Limited data tomographic image reconstruction via dual formulation of total variation minimization

NASA Astrophysics Data System (ADS)

Jang, Kwang Eun; Sung, Younghun; Lee, Kangeui; Lee, Jongha; Cho, Seungryong

2011-03-01

The X-ray mammography is the primary imaging modality for breast cancer screening. For the dense breast, however, the mammogram is usually difficult to read due to tissue overlap problem caused by the superposition of normal tissues. The digital breast tomosynthesis (DBT) that measures several low dose projections over a limited angle range may be an alternative modality for breast imaging, since it allows the visualization of the cross-sectional information of breast. The DBT, however, may suffer from the aliasing artifact and the severe noise corruption. To overcome these problems, a total variation (TV) regularized statistical reconstruction algorithm is presented. Inspired by the dual formulation of TV minimization in denoising and deblurring problems, we derived a gradient-type algorithm based on statistical model of X-ray tomography. The objective function is comprised of a data fidelity term derived from the statistical model and a TV regularization term. The gradient of the objective function can be easily calculated using simple operations in terms of auxiliary variables. After a descending step, the data fidelity term is renewed in each iteration. Since the proposed algorithm can be implemented without sophisticated operations such as matrix inverse, it provides an efficient way to include the TV regularization in the statistical reconstruction method, which results in a fast and robust estimation for low dose projections over the limited angle range. Initial tests with an experimental DBT system confirmed our finding.

Penalized weighted least-squares approach for multienergy computed tomography image reconstruction via structure tensor total variation regularization.

PubMed

Zeng, Dong; Gao, Yuanyuan; Huang, Jing; Bian, Zhaoying; Zhang, Hua; Lu, Lijun; Ma, Jianhua

2016-10-01

Multienergy computed tomography (MECT) allows identifying and differentiating different materials through simultaneous capture of multiple sets of energy-selective data belonging to specific energy windows. However, because sufficient photon counts are not available in each energy window compared with that in the whole energy window, the MECT images reconstructed by the analytical approach often suffer from poor signal-to-noise and strong streak artifacts. To address the particular challenge, this work presents a penalized weighted least-squares (PWLS) scheme by incorporating the new concept of structure tensor total variation (STV) regularization, which is henceforth referred to as 'PWLS-STV' for simplicity. Specifically, the STV regularization is derived by penalizing higher-order derivatives of the desired MECT images. Thus it could provide more robust measures of image variation, which can eliminate the patchy artifacts often observed in total variation (TV) regularization. Subsequently, an alternating optimization algorithm was adopted to minimize the objective function. Extensive experiments with a digital XCAT phantom and meat specimen clearly demonstrate that the present PWLS-STV algorithm can achieve more gains than the existing TV-based algorithms and the conventional filtered backpeojection (FBP) algorithm in terms of both quantitative and visual quality evaluations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Novel Fourier-based iterative reconstruction for sparse fan projection using alternating direction total variation minimization

NASA Astrophysics Data System (ADS)

Zhao, Jin; Han-Ming, Zhang; Bin, Yan; Lei, Li; Lin-Yuan, Wang; Ai-Long, Cai

2016-03-01

Sparse-view x-ray computed tomography (CT) imaging is an interesting topic in CT field and can efficiently decrease radiation dose. Compared with spatial reconstruction, a Fourier-based algorithm has advantages in reconstruction speed and memory usage. A novel Fourier-based iterative reconstruction technique that utilizes non-uniform fast Fourier transform (NUFFT) is presented in this work along with advanced total variation (TV) regularization for a fan sparse-view CT. The proposition of a selective matrix contributes to improve reconstruction quality. The new method employs the NUFFT and its adjoin to iterate back and forth between the Fourier and image space. The performance of the proposed algorithm is demonstrated through a series of digital simulations and experimental phantom studies. Results of the proposed algorithm are compared with those of existing TV-regularized techniques based on compressed sensing method, as well as basic algebraic reconstruction technique. Compared with the existing TV-regularized techniques, the proposed Fourier-based technique significantly improves convergence rate and reduces memory allocation, respectively. Projected supported by the National High Technology Research and Development Program of China (Grant No. 2012AA011603) and the National Natural Science Foundation of China (Grant No. 61372172).

47 CFR 76.614 - Cable television system regular monitoring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false Cable television system regular monitoring. 76... system regular monitoring. Cable television operators transmitting carriers in the frequency bands 108-137 and 225-400 MHz shall provide for a program of regular monitoring for signal leakage by...

47 CFR 76.614 - Cable television system regular monitoring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false Cable television system regular monitoring. 76... system regular monitoring. Cable television operators transmitting carriers in the frequency bands 108-137 and 225-400 MHz shall provide for a program of regular monitoring for signal leakage by...

47 CFR 76.614 - Cable television system regular monitoring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Cable television system regular monitoring. 76... system regular monitoring. Cable television operators transmitting carriers in the frequency bands 108-137 and 225-400 MHz shall provide for a program of regular monitoring for signal leakage by...

Nonsmooth, nonconvex regularizers applied to linear electromagnetic inverse problems

NASA Astrophysics Data System (ADS)

Hidalgo-Silva, H.; Gomez-Trevino, E.

2017-12-01

Tikhonov's regularization method is the standard technique applied to obtain models of the subsurface conductivity distribution from electric or electromagnetic measurements by solving UT (m) = | F (m) - d |2 + λ P(m). The second term correspond to the stabilizing functional, with P (m) = | ∇ m |2 the usual approach, and λ the regularization parameter. Due to the roughness penalizer inclusion, the model developed by Tikhonov's algorithm tends to smear discontinuities, a feature that may be undesirable. An important requirement for the regularizer is to allow the recovery of edges, and smooth the homogeneous parts. As is well known, Total Variation (TV) is now the standard approach to meet this requirement. Recently, Wang et.al. proved convergence for alternating direction method of multipliers in nonconvex, nonsmooth optimization. In this work we present a study of several algorithms for model recovering of Geosounding data based on Infimal Convolution, and also on hybrid, TV and second order TV and nonsmooth, nonconvex regularizers, observing their performance on synthetic and real data. The algorithms are based on Bregman iteration and Split Bregman method, and the geosounding method is the low-induction numbers magnetic dipoles. Non-smooth regularizers are considered using the Legendre-Fenchel transform.

TU-CD-BRA-12: Coupling PET Image Restoration and Segmentation Using Variational Method with Multiple Regularizations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, L; Tan, S; Lu, W

Purpose: To propose a new variational method which couples image restoration with tumor segmentation for PET images using multiple regularizations. Methods: Partial volume effect (PVE) is a major degrading factor impacting tumor segmentation accuracy in PET imaging. The existing segmentation methods usually need to take prior calibrations to compensate PVE and they are highly system-dependent. Taking into account that image restoration and segmentation can promote each other and they are tightly coupled, we proposed a variational method to solve the two problems together. Our method integrated total variation (TV) semi-blind deconvolution and Mumford-Shah (MS) segmentation. The TV norm was usedmore » on edges to protect the edge information, and the L{sub 2} norm was used to avoid staircase effect in the no-edge area. The blur kernel was constrained to the Gaussian model parameterized by its variance and we assumed that the variances in the X-Y and Z directions are different. The energy functional was iteratively optimized by an alternate minimization algorithm. Segmentation performance was tested on eleven patients with non-Hodgkin’s lymphoma, and evaluated by Dice similarity index (DSI) and classification error (CE). For comparison, seven other widely used methods were also tested and evaluated. Results: The combination of TV and L{sub 2} regularizations effectively improved the segmentation accuracy. The average DSI increased by around 0.1 than using either the TV or the L{sub 2} norm. The proposed method was obviously superior to other tested methods. It has an average DSI and CE of 0.80 and 0.41, while the FCM method — the second best one — has only an average DSI and CE of 0.66 and 0.64. Conclusion: Coupling image restoration and segmentation can handle PVE and thus improves tumor segmentation accuracy in PET. Alternate use of TV and L2 regularizations can further improve the performance of the algorithm. This work was supported in part by National Natural Science Foundation of China (NNSFC), under Grant No.61375018, and Fundamental Research Funds for the Central Universities, under Grant No. 2012QN086. Wei Lu was supported in part by the National Institutes of Health (NIH) Grant No. R01 CA172638.« less

Image superresolution by midfrequency sparse representation and total variation regularization

NASA Astrophysics Data System (ADS)

Xu, Jian; Chang, Zhiguo; Fan, Jiulun; Zhao, Xiaoqiang; Wu, Xiaomin; Wang, Yanzi

2015-01-01

Machine learning has provided many good tools for superresolution, whereas existing methods still need to be improved in many aspects. On one hand, the memory and time cost should be reduced. On the other hand, the step edges of the results obtained by the existing methods are not clear enough. We do the following work. First, we propose a method to extract the midfrequency features for dictionary learning. This method brings the benefit of a reduction of the memory and time complexity without sacrificing the performance. Second, we propose a detailed wiping-off total variation (DWO-TV) regularization model to reconstruct the sharp step edges. This model adds a novel constraint on the downsampling version of the high-resolution image to wipe off the details and artifacts and sharpen the step edges. Finally, step edges produced by the DWO-TV regularization and the details provided by learning are fused. Experimental results show that the proposed method offers a desirable compromise between low time and memory cost and the reconstruction quality.

Total variation-based method for radar coincidence imaging with model mismatch for extended target

NASA Astrophysics Data System (ADS)

Cao, Kaicheng; Zhou, Xiaoli; Cheng, Yongqiang; Fan, Bo; Qin, Yuliang

2017-11-01

Originating from traditional optical coincidence imaging, radar coincidence imaging (RCI) is a staring/forward-looking imaging technique. In RCI, the reference matrix must be computed precisely to reconstruct the image as preferred; unfortunately, such precision is almost impossible due to the existence of model mismatch in practical applications. Although some conventional sparse recovery algorithms are proposed to solve the model-mismatch problem, they are inapplicable to nonsparse targets. We therefore sought to derive the signal model of RCI with model mismatch by replacing the sparsity constraint item with total variation (TV) regularization in the sparse total least squares optimization problem; in this manner, we obtain the objective function of RCI with model mismatch for an extended target. A more robust and efficient algorithm called TV-TLS is proposed, in which the objective function is divided into two parts and the perturbation matrix and scattering coefficients are updated alternately. Moreover, due to the ability of TV regularization to recover sparse signal or image with sparse gradient, TV-TLS method is also applicable to sparse recovering. Results of numerical experiments demonstrate that, for uniform extended targets, sparse targets, and real extended targets, the algorithm can achieve preferred imaging performance both in suppressing noise and in adapting to model mismatch.

Parallel algorithm of real-time infrared image restoration based on total variation theory

NASA Astrophysics Data System (ADS)

Zhu, Ran; Li, Miao; Long, Yunli; Zeng, Yaoyuan; An, Wei

2015-10-01

Image restoration is a necessary preprocessing step for infrared remote sensing applications. Traditional methods allow us to remove the noise but penalize too much the gradients corresponding to edges. Image restoration techniques based on variational approaches can solve this over-smoothing problem for the merits of their well-defined mathematical modeling of the restore procedure. The total variation (TV) of infrared image is introduced as a L1 regularization term added to the objective energy functional. It converts the restoration process to an optimization problem of functional involving a fidelity term to the image data plus a regularization term. Infrared image restoration technology with TV-L1 model exploits the remote sensing data obtained sufficiently and preserves information at edges caused by clouds. Numerical implementation algorithm is presented in detail. Analysis indicates that the structure of this algorithm can be easily implemented in parallelization. Therefore a parallel implementation of the TV-L1 filter based on multicore architecture with shared memory is proposed for infrared real-time remote sensing systems. Massive computation of image data is performed in parallel by cooperating threads running simultaneously on multiple cores. Several groups of synthetic infrared image data are used to validate the feasibility and effectiveness of the proposed parallel algorithm. Quantitative analysis of measuring the restored image quality compared to input image is presented. Experiment results show that the TV-L1 filter can restore the varying background image reasonably, and that its performance can achieve the requirement of real-time image processing.

Mixed Gaussian-Impulse Noise Image Restoration Via Total Variation

DTIC Science & Technology

2012-05-01

deblurring under impulse noise ,” J. Math. Imaging Vis., vol. 36, pp. 46–53, January 2010. [5] B. Li, Q. Liu, J. Xu, and X. Luo, “A new method for removing......Several Total Variation (TV) regularization methods have recently been proposed to address denoising under mixed Gaussian and impulse noise . While

47 CFR 76.614 - Cable television system regular monitoring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Cable television system regular monitoring. 76.614 Section 76.614 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.614 Cable television...

Compressed sensing with gradient total variation for low-dose CBCT reconstruction

NASA Astrophysics Data System (ADS)

Seo, Chang-Woo; Cha, Bo Kyung; Jeon, Seongchae; Huh, Young; Park, Justin C.; Lee, Byeonghun; Baek, Junghee; Kim, Eunyoung

2015-06-01

This paper describes the improvement of convergence speed with gradient total variation (GTV) in compressed sensing (CS) for low-dose cone-beam computed tomography (CBCT) reconstruction. We derive a fast algorithm for the constrained total variation (TV)-based a minimum number of noisy projections. To achieve this task we combine the GTV with a TV-norm regularization term to promote an accelerated sparsity in the X-ray attenuation characteristics of the human body. The GTV is derived from a TV and enforces more efficient computationally and faster in convergence until a desired solution is achieved. The numerical algorithm is simple and derives relatively fast convergence. We apply a gradient projection algorithm that seeks a solution iteratively in the direction of the projected gradient while enforcing a non-negatively of the found solution. In comparison with the Feldkamp, Davis, and Kress (FDK) and conventional TV algorithms, the proposed GTV algorithm showed convergence in ≤18 iterations, whereas the original TV algorithm needs at least 34 iterations in reducing 50% of the projections compared with the FDK algorithm in order to reconstruct the chest phantom images. Future investigation includes improving imaging quality, particularly regarding X-ray cone-beam scatter, and motion artifacts of CBCT reconstruction.

GPU-accelerated regularized iterative reconstruction for few-view cone beam CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matenine, Dmitri, E-mail: dmitri.matenine.1@ulaval.ca; Goussard, Yves, E-mail: yves.goussard@polymtl.ca; Després, Philippe, E-mail: philippe.despres@phy.ulaval.ca

2015-04-15

Purpose: The present work proposes an iterative reconstruction technique designed for x-ray transmission computed tomography (CT). The main objective is to provide a model-based solution to the cone-beam CT reconstruction problem, yielding accurate low-dose images via few-views acquisitions in clinically acceptable time frames. Methods: The proposed technique combines a modified ordered subsets convex (OSC) algorithm and the total variation minimization (TV) regularization technique and is called OSC-TV. The number of subsets of each OSC iteration follows a reduction pattern in order to ensure the best performance of the regularization method. Considering the high computational cost of the algorithm, it ismore » implemented on a graphics processing unit, using parallelization to accelerate computations. Results: The reconstructions were performed on computer-simulated as well as human pelvic cone-beam CT projection data and image quality was assessed. In terms of convergence and image quality, OSC-TV performs well in reconstruction of low-dose cone-beam CT data obtained via a few-view acquisition protocol. It compares favorably to the few-view TV-regularized projections onto convex sets (POCS-TV) algorithm. It also appears to be a viable alternative to full-dataset filtered backprojection. Execution times are of 1–2 min and are compatible with the typical clinical workflow for nonreal-time applications. Conclusions: Considering the image quality and execution times, this method may be useful for reconstruction of low-dose clinical acquisitions. It may be of particular benefit to patients who undergo multiple acquisitions by reducing the overall imaging radiation dose and associated risks.« less

Accurate low-dose iterative CT reconstruction from few projections by Generalized Anisotropic Total Variation minimization for industrial CT.

PubMed

Debatin, Maurice; Hesser, Jürgen

2015-01-01

Reducing the amount of time for data acquisition and reconstruction in industrial CT decreases the operation time of the X-ray machine and therefore increases the sales. This can be achieved by reducing both, the dose and the pulse length of the CT system and the number of projections for the reconstruction, respectively. In this paper, a novel generalized Anisotropic Total Variation regularization for under-sampled, low-dose iterative CT reconstruction is discussed and compared to the standard methods, Total Variation, Adaptive weighted Total Variation and Filtered Backprojection. The novel regularization function uses a priori information about the Gradient Magnitude Distribution of the scanned object for the reconstruction. We provide a general parameterization scheme and evaluate the efficiency of our new algorithm for different noise levels and different number of projection views. When noise is not present, error-free reconstructions are achievable for AwTV and GATV from 40 projections. In cases where noise is simulated, our strategy achieves a Relative Root Mean Square Error that is up to 11 times lower than Total Variation-based and up to 4 times lower than AwTV-based iterative statistical reconstruction (e.g. for a SNR of 223 and 40 projections). To obtain the same reconstruction quality as achieved by Total Variation, the projection number and the pulse length, and the acquisition time and the dose respectively can be reduced by a factor of approximately 3.5, when AwTV is used and a factor of approximately 6.7, when our proposed algorithm is used.

Computerized tomography with total variation and with shearlets

NASA Astrophysics Data System (ADS)

Garduño, Edgar; Herman, Gabor T.

2017-04-01

To reduce the x-ray dose in computerized tomography (CT), many constrained optimization approaches have been proposed aiming at minimizing a regularizing function that measures a lack of consistency with some prior knowledge about the object that is being imaged, subject to a (predetermined) level of consistency with the detected attenuation of x-rays. One commonly investigated regularizing function is total variation (TV), while other publications advocate the use of some type of multiscale geometric transform in the definition of the regularizing function, a particular recent choice for this is the shearlet transform. Proponents of the shearlet transform in the regularizing function claim that the reconstructions so obtained are better than those produced using TV for texture preservation (but may be worse for noise reduction). In this paper we report results related to this claim. In our reported experiments using simulated CT data collection of the head, reconstructions whose shearlet transform has a small ℓ 1-norm are not more efficacious than reconstructions that have a small TV value. Our experiments for making such comparisons use the recently-developed superiorization methodology for both regularizing functions. Superiorization is an automated procedure for turning an iterative algorithm for producing images that satisfy a primary criterion (such as consistency with the observed measurements) into its superiorized version that will produce results that, according to the primary criterion are as good as those produced by the original algorithm, but in addition are superior to them according to a secondary (regularizing) criterion. The method presented for superiorization involving the ℓ 1-norm of the shearlet transform is novel and is quite general: It can be used for any regularizing function that is defined as the ℓ 1-norm of a transform specified by the application of a matrix. Because in the previous literature the split Bregman algorithm is used for similar purposes, a section is included comparing the results of the superiorization algorithm with the split Bregman algorithm.

Total variation superiorized conjugate gradient method for image reconstruction

NASA Astrophysics Data System (ADS)

Zibetti, Marcelo V. W.; Lin, Chuan; Herman, Gabor T.

2018-03-01

The conjugate gradient (CG) method is commonly used for the relatively-rapid solution of least squares problems. In image reconstruction, the problem can be ill-posed and also contaminated by noise; due to this, approaches such as regularization should be utilized. Total variation (TV) is a useful regularization penalty, frequently utilized in image reconstruction for generating images with sharp edges. When a non-quadratic norm is selected for regularization, as is the case for TV, then it is no longer possible to use CG. Non-linear CG is an alternative, but it does not share the efficiency that CG shows with least squares and methods such as fast iterative shrinkage-thresholding algorithms (FISTA) are preferred for problems with TV norm. A different approach to including prior information is superiorization. In this paper it is shown that the conjugate gradient method can be superiorized. Five different CG variants are proposed, including preconditioned CG. The CG methods superiorized by the total variation norm are presented and their performance in image reconstruction is demonstrated. It is illustrated that some of the proposed variants of the superiorized CG method can produce reconstructions of superior quality to those produced by FISTA and in less computational time, due to the speed of the original CG for least squares problems. In the Appendix we examine the behavior of one of the superiorized CG methods (we call it S-CG); one of its input parameters is a positive number ɛ. It is proved that, for any given ɛ that is greater than the half-squared-residual for the least squares solution, S-CG terminates in a finite number of steps with an output for which the half-squared-residual is less than or equal to ɛ. Importantly, it is also the case that the output will have a lower value of TV than what would be provided by unsuperiorized CG for the same value ɛ of the half-squared residual.

Low dose CBCT reconstruction via prior contour based total variation (PCTV) regularization: a feasibility study

NASA Astrophysics Data System (ADS)

Chen, Yingxuan; Yin, Fang-Fang; Zhang, Yawei; Zhang, You; Ren, Lei

2018-04-01

Purpose: compressed sensing reconstruction using total variation (TV) tends to over-smooth the edge information by uniformly penalizing the image gradient. The goal of this study is to develop a novel prior contour based TV (PCTV) method to enhance the edge information in compressed sensing reconstruction for CBCT. Methods: the edge information is extracted from prior planning-CT via edge detection. Prior CT is first registered with on-board CBCT reconstructed with TV method through rigid or deformable registration. The edge contours in prior-CT is then mapped to CBCT and used as the weight map for TV regularization to enhance edge information in CBCT reconstruction. The PCTV method was evaluated using extended-cardiac-torso (XCAT) phantom, physical CatPhan phantom and brain patient data. Results were compared with both TV and edge preserving TV (EPTV) methods which are commonly used for limited projection CBCT reconstruction. Relative error was used to calculate pixel value difference and edge cross correlation was defined as the similarity of edge information between reconstructed images and ground truth in the quantitative evaluation. Results: compared to TV and EPTV, PCTV enhanced the edge information of bone, lung vessels and tumor in XCAT reconstruction and complex bony structures in brain patient CBCT. In XCAT study using 45 half-fan CBCT projections, compared with ground truth, relative errors were 1.5%, 0.7% and 0.3% and edge cross correlations were 0.66, 0.72 and 0.78 for TV, EPTV and PCTV, respectively. PCTV is more robust to the projection number reduction. Edge enhancement was reduced slightly with noisy projections but PCTV was still superior to other methods. PCTV can maintain resolution while reducing the noise in the low mAs CatPhan reconstruction. Low contrast edges were preserved better with PCTV compared with TV and EPTV. Conclusion: PCTV preserved edge information as well as reduced streak artifacts and noise in low dose CBCT reconstruction. PCTV is superior to TV and EPTV methods in edge enhancement, which can potentially improve the localization accuracy in radiation therapy.

A Description of Similarity of Personality between Selected Groups of Television Viewers and Certain Television Roles Regularly Viewed by Them.

ERIC Educational Resources Information Center

Perrow, Maxwell Vermilyea

The aim of this study was to provide quantitative measurement of the degree of identification, or lack of identification, that takes place between the viewers of television and the television roles they like and view regularly and those they dislike and view infrequently. Participants in the study were asked to keep a Television Viewing Diary and…

SparseBeads data: benchmarking sparsity-regularized computed tomography

NASA Astrophysics Data System (ADS)

Jørgensen, Jakob S.; Coban, Sophia B.; Lionheart, William R. B.; McDonald, Samuel A.; Withers, Philip J.

2017-12-01

Sparsity regularization (SR) such as total variation (TV) minimization allows accurate image reconstruction in x-ray computed tomography (CT) from fewer projections than analytical methods. Exactly how few projections suffice and how this number may depend on the image remain poorly understood. Compressive sensing connects the critical number of projections to the image sparsity, but does not cover CT, however empirical results suggest a similar connection. The present work establishes for real CT data a connection between gradient sparsity and the sufficient number of projections for accurate TV-regularized reconstruction. A collection of 48 x-ray CT datasets called SparseBeads was designed for benchmarking SR reconstruction algorithms. Beadpacks comprising glass beads of five different sizes as well as mixtures were scanned in a micro-CT scanner to provide structured datasets with variable image sparsity levels, number of projections and noise levels to allow the systematic assessment of parameters affecting performance of SR reconstruction algorithms6. Using the SparseBeads data, TV-regularized reconstruction quality was assessed as a function of numbers of projections and gradient sparsity. The critical number of projections for satisfactory TV-regularized reconstruction increased almost linearly with the gradient sparsity. This establishes a quantitative guideline from which one may predict how few projections to acquire based on expected sample sparsity level as an aid in planning of dose- or time-critical experiments. The results are expected to hold for samples of similar characteristics, i.e. consisting of few, distinct phases with relatively simple structure. Such cases are plentiful in porous media, composite materials, foams, as well as non-destructive testing and metrology. For samples of other characteristics the proposed methodology may be used to investigate similar relations.

