpe ratio and other related reward-to-risk measures may be manipulated with option-like strategies. In this paper we derive the general conditions for achieving the maximum expected Sharpe ratio. We derive static rules for achieving the maximum Sharpe ratio with two or more options, as well as a continuum of derivative contracts. The optimal strategy has a truncated right tail and a fat left tail. We also derive dynamic rules for increasing the Sharpe ratio. O...

Weakly nonlinear sloshing in a truncated circular conical tank

International Nuclear Information System (INIS)

Gavrilyuk, I P; Hermann, M; Lukovsky, I A; Solodun, O V; Timokha, A N

2013-01-01

Sloshing of an ideal incompressible liquid in a rigid truncated (tapered) conical tank is considered when the tank performs small-magnitude oscillatory motions with the forcing frequency close to the lowest natural sloshing frequency. The multimodal method, the non-conformal mapping technique and the Moiseev type asymptotics are employed to derive a finite-dimensional system of weakly nonlinear ordinary differential (modal) equations. This modal system is a generalization of that by Gavrilyuk et al 2005 Fluid Dyn. Res. 37 399–429. Using the derived modal equations, we classify the resonant steady-state wave regimes occurring due to horizontal harmonic tank excitations. The frequency ranges are detected where the ‘planar’ and/or ‘swirling’ steady-state sloshing are stable as well as a range in which all steady-state wave regimes are not stable and irregular (chaotic) liquid motions occur is established. The results on the frequency ranges are qualitatively supported by experiments by Matta E 2002 PhD Thesis Politecnico di Torino, Torino. (paper)

Administering truncated receive functions in a parallel messaging interface

Science.gov (United States)