Parameter selection in limited data cone-beam CT reconstruction using edge-preserving total variation algorithms

NASA Astrophysics Data System (ADS)

Lohvithee, Manasavee; Biguri, Ander; Soleimani, Manuchehr

2017-12-01

There are a number of powerful total variation (TV) regularization methods that have great promise in limited data cone-beam CT reconstruction with an enhancement of image quality. These promising TV methods require careful selection of the image reconstruction parameters, for which there are no well-established criteria. This paper presents a comprehensive evaluation of parameter selection in a number of major TV-based reconstruction algorithms. An appropriate way of selecting the values for each individual parameter has been suggested. Finally, a new adaptive-weighted projection-controlled steepest descent (AwPCSD) algorithm is presented, which implements the edge-preserving function for CBCT reconstruction with limited data. The proposed algorithm shows significant robustness compared to three other existing algorithms: ASD-POCS, AwASD-POCS and PCSD. The proposed AwPCSD algorithm is able to preserve the edges of the reconstructed images better with fewer sensitive parameters to tune.

Total-variation based velocity inversion with Bregmanized operator splitting algorithm

NASA Astrophysics Data System (ADS)

Zand, Toktam; Gholami, Ali

2018-04-01

Many problems in applied geophysics can be formulated as a linear inverse problem. The associated problems, however, are large-scale and ill-conditioned. Therefore, regularization techniques are needed to be employed for solving them and generating a stable and acceptable solution. We consider numerical methods for solving such problems in this paper. In order to tackle the ill-conditioning of the problem we use blockiness as a prior information of the subsurface parameters and formulate the problem as a constrained total variation (TV) regularization. The Bregmanized operator splitting (BOS) algorithm as a combination of the Bregman iteration and the proximal forward backward operator splitting method is developed to solve the arranged problem. Two main advantages of this new algorithm are that no matrix inversion is required and that a discrepancy stopping criterion is used to stop the iterations, which allow efficient solution of large-scale problems. The high performance of the proposed TV regularization method is demonstrated using two different experiments: 1) velocity inversion from (synthetic) seismic data which is based on Born approximation, 2) computing interval velocities from RMS velocities via Dix formula. Numerical examples are presented to verify the feasibility of the proposed method for high-resolution velocity inversion.

Preconditioned Alternating Projection Algorithms for Maximum a Posteriori ECT Reconstruction

PubMed Central

Krol, Andrzej; Li, Si; Shen, Lixin; Xu, Yuesheng

2012-01-01

We propose a preconditioned alternating projection algorithm (PAPA) for solving the maximum a posteriori (MAP) emission computed tomography (ECT) reconstruction problem. Specifically, we formulate the reconstruction problem as a constrained convex optimization problem with the total variation (TV) regularization. We then characterize the solution of the constrained convex optimization problem and show that it satisfies a system of fixed-point equations defined in terms of two proximity operators raised from the convex functions that define the TV-norm and the constrain involved in the problem. The characterization (of the solution) via the proximity operators that define two projection operators naturally leads to an alternating projection algorithm for finding the solution. For efficient numerical computation, we introduce to the alternating projection algorithm a preconditioning matrix (the EM-preconditioner) for the dense system matrix involved in the optimization problem. We prove theoretically convergence of the preconditioned alternating projection algorithm. In numerical experiments, performance of our algorithms, with an appropriately selected preconditioning matrix, is compared with performance of the conventional MAP expectation-maximization (MAP-EM) algorithm with TV regularizer (EM-TV) and that of the recently developed nested EM-TV algorithm for ECT reconstruction. Based on the numerical experiments performed in this work, we observe that the alternating projection algorithm with the EM-preconditioner outperforms significantly the EM-TV in all aspects including the convergence speed, the noise in the reconstructed images and the image quality. It also outperforms the nested EM-TV in the convergence speed while providing comparable image quality. PMID:23271835

Preconditioned alternating projection algorithms for maximum a posteriori ECT reconstruction

NASA Astrophysics Data System (ADS)

Krol, Andrzej; Li, Si; Shen, Lixin; Xu, Yuesheng

2012-11-01

We propose a preconditioned alternating projection algorithm (PAPA) for solving the maximum a posteriori (MAP) emission computed tomography (ECT) reconstruction problem. Specifically, we formulate the reconstruction problem as a constrained convex optimization problem with the total variation (TV) regularization. We then characterize the solution of the constrained convex optimization problem and show that it satisfies a system of fixed-point equations defined in terms of two proximity operators raised from the convex functions that define the TV-norm and the constraint involved in the problem. The characterization (of the solution) via the proximity operators that define two projection operators naturally leads to an alternating projection algorithm for finding the solution. For efficient numerical computation, we introduce to the alternating projection algorithm a preconditioning matrix (the EM-preconditioner) for the dense system matrix involved in the optimization problem. We prove theoretically convergence of the PAPA. In numerical experiments, performance of our algorithms, with an appropriately selected preconditioning matrix, is compared with performance of the conventional MAP expectation-maximization (MAP-EM) algorithm with TV regularizer (EM-TV) and that of the recently developed nested EM-TV algorithm for ECT reconstruction. Based on the numerical experiments performed in this work, we observe that the alternating projection algorithm with the EM-preconditioner outperforms significantly the EM-TV in all aspects including the convergence speed, the noise in the reconstructed images and the image quality. It also outperforms the nested EM-TV in the convergence speed while providing comparable image quality.

Median prior constrained TV algorithm for sparse view low-dose CT reconstruction.

PubMed

Liu, Yi; Shangguan, Hong; Zhang, Quan; Zhu, Hongqing; Shu, Huazhong; Gui, Zhiguo

2015-05-01

It is known that lowering the X-ray tube current (mAs) or tube voltage (kVp) and simultaneously reducing the total number of X-ray views (sparse view) is an effective means to achieve low-dose in computed tomography (CT) scan. However, the associated image quality by the conventional filtered back-projection (FBP) usually degrades due to the excessive quantum noise. Although sparse-view CT reconstruction algorithm via total variation (TV), in the scanning protocol of reducing X-ray tube current, has been demonstrated to be able to result in significant radiation dose reduction while maintain image quality, noticeable patchy artifacts still exist in reconstructed images. In this study, to address the problem of patchy artifacts, we proposed a median prior constrained TV regularization to retain the image quality by introducing an auxiliary vector m in register with the object. Specifically, the approximate action of m is to draw, in each iteration, an object voxel toward its own local median, aiming to improve low-dose image quality with sparse-view projection measurements. Subsequently, an alternating optimization algorithm is adopted to optimize the associative objective function. We refer to the median prior constrained TV regularization as "TV_MP" for simplicity. Experimental results on digital phantoms and clinical phantom demonstrated that the proposed TV_MP with appropriate control parameters can not only ensure a higher signal to noise ratio (SNR) of the reconstructed image, but also its resolution compared with the original TV method. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fractional-order TV-L2 model for image denoising

NASA Astrophysics Data System (ADS)

Chen, Dali; Sun, Shenshen; Zhang, Congrong; Chen, YangQuan; Xue, Dingyu

2013-10-01

This paper proposes a new fractional order total variation (TV) denoising method, which provides a much more elegant and effective way of treating problems of the algorithm implementation, ill-posed inverse, regularization parameter selection and blocky effect. Two fractional order TV-L2 models are constructed for image denoising. The majorization-minimization (MM) algorithm is used to decompose these two complex fractional TV optimization problems into a set of linear optimization problems which can be solved by the conjugate gradient algorithm. The final adaptive numerical procedure is given. Finally, we report experimental results which show that the proposed methodology avoids the blocky effect and achieves state-of-the-art performance. In addition, two medical image processing experiments are presented to demonstrate the validity of the proposed methodology.

Effective noise-suppressed and artifact-reduced reconstruction of SPECT data using a preconditioned alternating projection algorithm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Si; Xu, Yuesheng, E-mail: yxu06@syr.edu; Zhang, Jiahan

Purpose: The authors have recently developed a preconditioned alternating projection algorithm (PAPA) with total variation (TV) regularizer for solving the penalized-likelihood optimization model for single-photon emission computed tomography (SPECT) reconstruction. This algorithm belongs to a novel class of fixed-point proximity methods. The goal of this work is to investigate how PAPA performs while dealing with realistic noisy SPECT data, to compare its performance with more conventional methods, and to address issues with TV artifacts by proposing a novel form of the algorithm invoking high-order TV regularization, denoted as HOTV-PAPA, which has been explored and studied extensively in the present work.more » Methods: Using Monte Carlo methods, the authors simulate noisy SPECT data from two water cylinders; one contains lumpy “warm” background and “hot” lesions of various sizes with Gaussian activity distribution, and the other is a reference cylinder without hot lesions. The authors study the performance of HOTV-PAPA and compare it with PAPA using first-order TV regularization (TV-PAPA), the Panin–Zeng–Gullberg one-step-late method with TV regularization (TV-OSL), and an expectation–maximization algorithm with Gaussian postfilter (GPF-EM). The authors select penalty-weights (hyperparameters) by qualitatively balancing the trade-off between resolution and image noise separately for TV-PAPA and TV-OSL. However, the authors arrived at the same penalty-weight value for both of them. The authors set the first penalty-weight in HOTV-PAPA equal to the optimal penalty-weight found for TV-PAPA. The second penalty-weight needed for HOTV-PAPA is tuned by balancing resolution and the severity of staircase artifacts. The authors adjust the Gaussian postfilter to approximately match the local point spread function of GPF-EM and HOTV-PAPA. The authors examine hot lesion detectability, study local spatial resolution, analyze background noise properties, estimate mean square errors (MSEs), and report the convergence speed and computation time. Results: HOTV-PAPA yields the best signal-to-noise ratio, followed by TV-PAPA and TV-OSL/GPF-EM. The local spatial resolution of HOTV-PAPA is somewhat worse than that of TV-PAPA and TV-OSL. Images reconstructed using HOTV-PAPA have the lowest local noise power spectrum (LNPS) amplitudes, followed by TV-PAPA, TV-OSL, and GPF-EM. The LNPS peak of GPF-EM is shifted toward higher spatial frequencies than those for the three other methods. The PAPA-type methods exhibit much lower ensemble noise, ensemble voxel variance, and image roughness. HOTV-PAPA performs best in these categories. Whereas images reconstructed using both TV-PAPA and TV-OSL are degraded by severe staircase artifacts; HOTV-PAPA substantially reduces such artifacts. It also converges faster than the other three methods and exhibits the lowest overall reconstruction error level, as measured by MSE. Conclusions: For high-noise simulated SPECT data, HOTV-PAPA outperforms TV-PAPA, GPF-EM, and TV-OSL in terms of hot lesion detectability, noise suppression, MSE, and computational efficiency. Unlike TV-PAPA and TV-OSL, HOTV-PAPA does not create sizable staircase artifacts. Moreover, HOTV-PAPA effectively suppresses noise, with only limited loss of local spatial resolution. Of the four methods, HOTV-PAPA shows the best lesion detectability, thanks to its superior noise suppression. HOTV-PAPA shows promise for clinically useful reconstructions of low-dose SPECT data.« less

Effective noise-suppressed and artifact-reduced reconstruction of SPECT data using a preconditioned alternating projection algorithm

PubMed Central

Li, Si; Zhang, Jiahan; Krol, Andrzej; Schmidtlein, C. Ross; Vogelsang, Levon; Shen, Lixin; Lipson, Edward; Feiglin, David; Xu, Yuesheng

2015-01-01

Purpose: The authors have recently developed a preconditioned alternating projection algorithm (PAPA) with total variation (TV) regularizer for solving the penalized-likelihood optimization model for single-photon emission computed tomography (SPECT) reconstruction. This algorithm belongs to a novel class of fixed-point proximity methods. The goal of this work is to investigate how PAPA performs while dealing with realistic noisy SPECT data, to compare its performance with more conventional methods, and to address issues with TV artifacts by proposing a novel form of the algorithm invoking high-order TV regularization, denoted as HOTV-PAPA, which has been explored and studied extensively in the present work. Methods: Using Monte Carlo methods, the authors simulate noisy SPECT data from two water cylinders; one contains lumpy “warm” background and “hot” lesions of various sizes with Gaussian activity distribution, and the other is a reference cylinder without hot lesions. The authors study the performance of HOTV-PAPA and compare it with PAPA using first-order TV regularization (TV-PAPA), the Panin–Zeng–Gullberg one-step-late method with TV regularization (TV-OSL), and an expectation–maximization algorithm with Gaussian postfilter (GPF-EM). The authors select penalty-weights (hyperparameters) by qualitatively balancing the trade-off between resolution and image noise separately for TV-PAPA and TV-OSL. However, the authors arrived at the same penalty-weight value for both of them. The authors set the first penalty-weight in HOTV-PAPA equal to the optimal penalty-weight found for TV-PAPA. The second penalty-weight needed for HOTV-PAPA is tuned by balancing resolution and the severity of staircase artifacts. The authors adjust the Gaussian postfilter to approximately match the local point spread function of GPF-EM and HOTV-PAPA. The authors examine hot lesion detectability, study local spatial resolution, analyze background noise properties, estimate mean square errors (MSEs), and report the convergence speed and computation time. Results: HOTV-PAPA yields the best signal-to-noise ratio, followed by TV-PAPA and TV-OSL/GPF-EM. The local spatial resolution of HOTV-PAPA is somewhat worse than that of TV-PAPA and TV-OSL. Images reconstructed using HOTV-PAPA have the lowest local noise power spectrum (LNPS) amplitudes, followed by TV-PAPA, TV-OSL, and GPF-EM. The LNPS peak of GPF-EM is shifted toward higher spatial frequencies than those for the three other methods. The PAPA-type methods exhibit much lower ensemble noise, ensemble voxel variance, and image roughness. HOTV-PAPA performs best in these categories. Whereas images reconstructed using both TV-PAPA and TV-OSL are degraded by severe staircase artifacts; HOTV-PAPA substantially reduces such artifacts. It also converges faster than the other three methods and exhibits the lowest overall reconstruction error level, as measured by MSE. Conclusions: For high-noise simulated SPECT data, HOTV-PAPA outperforms TV-PAPA, GPF-EM, and TV-OSL in terms of hot lesion detectability, noise suppression, MSE, and computational efficiency. Unlike TV-PAPA and TV-OSL, HOTV-PAPA does not create sizable staircase artifacts. Moreover, HOTV-PAPA effectively suppresses noise, with only limited loss of local spatial resolution. Of the four methods, HOTV-PAPA shows the best lesion detectability, thanks to its superior noise suppression. HOTV-PAPA shows promise for clinically useful reconstructions of low-dose SPECT data. PMID:26233214

Simultaneous Tumor Segmentation, Image Restoration, and Blur Kernel Estimation in PET Using Multiple Regularizations

PubMed Central

Li, Laquan; Wang, Jian; Lu, Wei; Tan, Shan

2016-01-01

Accurate tumor segmentation from PET images is crucial in many radiation oncology applications. Among others, partial volume effect (PVE) is recognized as one of the most important factors degrading imaging quality and segmentation accuracy in PET. Taking into account that image restoration and tumor segmentation are tightly coupled and can promote each other, we proposed a variational method to solve both problems simultaneously in this study. The proposed method integrated total variation (TV) semi-blind de-convolution and Mumford-Shah segmentation with multiple regularizations. Unlike many existing energy minimization methods using either TV or L2 regularization, the proposed method employed TV regularization over tumor edges to preserve edge information, and L2 regularization inside tumor regions to preserve the smooth change of the metabolic uptake in a PET image. The blur kernel was modeled as anisotropic Gaussian to address the resolution difference in transverse and axial directions commonly seen in a clinic PET scanner. The energy functional was rephrased using the Γ-convergence approximation and was iteratively optimized using the alternating minimization (AM) algorithm. The performance of the proposed method was validated on a physical phantom and two clinic datasets with non-Hodgkin’s lymphoma and esophageal cancer, respectively. Experimental results demonstrated that the proposed method had high performance for simultaneous image restoration, tumor segmentation and scanner blur kernel estimation. Particularly, the recovery coefficients (RC) of the restored images of the proposed method in the phantom study were close to 1, indicating an efficient recovery of the original blurred images; for segmentation the proposed method achieved average dice similarity indexes (DSIs) of 0.79 and 0.80 for two clinic datasets, respectively; and the relative errors of the estimated blur kernel widths were less than 19% in the transversal direction and 7% in the axial direction. PMID:28603407

Total generalized variation-regularized variational model for single image dehazing

NASA Astrophysics Data System (ADS)

Shu, Qiao-Ling; Wu, Chuan-Sheng; Zhong, Qiu-Xiang; Liu, Ryan Wen

2018-04-01

Imaging quality is often significantly degraded under hazy weather condition. The purpose of this paper is to recover the latent sharp image from its hazy version. It is well known that the accurate estimation of depth information could assist in improving dehazing performance. In this paper, a detail-preserving variational model was proposed to simultaneously estimate haze-free image and depth map. In particular, the total variation (TV) and total generalized variation (TGV) regularizers were introduced to restrain haze-free image and depth map, respectively. The resulting nonsmooth optimization problem was efficiently solved using the alternating direction method of multipliers (ADMM). Comprehensive experiments have been conducted on realistic datasets to compare our proposed method with several state-of-the-art dehazing methods. Results have illustrated the superior performance of the proposed method in terms of visual quality evaluation.

Nonlocal variational model and filter algorithm to remove multiplicative noise

NASA Astrophysics Data System (ADS)

Chen, Dai-Qiang; Zhang, Hui; Cheng, Li-Zhi

2010-07-01

The nonlocal (NL) means filter proposed by Buades, Coll, and Morel (SIAM Multiscale Model. Simul. 4(2), 490-530, 2005), which makes full use of the redundancy information in images, has shown to be very efficient for image denoising with Gauss noise added. On the basis of the NL method and a striver to minimize the conditional mean-square error, we design a NL means filter to remove multiplicative noise, and combining the NL filter to regularity method, we propose a NL total variational (TV) model and present a fast iterated algorithm for it. Experiments demonstrate that our algorithm is better than TV method; it is superior in preserving small structures and textures and can obtain an improvement in peak signal-to-noise ratio.

The 1985 ARI Survey of Army Recruits: Tabular Description of NPS (active) Army Accessions. Volume 1

DTIC Science & Technology

1987-04-01

T261 -- WATCH TV PROG:NBA BASKETBALL DO YOU WATCH ANY OF THE FOLLOWING PROGRAMS OR PROGRAMMING TYPES ON REGULAR TV STATIONS? .- NBA BASKETBALL . 1...327𔃻 261 WATCH TV PROG:NBA BASKETBALL 328-329 T262 WATCH TV PROG:COLLEGE BASKETBALL 330-331 T263 WATCH TV PROG:NHL HOCKEY 332-333 T264 WlATCH TV...T262 -- WATCH TV PROG:COLLEGE BASKETBALL DO YOU WATCH ANY OF THE FOLLOWING PROGRAMS OR PROGRAMMING TYPES ON REGULAR TV STATIONS? - COLLEGE BASKETBALL . 1

X-Ray Phase Imaging for Breast Cancer Detection

DTIC Science & Technology

2010-09-01

regularization seeks the minimum- norm , least squares solution for phase retrieval. The retrieval result with Tikhonov regularization is still unsatisfactory...of norm , that can effectively reflect the accuracy of the retrieved data as an image, if ‖δ Ik+1−δ Ik‖ is less than a predefined threshold value β...pointed out that the proper norm for images is the total variation (TV) norm , which is the L1 norm of the gradient of the image function, and not the

On epicardial potential reconstruction using regularization schemes with the L1-norm data term.

PubMed

Shou, Guofa; Xia, Ling; Liu, Feng; Jiang, Mingfeng; Crozier, Stuart

2011-01-07

The electrocardiographic (ECG) inverse problem is ill-posed and usually solved by regularization schemes. These regularization methods, such as the Tikhonov method, are often based on the L2-norm data and constraint terms. However, L2-norm-based methods inherently provide smoothed inverse solutions that are sensitive to measurement errors, and also lack the capability of localizing and distinguishing multiple proximal cardiac electrical sources. This paper presents alternative regularization schemes employing the L1-norm data term for the reconstruction of epicardial potentials (EPs) from measured body surface potentials (BSPs). During numerical implementation, the iteratively reweighted norm algorithm was applied to solve the L1-norm-related schemes, and measurement noises were considered in the BSP data. The proposed L1-norm data term-based regularization schemes (with L1 and L2 penalty terms of the normal derivative constraint (labelled as L1TV and L1L2)) were compared with the L2-norm data terms (Tikhonov with zero-order and normal derivative constraints, labelled as ZOT and FOT, and the total variation method labelled as L2TV). The studies demonstrated that, with averaged measurement noise, the inverse solutions provided by the L1L2 and FOT algorithms have less relative error values. However, when larger noise occurred in some electrodes (for example, signal lost during measurement), the L1TV and L1L2 methods can obtain more accurate EPs in a robust manner. Therefore the L1-norm data term-based solutions are generally less perturbed by measurement noises, suggesting that the new regularization scheme is promising for providing practical ECG inverse solutions.

Suntans and Sun Protection in Australian Teen Media: 1999 To 2000

ERIC Educational Resources Information Center

McDermott, Liane J.; Lowe, John B.; Stanton, Warren R.; Clavarino, Alexandra M.

2005-01-01

In this study, the portrayal of tanned skin and sun protection in magazines, television programs, and movies popular with Australian adolescents were analyzed. Images of models in magazines (n = 1,791), regular/supporting characters in television programs (n = 867), and regular/supporting characters in cinema movies (n = 2,836) for the 12-month…

Edge guided image reconstruction in linear scan CT by weighted alternating direction TV minimization.

PubMed

Cai, Ailong; Wang, Linyuan; Zhang, Hanming; Yan, Bin; Li, Lei; Xi, Xiaoqi; Li, Jianxin

2014-01-01

Linear scan computed tomography (CT) is a promising imaging configuration with high scanning efficiency while the data set is under-sampled and angularly limited for which high quality image reconstruction is challenging. In this work, an edge guided total variation minimization reconstruction (EGTVM) algorithm is developed in dealing with this problem. The proposed method is modeled on the combination of total variation (TV) regularization and iterative edge detection strategy. In the proposed method, the edge weights of intermediate reconstructions are incorporated into the TV objective function. The optimization is efficiently solved by applying alternating direction method of multipliers. A prudential and conservative edge detection strategy proposed in this paper can obtain the true edges while restricting the errors within an acceptable degree. Based on the comparison on both simulation studies and real CT data set reconstructions, EGTVM provides comparable or even better quality compared to the non-edge guided reconstruction and adaptive steepest descent-projection onto convex sets method. With the utilization of weighted alternating direction TV minimization and edge detection, EGTVM achieves fast and robust convergence and reconstructs high quality image when applied in linear scan CT with under-sampled data set.

Does TV viewing during family meals make a difference in adolescent substance use?

PubMed

Eisenberg, Marla E; Neumark-Sztainer, Dianne; Feldman, Shira

2009-06-01

Family meals are important to adolescent health, but relatively little is known about TV viewing during family meals. The present paper examines the role that TV viewing during family meals may have on substance use behaviors among adolescents. A diverse sample of 806 Minnesota high school students (mean age 17.2 years) provided survey data in 2003-2004 regarding family meal frequency, substance use behavior and general family connectedness. General linear modeling was used to compare substance use across three family meal/TV categories in a cross-sectional analysis. 28.6% of participants ate regular family meals without TV, and 27.5% had regular family meals while watching TV. Significant differences in cigarette smoking, alcohol and marijuana use were found for females reporting regular family meals versus no regular family meals, but did not differ significantly by TV viewing. No significant differences were found across groups of males. Results from this study indicate that TV viewing during family meals does not appear to attenuate the previously observed protective relationship between family meals and substance use for females. Benefits of family meals may be derived simply from having adolescents at home during mealtimes.

Hessian Schatten-norm regularization for linear inverse problems.

PubMed

Lefkimmiatis, Stamatios; Ward, John Paul; Unser, Michael

2013-05-01

We introduce a novel family of invariant, convex, and non-quadratic functionals that we employ to derive regularized solutions of ill-posed linear inverse imaging problems. The proposed regularizers involve the Schatten norms of the Hessian matrix, which are computed at every pixel of the image. They can be viewed as second-order extensions of the popular total-variation (TV) semi-norm since they satisfy the same invariance properties. Meanwhile, by taking advantage of second-order derivatives, they avoid the staircase effect, a common artifact of TV-based reconstructions, and perform well for a wide range of applications. To solve the corresponding optimization problems, we propose an algorithm that is based on a primal-dual formulation. A fundamental ingredient of this algorithm is the projection of matrices onto Schatten norm balls of arbitrary radius. This operation is performed efficiently based on a direct link we provide between vector projections onto lq norm balls and matrix projections onto Schatten norm balls. Finally, we demonstrate the effectiveness of the proposed methods through experimental results on several inverse imaging problems with real and simulated data.

Televised Dance: Evaluation of Three Approaches.

ERIC Educational Resources Information Center

Oglesbee, Frank W.

A study was conducted to determine whether dance-trained, television-trained, and regular television viewing audiences would evaluate different approaches to televising dance differently. Three versions of a dance performance were videotaped: (1) version A, a one-camera, one-shot recording; (2) version B, a two-camera, real-time-edited approach,…

Helping Parents Reduce Children's Television Viewing

ERIC Educational Resources Information Center

Jason, Leonard A.; Fries, Michael

2004-01-01

Parents and educators around the country are concerned about the amount of time children watch television. Part of this concern stems from the fact that a considerable amount of violence is regularly portrayed on television. In addition, those youngsters who watch an excessive amount of television have little time for developing other interests…

Estimation of Noise Properties for TV-regularized Image Reconstruction in Computed Tomography

PubMed Central

Sánchez, Adrian A.

2016-01-01

A method for predicting the image covariance resulting from total-variation-penalized iterative image reconstruction (TV-penalized IIR) is presented and demonstrated in a variety of contexts. The method is validated against the sample covariance from statistical noise realizations for a small image using a variety of comparison metrics. Potential applications for the covariance approximation include investigation of image properties such as object- and signal-dependence of noise, and noise stationarity. These applications are demonstrated, along with the construction of image pixel variance maps for two-dimensional 128 × 128 pixel images. Methods for extending the proposed covariance approximation to larger images and improving computational efficiency are discussed. Future work will apply the developed methodology to the construction of task-based image quality metrics such as the Hotelling observer detectability for TV-based IIR. PMID:26308968

Estimation of noise properties for TV-regularized image reconstruction in computed tomography.

PubMed

Sánchez, Adrian A

2015-09-21

A method for predicting the image covariance resulting from total-variation-penalized iterative image reconstruction (TV-penalized IIR) is presented and demonstrated in a variety of contexts. The method is validated against the sample covariance from statistical noise realizations for a small image using a variety of comparison metrics. Potential applications for the covariance approximation include investigation of image properties such as object- and signal-dependence of noise, and noise stationarity. These applications are demonstrated, along with the construction of image pixel variance maps for two-dimensional 128 × 128 pixel images. Methods for extending the proposed covariance approximation to larger images and improving computational efficiency are discussed. Future work will apply the developed methodology to the construction of task-based image quality metrics such as the Hotelling observer detectability for TV-based IIR.

Estimation of noise properties for TV-regularized image reconstruction in computed tomography

NASA Astrophysics Data System (ADS)

Sánchez, Adrian A.

2015-09-01

A method for predicting the image covariance resulting from total-variation-penalized iterative image reconstruction (TV-penalized IIR) is presented and demonstrated in a variety of contexts. The method is validated against the sample covariance from statistical noise realizations for a small image using a variety of comparison metrics. Potential applications for the covariance approximation include investigation of image properties such as object- and signal-dependence of noise, and noise stationarity. These applications are demonstrated, along with the construction of image pixel variance maps for two-dimensional 128× 128 pixel images. Methods for extending the proposed covariance approximation to larger images and improving computational efficiency are discussed. Future work will apply the developed methodology to the construction of task-based image quality metrics such as the Hotelling observer detectability for TV-based IIR.

Moving object detection via low-rank total variation regularization

NASA Astrophysics Data System (ADS)

Wang, Pengcheng; Chen, Qian; Shao, Na

2016-09-01

Moving object detection is a challenging task in video surveillance. Recently proposed Robust Principal Component Analysis (RPCA) can recover the outlier patterns from the low-rank data under some mild conditions. However, the l-penalty in RPCA doesn't work well in moving object detection because the irrepresentable condition is often not satisfied. In this paper, a method based on total variation (TV) regularization scheme is proposed. In our model, image sequences captured with a static camera are highly related, which can be described using a low-rank matrix. Meanwhile, the low-rank matrix can absorb background motion, e.g. periodic and random perturbation. The foreground objects in the sequence are usually sparsely distributed and drifting continuously, and can be treated as group outliers from the highly-related background scenes. Instead of l-penalty, we exploit the total variation of the foreground. By minimizing the total variation energy, the outliers tend to collapse and finally converge to be the exact moving objects. The TV-penalty is superior to the l-penalty especially when the outlier is in the majority for some pixels, and our method can estimate the outlier explicitly with less bias but higher variance. To solve the problem, a joint optimization function is formulated and can be effectively solved through the inexact Augmented Lagrange Multiplier (ALM) method. We evaluate our method along with several state-of-the-art approaches in MATLAB. Both qualitative and quantitative results demonstrate that our proposed method works effectively on a large range of complex scenarios.

Self-regulation and household routines at age three and obesity at age eleven: longitudinal analysis of the UK Millennium Cohort Study

PubMed Central

Anderson, Sarah E; Sacker, Amanda; Whitaker, Robert C; Kelly, Yvonne

2017-01-01

Objective To examine, in a population-based cohort of three-year-old children, the association between self-regulation and exposure to the household routines of regular bedtime, regular mealtime, and limits on watching television/video; and to determine whether self-regulation and these routines predict the risk of obesity at age 11. Methods Analyses included 10 955 children in the nationally-representative UK Millennium Cohort Study. When children were age 3, parents reported whether children had a regular bedtime and mealtime and the amount of television/video watched. Emotional and cognitive self-regulation at age 3 were assessed by parent-report with the Child Social Behaviour Questionnaire. Children’s height and weight were measured at age 11 and obesity was defined using the International Obesity Task Force (IOTF) criteria. Results At age 3, 41% of children always had a regular bedtime, 47% always had a regular mealtime, and 23% were limited to ≤1 hour television/video daily. At age 11, 6.2% of children were obese. All three household routines were significantly associated with better emotional self-regulation, but not better cognitive self-regulation. In a multi-variable logistic regression model including emotional and cognitive self-regulation, all routines, and controlling for sociodemographic covariates, a 1 unit difference in emotional self-regulation at age 3 was associated with an OR (95% CI) for obesity of 1.38 (1.11, 1.71) at age 11, and inconsistent bedtimes with an OR (95% CI) for obesity of 1.87 (1.39, 2.51) at age 11. There was no evidence that emotional self-regulation mediated the relationship between regular bedtimes and later obesity. Cognitive self-regulation was not associated with later obesity. Conclusions Three-year-old children who had regular bedtimes, mealtimes, and limits on their television/video time had better emotional self-regulation. Lack of a regular bedtime and poorer emotional self-regulation at age 3 were independent predictors of obesity at age 11. PMID:28435162

47 CFR 74.763 - Time of operation.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.763 Time of operation. (a) A low power TV, TV translator, or TV booster station is not required to adhere to any regular schedule of operation. However, the licensee of a TV translator...

Iterative image reconstruction for multienergy computed tomography via structure tensor total variation regularization

NASA Astrophysics Data System (ADS)

Zeng, Dong; Bian, Zhaoying; Gong, Changfei; Huang, Jing; He, Ji; Zhang, Hua; Lu, Lijun; Feng, Qianjin; Liang, Zhengrong; Ma, Jianhua

2016-03-01

Multienergy computed tomography (MECT) has the potential to simultaneously offer multiple sets of energy- selective data belonging to specific energy windows. However, because sufficient photon counts are not available in the specific energy windows compared with that in the whole energy window, the MECT images reconstructed by the analytical approach often suffer from poor signal-to-noise (SNR) and strong streak artifacts. To eliminate this drawback, in this work we present a penalized weighted least-squares (PWLS) scheme by incorporating the new concept of structure tensor total variation (STV) regularization to improve the MECT images quality from low-milliampere-seconds (low-mAs) data acquisitions. Henceforth the present scheme is referred to as `PWLS- STV' for simplicity. Specifically, the STV regularization is derived by penalizing the eigenvalues of the structure tensor of every point in the MECT images. Thus it can provide more robust measures of image variation, which can eliminate the patchy artifacts often observed in total variation regularization. Subsequently, an alternating optimization algorithm was adopted to minimize the objective function. Experiments with a digital XCAT phantom clearly demonstrate that the present PWLS-STV algorithm can achieve more gains than the existing TV-based algorithms and the conventional filtered backpeojection (FBP) algorithm in terms of noise-induced artifacts suppression, resolution preservation, and material decomposition assessment.

Image super-resolution via adaptive filtering and regularization

NASA Astrophysics Data System (ADS)

Ren, Jingbo; Wu, Hao; Dong, Weisheng; Shi, Guangming

2014-11-01

Image super-resolution (SR) is widely used in the fields of civil and military, especially for the low-resolution remote sensing images limited by the sensor. Single-image SR refers to the task of restoring a high-resolution (HR) image from the low-resolution image coupled with some prior knowledge as a regularization term. One classic method regularizes image by total variation (TV) and/or wavelet or some other transform which introduce some artifacts. To compress these shortages, a new framework for single image SR is proposed by utilizing an adaptive filter before regularization. The key of our model is that the adaptive filter is used to remove the spatial relevance among pixels first and then only the high frequency (HF) part, which is sparser in TV and transform domain, is considered as the regularization term. Concretely, through transforming the original model, the SR question can be solved by two alternate iteration sub-problems. Before each iteration, the adaptive filter should be updated to estimate the initial HF. A high quality HF part and HR image can be obtained by solving the first and second sub-problem, respectively. In experimental part, a set of remote sensing images captured by Landsat satellites are tested to demonstrate the effectiveness of the proposed framework. Experimental results show the outstanding performance of the proposed method in quantitative evaluation and visual fidelity compared with the state-of-the-art methods.

A MAP blind image deconvolution algorithm with bandwidth over-constrained

NASA Astrophysics Data System (ADS)

Ren, Zhilei; Liu, Jin; Liang, Yonghui; He, Yulong

2018-03-01

We demonstrate a maximum a posteriori (MAP) blind image deconvolution algorithm with bandwidth over-constrained and total variation (TV) regularization to recover a clear image from the AO corrected images. The point spread functions (PSFs) are estimated by bandwidth limited less than the cutoff frequency of the optical system. Our algorithm performs well in avoiding noise magnification. The performance is demonstrated on simulated data.

Television News as Drama: An International Perspective.

ERIC Educational Resources Information Center

Breen, Myles P.

An observer can identify a trend in television news presentation style toward the dramatic, not only in the sets and the personnel, but more importantly in the choice of what is deemed newsworthy. A thesis is proposed by many suggesting that television is a regular ritual of many viewers of which news is a minor part and that television's first…

A mixed-order nonlinear diffusion compressed sensing MR image reconstruction.

PubMed

Joy, Ajin; Paul, Joseph Suresh

2018-03-07

Avoid formation of staircase artifacts in nonlinear diffusion-based MR image reconstruction without compromising computational speed. Whereas second-order diffusion encourages the evolution of pixel neighborhood with uniform intensities, fourth-order diffusion considers smooth region to be not necessarily a uniform intensity region but also a planar region. Therefore, a controlled application of fourth-order diffusivity function is used to encourage second-order diffusion to reconstruct the smooth regions of the image as a plane rather than a group of blocks, while not being strong enough to introduce the undesirable speckle effect. Proposed method is compared with second- and fourth-order nonlinear diffusion reconstruction, total variation (TV), total generalized variation, and higher degree TV using in vivo data sets for different undersampling levels with application to dictionary learning-based reconstruction. It is observed that the proposed technique preserves sharp boundaries in the image while preventing the formation of staircase artifacts in the regions of smoothly varying pixel intensities. It also shows reduced error measures compared with second-order nonlinear diffusion reconstruction or TV and converges faster than TV-based methods. Because nonlinear diffusion is known to be an effective alternative to TV for edge-preserving reconstruction, the crucial aspect of staircase artifact removal is addressed. Reconstruction is found to be stable for the experimentally determined range of fourth-order regularization parameter, and therefore not does not introduce a parameter search. Hence, the computational simplicity of second-order diffusion is retained. © 2018 International Society for Magnetic Resonance in Medicine.

Can Television Enhance Children's Mathematical Problem Solving?

ERIC Educational Resources Information Center

Fisch, Shalom M.; And Others

1994-01-01

A summative evaluation of "Square One TV," an educational mathematics series produced by the Children's Television Workshop, shows that children who regularly viewed the program showed significant improvement in solving unfamiliar, complex mathematical problems, and viewers showed improvement in their mathematical problem-solving ability…

Spherical Deconvolution of Multichannel Diffusion MRI Data with Non-Gaussian Noise Models and Spatial Regularization

PubMed Central

Canales-Rodríguez, Erick J.; Caruyer, Emmanuel; Aja-Fernández, Santiago; Radua, Joaquim; Yurramendi Mendizabal, Jesús M.; Iturria-Medina, Yasser; Melie-García, Lester; Alemán-Gómez, Yasser; Thiran, Jean-Philippe; Sarró, Salvador; Pomarol-Clotet, Edith; Salvador, Raymond

2015-01-01

Spherical deconvolution (SD) methods are widely used to estimate the intra-voxel white-matter fiber orientations from diffusion MRI data. However, while some of these methods assume a zero-mean Gaussian distribution for the underlying noise, its real distribution is known to be non-Gaussian and to depend on many factors such as the number of coils and the methodology used to combine multichannel MRI signals. Indeed, the two prevailing methods for multichannel signal combination lead to noise patterns better described by Rician and noncentral Chi distributions. Here we develop a Robust and Unbiased Model-BAsed Spherical Deconvolution (RUMBA-SD) technique, intended to deal with realistic MRI noise, based on a Richardson-Lucy (RL) algorithm adapted to Rician and noncentral Chi likelihood models. To quantify the benefits of using proper noise models, RUMBA-SD was compared with dRL-SD, a well-established method based on the RL algorithm for Gaussian noise. Another aim of the study was to quantify the impact of including a total variation (TV) spatial regularization term in the estimation framework. To do this, we developed TV spatially-regularized versions of both RUMBA-SD and dRL-SD algorithms. The evaluation was performed by comparing various quality metrics on 132 three-dimensional synthetic phantoms involving different inter-fiber angles and volume fractions, which were contaminated with noise mimicking patterns generated by data processing in multichannel scanners. The results demonstrate that the inclusion of proper likelihood models leads to an increased ability to resolve fiber crossings with smaller inter-fiber angles and to better detect non-dominant fibers. The inclusion of TV regularization dramatically improved the resolution power of both techniques. The above findings were also verified in human brain data. PMID:26470024

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akiyama, Kazunori; Fish, Vincent L.; Doeleman, Sheperd S.

We propose a new imaging technique for radio and optical/infrared interferometry. The proposed technique reconstructs the image from the visibility amplitude and closure phase, which are standard data products of short-millimeter very long baseline interferometers such as the Event Horizon Telescope (EHT) and optical/infrared interferometers, by utilizing two regularization functions: the ℓ {sub 1}-norm and total variation (TV) of the brightness distribution. In the proposed method, optimal regularization parameters, which represent the sparseness and effective spatial resolution of the image, are derived from data themselves using cross-validation (CV). As an application of this technique, we present simulated observations of M87more » with the EHT based on four physically motivated models. We confirm that ℓ {sub 1} + TV regularization can achieve an optimal resolution of ∼20%–30% of the diffraction limit λ / D {sub max}, which is the nominal spatial resolution of a radio interferometer. With the proposed technique, the EHT can robustly and reasonably achieve super-resolution sufficient to clearly resolve the black hole shadow. These results make it promising for the EHT to provide an unprecedented view of the event-horizon-scale structure in the vicinity of the supermassive black hole in M87 and also the Galactic center Sgr A*.« less

Short-Term Effects of Televised Aggression on Children's Behavior.

ERIC Educational Resources Information Center

Liebert, Robert M.; Baron, Robert A.

Recently collected data appear to warrant advancing some tentative conslusions concerning the short-term effects of violence in television on children: 1) children are exposed to a substantial amount of violent content on television, and they can remember and learn from such exposure; 2) correlational studies have disclosed a regular association…

47 CFR 76.614 - Cable television system regular monitoring.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-137 and 225-400 MHz shall provide for a program of regular monitoring for signal leakage by... in these bands of 20 uV/m or greater at a distance of 3 meters. During regular monitoring, any leakage source which produces a field strength of 20 uV/m or greater at a distance of 3 meters in the...

Accelerated 1 H MRSI using randomly undersampled spiral-based k-space trajectories.

PubMed

Chatnuntawech, Itthi; Gagoski, Borjan; Bilgic, Berkin; Cauley, Stephen F; Setsompop, Kawin; Adalsteinsson, Elfar

2014-07-30

To develop and evaluate the performance of an acquisition and reconstruction method for accelerated MR spectroscopic imaging (MRSI) through undersampling of spiral trajectories. A randomly undersampled spiral acquisition and sensitivity encoding (SENSE) with total variation (TV) regularization, random SENSE+TV, is developed and evaluated on single-slice numerical phantom, in vivo single-slice MRSI, and in vivo three-dimensional (3D)-MRSI at 3 Tesla. Random SENSE+TV was compared with five alternative methods for accelerated MRSI. For the in vivo single-slice MRSI, random SENSE+TV yields up to 2.7 and 2 times reduction in root-mean-square error (RMSE) of reconstructed N-acetyl aspartate (NAA), creatine, and choline maps, compared with the denoised fully sampled and uniformly undersampled SENSE+TV methods with the same acquisition time, respectively. For the in vivo 3D-MRSI, random SENSE+TV yields up to 1.6 times reduction in RMSE, compared with uniform SENSE+TV. Furthermore, by using random SENSE+TV, we have demonstrated on the in vivo single-slice and 3D-MRSI that acceleration factors of 4.5 and 4 are achievable with the same quality as the fully sampled data, as measured by RMSE of reconstructed NAA map, respectively. With the same scan time, random SENSE+TV yields lower RMSEs of metabolite maps than other methods evaluated. Random SENSE+TV achieves up to 4.5-fold acceleration with comparable data quality as the fully sampled acquisition. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Computed inverse resonance imaging for magnetic susceptibility map reconstruction.

PubMed

Chen, Zikuan; Calhoun, Vince

2012-01-01

This article reports a computed inverse magnetic resonance imaging (CIMRI) model for reconstructing the magnetic susceptibility source from MRI data using a 2-step computational approach. The forward T2*-weighted MRI (T2*MRI) process is broken down into 2 steps: (1) from magnetic susceptibility source to field map establishment via magnetization in the main field and (2) from field map to MR image formation by intravoxel dephasing average. The proposed CIMRI model includes 2 inverse steps to reverse the T2*MRI procedure: field map calculation from MR-phase image and susceptibility source calculation from the field map. The inverse step from field map to susceptibility map is a 3-dimensional ill-posed deconvolution problem, which can be solved with 3 kinds of approaches: the Tikhonov-regularized matrix inverse, inverse filtering with a truncated filter, and total variation (TV) iteration. By numerical simulation, we validate the CIMRI model by comparing the reconstructed susceptibility maps for a predefined susceptibility source. Numerical simulations of CIMRI show that the split Bregman TV iteration solver can reconstruct the susceptibility map from an MR-phase image with high fidelity (spatial correlation ≈ 0.99). The split Bregman TV iteration solver includes noise reduction, edge preservation, and image energy conservation. For applications to brain susceptibility reconstruction, it is important to calibrate the TV iteration program by selecting suitable values of the regularization parameter. The proposed CIMRI model can reconstruct the magnetic susceptibility source of T2*MRI by 2 computational steps: calculating the field map from the phase image and reconstructing the susceptibility map from the field map. The crux of CIMRI lies in an ill-posed 3-dimensional deconvolution problem, which can be effectively solved by the split Bregman TV iteration algorithm.

Computed inverse MRI for magnetic susceptibility map reconstruction

PubMed Central

Chen, Zikuan; Calhoun, Vince

2015-01-01

Objective This paper reports on a computed inverse magnetic resonance imaging (CIMRI) model for reconstructing the magnetic susceptibility source from MRI data using a two-step computational approach. Methods The forward T2*-weighted MRI (T2*MRI) process is decomposed into two steps: 1) from magnetic susceptibility source to fieldmap establishment via magnetization in a main field, and 2) from fieldmap to MR image formation by intravoxel dephasing average. The proposed CIMRI model includes two inverse steps to reverse the T2*MRI procedure: fieldmap calculation from MR phase image and susceptibility source calculation from the fieldmap. The inverse step from fieldmap to susceptibility map is a 3D ill-posed deconvolution problem, which can be solved by three kinds of approaches: Tikhonov-regularized matrix inverse, inverse filtering with a truncated filter, and total variation (TV) iteration. By numerical simulation, we validate the CIMRI model by comparing the reconstructed susceptibility maps for a predefined susceptibility source. Results Numerical simulations of CIMRI show that the split Bregman TV iteration solver can reconstruct the susceptibility map from a MR phase image with high fidelity (spatial correlation≈0.99). The split Bregman TV iteration solver includes noise reduction, edge preservation, and image energy conservation. For applications to brain susceptibility reconstruction, it is important to calibrate the TV iteration program by selecting suitable values of the regularization parameter. Conclusions The proposed CIMRI model can reconstruct the magnetic susceptibility source of T2*MRI by two computational steps: calculating the fieldmap from the phase image and reconstructing the susceptibility map from the fieldmap. The crux of CIMRI lies in an ill-posed 3D deconvolution problem, which can be effectively solved by the split Bregman TV iteration algorithm. PMID:22446372

Limited angle CT reconstruction by simultaneous spatial and Radon domain regularization based on TV and data-driven tight frame

NASA Astrophysics Data System (ADS)

Zhang, Wenkun; Zhang, Hanming; Wang, Linyuan; Cai, Ailong; Li, Lei; Yan, Bin

2018-02-01

Limited angle computed tomography (CT) reconstruction is widely performed in medical diagnosis and industrial testing because of the size of objects, engine/armor inspection requirements, and limited scan flexibility. Limited angle reconstruction necessitates usage of optimization-based methods that utilize additional sparse priors. However, most of conventional methods solely exploit sparsity priors of spatial domains. When CT projection suffers from serious data deficiency or various noises, obtaining reconstruction images that meet the requirement of quality becomes difficult and challenging. To solve this problem, this paper developed an adaptive reconstruction method for limited angle CT problem. The proposed method simultaneously uses spatial and Radon domain regularization model based on total variation (TV) and data-driven tight frame. Data-driven tight frame being derived from wavelet transformation aims at exploiting sparsity priors of sinogram in Radon domain. Unlike existing works that utilize pre-constructed sparse transformation, the framelets of the data-driven regularization model can be adaptively learned from the latest projection data in the process of iterative reconstruction to provide optimal sparse approximations for given sinogram. At the same time, an effective alternating direction method is designed to solve the simultaneous spatial and Radon domain regularization model. The experiments for both simulation and real data demonstrate that the proposed algorithm shows better performance in artifacts depression and details preservation than the algorithms solely using regularization model of spatial domain. Quantitative evaluations for the results also indicate that the proposed algorithm applying learning strategy performs better than the dual domains algorithms without learning regularization model

A TVSCAD approach for image deblurring with impulsive noise

NASA Astrophysics Data System (ADS)

Gu, Guoyong; Jiang, Suhong; Yang, Junfeng

2017-12-01

We consider image deblurring problem in the presence of impulsive noise. It is known that total variation (TV) regularization with L1-norm penalized data fitting (TVL1 for short) works reasonably well only when the level of impulsive noise is relatively low. For high level impulsive noise, TVL1 works poorly. The reason is that all data, both corrupted and noise free, are equally penalized in data fitting, leading to insurmountable difficulty in balancing regularization and data fitting. In this paper, we propose to combine TV regularization with nonconvex smoothly clipped absolute deviation (SCAD) penalty for data fitting (TVSCAD for short). Our motivation is simply that data fitting should be enforced only when an observed data is not severely corrupted, while for those data more likely to be severely corrupted, less or even null penalization should be enforced. A difference of convex functions algorithm is adopted to solve the nonconvex TVSCAD model, resulting in solving a sequence of TVL1-equivalent problems, each of which can then be solved efficiently by the alternating direction method of multipliers. Theoretically, we establish global convergence to a critical point of the nonconvex objective function. The R-linear and at-least-sublinear convergence rate results are derived for the cases of anisotropic and isotropic TV, respectively. Numerically, experimental results are given to show that the TVSCAD approach improves those of the TVL1 significantly, especially for cases with high level impulsive noise, and is comparable with the recently proposed iteratively corrected TVL1 method (Bai et al 2016 Inverse Problems 32 085004).

Accurate sparse-projection image reconstruction via nonlocal TV regularization.

PubMed

Zhang, Yi; Zhang, Weihua; Zhou, Jiliu

2014-01-01

Sparse-projection image reconstruction is a useful approach to lower the radiation dose; however, the incompleteness of projection data will cause degeneration of imaging quality. As a typical compressive sensing method, total variation has obtained great attention on this problem. Suffering from the theoretical imperfection, total variation will produce blocky effect on smooth regions and blur edges. To overcome this problem, in this paper, we introduce the nonlocal total variation into sparse-projection image reconstruction and formulate the minimization problem with new nonlocal total variation norm. The qualitative and quantitative analyses of numerical as well as clinical results demonstrate the validity of the proposed method. Comparing to other existing methods, our method more efficiently suppresses artifacts caused by low-rank reconstruction and reserves structure information better.

Suntans and sun protection in Australian teen media: 1999 to 2000.

PubMed

McDermott, Liane J; Lowe, John B; Stanton, Warren R; Clavarino, Alexandra M

2005-08-01

In this study, the portrayal of tanned skin and sun protection in magazines, television programs, and movies popular with Australian adolescents were analyzed. Images of models in magazines (n = 1,791), regular/supporting characters in television programs (n = 867), and regular/supporting characters in cinema movies (n = 2,836)for the 12-month period August 1999 to July 2000 were coded and analyzed. A light tan was the most predominant tan level, and protective clothing was the most common sun protection measure displayed across all forms of media. There were significant associations between gender and tan levels in the television and movie samples. Although it is important to monitor the portrayal of tan levels and sun protection measures in media targeting adolescents, overall, the authors' findings revealed a media environment generally supportive of sun protection objectives.

CATV and the Broadcasters.

ERIC Educational Resources Information Center

Flanagan, Bill

Competition between cable television systems (CATV) and regular broadcast stations concerns pay-TV and distant signal importation. The pay-TV that CATV provides competes with the networks by "siphoning" away sports and feature films, while the distant signals that CATV imports to a local market "fragment" the local audience and…

Low-illumination image denoising method for wide-area search of nighttime sea surface

NASA Astrophysics Data System (ADS)

Song, Ming-zhu; Qu, Hong-song; Zhang, Gui-xiang; Tao, Shu-ping; Jin, Guang

2018-05-01

In order to suppress complex mixing noise in low-illumination images for wide-area search of nighttime sea surface, a model based on total variation (TV) and split Bregman is proposed in this paper. A fidelity term based on L1 norm and a fidelity term based on L2 norm are designed considering the difference between various noise types, and the regularization mixed first-order TV and second-order TV are designed to balance the influence of details information such as texture and edge for sea surface image. The final detection result is obtained by using the high-frequency component solved from L1 norm and the low-frequency component solved from L2 norm through wavelet transform. The experimental results show that the proposed denoising model has perfect denoising performance for artificially degraded and low-illumination images, and the result of image quality assessment index for the denoising image is superior to that of the contrastive models.

A fast 4D cone beam CT reconstruction method based on the OSC-TV algorithm.

PubMed

Mascolo-Fortin, Julia; Matenine, Dmitri; Archambault, Louis; Després, Philippe

2018-01-01

Four-dimensional cone beam computed tomography allows for temporally resolved imaging with useful applications in radiotherapy, but raises particular challenges in terms of image quality and computation time. The purpose of this work is to develop a fast and accurate 4D algorithm by adapting a GPU-accelerated ordered subsets convex algorithm (OSC), combined with the total variation minimization regularization technique (TV). Different initialization schemes were studied to adapt the OSC-TV algorithm to 4D reconstruction: each respiratory phase was initialized either with a 3D reconstruction or a blank image. Reconstruction algorithms were tested on a dynamic numerical phantom and on a clinical dataset. 4D iterations were implemented for a cluster of 8 GPUs. All developed methods allowed for an adequate visualization of the respiratory movement and compared favorably to the McKinnon-Bates and adaptive steepest descent projection onto convex sets algorithms, while the 4D reconstructions initialized from a prior 3D reconstruction led to better overall image quality. The most suitable adaptation of OSC-TV to 4D CBCT was found to be a combination of a prior FDK reconstruction and a 4D OSC-TV reconstruction with a reconstruction time of 4.5 minutes. This relatively short reconstruction time could facilitate a clinical use.

The Total Variation Regularized L1 Model for Multiscale Decomposition

DTIC Science & Technology

2006-01-01

L1 fidelity term, and presented impressive and successful applications of the TV-L1 model to impulsive noise removal and outlier identification. She...used to filter 1D signal [3], to remove impulsive (salt-n- pepper) noise [35], to extract textures from natural images [45], to remove varying...34, 35, 36] discovery of the usefulness of this model for removing impul- sive noise , Chan and Esedoglu’s [17] further analysis of this model, and a

Sparsity-based acoustic inversion in cross-sectional multiscale optoacoustic imaging.

PubMed

Han, Yiyong; Tzoumas, Stratis; Nunes, Antonio; Ntziachristos, Vasilis; Rosenthal, Amir

2015-09-01

With recent advancement in hardware of optoacoustic imaging systems, highly detailed cross-sectional images may be acquired at a single laser shot, thus eliminating motion artifacts. Nonetheless, other sources of artifacts remain due to signal distortion or out-of-plane signals. The purpose of image reconstruction algorithms is to obtain the most accurate images from noisy, distorted projection data. In this paper, the authors use the model-based approach for acoustic inversion, combined with a sparsity-based inversion procedure. Specifically, a cost function is used that includes the L1 norm of the image in sparse representation and a total variation (TV) term. The optimization problem is solved by a numerically efficient implementation of a nonlinear gradient descent algorithm. TV-L1 model-based inversion is tested in the cross section geometry for numerically generated data as well as for in vivo experimental data from an adult mouse. In all cases, model-based TV-L1 inversion showed a better performance over the conventional Tikhonov regularization, TV inversion, and L1 inversion. In the numerical examples, the images reconstructed with TV-L1 inversion were quantitatively more similar to the originating images. In the experimental examples, TV-L1 inversion yielded sharper images and weaker streak artifact. The results herein show that TV-L1 inversion is capable of improving the quality of highly detailed, multiscale optoacoustic images obtained in vivo using cross-sectional imaging systems. As a result of its high fidelity, model-based TV-L1 inversion may be considered as the new standard for image reconstruction in cross-sectional imaging.

Dissemination of Continuing Education Materials Via Television Delivery Systems. Final Technical Report and Final Report.

ERIC Educational Resources Information Center

Munushian, Jack

In 1972, the University of Southern California School of Engineering established a 4-channel interactive instructional television network. It was designed to allow employees of participating industries to take regular university science and engineering courses and special continuing education courses at or near their work locations. Final progress…

The 1984 ARI Survey of Army Recruits: Tabular Description of NPS Army Reserve Accessions. Volume 2

DTIC Science & Technology

1986-05-01

12 PROB. 0.1867 I 186 T261 — NATCH TV PROG’NBA BASKETBALL NARK ONE LETTER FOR EACH OF THE FOLLOWING PROGRAMS OR PROGRAMMING TYPES ON TV: NBA ...Major league baseball — regular seaaon games 105. Major league baaaball playoffs 106. World Series 107. NBA baaketball 106. College basketball 109...BASEBALL PLAYOFFS HATCH TV PROG:WORLD SERIES HATCH TV PROG:NBA BASKETBALL HATCH TV PROG:COLLEGE BASKETBALL HATCH TV PROG:NHL HOCKEY HATCH TV

A second order derivative scheme based on Bregman algorithm class

NASA Astrophysics Data System (ADS)

Campagna, Rosanna; Crisci, Serena; Cuomo, Salvatore; Galletti, Ardelio; Marcellino, Livia

2016-10-01

The algorithms based on the Bregman iterative regularization are known for efficiently solving convex constraint optimization problems. In this paper, we introduce a second order derivative scheme for the class of Bregman algorithms. Its properties of convergence and stability are investigated by means of numerical evidences. Moreover, we apply the proposed scheme to an isotropic Total Variation (TV) problem arising out of the Magnetic Resonance Image (MRI) denoising. Experimental results confirm that our algorithm has good performance in terms of denoising quality, effectiveness and robustness.

Multiscale properties of weighted total variation flow with applications to denoising and registration.

PubMed

Athavale, Prashant; Xu, Robert; Radau, Perry; Nachman, Adrian; Wright, Graham A

2015-07-01

Images consist of structures of varying scales: large scale structures such as flat regions, and small scale structures such as noise, textures, and rapidly oscillatory patterns. In the hierarchical (BV, L(2)) image decomposition, Tadmor, et al. (2004) start with extracting coarse scale structures from a given image, and successively extract finer structures from the residuals in each step of the iterative decomposition. We propose to begin instead by extracting the finest structures from the given image and then proceed to extract increasingly coarser structures. In most images, noise could be considered as a fine scale structure. Thus, starting the image decomposition with finer scales, rather than large scales, leads to fast denoising. We note that our approach turns out to be equivalent to the nonstationary regularization in Scherzer and Weickert (2000). The continuous limit of this procedure leads to a time-scaled version of total variation flow. Motivated by specific clinical applications, we introduce an image depending weight in the regularization functional, and study the corresponding weighted TV flow. We show that the edge-preserving property of the multiscale representation of an input image obtained with the weighted TV flow can be enhanced and localized by appropriate choice of the weight. We use this in developing an efficient and edge-preserving denoising algorithm with control on speed and localization properties. We examine analytical properties of the weighted TV flow that give precise information about the denoising speed and the rate of change of energy of the images. An additional contribution of the paper is to use the images obtained at different scales for robust multiscale registration. We show that the inherently multiscale nature of the weighted TV flow improved performance for registration of noisy cardiac MRI images, compared to other methods such as bilateral or Gaussian filtering. A clinical application of the multiscale registration algorithm is also demonstrated for aligning viability assessment magnetic resonance (MR) images from 8 patients with previous myocardial infarctions. Copyright © 2015. Published by Elsevier B.V.

Self-Directed English Language Learning through Watching English Television Drama in China

ERIC Educational Resources Information Center

Wang, Danping

2012-01-01

This paper presents a case study of a group of Chinese ESL learners in China, who study English by immersing themselves regularly and rigorously in English television drama. A self-directed learning pedagogy has been developed and discussed, which seems to have signposted an effective and economic way for ESL learners to improve linguistic,…

Physical Attractiveness Stereotyping on American Television Programs: A Content Analysis.

ERIC Educational Resources Information Center

Downs, A. Chris; Harrison, Sheila K.

The frequencies of specific types of verbal attractiveness stereotypes portrayed on television commercials and regular programs were determined in two studies. In the first, the 4,294 commercials aired between 8 and 10 p.m. on the 3 major networks were observed during a 7-day period in the spring of 1982. Statements related to attractiveness were…

Psychosocial Factors and Enrollment in a Televised Smoking Cessation Program.

ERIC Educational Resources Information Center

Kviz, Frederick J.; And Others

1991-01-01

Interviews with random samples of 641 registrants for a smoking cessation program on Chicago television news and 2,398 smokers who regularly viewed the news determined that registration was associated with (1) recognition of the need to change behavior; (2) high expectation for quitting; (3) concern about the burden of lung cancer on significant…

EDUCATIONAL TELEVISION IN THE SMALL SCHOOL.

ERIC Educational Resources Information Center

LEDFORD, LOWELL E.

HENSLEY ELEMENTARY SCHOOL, CONSISTING OF 72 STUDENTS AND 3 TEACHERS, HAS INCORPORATED 12 EDUCATIONAL TELEVISION PROGRAMS AS A REGULAR PART OF THE CURRICULUM IN THE FIRST 6 GRADES. GRADES 1 AND 2 VIEWED PROGRAMS IN SCIENCE, SPEECH, ART, MUSIC, AND STORY TIME. GRADES 3 AND 4 VIEWED SERIES IN MUSIC, SCIENCE, ART, AND SPEECH, WHILE GRADES 5 AND 6 WERE…

The 1984 ARI Survey of Army Recruits: Tabular Description of NPS (active) Army Accessions. Volume 1

DTIC Science & Technology

1986-05-01

WATCH TV PROG MJR LEAG BASEBALL PLAYOFFS 232-233 WATCH TV PROG WORLD SERIES 23<«-235 WATCH TV PROG NBA BASKETBALL 236-237 WATCH TV PROG COLLEGE...PROG:NBA BASKETBALL DO YOU ’^ATCH ANY OF THE FOLLOWING PROGRAMS OR PROGRAMMING TYPES ON TV? - NBA BASKETBALL , 1 - REGULARLY TURN ON THE TV TO WATCH...107. NBA basketball 108. College basketball 109. NHL hockey 110. Professional wrestling 111. Car r.ices 112. Golf tournaments 113. Tennis

[Changes in leisure activity among young people aged 15-18 years in Hungary: physical activity, media-consumption and smoking].

PubMed

Takács, Bence

2013-04-14

Young people are more and more inactive, which has numerous well-known negative effects on their health. Several studies indicate that inactive lifestyle disposes people to sit in front of the television, which increases aggression and decreases the willingness of reading. There is also a strong link between inactivity and an increase of body mass, deterioration of anthropometric parameters, and deviant behaviour. The aim of the study was to find out, on the basis of two cross-sectional surveys, the changes occurred within eight years in the free-time activity of Hungarian young people aged between 15 and 19 years. Data obtained from two surveys conducted by the National Institute for Family and Social Policy, Hungary in 2000 and 2008 including 1780 and 2018 young people, respectively, were analysed and compared. The number of young people regularly involved in sport activity increased significantly, while their media-consumption failed to decrease. Physically active young people are more health-conscious, but regular sporting activity did not expel smoking, which was associated with a sedentary lifestyle and television watching. These data reveal new responses of a new generation; watching television still takes the largest part of their free time activity, but use of computers, and participation in social activities are not necessarily increase sedentary lifestyle and deviant habits. Internet has positive effects on the regularity of their physical activity.

Hard-to-reach? Using health access status as a way to more effectively target segments of the Latino audience.

PubMed

Wilkin, Holley A; Ball-Rokeach, Sandra J

2011-04-01

Health issues disproportionately affect Latinos, but variations within this ethnic group may mean that some Latinos are harder to reach with health messages than others. This paper introduces a methodology grounded in communication infrastructure theory to better target 'hard-to-reach' audiences. A random digit dialing telephone survey of 739 Latinos living in two Los Angeles communities was conducted. The relationships between health access difficulties and connections to an integrated storytelling network as well as individual health communication source connections were explored. Findings suggest that Latinos who are connected to an integrated storytelling network report marginally greater ease finding healthcare, despite not being any more likely to have insurance or a regular place for healthcare. Latinos who have health access problems tended to rely more upon Spanish-language television for health information. In addition, those without healthcare access problems are more likely to indicate that they use health professionals, the Internet, mainstream TV and printed materials like health pamphlets for health information. The theoretical and methodological contributions of this work, its major findings, implications, limitations and policy guidelines are discussed.

An iterative algorithm for L1-TV constrained regularization in image restoration

NASA Astrophysics Data System (ADS)

Chen, K.; Loli Piccolomini, E.; Zama, F.

2015-11-01

We consider the problem of restoring blurred images affected by impulsive noise. The adopted method restores the images by solving a sequence of constrained minimization problems where the data fidelity function is the ℓ1 norm of the residual and the constraint, chosen as the image Total Variation, is automatically adapted to improve the quality of the restored images. Although this approach is general, we report here the case of vectorial images where the blurring model involves contributions from the different image channels (cross channel blur). A computationally convenient extension of the Total Variation function to vectorial images is used and the results reported show that this approach is efficient for recovering nearly optimal images.

TV watching, soap opera and happiness.

PubMed

Lu, L; Argyle, M

1993-09-01

One hundred and fourteen subjects reported the amount of time they spent watching television in general, and soap opera in particular. They also completed scales measuring happiness and other personality variables, such as extraversion and cooperativeness. In the multiple regression analysis, having controlled for the demographic variables, watching TV was related to unhappiness, whereas watching soap opera was related to happiness. Discriminant analysis showed that females, higher happiness and extraversion distinguished regular soap watchers (who nevertheless watched little TV in general) from irregular soap watchers (who nevertheless watched a lot of TV in general).

45 CFR 96.131 - Treatment services for pregnant women.

Code of Federal Regulations, 2013 CFR

2013-10-01

... (radio/television), regular advertisements in local/regional print media, posters placed in targeted... community based organizations, health care providers, and social service agencies. (c) The State shall in...

45 CFR 96.131 - Treatment services for pregnant women.

Code of Federal Regulations, 2014 CFR

2014-10-01

... (radio/television), regular advertisements in local/regional print media, posters placed in targeted... community based organizations, health care providers, and social service agencies. (c) The State shall in...

45 CFR 96.131 - Treatment services for pregnant women.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (radio/television), regular advertisements in local/regional print media, posters placed in targeted... community based organizations, health care providers, and social service agencies. (c) The State shall in...

45 CFR 96.131 - Treatment services for pregnant women.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (radio/television), regular advertisements in local/regional print media, posters placed in targeted... community based organizations, health care providers, and social service agencies. (c) The State shall in...

45 CFR 96.131 - Treatment services for pregnant women.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (radio/television), regular advertisements in local/regional print media, posters placed in targeted... community based organizations, health care providers, and social service agencies. (c) The State shall in...

Children's Television: An Analysis of Programming and Advertising.

ERIC Educational Resources Information Center

Barcus, F. Earle; Wolkin, Rachel

The studies reported in this book are content analyses of children's television and attendant advertising. Following an introductory statement, chapters present data about children's commercial television on the weekends, children's commercial television after school, and the seasonal variations in television advertising to children. A concluding…

36 CFR 705.1 - Scope and purpose of this part.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., COMPILATION, AND DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO... consisting of regularly scheduled newscasts or on-the-spot coverage of news events. ...

36 CFR 705.1 - Scope and purpose of this part.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., COMPILATION, AND DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO... consisting of regularly scheduled newscasts or on-the-spot coverage of news events. ...

36 CFR 705.1 - Scope and purpose of this part.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., COMPILATION, AND DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO... consisting of regularly scheduled newscasts or on-the-spot coverage of news events. ...

36 CFR 705.1 - Scope and purpose of this part.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., COMPILATION, AND DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO... consisting of regularly scheduled newscasts or on-the-spot coverage of news events. ...

36 CFR 705.2 - Authority.

Code of Federal Regulations, 2010 CFR

2010-07-01

... DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO ARCHIVES ACT § 705... program which consists of a regularly scheduled newscast or on-the-spot coverage of news events, to...

36 CFR § 705.1 - Scope and purpose of this part.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., COMPILATION, AND DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO... consisting of regularly scheduled newscasts or on-the-spot coverage of news events. ...

36 CFR 705.2 - Authority.

Code of Federal Regulations, 2011 CFR

2011-07-01

... DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO ARCHIVES ACT § 705... program which consists of a regularly scheduled newscast or on-the-spot coverage of news events, to...

36 CFR 705.2 - Authority.

Code of Federal Regulations, 2014 CFR

2014-07-01

... DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO ARCHIVES ACT § 705... program which consists of a regularly scheduled newscast or on-the-spot coverage of news events, to...

36 CFR 705.2 - Authority.

Code of Federal Regulations, 2012 CFR

2012-07-01

... DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO ARCHIVES ACT § 705... program which consists of a regularly scheduled newscast or on-the-spot coverage of news events, to...

Association between regular participation in sports and leisure time behaviors in Brazilian adolescents: a cross-sectional study.

PubMed

Fernandes, Rômulo Araújo; Júnior, Ismael Forte Freitas; Cardoso, Jefferson Rosa; Vaz Ronque, Enio Ricardo; Loch, Mathias Roberto; de Oliveira, Arli Ramos

2008-09-23

The belief that adolescents engaged in sports increase their overall physical activity level while simultaneously decreasing physical inactivity has been the foundation of many intervention programs in developing countries. The aim of this study was to analyze the association between regular participation in sports and both active behaviors and TV viewing during leisure time. A total of 1752 Brazilian adolescents (812 = male and 940 = female) participated in this study. Regular participation in sports, as well as active behaviors (exemplified by walking or cycling) and TV viewing during leisure time were assessed by means of a questionnaire. The chi-square test analyzed the association between sports practice and leisure time behaviors, and the Poisson regression with robust variance indicated the magnitude of these associations. The prevalence of regular participation in sports was 14.8% (95% confidence interval 13.2% to 16.5%). After adjustment for all confounders, participation in sports was associated with, at the highest frequency, cycling (PR = 2.55 [1.80-3.60]) and walking (PR = 2.69 [1.98-3.64]) during leisure time. However, there was not an association between the participation in sports and frequency of TV viewing (PR = 1.28 [0.81-2.02]). This study presented data indicating that the regular participation in sports is positively associated with a higher frequency of physically active behaviors during leisure time. However, the results did not support the hypothesis that the engagement in sports necessarily decreases leisure time spent in TV viewing.

36 CFR § 705.2 - Authority.

Code of Federal Regulations, 2013 CFR

2013-07-01

... DISTRIBUTION OF NEWS TRANSMISSIONS UNDER THE PROVISIONS OF THE AMERICAN TELEVISION AND RADIO ARCHIVES ACT § 705... program which consists of a regularly scheduled newscast or on-the-spot coverage of news events, to...

Integrating Mass Media Instruction: "Connecting" NIE and TV Programs for the 21st Century.

ERIC Educational Resources Information Center

Shapley, Barbara

More high school students watch television regularly than read newspapers. Newspapers in Education coordinators should be involved in teaching their students critical viewing skills. The essential concepts that students need to learn are to: (1) understand what mass media and popular culture mean; (2) understand how the media shape attitudes and…

s-SMOOTH: Sparsity and Smoothness Enhanced EEG Brain Tomography

PubMed Central

Li, Ying; Qin, Jing; Hsin, Yue-Loong; Osher, Stanley; Liu, Wentai

2016-01-01

EEG source imaging enables us to reconstruct current density in the brain from the electrical measurements with excellent temporal resolution (~ ms). The corresponding EEG inverse problem is an ill-posed one that has infinitely many solutions. This is due to the fact that the number of EEG sensors is usually much smaller than that of the potential dipole locations, as well as noise contamination in the recorded signals. To obtain a unique solution, regularizations can be incorporated to impose additional constraints on the solution. An appropriate choice of regularization is critically important for the reconstruction accuracy of a brain image. In this paper, we propose a novel Sparsity and SMOOthness enhanced brain TomograpHy (s-SMOOTH) method to improve the reconstruction accuracy by integrating two recently proposed regularization techniques: Total Generalized Variation (TGV) regularization and ℓ1−2 regularization. TGV is able to preserve the source edge and recover the spatial distribution of the source intensity with high accuracy. Compared to the relevant total variation (TV) regularization, TGV enhances the smoothness of the image and reduces staircasing artifacts. The traditional TGV defined on a 2D image has been widely used in the image processing field. In order to handle 3D EEG source images, we propose a voxel-based Total Generalized Variation (vTGV) regularization that extends the definition of second-order TGV from 2D planar images to 3D irregular surfaces such as cortex surface. In addition, the ℓ1−2 regularization is utilized to promote sparsity on the current density itself. We demonstrate that ℓ1−2 regularization is able to enhance sparsity and accelerate computations than ℓ1 regularization. The proposed model is solved by an efficient and robust algorithm based on the difference of convex functions algorithm (DCA) and the alternating direction method of multipliers (ADMM). Numerical experiments using synthetic data demonstrate the advantages of the proposed method over other state-of-the-art methods in terms of total reconstruction accuracy, localization accuracy and focalization degree. The application to the source localization of event-related potential data further demonstrates the performance of the proposed method in real-world scenarios. PMID:27965529

The 1984 ARI Survey of Army Recruits: Tabular Description of NPS (active) Army Accessions. Volume 2

DTIC Science & Technology

1986-05-01

YOU WATCH ANY OF THE FOLLOWING PROGRAMS OR PROGRAMMING TYPES ON TV? - NBA BASKETBALL 1 - REGULARLY TURN ON THE TV TO WATCH IT 2 - SOMETIMES WATCH IT...league baseball — regular season games 105. Major league baseball playoffs 106. World Series 107. NBA basketball 108. College basketball 109...LAG BASEBALL PLAYOFFS WORLD SERIES MBA BASKETBALL COLLEGE BASKETBALL NHL HOCKEY PROFESSIONAL WRESTLING CAR RACES 154 156 158- 160 162- 164

Combined Tensor Fitting and TV Regularization in Diffusion Tensor Imaging Based on a Riemannian Manifold Approach.

PubMed

Baust, Maximilian; Weinmann, Andreas; Wieczorek, Matthias; Lasser, Tobias; Storath, Martin; Navab, Nassir

2016-08-01

In this paper, we consider combined TV denoising and diffusion tensor fitting in DTI using the affine-invariant Riemannian metric on the space of diffusion tensors. Instead of first fitting the diffusion tensors, and then denoising them, we define a suitable TV type energy functional which incorporates the measured DWIs (using an inverse problem setup) and which measures the nearness of neighboring tensors in the manifold. To approach this functional, we propose generalized forward- backward splitting algorithms which combine an explicit and several implicit steps performed on a decomposition of the functional. We validate the performance of the derived algorithms on synthetic and real DTI data. In particular, we work on real 3D data. To our knowledge, the present paper describes the first approach to TV regularization in a combined manifold and inverse problem setup.

Convex composite wavelet frame and total variation-based image deblurring using nonconvex penalty functions

NASA Astrophysics Data System (ADS)

Shen, Zhengwei; Cheng, Lishuang

2017-09-01

Total variation (TV)-based image deblurring method can bring on staircase artifacts in the homogenous region of the latent images recovered from the degraded images while a wavelet/frame-based image deblurring method will lead to spurious noise spikes and pseudo-Gibbs artifacts in the vicinity of discontinuities of the latent images. To suppress these artifacts efficiently, we propose a nonconvex composite wavelet/frame and TV-based image deblurring model. In this model, the wavelet/frame and the TV-based methods may complement each other, which are verified by theoretical analysis and experimental results. To further improve the quality of the latent images, nonconvex penalty function is used to be the regularization terms of the model, which may induce a stronger sparse solution and will more accurately estimate the relative large gradient or wavelet/frame coefficients of the latent images. In addition, by choosing a suitable parameter to the nonconvex penalty function, the subproblem that splits by the alternative direction method of multipliers algorithm from the proposed model can be guaranteed to be a convex optimization problem; hence, each subproblem can converge to a global optimum. The mean doubly augmented Lagrangian and the isotropic split Bregman algorithms are used to solve these convex subproblems where the designed proximal operator is used to reduce the computational complexity of the algorithms. Extensive numerical experiments indicate that the proposed model and algorithms are comparable to other state-of-the-art model and methods.

Blind motion image deblurring using nonconvex higher-order total variation model

NASA Astrophysics Data System (ADS)

Li, Weihong; Chen, Rui; Xu, Shangwen; Gong, Weiguo

2016-09-01

We propose a nonconvex higher-order total variation (TV) method for blind motion image deblurring. First, we introduce a nonconvex higher-order TV differential operator to define a new model of the blind motion image deblurring, which can effectively eliminate the staircase effect of the deblurred image; meanwhile, we employ an image sparse prior to improve the edge recovery quality. Second, to improve the accuracy of the estimated motion blur kernel, we use L1 norm and H1 norm as the blur kernel regularization term, considering the sparsity and smoothing of the motion blur kernel. Third, because it is difficult to solve the numerically computational complexity problem of the proposed model owing to the intrinsic nonconvexity, we propose a binary iterative strategy, which incorporates a reweighted minimization approximating scheme in the outer iteration, and a split Bregman algorithm in the inner iteration. And we also discuss the convergence of the proposed binary iterative strategy. Last, we conduct extensive experiments on both synthetic and real-world degraded images. The results demonstrate that the proposed method outperforms the previous representative methods in both quality of visual perception and quantitative measurement.

Evaluation of hybrid SART  +  OS  +  TV iterative reconstruction algorithm for optical-CT gel dosimeter imaging

NASA Astrophysics Data System (ADS)

Du, Yi; Wang, Xiangang; Xiang, Xincheng; Wei, Zhouping

2016-12-01

Optical computed tomography (optical-CT) is a high-resolution, fast, and easily accessible readout modality for gel dosimeters. This paper evaluates a hybrid iterative image reconstruction algorithm for optical-CT gel dosimeter imaging, namely, the simultaneous algebraic reconstruction technique (SART) integrated with ordered subsets (OS) iteration and total variation (TV) minimization regularization. The mathematical theory and implementation workflow of the algorithm are detailed. Experiments on two different optical-CT scanners were performed for cross-platform validation. For algorithm evaluation, the iterative convergence is first shown, and peak-to-noise-ratio (PNR) and contrast-to-noise ratio (CNR) results are given with the cone-beam filtered backprojection (FDK) algorithm and the FDK results followed by median filtering (mFDK) as reference. The effect on spatial gradients and reconstruction artefacts is also investigated. The PNR curve illustrates that the results of SART  +  OS  +  TV finally converges to that of FDK but with less noise, which implies that the dose-OD calibration method for FDK is also applicable to the proposed algorithm. The CNR in selected regions-of-interest (ROIs) of SART  +  OS  +  TV results is almost double that of FDK and 50% higher than that of mFDK. The artefacts in SART  +  OS  +  TV results are still visible, but have been much suppressed with little spatial gradient loss. Based on the assessment, we can conclude that this hybrid SART  +  OS  +  TV algorithm outperforms both FDK and mFDK in denoising, preserving spatial dose gradients and reducing artefacts, and its effectiveness and efficiency are platform independent.

A Model of Regularization Parameter Determination in Low-Dose X-Ray CT Reconstruction Based on Dictionary Learning.

PubMed

Zhang, Cheng; Zhang, Tao; Zheng, Jian; Li, Ming; Lu, Yanfei; You, Jiali; Guan, Yihui

2015-01-01

In recent years, X-ray computed tomography (CT) is becoming widely used to reveal patient's anatomical information. However, the side effect of radiation, relating to genetic or cancerous diseases, has caused great public concern. The problem is how to minimize radiation dose significantly while maintaining image quality. As a practical application of compressed sensing theory, one category of methods takes total variation (TV) minimization as the sparse constraint, which makes it possible and effective to get a reconstruction image of high quality in the undersampling situation. On the other hand, a preliminary attempt of low-dose CT reconstruction based on dictionary learning seems to be another effective choice. But some critical parameters, such as the regularization parameter, cannot be determined by detecting datasets. In this paper, we propose a reweighted objective function that contributes to a numerical calculation model of the regularization parameter. A number of experiments demonstrate that this strategy performs well with better reconstruction images and saving of a large amount of time.

Developing English and Spanish television public service announcements to promote colorectal cancer screening.

PubMed

Cooper, Crystale Purvis; Gelb, Cynthia A; Jameson, Heather; Macario, Everly; Jorgensen, Cynthia M; Seeff, Laura

2005-10-01

Screen for Life: National Colorectal Cancer Action Campaign (SFL) is a federally funded campaign to promote understanding of colorectal cancer and the importance of regular screening for adults aged 50 years and older. SFL uses a variety of communication strategies, including television public service announcements (PSAs). SFL materials are developed using the Health Communication Process endorsed by the U.S. Department of Health and Human Services, which has four stages: (a) planning and strategy development; (b) developing and pretesting concepts, messages, and materials; (c) implementing the program; and (d) assessing effectiveness and making refinements. This article describes SFL's application of this process to develop television PSAs in English and Spanish.

Dialectical Features of Black Characters in Situation Comedies on Television.

ERIC Educational Resources Information Center

Fine, Marlene G.; Anderson, Carolyn

1980-01-01

Three prime time television situation comedies with primarily Black casts were studied for frequency and variations in use of Black English Vernacular (BEV). It is suggested that homogenization of BEV on American television reflects the attitude that BEV is not a legitimate language choice. (GC)

Evaluation of the OSC-TV iterative reconstruction algorithm for cone-beam optical CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matenine, Dmitri, E-mail: dmitri.matenine.1@ulaval.ca; Mascolo-Fortin, Julia, E-mail: julia.mascolo-fortin.1@ulaval.ca; Goussard, Yves, E-mail: yves.goussard@polymtl.ca

Purpose: The present work evaluates an iterative reconstruction approach, namely, the ordered subsets convex (OSC) algorithm with regularization via total variation (TV) minimization in the field of cone-beam optical computed tomography (optical CT). One of the uses of optical CT is gel-based 3D dosimetry for radiation therapy, where it is employed to map dose distributions in radiosensitive gels. Model-based iterative reconstruction may improve optical CT image quality and contribute to a wider use of optical CT in clinical gel dosimetry. Methods: This algorithm was evaluated using experimental data acquired by a cone-beam optical CT system, as well as complementary numericalmore » simulations. A fast GPU implementation of OSC-TV was used to achieve reconstruction times comparable to those of conventional filtered backprojection. Images obtained via OSC-TV were compared with the corresponding filtered backprojections. Spatial resolution and uniformity phantoms were scanned and respective reconstructions were subject to evaluation of the modulation transfer function, image uniformity, and accuracy. The artifacts due to refraction and total signal loss from opaque objects were also studied. Results: The cone-beam optical CT data reconstructions showed that OSC-TV outperforms filtered backprojection in terms of image quality, thanks to a model-based simulation of the photon attenuation process. It was shown to significantly improve the image spatial resolution and reduce image noise. The accuracy of the estimation of linear attenuation coefficients remained similar to that obtained via filtered backprojection. Certain image artifacts due to opaque objects were reduced. Nevertheless, the common artifact due to the gel container walls could not be eliminated. Conclusions: The use of iterative reconstruction improves cone-beam optical CT image quality in many ways. The comparisons between OSC-TV and filtered backprojection presented in this paper demonstrate that OSC-TV can potentially improve the rendering of spatial features and reduce cone-beam optical CT artifacts.« less

Evaluation of the OSC-TV iterative reconstruction algorithm for cone-beam optical CT.

PubMed

Matenine, Dmitri; Mascolo-Fortin, Julia; Goussard, Yves; Després, Philippe

2015-11-01

The present work evaluates an iterative reconstruction approach, namely, the ordered subsets convex (OSC) algorithm with regularization via total variation (TV) minimization in the field of cone-beam optical computed tomography (optical CT). One of the uses of optical CT is gel-based 3D dosimetry for radiation therapy, where it is employed to map dose distributions in radiosensitive gels. Model-based iterative reconstruction may improve optical CT image quality and contribute to a wider use of optical CT in clinical gel dosimetry. This algorithm was evaluated using experimental data acquired by a cone-beam optical CT system, as well as complementary numerical simulations. A fast GPU implementation of OSC-TV was used to achieve reconstruction times comparable to those of conventional filtered backprojection. Images obtained via OSC-TV were compared with the corresponding filtered backprojections. Spatial resolution and uniformity phantoms were scanned and respective reconstructions were subject to evaluation of the modulation transfer function, image uniformity, and accuracy. The artifacts due to refraction and total signal loss from opaque objects were also studied. The cone-beam optical CT data reconstructions showed that OSC-TV outperforms filtered backprojection in terms of image quality, thanks to a model-based simulation of the photon attenuation process. It was shown to significantly improve the image spatial resolution and reduce image noise. The accuracy of the estimation of linear attenuation coefficients remained similar to that obtained via filtered backprojection. Certain image artifacts due to opaque objects were reduced. Nevertheless, the common artifact due to the gel container walls could not be eliminated. The use of iterative reconstruction improves cone-beam optical CT image quality in many ways. The comparisons between OSC-TV and filtered backprojection presented in this paper demonstrate that OSC-TV can potentially improve the rendering of spatial features and reduce cone-beam optical CT artifacts.

32 CFR 705.7 - Radio and television.

Code of Federal Regulations, 2014 CFR

2014-07-01

... extra expense involved. A strict accounting of the additional expenses incurred and charged to the production company must be maintained by the designated project officer. A copy of this accounting will be...) Not in competition with the regular employment of professional performers. (2) The public affairs...

32 CFR 705.7 - Radio and television.

Code of Federal Regulations, 2013 CFR

2013-07-01

... extra expense involved. A strict accounting of the additional expenses incurred and charged to the production company must be maintained by the designated project officer. A copy of this accounting will be...) Not in competition with the regular employment of professional performers. (2) The public affairs...

Linear functional minimization for inverse modeling

DOE PAGES

Barajas-Solano, David A.; Wohlberg, Brendt Egon; Vesselinov, Velimir Valentinov; ...

2015-06-01

In this paper, we present a novel inverse modeling strategy to estimate spatially distributed parameters of nonlinear models. The maximum a posteriori (MAP) estimators of these parameters are based on a likelihood functional, which contains spatially discrete measurements of the system parameters and spatiotemporally discrete measurements of the transient system states. The piecewise continuity prior for the parameters is expressed via Total Variation (TV) regularization. The MAP estimator is computed by minimizing a nonquadratic objective equipped with the TV operator. We apply this inversion algorithm to estimate hydraulic conductivity of a synthetic confined aquifer from measurements of conductivity and hydraulicmore » head. The synthetic conductivity field is composed of a low-conductivity heterogeneous intrusion into a high-conductivity heterogeneous medium. Our algorithm accurately reconstructs the location, orientation, and extent of the intrusion from the steady-state data only. Finally, addition of transient measurements of hydraulic head improves the parameter estimation, accurately reconstructing the conductivity field in the vicinity of observation locations.« less

Associations between watching TV during family meals and dietary intake among adolescents.

PubMed

Feldman, Shira; Eisenberg, Marla E; Neumark-Sztainer, Dianne; Story, Mary

2007-01-01

To examine associations between watching television during family meals and dietary intake among adolescents. Cross-sectional study using survey data from a diverse sample of adolescents. Data were collected from a school-based survey during the 1998-1999 school year. Middle and high school students (N = 4746) from 31 public schools in the Minneapolis-St. Paul area. Response rate was 81.5%. Intake of fruits, total vegetables, dark green/yellow vegetables, calcium-rich food, grains, soft drinks, fried food, snack food, calories, family meal frequency, and watching television during meals. General linear modeling comparing dietary intake across 3 groups. 33.5% of boys and 30.9% of girls reported watching television during family meals. Adolescents watching television were found to have lower intakes of vegetables, dark green/yellow vegetables, calcium-rich food, and grains and higher intakes of soft drinks compared to adolescents not watching television during meals. However, watching television during family meals was associated with a more healthful diet than not eating regular family meals. Watching television during family meals was associated with poorer dietary quality among adolescents. Health care providers should work with families and adolescents to promote family meals, emphasizing turning the TV off at meals.

The Right Tools for the Right Jobs.

ERIC Educational Resources Information Center

Barbalich, Andrea, Ed.

1995-01-01

A chart shows the best campus public relations uses for 17 communication techniques: face-to-face contact; phone call, regular mail; electronic mail; special events; a speech; press release; press kit; press conference; television and radio public service announcements; video news releases; promotions and posters; advertising; newsletter;…

Comparison of Weather Shows in Eastern Europe

NASA Astrophysics Data System (ADS)

Najman, M.

2009-09-01

Comparison of Weather Shows in Eastern Europe Television weather shows in Eastern Europe have in most cases in the high graphical standard. There is though a wast difference in duration and information content in the weather shows. There are few signs and regularities by which we can see the character of the weather show. The main differences are mainly caused by the income structure of the TV station. Either it is a fully privately funded TV relying on the TV commercials income. Or it is a public service TV station funded mainly by the national budget or fixed fee structure/tax. There are wast differences in duration and even a graphical presentation of the weather. Next important aspect is a supplier of the weather information and /or the processor. Shortly we can say, that when the TV show is produced by the national met office, the TV show consists of more scientific terms, synoptic maps, satellite imagery, etc. If the supplier is the private meteorological company, the weather show is more user-friendly, laical with less scientific terms. We are experiencing a massive shift in public weather knowledge and demand for information. In the past, weather shows consisted only of maps with weather icons. In todaýs world, even the laic weather shows consist partly of numerical weather model outputs - they are of course designed to be understandable and graphically attractive. Outputs of the numerical weather models used to be only a part of daily life of a professional meteorologist, today they are common part of life of regular people. Video samples are a part of this presentation.

SU-G-BRA-11: Tumor Tracking in An Iterative Volume of Interest Based 4D CBCT Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, R; Pan, T; Ahmad, M

2016-06-15

Purpose: 4D CBCT can allow evaluation of tumor motion immediately prior to radiation therapy, but suffers from heavy artifacts that limit its ability to track tumors. Various iterative and compressed sensing reconstructions have been proposed to reduce these artifacts, but are costly time-wise and can degrade the image quality of bony anatomy for alignment with regularization. We have previously proposed an iterative volume of interest (I4D VOI) method which minimizes reconstruction time and maintains image quality of bony anatomy by focusing a 4D reconstruction within a VOI. The purpose of this study is to test the tumor tracking accuracy ofmore » this method compared to existing methods. Methods: Long scan (8–10 mins) CBCT data with corresponding RPM data was collected for 12 lung cancer patients. The full data set was sorted into 8 phases and reconstructed using FDK cone beam reconstruction to serve as a gold standard. The data was reduced in way that maintains a normal breathing pattern and used to reconstruct 4D images using FDK, low and high regularization TV minimization (λ=2,10), and the proposed I4D VOI method with PTVs used for the VOI. Tumor trajectories were found using rigid registration within the VOI for each reconstruction and compared to the gold standard. Results: The root mean square error (RMSE) values were 2.70mm for FDK, 2.50mm for low regularization TV, 1.48mm for high regularization TV, and 2.34mm for I4D VOI. Streak artifacts in I4D VOI were reduced compared to FDK and images were less blurred than TV reconstructed images. Conclusion: I4D VOI performed at least as well as existing methods in tumor tracking, with the exception of high regularization TV minimization. These results along with the reconstruction time and outside VOI image quality advantages suggest I4D VOI to be an improvement over existing methods. Funding support provided by CPRIT grant RP110562-P2-01.« less

Bias correction for magnetic resonance images via joint entropy regularization.

PubMed

Wang, Shanshan; Xia, Yong; Dong, Pei; Luo, Jianhua; Huang, Qiu; Feng, Dagan; Li, Yuanxiang

2014-01-01

Due to the imperfections of the radio frequency (RF) coil or object-dependent electrodynamic interactions, magnetic resonance (MR) images often suffer from a smooth and biologically meaningless bias field, which causes severe troubles for subsequent processing and quantitative analysis. To effectively restore the original signal, this paper simultaneously exploits the spatial and gradient features of the corrupted MR images for bias correction via the joint entropy regularization. With both isotropic and anisotropic total variation (TV) considered, two nonparametric bias correction algorithms have been proposed, namely IsoTVBiasC and AniTVBiasC. These two methods have been applied to simulated images under various noise levels and bias field corruption and also tested on real MR data. The test results show that the proposed two methods can effectively remove the bias field and also present comparable performance compared to the state-of-the-art methods.

Color TV: total variation methods for restoration of vector-valued images.

PubMed

Blomgren, P; Chan, T F

1998-01-01

We propose a new definition of the total variation (TV) norm for vector-valued functions that can be applied to restore color and other vector-valued images. The new TV norm has the desirable properties of 1) not penalizing discontinuities (edges) in the image, 2) being rotationally invariant in the image space, and 3) reducing to the usual TV norm in the scalar case. Some numerical experiments on denoising simple color images in red-green-blue (RGB) color space are presented.

Generalized Scalar-on-Image Regression Models via Total Variation.

PubMed

Wang, Xiao; Zhu, Hongtu

2017-01-01

The use of imaging markers to predict clinical outcomes can have a great impact in public health. The aim of this paper is to develop a class of generalized scalar-on-image regression models via total variation (GSIRM-TV), in the sense of generalized linear models, for scalar response and imaging predictor with the presence of scalar covariates. A key novelty of GSIRM-TV is that it is assumed that the slope function (or image) of GSIRM-TV belongs to the space of bounded total variation in order to explicitly account for the piecewise smooth nature of most imaging data. We develop an efficient penalized total variation optimization to estimate the unknown slope function and other parameters. We also establish nonasymptotic error bounds on the excess risk. These bounds are explicitly specified in terms of sample size, image size, and image smoothness. Our simulations demonstrate a superior performance of GSIRM-TV against many existing approaches. We apply GSIRM-TV to the analysis of hippocampus data obtained from the Alzheimers Disease Neuroimaging Initiative (ADNI) dataset.

Confronting Ambiguity in Science

ERIC Educational Resources Information Center

Emery, Katherine; Harlow, Danielle; Whitmer, Ali; Gaines, Steven

2015-01-01

People are regularly confronted with environmental and science-related issues presented to them in newspapers, on television, or even in their own doctor's office. Often the information they use to inform their decisions on matters of science may be ambiguous and contradictory. This article presents an activity that investigates how students deal…

Consumption of sugar-rich food products among Brazilian students:National School Health Survey (PeNSE 2012).

PubMed

Ferreira, Nathália Luíza; Claro, Rafael Moreira; Lopes, Aline Cristine Souza

2015-12-01

This study aimed to analyze the consumption of high-sugar foods by Brazilian schoolchildren and to identify associated factors, based on data from the National School Health Survey (PeNSE 2012). Consumption of these foods was classified as: do not consume sweets and soft drinks regularly; consume sweets or soft drinks regularly; and consume sweets and soft drinks regularly. Its association with sociodemographic information, eating habits, and family contexts were investigated via multiple ordinal regressions. Regular consumption of sweets and/or soft drinks was reported by 19.2% and 36.1% of adolescents, respectively, and higher prevalence was associated with female gender, age 14-15 years, higher maternal education, not living with the mother and father, not eating meals with the parents, eating while watching TV, and longer TV time. Nearly one-fifth of adolescents regularly consumed sweets and soft drinks, which was associated with socio-demographic and behavioral factors that should be targeted in order to improve their food consumption.

SU-F-18C-13: Low-Dose X-Ray CT Reconstruction Using a Hybrid First-Order Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, L; Lin, W; Jin, M

2014-06-15

Purpose: To develop a novel reconstruction method for X-ray CT that can lead to accurate reconstruction at significantly reduced dose levels combining low X-ray incident intensity and few views of projection data. Methods: The noise nature of the projection data at low X-ray incident intensity was modeled and accounted by the weighted least-squares (WLS) criterion. The total variation (TV) penalty was used to mitigate artifacts caused by few views of data. The first order primal-dual (FOPD) algorithm was used to minimize TV in image domain, which avoided the difficulty of the non-smooth objective function. The TV penalized WLS reconstruction wasmore » achieved by alternated FOPD TV minimization and projection onto convex sets (POCS) for data fidelity constraints. The proposed FOPD-POCS method was evaluated using the FORBILD jaw phantom and the real cadaver head CT data. Results: The quantitative measures, root mean square error (RMSE) and contrast-to-noise ratio (CNR), demonstrate the superior denoising capability of WLS over LS-based TV iterative reconstruction. The improvement of RMSE (WLS vs. LS) is 15%∼21% and that of CNR is 17%∼72% when the incident counts per ray are ranged from 1×10{sup 5} to 1×10{sup 3}. In addition, the TV regularization can accurately reconstruct images from about 50 views of the jaw phantom. The FOPD-POCS reconstruction reveals more structural details and suffers fewer artifacts in both the phantom and real head images. The FOPD-POCS method also shows fast convergence at low X-ray incident intensity. Conclusion: The new hybrid FOPD-POCS method, based on TV penalized WLS, yields excellent image quality when the incident X-ray intensity is low and the projection views are limited. The reconstruction is computationally efficient since the FOPD minimization of TV is applied only in the image domain. The characteristics of FOPD-POCS can be exploited to significantly reduce radiation dose of X-ray CT without compromising accuracy for diagnosis or treatment planning.« less

Superiorized algorithm for reconstruction of CT images from sparse-view and limited-angle polyenergetic data

NASA Astrophysics Data System (ADS)

Humphries, T.; Winn, J.; Faridani, A.

2017-08-01

Recent work in CT image reconstruction has seen increasing interest in the use of total variation (TV) and related penalties to regularize problems involving reconstruction from undersampled or incomplete data. Superiorization is a recently proposed heuristic which provides an automatic procedure to ‘superiorize’ an iterative image reconstruction algorithm with respect to a chosen objective function, such as TV. Under certain conditions, the superiorized algorithm is guaranteed to find a solution that is as satisfactory as any found by the original algorithm with respect to satisfying the constraints of the problem; this solution is also expected to be superior with respect to the chosen objective. Most work on superiorization has used reconstruction algorithms which assume a linear measurement model, which in the case of CT corresponds to data generated from a monoenergetic x-ray beam. Many CT systems generate x-rays from a polyenergetic spectrum, however, in which the measured data represent an integral of object attenuation over all energies in the spectrum. This inconsistency with the linear model produces the well-known beam hardening artifacts, which impair analysis of CT images. In this work we superiorize an iterative algorithm for reconstruction from polyenergetic data, using both TV and an anisotropic TV (ATV) penalty. We apply the superiorized algorithm in numerical phantom experiments modeling both sparse-view and limited-angle scenarios. In our experiments, the superiorized algorithm successfully finds solutions which are as constraints-compatible as those found by the original algorithm, with significantly reduced TV and ATV values. The superiorized algorithm thus produces images with greatly reduced sparse-view and limited angle artifacts, which are also largely free of the beam hardening artifacts that would be present if a superiorized version of a monoenergetic algorithm were used.

Nonlinear PP and PS joint inversion based on the exact Zoeppritz equations: a two-stage procedure

NASA Astrophysics Data System (ADS)

Zhi, Lixia; Chen, Shuangquan; Song, Baoshan; Li, Xiang-yang

2018-04-01

S-velocity and density are very important parameters in distinguishing lithology and estimating other petrophysical properties. A reliable estimate of S-velocity and density is very difficult to obtain, even from long-offset gather data. Joint inversion of PP and PS data provides a promising strategy for stabilizing and improving the results of inversion in estimating elastic parameters and density. For 2D or 3D inversion, the trace-by-trace strategy is still the most widely used method although it often suffers from a lack of clarity because of its high efficiency, which is due to parallel computing. This paper describes a two-stage inversion method for nonlinear PP and PS joint inversion based on the exact Zoeppritz equations. There are several advantages for our proposed methods as follows: (1) Thanks to the exact Zoeppritz equation, our joint inversion method is applicable for wide angle amplitude-versus-angle inversion; (2) The use of both P- and S-wave information can further enhance the stability and accuracy of parameter estimation, especially for the S-velocity and density; (3) The two-stage inversion procedure proposed in this paper can achieve a good compromise between efficiency and precision. On the one hand, the trace-by-trace strategy used in the first stage can be processed in parallel so that it has high computational efficiency. On the other hand, to deal with the indistinctness of and undesired disturbances to the inversion results obtained from the first stage, we apply the second stage—total variation (TV) regularization. By enforcing spatial and temporal constraints, the TV regularization stage deblurs the inversion results and leads to parameter estimation with greater precision. Notably, the computation consumption of the TV regularization stage can be ignored compared to the first stage because it is solved using the fast split Bregman iterations. Numerical examples using a well log and the Marmousi II model show that the proposed joint inversion is a reliable method capable of accurately estimating the density parameter as well as P-wave velocity and S-wave velocity, even when the seismic data is noisy with signal-to-noise ratio of 5.

Childhood and Adolescent Television Viewing and Antisocial Behavior in Early Adulthood

PubMed Central

Robertson, Lindsay A.; McAnally, Helena M.

2013-01-01

OBJECTIVE: To investigate whether excessive television viewing throughout childhood and adolescence is associated with increased antisocial behavior in early adulthood. METHODS: We assessed a birth cohort of 1037 individuals born in Dunedin, New Zealand, in 1972–1973, at regular intervals from birth to age 26 years. We used regression analysis to investigate the associations between television viewing hours from ages 5 to 15 years and criminal convictions, violent convictions, diagnosis of antisocial personality disorder, and aggressive personality traits in early adulthood. RESULTS: Young adults who had spent more time watching television during childhood and adolescence were significantly more likely to have a criminal conviction, a diagnosis of antisocial personality disorder, and more aggressive personality traits compared with those who viewed less television. The associations were statistically significant after controlling for sex IQ, socioeconomic status, previous antisocial behavior, and parental control. The associations were similar for both sexes, indicating that the relationship between television viewing and antisocial behavior is similar for male and female viewers. CONCLUSIONS: Excessive television viewing in childhood and adolescence is associated with increased antisocial behavior in early adulthood. The findings are consistent with a causal association and support the American Academy of Pediatrics recommendation that children should watch no more than 1 to 2 hours of television each day. PMID:23420910

A Model of Regularization Parameter Determination in Low-Dose X-Ray CT Reconstruction Based on Dictionary Learning

PubMed Central

Zhang, Cheng; Zhang, Tao; Li, Ming; Lu, Yanfei; You, Jiali; Guan, Yihui

2015-01-01

In recent years, X-ray computed tomography (CT) is becoming widely used to reveal patient's anatomical information. However, the side effect of radiation, relating to genetic or cancerous diseases, has caused great public concern. The problem is how to minimize radiation dose significantly while maintaining image quality. As a practical application of compressed sensing theory, one category of methods takes total variation (TV) minimization as the sparse constraint, which makes it possible and effective to get a reconstruction image of high quality in the undersampling situation. On the other hand, a preliminary attempt of low-dose CT reconstruction based on dictionary learning seems to be another effective choice. But some critical parameters, such as the regularization parameter, cannot be determined by detecting datasets. In this paper, we propose a reweighted objective function that contributes to a numerical calculation model of the regularization parameter. A number of experiments demonstrate that this strategy performs well with better reconstruction images and saving of a large amount of time. PMID:26550024

"Soccer": The Beautiful Game

ERIC Educational Resources Information Center

Spires, Todd

2008-01-01

Soccer, or football as it is called in the rest of the world, is the most popular and fastest-growing global sport, with an estimated 240 million people regularly playing what Brazilian star Pele called "the beautiful game." Millions, worldwide, watch it on television. In 2006, the average viewership for each match of the month-long World Cup was…

Minimize Subjective Theory, Maximize Authentic Experience in the Teaching of French Civilization.

ERIC Educational Resources Information Center

Corredor, Eva L.

A program developed to teach French civilization and modern France at the U.S. Naval Academy (Annapolis, Maryland) was designed to take advantage of readily available, relatively sophisticated technology for classroom instruction. The hardware used includes a satellite earth station that receives regular television broadcasts from France, a…

Towards adjoint-based inversion for rheological parameters in nonlinear viscous mantle flow

NASA Astrophysics Data System (ADS)

Worthen, Jennifer; Stadler, Georg; Petra, Noemi; Gurnis, Michael; Ghattas, Omar

2014-09-01

We address the problem of inferring mantle rheological parameter fields from surface velocity observations and instantaneous nonlinear mantle flow models. We formulate this inverse problem as an infinite-dimensional nonlinear least squares optimization problem governed by nonlinear Stokes equations. We provide expressions for the gradient of the cost functional of this optimization problem with respect to two spatially-varying rheological parameter fields: the viscosity prefactor and the exponent of the second invariant of the strain rate tensor. Adjoint (linearized) Stokes equations, which are characterized by a 4th order anisotropic viscosity tensor, facilitates efficient computation of the gradient. A quasi-Newton method for the solution of this optimization problem is presented, which requires the repeated solution of both nonlinear forward Stokes and linearized adjoint Stokes equations. For the solution of the nonlinear Stokes equations, we find that Newton’s method is significantly more efficient than a Picard fixed point method. Spectral analysis of the inverse operator given by the Hessian of the optimization problem reveals that the numerical eigenvalues collapse rapidly to zero, suggesting a high degree of ill-posedness of the inverse problem. To overcome this ill-posedness, we employ Tikhonov regularization (favoring smooth parameter fields) or total variation (TV) regularization (favoring piecewise-smooth parameter fields). Solution of two- and three-dimensional finite element-based model inverse problems show that a constant parameter in the constitutive law can be recovered well from surface velocity observations. Inverting for a spatially-varying parameter field leads to its reasonable recovery, in particular close to the surface. When inferring two spatially varying parameter fields, only an effective viscosity field and the total viscous dissipation are recoverable. Finally, a model of a subducting plate shows that a localized weak zone at the plate boundary can be partially recovered, especially with TV regularization.

Simultaneous deblurring and iterative reconstruction of CBCT for image guided brain radiosurgery.

PubMed

Hashemi, SayedMasoud; Song, William Y; Sahgal, Arjun; Lee, Young; Huynh, Christopher; Grouza, Vladimir; Nordström, Håkan; Eriksson, Markus; Dorenlot, Antoine; Régis, Jean Marie; Mainprize, James G; Ruschin, Mark

2017-04-07

One of the limiting factors in cone-beam CT (CBCT) image quality is system blur, caused by detector response, x-ray source focal spot size, azimuthal blurring, and reconstruction algorithm. In this work, we develop a novel iterative reconstruction algorithm that improves spatial resolution by explicitly accounting for image unsharpness caused by different factors in the reconstruction formulation. While the model-based iterative reconstruction techniques use prior information about the detector response and x-ray source, our proposed technique uses a simple measurable blurring model. In our reconstruction algorithm, denoted as simultaneous deblurring and iterative reconstruction (SDIR), the blur kernel can be estimated using the modulation transfer function (MTF) slice of the CatPhan phantom or any other MTF phantom, such as wire phantoms. The proposed image reconstruction formulation includes two regularization terms: (1) total variation (TV) and (2) nonlocal regularization, solved with a split Bregman augmented Lagrangian iterative method. The SDIR formulation preserves edges, eases the parameter adjustments to achieve both high spatial resolution and low noise variances, and reduces the staircase effect caused by regular TV-penalized iterative algorithms. The proposed algorithm is optimized for a point-of-care head CBCT unit for image-guided radiosurgery and is tested with CatPhan phantom, an anthropomorphic head phantom, and 6 clinical brain stereotactic radiosurgery cases. Our experiments indicate that SDIR outperforms the conventional filtered back projection and TV penalized simultaneous algebraic reconstruction technique methods (represented by adaptive steepest-descent POCS algorithm, ASD-POCS) in terms of MTF and line pair resolution, and retains the favorable properties of the standard TV-based iterative reconstruction algorithms in improving the contrast and reducing the reconstruction artifacts. It improves the visibility of the high contrast details in bony areas and the brain soft-tissue. For example, the results show the ventricles and some brain folds become visible in SDIR reconstructed images and the contrast of the visible lesions is effectively improved. The line-pair resolution was improved from 12 line-pair/cm in FBP to 14 line-pair/cm in SDIR. Adjusting the parameters of the ASD-POCS to achieve 14 line-pair/cm caused the noise variance to be higher than the SDIR. Using these parameters for ASD-POCS, the MTF of FBP and ASD-POCS were very close and equal to 0.7 mm -1 which was increased to 1.2 mm -1 by SDIR, at half maximum.

Simultaneous deblurring and iterative reconstruction of CBCT for image guided brain radiosurgery

NASA Astrophysics Data System (ADS)

Hashemi, SayedMasoud; Song, William Y.; Sahgal, Arjun; Lee, Young; Huynh, Christopher; Grouza, Vladimir; Nordström, Håkan; Eriksson, Markus; Dorenlot, Antoine; Régis, Jean Marie; Mainprize, James G.; Ruschin, Mark

2017-04-01

One of the limiting factors in cone-beam CT (CBCT) image quality is system blur, caused by detector response, x-ray source focal spot size, azimuthal blurring, and reconstruction algorithm. In this work, we develop a novel iterative reconstruction algorithm that improves spatial resolution by explicitly accounting for image unsharpness caused by different factors in the reconstruction formulation. While the model-based iterative reconstruction techniques use prior information about the detector response and x-ray source, our proposed technique uses a simple measurable blurring model. In our reconstruction algorithm, denoted as simultaneous deblurring and iterative reconstruction (SDIR), the blur kernel can be estimated using the modulation transfer function (MTF) slice of the CatPhan phantom or any other MTF phantom, such as wire phantoms. The proposed image reconstruction formulation includes two regularization terms: (1) total variation (TV) and (2) nonlocal regularization, solved with a split Bregman augmented Lagrangian iterative method. The SDIR formulation preserves edges, eases the parameter adjustments to achieve both high spatial resolution and low noise variances, and reduces the staircase effect caused by regular TV-penalized iterative algorithms. The proposed algorithm is optimized for a point-of-care head CBCT unit for image-guided radiosurgery and is tested with CatPhan phantom, an anthropomorphic head phantom, and 6 clinical brain stereotactic radiosurgery cases. Our experiments indicate that SDIR outperforms the conventional filtered back projection and TV penalized simultaneous algebraic reconstruction technique methods (represented by adaptive steepest-descent POCS algorithm, ASD-POCS) in terms of MTF and line pair resolution, and retains the favorable properties of the standard TV-based iterative reconstruction algorithms in improving the contrast and reducing the reconstruction artifacts. It improves the visibility of the high contrast details in bony areas and the brain soft-tissue. For example, the results show the ventricles and some brain folds become visible in SDIR reconstructed images and the contrast of the visible lesions is effectively improved. The line-pair resolution was improved from 12 line-pair/cm in FBP to 14 line-pair/cm in SDIR. Adjusting the parameters of the ASD-POCS to achieve 14 line-pair/cm caused the noise variance to be higher than the SDIR. Using these parameters for ASD-POCS, the MTF of FBP and ASD-POCS were very close and equal to 0.7 mm-1 which was increased to 1.2 mm-1 by SDIR, at half maximum.

Prime time sexual harassment.

PubMed

Grauerholz, E; King, A

1997-04-01

This study explores the explicit and implicit messages of sexual harassment that viewers receive when viewing prime-time television in the US. A content analysis of 48 hours of prime-time television reveals that sexual harassment on television is both highly visible and invisible. Sexual harassment is rendered visible simply by its prominence in these programs. Incidents involving quid-pro-quo harassment and environmental harassment occur with regularity on television. Furthermore, about 84% of the shows studied contained at least one incident of sexual harassment; yet these acts of sexual harassment remained largely invisible because none of the behaviors were labeled as sexual harassment. These incidents are presented in humorous ways, and victims are generally unharmed and very effective at ending the harassment. Although such programs may actually reflect the reality of many women's lives in terms of prevalence of sexual harassment, they perpetuate several myths about sexual harassment, such as that sexual harassment is not serious and that victims should be able to handle the situations themselves.

Television Viewing by Young Secondary Students: A Study of the Television Viewing Behavior of Children at Form Two Level.

ERIC Educational Resources Information Center

Powell, R. J.

Television viewing habits of 12 to 14 year olds in Australia were studied, and an attempt was made to correlate amount of viewing time and choice of programs with these children's intelligence and personality. Average viewing time per night was three hours and 40 minutes. A large variation was found in the time at which children ceased viewing.…

Total variation optimization for imaging through turbid media with transmission matrix

NASA Astrophysics Data System (ADS)

Gong, Changmei; Shao, Xiaopeng; Wu, Tengfei; Liu, Jietao; Zhang, Jianqi

2016-12-01

With the transmission matrix (TM) of the whole optical system measured, the image of the object behind a turbid medium can be recovered from its speckle field by means of an image reconstruction algorithm. Instead of Tikhonov regularization algorithm (TRA), the total variation minimization by augmented Lagrangian and alternating direction algorithms (TVAL3) is introduced to recover object images. As a total variation (TV)-based approach, TVAL3 allows to effectively damp more noise and preserve more edges compared with TRA, thus providing more outstanding image quality. Different levels of detector noise and TM-measurement noise are successively added to analyze the antinoise performance of these two algorithms. Simulation results show that TVAL3 is able to recover more details and suppress more noise than TRA under different noise levels, thus providing much more excellent image quality. Furthermore, whether it be detector noise or TM-measurement noise, the reconstruction images obtained by TVAL3 at SNR=15 dB are far superior to those by TRA at SNR=50 dB.

Symbolic Capital in a Virtual Heterosexual Market: Abbreviation and Insertion in Italian iTV SMS

ERIC Educational Resources Information Center

Herring, Susan C.; Zelenkauskaite, Asta

2009-01-01

This study analyzes gender variation in nonstandard typography--specifically, abbreviations and insertions--in mobile phone text messages (SMS) posted to a public Italian interactive television (iTV) program. All broadcast SMS were collected for a period of 2 days from the Web archive for the iTV program, and the frequency and distribution of…

Moving People from Science Adjacent to Science Doers with Twitch.tv

NASA Astrophysics Data System (ADS)

Gay, Pamela L.; CosmoQuest

2017-10-01

The CosmoQuest community is testing the ability to attract people from playing online videogames to doing fully online citizen science by engaging people through the Twitch.tv streaming platform. Twitch.tv launched in 2011 as an online platform for video gamers to stream their gameplay while providing narrative. In its six years of regular growth, the platform has added support for people playing non-video games, and for those participating in non-game activities. As part of their expansion, in April 2017, Twitch.tv hosted a science week during which they streamed the Cosmos series and allowed different feeds provide real-time commentary. They also hosted panel discussions on a variety of science topics. CosmoQuest participated in this event and used it as a jumping off point for beginning to interact with Twitch.tv community members online. With CosmoQuest’s beta launch of Image Detectives, they expanded their use of this streaming platform to include regular “office hours”, during which team members did science with CosmoQuest’s online projects, took questions from community members, and otherwise promoted the CosmoQuest community. This presentation examines this case study, and looks at how well different kinds of Twitter engagements attracted audiences, the conversion rate from viewer to subscriber, and at how effectively CosmoQuest was able to migrate users from viewing citizen science on Twitch.tv to participating in citizen science on CosmoQuest.org.This project was supported through NASA cooperative agreement NNX17AD20A.

Sharing the Good News: A Rural Approach to Publicizing Community College Library Services.

ERIC Educational Resources Information Center

Rothlisberg, Allen P.

The Northland Pioneer College (NPC) Library staff has developed a media blitz strategy to publicize its services in rural Arizona. This strategy regularly draws upon a database of newspapers, radio stations, and cable television outlets in the area. Each week a different public service announcement is developed and sent out to agencies on the…

How To Be Stupid: The Teachings of Channel One.

ERIC Educational Resources Information Center

Miller, Mark Crispin

The news on Channel One, with its impression of vague anxiety, looks and sounds like regular television news, only more so. In either case, the news is just "filler"--its real function is not journalistic but commercial, meant to lead into advertisements (ads). Mass advertising tends to assume that its audience will not be studying it…

Students Enrolled in the TV College, General Extension Division Fall 1965.

ERIC Educational Resources Information Center

Stecklein, John E.; And Others

In 1964 the University of Minnesota initiated a three-year TV College as an experiment in offering courses to more freshmen and sophomores without compromising quality. The four courses offered in 1964 and the nine in 1965 were taught by regular University faculty and carried full resident credit. They were supplemented by weekly discussion…

The Gratifications of Grazing: Why Flippers Flip.

ERIC Educational Resources Information Center

Walker, James R.; Bellamy, Robert V., Jr.

An exploratory study focused on usage patterns of television remote control devices (RCDs), examining how and why individuals use television RCDs to "graze." The study identified the gratifications obtained from RCD use and evaluated their relative importance in accounting for variations in RCD use. Subjects were 455 undergraduates in…

Structured Sparse Principal Components Analysis With the TV-Elastic Net Penalty.

PubMed

de Pierrefeu, Amicie; Lofstedt, Tommy; Hadj-Selem, Fouad; Dubois, Mathieu; Jardri, Renaud; Fovet, Thomas; Ciuciu, Philippe; Frouin, Vincent; Duchesnay, Edouard

2018-02-01

Principal component analysis (PCA) is an exploratory tool widely used in data analysis to uncover the dominant patterns of variability within a population. Despite its ability to represent a data set in a low-dimensional space, PCA's interpretability remains limited. Indeed, the components produced by PCA are often noisy or exhibit no visually meaningful patterns. Furthermore, the fact that the components are usually non-sparse may also impede interpretation, unless arbitrary thresholding is applied. However, in neuroimaging, it is essential to uncover clinically interpretable phenotypic markers that would account for the main variability in the brain images of a population. Recently, some alternatives to the standard PCA approach, such as sparse PCA (SPCA), have been proposed, their aim being to limit the density of the components. Nonetheless, sparsity alone does not entirely solve the interpretability problem in neuroimaging, since it may yield scattered and unstable components. We hypothesized that the incorporation of prior information regarding the structure of the data may lead to improved relevance and interpretability of brain patterns. We therefore present a simple extension of the popular PCA framework that adds structured sparsity penalties on the loading vectors in order to identify the few stable regions in the brain images that capture most of the variability. Such structured sparsity can be obtained by combining, e.g., and total variation (TV) penalties, where the TV regularization encodes information on the underlying structure of the data. This paper presents the structured SPCA (denoted SPCA-TV) optimization framework and its resolution. We demonstrate SPCA-TV's effectiveness and versatility on three different data sets. It can be applied to any kind of structured data, such as, e.g., -dimensional array images or meshes of cortical surfaces. The gains of SPCA-TV over unstructured approaches (such as SPCA and ElasticNet PCA) or structured approach (such as GraphNet PCA) are significant, since SPCA-TV reveals the variability within a data set in the form of intelligible brain patterns that are easier to interpret and more stable across different samples.

Statistical Interior Tomography

PubMed Central

Xu, Qiong; Wang, Ge; Sieren, Jered; Hoffman, Eric A.

2011-01-01

This paper presents a statistical interior tomography (SIT) approach making use of compressed sensing (CS) theory. With the projection data modeled by the Poisson distribution, an objective function with a total variation (TV) regularization term is formulated in the maximization of a posteriori (MAP) framework to solve the interior problem. An alternating minimization method is used to optimize the objective function with an initial image from the direct inversion of the truncated Hilbert transform. The proposed SIT approach is extensively evaluated with both numerical and real datasets. The results demonstrate that SIT is robust with respect to data noise and down-sampling, and has better resolution and less bias than its deterministic counterpart in the case of low count data. PMID:21233044

A Fourier-based compressed sensing technique for accelerated CT image reconstruction using first-order methods.

PubMed

Choi, Kihwan; Li, Ruijiang; Nam, Haewon; Xing, Lei

2014-06-21

As a solution to iterative CT image reconstruction, first-order methods are prominent for the large-scale capability and the fast convergence rate [Formula: see text]. In practice, the CT system matrix with a large condition number may lead to slow convergence speed despite the theoretically promising upper bound. The aim of this study is to develop a Fourier-based scaling technique to enhance the convergence speed of first-order methods applied to CT image reconstruction. Instead of working in the projection domain, we transform the projection data and construct a data fidelity model in Fourier space. Inspired by the filtered backprojection formalism, the data are appropriately weighted in Fourier space. We formulate an optimization problem based on weighted least-squares in the Fourier space and total-variation (TV) regularization in image space for parallel-beam, fan-beam and cone-beam CT geometry. To achieve the maximum computational speed, the optimization problem is solved using a fast iterative shrinkage-thresholding algorithm with backtracking line search and GPU implementation of projection/backprojection. The performance of the proposed algorithm is demonstrated through a series of digital simulation and experimental phantom studies. The results are compared with the existing TV regularized techniques based on statistics-based weighted least-squares as well as basic algebraic reconstruction technique. The proposed Fourier-based compressed sensing (CS) method significantly improves both the image quality and the convergence rate compared to the existing CS techniques.

Blind source deconvolution for deep Earth seismology

NASA Astrophysics Data System (ADS)

Stefan, W.; Renaut, R.; Garnero, E. J.; Lay, T.

2007-12-01

We present an approach to automatically estimate an empirical source characterization of deep earthquakes recorded teleseismically and subsequently remove the source from the recordings by applying regularized deconvolution. A principle goal in this work is to effectively deblur the seismograms, resulting in more impulsive and narrower pulses, permitting better constraints in high resolution waveform analyses. Our method consists of two stages: (1) we first estimate the empirical source by automatically registering traces to their 1st principal component with a weighting scheme based on their deviation from this shape, we then use this shape as an estimation of the earthquake source. (2) We compare different deconvolution techniques to remove the source characteristic from the trace. In particular Total Variation (TV) regularized deconvolution is used which utilizes the fact that most natural signals have an underlying spareness in an appropriate basis, in this case, impulsive onsets of seismic arrivals. We show several examples of deep focus Fiji-Tonga region earthquakes for the phases S and ScS, comparing source responses for the separate phases. TV deconvolution is compared to the water level deconvolution, Tikenov deconvolution, and L1 norm deconvolution, for both data and synthetics. This approach significantly improves our ability to study subtle waveform features that are commonly masked by either noise or the earthquake source. Eliminating source complexities improves our ability to resolve deep mantle triplications, waveform complexities associated with possible double crossings of the post-perovskite phase transition, as well as increasing stability in waveform analyses used for deep mantle anisotropy measurements.

Image Reconstruction from Under sampled Fourier Data Using the Polynomial Annihilation Transform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Archibald, Richard K.; Gelb, Anne; Platte, Rodrigo

Fourier samples are collected in a variety of applications including magnetic resonance imaging and synthetic aperture radar. The data are typically under-sampled and noisy. In recent years, l 1 regularization has received considerable attention in designing image reconstruction algorithms from under-sampled and noisy Fourier data. The underlying image is assumed to have some sparsity features, that is, some measurable features of the image have sparse representation. The reconstruction algorithm is typically designed to solve a convex optimization problem, which consists of a fidelity term penalized by one or more l 1 regularization terms. The Split Bregman Algorithm provides a fastmore » explicit solution for the case when TV is used for the l1l1 regularization terms. Due to its numerical efficiency, it has been widely adopted for a variety of applications. A well known drawback in using TV as an l 1 regularization term is that the reconstructed image will tend to default to a piecewise constant image. This issue has been addressed in several ways. Recently, the polynomial annihilation edge detection method was used to generate a higher order sparsifying transform, and was coined the “polynomial annihilation (PA) transform.” This paper adapts the Split Bregman Algorithm for the case when the PA transform is used as the l 1 regularization term. In so doing, we achieve a more accurate image reconstruction method from under-sampled and noisy Fourier data. Our new method compares favorably to the TV Split Bregman Algorithm, as well as to the popular TGV combined with shearlet approach.« less

Evaluation of social marketing of oral rehydration therapy.

PubMed

Koul, P B; Murali, M V; Gupta, P; Sharma, P P

1991-09-01

Attempts, at social marketing of oral rehydration therapy (ORT) through television, in changing the knowledge and practice of mothers with regard to its use was assessed. One hundred and eighty seven consecutive mothers (38 excluded due to non use of ORT) were administered a preplanned questionnaire to assess their socio-economic profile, educational status, concept of diarrhea and correct use of ORT. Fifty nine mothers who watched these programmes on TV regularly formed the study group. These were compared with 90 mothers who had gained such knowledge from non-television sources. The correct application of knowledge of ORT was significantly better in study group compared with control group. The educational status of mothers had a positive impact on motivation to use ORT at home in the study group. Mass media campaigns through "TV spots" is an effective way of improving knowledge of mothers on ORT in a developing country.

Confessions of an Accidental E/POnomer, from in Front of the Camera and Behind the Pixels

NASA Astrophysics Data System (ADS)

Durda, Daniel D.

2015-11-01

The various techniques, styles, and venues for popularizing the research outputs from our planetary science community reflect the diversity of the community itself. While some are eloquent public speakers or gifted writers, other colleagues are regularly sought for television appearances or for artwork to illustrate press releases. Whatever the method or medium, the collection of experiences we have had in ‘getting the word out’ represents a valuable resource pool of ideas and lessons learned from which we can all learn and improve. I will share some of my experiences from working with a number of television productions and magazine editors, with some thoughts on contemporary television production styles. I will also discuss life as both a planetary scientist and digital artist and share some resources that are ready, willing, and quite able to help tell the visual story of your research.

Vehicle Detection of Aerial Image Using TV-L1 Texture Decomposition

NASA Astrophysics Data System (ADS)

Wang, Y.; Wang, G.; Li, Y.; Huang, Y.

2016-06-01

Vehicle detection from high-resolution aerial image facilitates the study of the public traveling behavior on a large scale. In the context of road, a simple and effective algorithm is proposed to extract the texture-salient vehicle among the pavement surface. Texturally speaking, the majority of pavement surface changes a little except for the neighborhood of vehicles and edges. Within a certain distance away from the given vector of the road network, the aerial image is decomposed into a smoothly-varying cartoon part and an oscillatory details of textural part. The variational model of Total Variation regularization term and L1 fidelity term (TV-L1) is adopted to obtain the salient texture of vehicles and the cartoon surface of pavement. To eliminate the noise of texture decomposition, regions of pavement surface are refined by seed growing and morphological operation. Based on the shape saliency analysis of the central objects in those regions, vehicles are detected as the objects of rectangular shape saliency. The proposed algorithm is tested with a diverse set of aerial images that are acquired at various resolution and scenarios around China. Experimental results demonstrate that the proposed algorithm can detect vehicles at the rate of 71.5% and the false alarm rate of 21.5%, and that the speed is 39.13 seconds for a 4656 x 3496 aerial image. It is promising for large-scale transportation management and planning.

The medical geochemistry of dusts, soils, and other Earth materials: Chapter 7

USGS Publications Warehouse

Plumlee, Geoffrey S.; Ziegler, Thomas L.

2003-01-01

A quick scan of newspapers, television, science magazines, or the internet on any given day has a fairly high likelihood of encountering stories (accompanied by headlines such as those above) regarding human health concerns linked to dusts, soils, or other Earth materials. Many such concerns have been recognized and studied for decades, but new concerns arise regularly.

Not Our Regularly Scheduled Programming: Integrating Feminist Theory, Popular Culture, and Writing Pedagogy

ERIC Educational Resources Information Center

Gold, Alexandra

2016-01-01

When Alexandra Gold described her composition course: one that situates feminist and queer theory as a lens through which to view, analyze, and discuss contemporary television, a male acquaintance responded by saying he would not pay for that class. Another female acquaintance assured Gold that although she had loved a similar class at her Ivy…

Use of consumer survey data to target cessation messages to smokers through mass media.

PubMed

Nelson, David E; Gallogly, Meg; Pederson, Linda L; Barry, Matthew; McGoldrick, Daniel; Maibach, Edward W

2008-03-01

We identified the mass media channels that reach the most cigarette smokers in an attempt to more effectively target smoking cessation messages. Reach estimates and index scores for smokers were taken from 2002-2003 ConsumerStyles and HealthStyles national surveys of adults (N=11660) to estimate overall and demographic-specific exposure measures for television, radio, newspapers, and magazines. Smokers viewed more television, listened to more radio, and read fewer magazines and newspapers than did nonsmokers. Nearly one third of smokers were regular daytime or late-night television viewers. Selected cable television networks (USA, Lifetime, and Discovery Channel) and selected radio genres, such as classic rock and country, had high reach and were cost-efficient channels for targeting smokers. Certain mass media channels offer efficient opportunities to target smoking cessation messages so they reach relatively large audiences of smokers at relatively low cost. The approach used in this study can be applied to other types of health risk factors to improve health communication planning and increase efficiency of program media expenditures.

[Potential effects of screen media on cognitive development among children under 3 years old: review of literature].

PubMed

Brzozowska, Inga; Sikorska, Iwona

2016-01-01

The literature review regarding potential effects of screen media on cognitive development among children under 3 years old, is presented. In this article, cognitive aspects of development include acquisition of language, attention, learning and later school performance. The constant increase of children's access to television is noted, indicating that 60% of infants and toddlers watch TV regularly for 1-2 hours per day. The review included 40 articles and book chapters of significant such as Anderson, Barr, Christakis, Zimmerman, Meltzoff, Courage, Setliff, Troseth. The data was selected from electronic databases of scientific publications: Psychology & Behavioral Sciences Collection, Social Sciences Full Text (H.W. Wilson) and Humanities Full Text (H.W. Wilson) available in Poland. Cited articles provide evidence of the negative impact of exposure to television, media and video on the cognitive functioning of children under 3 years old. The potential impact of watching TV for difficulties in ability to focus attention appears as a core danger. Furthermore, studies suggest a possible connection between early exposure to television and ADHD as well as difficulties with language acquisition, learning and poorer school results.

The effects of television advertisements for junk food versus nutritious food on children's food attitudes and preferences.

PubMed

Dixon, Helen G; Scully, Maree L; Wakefield, Melanie A; White, Victoria M; Crawford, David A

2007-10-01

Television (TV) food advertising has attracted criticism for its potential role in promoting unhealthy dietary practices among children. Content analyses indicate junk food advertising is prevalent on Australian children's TV; healthy eating is rarely promoted. This paper presents (a) a cross-sectional survey examining associations between children's regular TV viewing habits and their food-related attitudes and behaviour; and (b) an experiment assessing the impact of varying combinations of TV advertisements (ads) for unhealthy and healthy foods on children's dietary knowledge, attitudes and intentions. The experimental conditions simulated possible models for regulating food ads on children's TV. Participants were 919 grade five and six students from schools in Melbourne, Australia. The survey showed that heavier TV use and more frequent commercial TV viewing were independently associated with more positive attitudes toward junk food; heavier TV use was also independently associated with higher reported junk food consumption. The experiment found that ads for nutritious foods promote selected positive attitudes and beliefs concerning these foods. Findings are discussed in light of methodological issues in media effects research and their implications for policy and practice. It is concluded that changing the food advertising environment on children's TV to one where nutritious foods are promoted and junk foods are relatively unrepresented would help to normalize and reinforce healthy eating.

Regularization Parameter Selection for Nonlinear Iterative Image Restoration and MRI Reconstruction Using GCV and SURE-Based Methods

PubMed Central

Ramani, Sathish; Liu, Zhihao; Rosen, Jeffrey; Nielsen, Jon-Fredrik; Fessler, Jeffrey A.

2012-01-01

Regularized iterative reconstruction algorithms for imaging inverse problems require selection of appropriate regularization parameter values. We focus on the challenging problem of tuning regularization parameters for nonlinear algorithms for the case of additive (possibly complex) Gaussian noise. Generalized cross-validation (GCV) and (weighted) mean-squared error (MSE) approaches (based on Stein's Unbiased Risk Estimate— SURE) need the Jacobian matrix of the nonlinear reconstruction operator (representative of the iterative algorithm) with respect to the data. We derive the desired Jacobian matrix for two types of nonlinear iterative algorithms: a fast variant of the standard iterative reweighted least-squares method and the contemporary split-Bregman algorithm, both of which can accommodate a wide variety of analysis- and synthesis-type regularizers. The proposed approach iteratively computes two weighted SURE-type measures: Predicted-SURE and Projected-SURE (that require knowledge of noise variance σ2), and GCV (that does not need σ2) for these algorithms. We apply the methods to image restoration and to magnetic resonance image (MRI) reconstruction using total variation (TV) and an analysis-type ℓ1-regularization. We demonstrate through simulations and experiments with real data that minimizing Predicted-SURE and Projected-SURE consistently lead to near-MSE-optimal reconstructions. We also observed that minimizing GCV yields reconstruction results that are near-MSE-optimal for image restoration and slightly sub-optimal for MRI. Theoretical derivations in this work related to Jacobian matrix evaluations can be extended, in principle, to other types of regularizers and reconstruction algorithms. PMID:22531764

The Preparation for the Equivalence Examinations, First and Second Levels in the State of Sao Paulo, Brazil: Traditional Means and Educational Media.

ERIC Educational Resources Information Center

Gatti, Bernardete A.

1988-01-01

Yearly in Sao Paulo (Brazil), official external examinations allow students outside the regular school system to obtain a certificate of education equivalent to grade 8 or 11. A television program that prepares candidates for the examinations and other forms of preparation are compared, using data collected for three years. (TJH)

A New Pansharpening Method Based on Spatial and Spectral Sparsity Priors.

PubMed

He, Xiyan; Condat, Laurent; Bioucas-Diaz, Jose; Chanussot, Jocelyn; Xia, Junshi

2014-06-27

The development of multisensor systems in recent years has led to great increase in the amount of available remote sensing data. Image fusion techniques aim at inferring high quality images of a given area from degraded versions of the same area obtained by multiple sensors. This paper focuses on pansharpening, which is the inference of a high spatial resolution multispectral image from two degraded versions with complementary spectral and spatial resolution characteristics: a) a low spatial resolution multispectral image; and b) a high spatial resolution panchromatic image. We introduce a new variational model based on spatial and spectral sparsity priors for the fusion. In the spectral domain we encourage low-rank structure, whereas in the spatial domain we promote sparsity on the local differences. Given the fact that both panchromatic and multispectral images are integrations of the underlying continuous spectra using different channel responses, we propose to exploit appropriate regularizations based on both spatial and spectral links between panchromatic and the fused multispectral images. A weighted version of the vector Total Variation (TV) norm of the data matrix is employed to align the spatial information of the fused image with that of the panchromatic image. With regard to spectral information, two different types of regularization are proposed to promote a soft constraint on the linear dependence between the panchromatic and the fused multispectral images. The first one estimates directly the linear coefficients from the observed panchromatic and low resolution multispectral images by Linear Regression (LR) while the second one employs the Principal Component Pursuit (PCP) to obtain a robust recovery of the underlying low-rank structure. We also show that the two regularizers are strongly related. The basic idea of both regularizers is that the fused image should have low-rank and preserve edge locations. We use a variation of the recently proposed Split Augmented Lagrangian Shrinkage (SALSA) algorithm to effectively solve the proposed variational formulations. Experimental results on simulated and real remote sensing images show the effectiveness of the proposed pansharpening method compared to the state-of-the-art.

Trends in exposure to televised prescription drug advertising, 2003-2011.

PubMed

Kornfield, Rachel; Alexander, G Caleb; Qato, Dima M; Kim, Yoonsang; Hirsch, Jan D; Emery, Sherry L

2015-05-01

TV accounts for more than half of pharmaceutical direct-to-consumer advertising (DTCA) spending in the U.S. The purpose of this study is to quantify average household exposure to branded and non-branded (help-seeking) televised prescription drug advertisements and describe variation over time and according to medication indication and geography. In 2013, Nielsen TV ratings were compiled for prescription pharmaceutical advertising that aired between 2003 and 2011 for the top 75 U.S. media markets. All advertisements were coded as branded or help-seeking. Advertisements were further coded for one of eight prevalent indications (allergies, arthritis, asthma, erectile dysfunction, high cholesterol, smoking cessation, depression, and sleep disorder) or as "other." Televised DTCA exposure increased from 2003 to 2007 and then declined 43% by 2011, to 111 monthly prescription drug advertisements per household. The examined indications were associated with varying amounts and patterns of exposure, with greatest declines among medications for allergies and sleep disorders. Help-seeking advertisements comprised 10% of total exposure, with substantial variation by indication. Considerations of DTCA's effects on health care should take into account the shifting concentration of advertising across indications. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Trends in Exposure to Televised Prescription Drug Advertising, 2003–2011

PubMed Central

Kornfield, Rachel; Alexander, G. Caleb; Qato, Dima M.; Kim, Yoonsang; Hirsch, Jan D.; Emery, Sherry L.

2015-01-01

Introduction TV accounts for over half of pharmaceutical direct-to-consumer advertising (DTCA) spending in the U.S. The purpose of this study is to quantify average household exposure to branded and non-branded (help-seeking) televised prescription drug advertisements and describe variation over time and according to medication indication and geography. Methods In 2013, Nielsen TV ratings were compiled for prescription pharmaceutical advertising that aired between 2003 and 2011 for the top 75 U.S. media markets. All advertisements were coded as branded or help-seeking. Advertisements were further coded for one of eight prevalent indications (allergies, arthritis, asthma, erectile dysfunction, high cholesterol, smoking cessation, depression, and sleep disorder) or as “other.” Results Televised DTCA exposure increased from 2003 to 2007 and then declined 43% by 2011, to 111 monthly prescription drug advertisements per household. The examined indications were associated with varying amounts and patterns of exposure, with greatest declines among medications for allergies and sleep disorders. Help-seeking advertisements comprised 10% of total exposure, with substantial variation by indication. Conclusions Considerations of DTCA's effects on health care should take into account the shifting concentration of advertising across indications. PMID:25891057

Adaptive-weighted Total Variation Minimization for Sparse Data toward Low-dose X-ray Computed Tomography Image Reconstruction

PubMed Central

Liu, Yan; Ma, Jianhua; Fan, Yi; Liang, Zhengrong

2012-01-01

Previous studies have shown that by minimizing the total variation (TV) of the to-be-estimated image with some data and other constraints, a piecewise-smooth X-ray computed tomography (CT) can be reconstructed from sparse-view projection data without introducing noticeable artifacts. However, due to the piecewise constant assumption for the image, a conventional TV minimization algorithm often suffers from over-smoothness on the edges of the resulting image. To mitigate this drawback, we present an adaptive-weighted TV (AwTV) minimization algorithm in this paper. The presented AwTV model is derived by considering the anisotropic edge property among neighboring image voxels, where the associated weights are expressed as an exponential function and can be adaptively adjusted by the local image-intensity gradient for the purpose of preserving the edge details. Inspired by the previously-reported TV-POCS (projection onto convex sets) implementation, a similar AwTV-POCS implementation was developed to minimize the AwTV subject to data and other constraints for the purpose of sparse-view low-dose CT image reconstruction. To evaluate the presented AwTV-POCS algorithm, both qualitative and quantitative studies were performed by computer simulations and phantom experiments. The results show that the presented AwTV-POCS algorithm can yield images with several noticeable gains, in terms of noise-resolution tradeoff plots and full width at half maximum values, as compared to the corresponding conventional TV-POCS algorithm. PMID:23154621

Adaptive-weighted total variation minimization for sparse data toward low-dose x-ray computed tomography image reconstruction.

PubMed

Liu, Yan; Ma, Jianhua; Fan, Yi; Liang, Zhengrong

2012-12-07

Previous studies have shown that by minimizing the total variation (TV) of the to-be-estimated image with some data and other constraints, piecewise-smooth x-ray computed tomography (CT) can be reconstructed from sparse-view projection data without introducing notable artifacts. However, due to the piecewise constant assumption for the image, a conventional TV minimization algorithm often suffers from over-smoothness on the edges of the resulting image. To mitigate this drawback, we present an adaptive-weighted TV (AwTV) minimization algorithm in this paper. The presented AwTV model is derived by considering the anisotropic edge property among neighboring image voxels, where the associated weights are expressed as an exponential function and can be adaptively adjusted by the local image-intensity gradient for the purpose of preserving the edge details. Inspired by the previously reported TV-POCS (projection onto convex sets) implementation, a similar AwTV-POCS implementation was developed to minimize the AwTV subject to data and other constraints for the purpose of sparse-view low-dose CT image reconstruction. To evaluate the presented AwTV-POCS algorithm, both qualitative and quantitative studies were performed by computer simulations and phantom experiments. The results show that the presented AwTV-POCS algorithm can yield images with several notable gains, in terms of noise-resolution tradeoff plots and full-width at half-maximum values, as compared to the corresponding conventional TV-POCS algorithm.

FOREWORD: Tackling inverse problems in a Banach space environment: from theory to applications Tackling inverse problems in a Banach space environment: from theory to applications

NASA Astrophysics Data System (ADS)

Schuster, Thomas; Hofmann, Bernd; Kaltenbacher, Barbara

2012-10-01

Inverse problems can usually be modelled as operator equations in infinite-dimensional spaces with a forward operator acting between Hilbert or Banach spaces—a formulation which quite often also serves as the basis for defining and analyzing solution methods. The additional amount of structure and geometric interpretability provided by the concept of an inner product has rendered these methods amenable to a convergence analysis, a fact which has led to a rigorous and comprehensive study of regularization methods in Hilbert spaces over the last three decades. However, for numerous problems such as x-ray diffractometry, certain inverse scattering problems and a number of parameter identification problems in PDEs, the reasons for using a Hilbert space setting seem to be based on conventions rather than an appropriate and realistic model choice, so often a Banach space setting would be closer to reality. Furthermore, non-Hilbertian regularization and data fidelity terms incorporating a priori information on solution and noise, such as general Lp-norms, TV-type norms, or the Kullback-Leibler divergence, have recently become very popular. These facts have motivated intensive investigations on regularization methods in Banach spaces, a topic which has emerged as a highly active research field within the area of inverse problems. Meanwhile some of the most well-known regularization approaches, such as Tikhonov-type methods requiring the solution of extremal problems, and iterative ones like the Landweber method, the Gauss-Newton method, as well as the approximate inverse method, have been investigated for linear and nonlinear operator equations in Banach spaces. Convergence with rates has been proven and conditions on the solution smoothness and on the structure of nonlinearity have been formulated. Still, beyond the existing results a large number of challenging open questions have arisen, due to the more involved handling of general Banach spaces and the larger variety of concrete instances with special properties. The aim of this special section is to provide a forum for highly topical ongoing work in the area of regularization in Banach spaces, its numerics and its applications. Indeed, we have been lucky enough to obtain a number of excellent papers both from colleagues who have previously been contributing to this topic and from researchers entering the field due to its relevance in practical inverse problems. We would like to thank all contributers for enabling us to present a high quality collection of papers on topics ranging from various aspects of regularization via efficient numerical solution to applications in PDE models. We give a brief overview of the contributions included in this issue (here ordered alphabetically by first author). In their paper, Iterative regularization with general penalty term—theory and application to L1 and TV regularization, Radu Bot and Torsten Hein provide an extension of the Landweber iteration for linear operator equations in Banach space to general operators in place of the inverse duality mapping, which corresponds to the use of general regularization functionals in variational regularization. The L∞ topology in data space corresponds to the frequently occuring situation of uniformly distributed data noise. A numerically efficient solution of the resulting Tikhonov regularization problem via a Moreau-Yosida appriximation and a semismooth Newton method, along with a δ-free regularization parameter choice rule, is the topic of the paper L∞ fitting for inverse problems with uniform noise by Christian Clason. Extension of convergence rates results from classical source conditions to their generalization via variational inequalities with a priori and a posteriori stopping rules is the main contribution of the paper Regularization of linear ill-posed problems by the augmented Lagrangian method and variational inequalities by Klaus Frick and Markus Grasmair, again in the context of some iterative method. A powerful tool for proving convergence rates of Tikhonov type but also other regularization methods in Banach spaces are assumptions of the type of variational inequalities that combine conditions on solution smoothness (i.e., source conditions in the Hilbert space case) and nonlinearity of the forward operator. In Parameter choice in Banach space regularization under variational inequalities, Bernd Hofmann and Peter Mathé provide results with general error measures and especially study the question of regularization parameter choice. Daijun Jiang, Hui Feng, and Jun Zou consider an application of Banach space ideas in the context of an application problem in their paper Convergence rates of Tikhonov regularizations for parameter identifiation in a parabolic-elliptic system, namely the identification of a distributed diffusion coefficient in a coupled elliptic-parabolic system. In particular, they show convergence rates of Lp-H1 (variational) regularization for the application under consideration via the use and verification of certain source and nonlinearity conditions. In computational practice, the Lp norm with p close to one is often used as a substitute for the actually sparsity promoting L1 norm. In Norm sensitivity of sparsity regularization with respect to p, Kamil S Kazimierski, Peter Maass and Robin Strehlow consider the question of how sensitive the Tikhonov regularized solution is with respect to p. They do so by computing the derivative via the implicit function theorem, particularly at the crucial value, p=1. Another iterative regularization method in Banach space is considered by Qinian Jin and Linda Stals in Nonstationary iterated Tikhonov regularization for ill-posed problems in Banach spaces. Using a variational formulation and under some smoothness and convexity assumption on the preimage space, they extend the convergence analysis of the well-known iterative Tikhonov method for linear problems in Hilbert space to a more general Banach space framework. Systems of linear or nonlinear operators can be efficiently treated by cyclic iterations, thus several variants of gradient and Newton-type Kaczmarz methods have already been studied in the Hilbert space setting. Antonio Leitão and M Marques Alves in their paper On Landweber---Kaczmarz methods for regularizing systems of ill-posed equations in Banach spaces carry out an extension to Banach spaces for the fundamental Landweber version. The impact of perturbations in the evaluation of the forward operator and its derivative on the convergence behaviour of regularization methods is a practically and highly relevant issue. It is treated in the paper Convergence rates analysis of Tikhonov regularization for nonlinear ill-posed problems with noisy operators by Shuai Lu and Jens Flemming for variational regularization of nonlinear problems in Banach spaces. In The approximate inverse in action: IV. Semi-discrete equations in a Banach space setting, Thomas Schuster, Andreas Rieder and Frank Schöpfer extend the concept of approximate inverse to the practically and highly relevant situation of finitely many measurements and a general smooth and convex Banach space as preimage space. They devise two approaches for computing the reconstruction kernels required in the method and provide convergence and regularization results. Frank Werner and Thorsten Hohage in Convergence rates in expectation for Tikhonov-type regularization of inverse problems with Poisson data prove convergence rates results for variational regularization with general convex regularization term and the Kullback-Leibler distance as data fidelity term by combining a new result on Poisson distributed data with a deterministic rates analysis. Finally, we would like to thank the Inverse Problems team, especially Joanna Evangelides and Chris Wileman, for their extraordinary smooth and productive cooperation, as well as Alfred K Louis for his kind support of our initiative.

East Europe Report Economic and Industrial Affairs No. 2390

DTIC Science & Technology

1983-04-22

Discussed (B-. GIilan, et al .; BORBA , 7 Mar 83) ......................... 89 -b - ALBANIA DEVELOPMENTS IN COLOR TELEVISION BROADCASTING Tirana BASHKIMI...experiment- al work was carried on with limited and irregular schedules. The beginning of regular programming coincided with the 6th party congress in...upheav- als . But the practice of permanent revolution has set back for a long time even such a huge country, with a great cultural heritage, enormous

Scatter correction in cone-beam CT via a half beam blocker technique allowing simultaneous acquisition of scatter and image information

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Ho; Xing Lei; Lee, Rena

2012-05-15

Purpose: X-ray scatter incurred to detectors degrades the quality of cone-beam computed tomography (CBCT) and represents a problem in volumetric image guided and adaptive radiation therapy. Several methods using a beam blocker for the estimation and subtraction of scatter have been proposed. However, due to missing information resulting from the obstruction of the blocker, such methods require dual scanning or dynamically moving blocker to obtain a complete volumetric image. Here, we propose a half beam blocker-based approach, in conjunction with a total variation (TV) regularized Feldkamp-Davis-Kress (FDK) algorithm, to correct scatter-induced artifacts by simultaneously acquiring image and scatter information frommore » a single-rotation CBCT scan. Methods: A half beam blocker, comprising lead strips, is used to simultaneously acquire image data on one side of the projection data and scatter data on the other half side. One-dimensional cubic B-Spline interpolation/extrapolation is applied to derive patient specific scatter information by using the scatter distributions on strips. The estimated scatter is subtracted from the projection image acquired at the opposite view. With scatter-corrected projections where this subtraction is completed, the FDK algorithm based on a cosine weighting function is performed to reconstruct CBCT volume. To suppress the noise in the reconstructed CBCT images produced by geometric errors between two opposed projections and interpolated scatter information, total variation regularization is applied by a minimization using a steepest gradient descent optimization method. The experimental studies using Catphan504 and anthropomorphic phantoms were carried out to evaluate the performance of the proposed scheme. Results: The scatter-induced shading artifacts were markedly suppressed in CBCT using the proposed scheme. Compared with CBCT without a blocker, the nonuniformity value was reduced from 39.3% to 3.1%. The root mean square error relative to values inside the regions of interest selected from a benchmark scatter free image was reduced from 50 to 11.3. The TV regularization also led to a better contrast-to-noise ratio. Conclusions: An asymmetric half beam blocker-based FDK acquisition and reconstruction technique has been established. The proposed scheme enables simultaneous detection of patient specific scatter and complete volumetric CBCT reconstruction without additional requirements such as prior images, dual scans, or moving strips.« less

A content analysis of food references in television programming specifically targeting viewing audiences aged 11 to 14 years.

PubMed

Roseman, Mary G; Poor, Morgan; Stephenson, Tammy J

2014-01-01

Examine food in cable television programming specifically targeting 11- to 14-year-olds ("tweens"). Content analysis of food-related scenes (FRS)-in which food was shown, mentioned, and/or consumed-in 880 minutes of programming was conducted. Five days of afternoon/early evening television programs on the Disney Channel. Food references were compared with USDA MyPlate and classified according to modified Ratio of Recommended to Restricted Food Components. The authors found 331 FRS, averaging 16.6 scenes/h. Preponderance of FRS was physiological needs (40.7%), followed by display (10%), party (8.5%), social event (8%), and retail store (6.6%). Snacks dominated 41% of FRS, and breakfast, lunch, and dinner were much lower in frequency. Half of FRS was visual only, followed by verbal only. Food references were not congruent with MyPlate recommendations; 42% of food items did not fit into MyPlate food groups. Only 24% of food items were fruit or vegetables, which is considerably less than recommended by MyPlate guidelines. Using modified Ratio of Recommended to Restricted Food Components, 66% of food items scored < 1.0, signifying less nutritious. Tween television programming regularly includes non-nutritious food, which likely influences tweens' attitudes and behaviors. Television programming may consider past approaches to tobacco smoking and health messages on television. More attention is warranted regarding television programming by nutrition educators, researchers, health professionals, and industry specialists. Copyright © 2014 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

The role of television viewing and direct experience in predicting adolescents’ beliefs about the health risks of fast-food consumption

PubMed Central

Russell, Cristel Antonia; Buhrau, Denise

2015-01-01

Background Fast-food advertising abounds on television (TV), and programs targeting youth often display fast-food consumption but rarely with any negative consequences. Cultivation research maintains that cumulative exposure to TV influences audiences’ views of and beliefs about the real world. Thus, the amount of TV adolescents watch is likely to bias their views of the consequences of eating fast food. This research posits that this relationship varies as a function of adolescents’ actual experience with fast food. Method Two cross-sectional surveys conducted in the cultivation research tradition assess the relationship between the amount of adolescents’ regular exposure to TV and their beliefs about the risks and benefits of eating fast food. Teenage children of members of online panels reported hours of TV viewing, beliefs about the consequences of eating fast food, and their frequency of fast-food consumption. Results In both studies, beliefs about health risks of fast-food consumption vary as a function of the amount of TV watched. Heavy TV viewers have less negative and more positive beliefs about the consequences of fast-food consumption than light viewers. As direct experience with fast food increases, the relationship between TV viewing and risk perceptions weakens, but the relationship between TV viewing and positive perceptions strengthens. These moderated relationships remain when we control for physical activity (Study 1) and the density of fast-food restaurants in respondents’ geographical area (Study 2). Conclusion Given the role of TV viewing in biasing perceptions of the consequences of eating fast food, public health researchers and practitioners should carefully monitor and perhaps regulate the amount of fast-food advertising on TV and the content of TV programs. PMID:26009205

The role of television viewing and direct experience in predicting adolescents' beliefs about the health risks of fast-food consumption.

PubMed

Russell, Cristel Antonia; Buhrau, Denise

2015-09-01

Fast-food advertising abounds on television (TV), and programs targeting youth often display fast-food consumption but rarely with any negative consequences. Cultivation research maintains that cumulative exposure to TV influences audiences' views of and beliefs about the real world. Thus, the amount of TV adolescents watch is likely to bias their views of the consequences of eating fast food. This research posits that this relationship varies as a function of adolescents' actual experience with fast food. Two cross-sectional surveys conducted in the cultivation research tradition assess the relationship between the amount of adolescents' regular exposure to TV and their beliefs about the risks and benefits of eating fast food. Teenage children of members of online panels reported hours of TV viewing, beliefs about the consequences of eating fast food, and their frequency of fast-food consumption. In both studies, beliefs about health risks of fast-food consumption vary as a function of the amount of TV watched. Heavy TV viewers have less negative and more positive beliefs about the consequences of fast-food consumption than light viewers. As direct experience with fast food increases, the relationship between TV viewing and risk perceptions weakens, but the relationship between TV viewing and positive perceptions strengthens. These moderated relationships remain when we control for physical activity (Study 1) and the density of fast-food restaurants in respondents' geographical area (Study 2). Given the role of TV viewing in biasing perceptions of the consequences of eating fast food, public health researchers and practitioners should carefully monitor and perhaps regulate the amount of fast-food advertising on TV and the content of TV programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Use of fictional medical television in health sciences education: a systematic review.

PubMed

Hoffman, Beth L; Hoffman, Robert; Wessel, Charles B; Shensa, Ariel; Woods, Michelle S; Primack, Brian A

2018-03-01

While medical television programs are popular among health profession trainees, it is not clear to what extent these programs affect their knowledge, perceptions, and/or behaviors. Therefore, we conducted a systematic review of research evaluating associations between program exposure and outcomes. We conducted systematic literature searches in Pubmed, CINAHL, and PsycINFO. Selected studies were required to be scholarly research, involve exposure to fictionalized medical television programming by health professional students, and assess associations between exposure and outcomes. Studies were classified according to quality and factors related to population, exposure, and outcomes. Of 3541 studies identified, 13 met selection criteria. Six studies involved undergraduate medical students, one involved nursing students, two involved both medical and nursing students, two involved medical residents, one involved medical students, residents and attending physicians, and one involved graduate epidemiology students. Mean study quality according to the MERSQI was 8.27. The most commonly assessed television programs were ER and Grey's Anatomy (six each). Five studies assessed regular viewing habits, and found that fictional medical programs are popular among students and that students recall health topics from episodes. The eight studies that assessed the association with outcomes when using clips as educational tools reported high satisfaction and increased knowledge of the presented health topics. While relatively few published studies have explored influences of fictional medical television on health professional students, those conducted suggest that students often view these television programs independently and that integration of this programming into medical education is feasible and acceptable.

Engaging All Americans: Innovative Strategies for Reaching the Public with Climate and Environmental Information

NASA Astrophysics Data System (ADS)

Espinoza, S.

2014-12-01

From extensive drought and heat waves to floods, tornadoes and Superstorm Sandy, extreme weather and climate events provide teachable moments to help communities prepare for and respond to related environmental, economic and health impacts. The National Environmental Education Foundation (www.neefusa.org) works with the American Meteorological Society, the media and other trusted messengers to provide weather, climate and environmental information to the public in accessible and widely used formats, whether via TV, radio or social media. NEEF will provide an overview of innovative partnerships and projects that are engaging Americans in understanding and using climate and environmental information to make the best choices in their daily lives and improve the health of their communities, including: Assessing knowledge, attitudes and behaviors: NEEF will share results from its national survey research and targeted focus groups on current attitudes and practices relating to our nation's environment. Simplifying and amplifying key messages: NEEF provides a national network of more than 350 meteorologists, radio broadcasters and journalists with the science-based information and resources they need to present climate and environmental topics to their viewers on-air, online and in community outreach. Engaging television viewers in citizen science: Eyes on Central PA, a pilot project of NEEF, Project Noah and WTAJ-TV, harnesses Project Noah's citizen science platform to collect and display photos of wildlife from WTAJ-TV viewers. NEEF and WTAJ provide regular blogs and on-air stories that highlight viewers' photos and link them to local weather conditions and climate trends. Expanding the conversation: NEEF's multimedia strategy in the Mid-Atlantic U.S. is reaching Spanish-speaking audiences with climate and environmental information through regular radio and television broadcasts. We are also exploring ways to reach other non-traditional audiences, including faith communities and sports fans, with weather, climate and preparedness information.

A new Mumford-Shah total variation minimization based model for sparse-view x-ray computed tomography image reconstruction.

PubMed

Chen, Bo; Bian, Zhaoying; Zhou, Xiaohui; Chen, Wensheng; Ma, Jianhua; Liang, Zhengrong

2018-04-12

Total variation (TV) minimization for the sparse-view x-ray computer tomography (CT) reconstruction has been widely explored to reduce radiation dose. However, due to the piecewise constant assumption for the TV model, the reconstructed images often suffer from over-smoothness on the image edges. To mitigate this drawback of TV minimization, we present a Mumford-Shah total variation (MSTV) minimization algorithm in this paper. The presented MSTV model is derived by integrating TV minimization and Mumford-Shah segmentation. Subsequently, a penalized weighted least-squares (PWLS) scheme with MSTV is developed for the sparse-view CT reconstruction. For simplicity, the proposed algorithm is named as 'PWLS-MSTV.' To evaluate the performance of the present PWLS-MSTV algorithm, both qualitative and quantitative studies were conducted by using a digital XCAT phantom and a physical phantom. Experimental results show that the present PWLS-MSTV algorithm has noticeable gains over the existing algorithms in terms of noise reduction, contrast-to-ratio measure and edge-preservation.

The Evaluations of Swine Flu Magnitudes in TV News: A Comparative Analysis of Paired Influenza Pandemics.

PubMed

Pan, Po-Lin; Meng, Juan

2015-01-01

This study examined how major TV news networks covered two flu pandemics in 1976 and 2009 in terms of news frames, mortality exemplars, mortality subject attributes, vaccination, evaluation approaches, and news sources. Results showed that the first pandemic was frequently framed with the medical/scientific and political/legal issues, while the second pandemic was emphasized with the health risk issue in TV news. Both flu pandemics were regularly reported with mortality exemplars, but the focus in the first pandemic was on the flu virus threat and vaccination side effects, while the vaccination shortage was frequently revealed in the second outbreak.

Violence on Canadian Television Networks

PubMed Central

Paquette, Guy

2004-01-01

Introduction Over the past twenty years, the question of the effects of violence on television has figured prominently in public opinion and hundreds of studies have been devoted to this subject. Many researchers have determined that violence has a negative impact on behavior. The public, broadcasters and political figures all support the idea of reducing the total amount of violence on television - in particular in shows for children. A thousand programs aired between 1993 and 2001 on major non-specialty television networks in Canada were analyzed: TVA, TQS, as well as CTV and Global, private French and English networks, as well as the English CBC Radio and French Radio-Canada for the public networks. Method The methodology consists of a classic analysis of content where an act of violence constitutes a unit of analysis. Results The data collected revealed that the amount of violence has increased regularly since 1993 despite the stated willingness on the part of broadcasters to produce programs with less violence. The total number of violent acts, as well as the number of violent acts per hour, is increasing. Private networks deliver three times more violence than public networks. Researchers have also noted that a high proportion of violence occurs in programs airing before 21:00 hours, thereby exposing a large number of children to this violence. Conclusion Psychological violence is taking on a more significant role in Canadian Television. PMID:19030148

Violence on canadian television networks.

PubMed

Paquette, Guy

2004-02-01

Over the past twenty years, the question of the effects of violence on television has figured prominently in public opinion and hundreds of studies have been devoted to this subject. Many researchers have determined that violence has a negative impact on behavior. The public, broadcasters and political figures all support the idea of reducing the total amount of violence on television - in particular in shows for children. A thousand programs aired between 1993 and 2001 on major non-specialty television networks in Canada were analyzed: TVA, TQS, as well as CTV and Global, private French and English networks, as well as the English CBC Radio and French Radio-Canada for the public networks. The methodology consists of a classic analysis of content where an act of violence constitutes a unit of analysis. The data collected revealed that the amount of violence has increased regularly since 1993 despite the stated willingness on the part of broadcasters to produce programs with less violence. The total number of violent acts, as well as the number of violent acts per hour, is increasing. Private networks deliver three times more violence than public networks. Researchers have also noted that a high proportion of violence occurs in programs airing before 21:00 hours, thereby exposing a large number of children to this violence. Psychological violence is taking on a more significant role in Canadian Television.

Low-altitude acceleration of auroral electrons during breakup observed by a mother-daughter rocket

NASA Technical Reports Server (NTRS)

Johnstone, A. D.; Davis, T. N.

1974-01-01

By the use of a mother-daughter rocket combination and ground-based observations with television, time and space variations are resolved in particle measurements in breakup aurora. The spectral variations measured during a temporal variation in the aurora can be explained by a nearly uniform acceleration of all the electrons such as would be caused by an electric potential drop along the magnetic field lines. Many other explanations can be eliminated.

Low Dose PET Image Reconstruction with Total Variation Using Alternating Direction Method.

PubMed

Yu, Xingjian; Wang, Chenye; Hu, Hongjie; Liu, Huafeng

2016-01-01

In this paper, a total variation (TV) minimization strategy is proposed to overcome the problem of sparse spatial resolution and large amounts of noise in low dose positron emission tomography (PET) imaging reconstruction. Two types of objective function were established based on two statistical models of measured PET data, least-square (LS) TV for the Gaussian distribution and Poisson-TV for the Poisson distribution. To efficiently obtain high quality reconstructed images, the alternating direction method (ADM) is used to solve these objective functions. As compared with the iterative shrinkage/thresholding (IST) based algorithms, the proposed ADM can make full use of the TV constraint and its convergence rate is faster. The performance of the proposed approach is validated through comparisons with the expectation-maximization (EM) method using synthetic and experimental biological data. In the comparisons, the results of both LS-TV and Poisson-TV are taken into consideration to find which models are more suitable for PET imaging, in particular low-dose PET. To evaluate the results quantitatively, we computed bias, variance, and the contrast recovery coefficient (CRC) and drew profiles of the reconstructed images produced by the different methods. The results show that both Poisson-TV and LS-TV can provide a high visual quality at a low dose level. The bias and variance of the proposed LS-TV and Poisson-TV methods are 20% to 74% less at all counting levels than those of the EM method. Poisson-TV gives the best performance in terms of high-accuracy reconstruction with the lowest bias and variance as compared to the ground truth (14.3% less bias and 21.9% less variance). In contrast, LS-TV gives the best performance in terms of the high contrast of the reconstruction with the highest CRC.

Low Dose PET Image Reconstruction with Total Variation Using Alternating Direction Method

PubMed Central

Yu, Xingjian; Wang, Chenye; Hu, Hongjie; Liu, Huafeng

2016-01-01

In this paper, a total variation (TV) minimization strategy is proposed to overcome the problem of sparse spatial resolution and large amounts of noise in low dose positron emission tomography (PET) imaging reconstruction. Two types of objective function were established based on two statistical models of measured PET data, least-square (LS) TV for the Gaussian distribution and Poisson-TV for the Poisson distribution. To efficiently obtain high quality reconstructed images, the alternating direction method (ADM) is used to solve these objective functions. As compared with the iterative shrinkage/thresholding (IST) based algorithms, the proposed ADM can make full use of the TV constraint and its convergence rate is faster. The performance of the proposed approach is validated through comparisons with the expectation-maximization (EM) method using synthetic and experimental biological data. In the comparisons, the results of both LS-TV and Poisson-TV are taken into consideration to find which models are more suitable for PET imaging, in particular low-dose PET. To evaluate the results quantitatively, we computed bias, variance, and the contrast recovery coefficient (CRC) and drew profiles of the reconstructed images produced by the different methods. The results show that both Poisson-TV and LS-TV can provide a high visual quality at a low dose level. The bias and variance of the proposed LS-TV and Poisson-TV methods are 20% to 74% less at all counting levels than those of the EM method. Poisson-TV gives the best performance in terms of high-accuracy reconstruction with the lowest bias and variance as compared to the ground truth (14.3% less bias and 21.9% less variance). In contrast, LS-TV gives the best performance in terms of the high contrast of the reconstruction with the highest CRC. PMID:28005929

47 CFR 73.621 - Noncommercial educational TV stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... interrupt regular programming. Note: Commission interpretation of this rule, including the acceptable form... Blanking Interval and in the Visual Signal. The provisions governing VBI and visual signal...

47 CFR 73.621 - Noncommercial educational TV stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... interrupt regular programming. Note: Commission interpretation of this rule, including the acceptable form... Blanking Interval and in the Visual Signal. The provisions governing VBI and visual signal...

An integrated process and management tools for ranking multiple emerging threats to animal health.

PubMed

Del Rio Vilas, Victor J; Voller, Fay; Montibeller, Gilberto; Franco, L Alberto; Sribhashyam, Sumitra; Watson, Eamon; Hartley, Matt; Gibbens, Jane C

2013-02-01

The UK's Department for Environment, Food and Rural Affairs supports the use of systematic tools for the prioritisation of known and well defined animal diseases to facilitate long and medium term planning of surveillance and disease control activities. The recognition that emerging events were not covered by the existing disease-specific approaches led to the establishment of the Veterinary Risk Group (VRG), constituted of government officials, and supporting structures such as the Risk Management Cycle and the Emerging Threat Highlight Report (ETHiR), to facilitate the identification, reporting and assessment of emerging threats to UK's animal health. Since its inception in November 2009 to the end of February 2011, the VRG reviewed 111 threats and vulnerabilities (T&V) reported through ETHiR. In July 2010 a decision support system (DSS) based on multi-criteria-decision-analysis (MCDA) improved ETHiR to allow the systematic prioritisation of emerging T&V. The DSS allows the regular ranking of emerging T&V by calculating a set of measurement indices related to the actual impact, possible impact on public perception and level of available capabilities associated with every T&V. The systematic characterisation of the processes leading to the assessment of T&V by the VRG has led to a consistent, auditable and transparent approach to the identification and assessment of emerging risks. The regular use of MCDA to manage a portfolio of emerging risks represents a different and novel application of MCDA in a health related context. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

Color Image Restoration Using Nonlocal Mumford-Shah Regularizers

NASA Astrophysics Data System (ADS)

Jung, Miyoun; Bresson, Xavier; Chan, Tony F.; Vese, Luminita A.

We introduce several color image restoration algorithms based on the Mumford-Shah model and nonlocal image information. The standard Ambrosio-Tortorelli and Shah models are defined to work in a small local neighborhood, which are sufficient to denoise smooth regions with sharp boundaries. However, textures are not local in nature and require semi-local/non-local information to be denoised efficiently. Inspired from recent work (NL-means of Buades, Coll, Morel and NL-TV of Gilboa, Osher), we extend the standard models of Ambrosio-Tortorelli and Shah approximations to Mumford-Shah functionals to work with nonlocal information, for better restoration of fine structures and textures. We present several applications of the proposed nonlocal MS regularizers in image processing such as color image denoising, color image deblurring in the presence of Gaussian or impulse noise, color image inpainting, and color image super-resolution. In the formulation of nonlocal variational models for the image deblurring with impulse noise, we propose an efficient preprocessing step for the computation of the weight function w. In all the applications, the proposed nonlocal regularizers produce superior results over the local ones, especially in image inpainting with large missing regions. Experimental results and comparisons between the proposed nonlocal methods and the local ones are shown.

Structure-adaptive CBCT reconstruction using weighted total variation and Hessian penalties

PubMed Central

Shi, Qi; Sun, Nanbo; Sun, Tao; Wang, Jing; Tan, Shan

2016-01-01

The exposure of normal tissues to high radiation during cone-beam CT (CBCT) imaging increases the risk of cancer and genetic defects. Statistical iterative algorithms with the total variation (TV) penalty have been widely used for low dose CBCT reconstruction, with state-of-the-art performance in suppressing noise and preserving edges. However, TV is a first-order penalty and sometimes leads to the so-called staircase effect, particularly over regions with smooth intensity transition in the reconstruction images. A second-order penalty known as the Hessian penalty was recently used to replace TV to suppress the staircase effect in CBCT reconstruction at the cost of slightly blurring object edges. In this study, we proposed a new penalty, the TV-H, which combines TV and Hessian penalties for CBCT reconstruction in a structure-adaptive way. The TV-H penalty automatically differentiates the edges, gradual transition and uniform local regions within an image using the voxel gradient, and adaptively weights TV and Hessian according to the local image structures in the reconstruction process. Our proposed penalty retains the benefits of TV, including noise suppression and edge preservation. It also maintains the structures in regions with gradual intensity transition more successfully. A majorization-minimization (MM) approach was designed to optimize the objective energy function constructed with the TV-H penalty. The MM approach employed a quadratic upper bound of the original objective function, and the original optimization problem was changed to a series of quadratic optimization problems, which could be efficiently solved using the Gauss-Seidel update strategy. We tested the reconstruction algorithm on two simulated digital phantoms and two physical phantoms. Our experiments indicated that the TV-H penalty visually and quantitatively outperformed both TV and Hessian penalties. PMID:27699100

Structure-adaptive CBCT reconstruction using weighted total variation and Hessian penalties.

PubMed

Shi, Qi; Sun, Nanbo; Sun, Tao; Wang, Jing; Tan, Shan

2016-09-01

The exposure of normal tissues to high radiation during cone-beam CT (CBCT) imaging increases the risk of cancer and genetic defects. Statistical iterative algorithms with the total variation (TV) penalty have been widely used for low dose CBCT reconstruction, with state-of-the-art performance in suppressing noise and preserving edges. However, TV is a first-order penalty and sometimes leads to the so-called staircase effect, particularly over regions with smooth intensity transition in the reconstruction images. A second-order penalty known as the Hessian penalty was recently used to replace TV to suppress the staircase effect in CBCT reconstruction at the cost of slightly blurring object edges. In this study, we proposed a new penalty, the TV-H, which combines TV and Hessian penalties for CBCT reconstruction in a structure-adaptive way. The TV-H penalty automatically differentiates the edges, gradual transition and uniform local regions within an image using the voxel gradient, and adaptively weights TV and Hessian according to the local image structures in the reconstruction process. Our proposed penalty retains the benefits of TV, including noise suppression and edge preservation. It also maintains the structures in regions with gradual intensity transition more successfully. A majorization-minimization (MM) approach was designed to optimize the objective energy function constructed with the TV-H penalty. The MM approach employed a quadratic upper bound of the original objective function, and the original optimization problem was changed to a series of quadratic optimization problems, which could be efficiently solved using the Gauss-Seidel update strategy. We tested the reconstruction algorithm on two simulated digital phantoms and two physical phantoms. Our experiments indicated that the TV-H penalty visually and quantitatively outperformed both TV and Hessian penalties.

Associations between dental knowledge, source of dental knowledge and oral health behavior in Japanese university students: A cross-sectional study

PubMed Central

Taniguchi-Tabata, Ayano; Mizutani, Shinsuke; Yamane-Takeuchi, Mayu; Kataoka, Kota; Azuma, Tetsuji; Tomofuji, Takaaki; Iwasaki, Yoshiaki; Morita, Manabu

2017-01-01

The aim of this study was to investigate the associations between dental knowledge, the source of dental knowledge and oral health behavior in a group of students at a university in Japan. A total of 2,220 university students (1,276 males, 944 females) volunteered to undergo an oral examination and answer a questionnaire. The questionnaire assessed dental knowledge, the source of dental knowledge and oral health behavior (e.g., daily frequency of tooth brushing, use of dental floss and regular dental checkups). The odds ratio and 95% confidence interval for oral health behavior based on dental knowledge and source of dental knowledge were calculated using logistic regression models. Of the participants, 1,266 (57.0%) students obtained dental knowledge from dental clinics, followed by school (39.2%) and television (29.1%). Logistic regression analyses indicated that use of dental floss was significantly associated with source of dental knowledge from dental clinics (P = 0.006). Receiving regular dental checkups was significantly associated with source of dental knowledge; the positive source was dental clinic (P < 0.001) and the negative sources were school (P = 0.004) and television (P = 0.018). Dental clinic was the most common source of dental knowledge and associated with better oral health behavior among the Japanese university students in this study. PMID:28594914

A Touch of...Class!

ERIC Educational Resources Information Center

Tweedie, Karen, Ed.

1987-01-01

Games for use in the second-language classroom are suggested, including variations on tic-tac-toe and snakes and ladders, races, board games based on American television programs, math activities, and a classroom mystery. (MSE)

The benefits of hearing aids and closed captioning for television viewing by older adults with hearing loss.

PubMed

Gordon-Salant, Sandra; Callahan, Julia S

2009-08-01

Although watching television is a common leisure activity of older adults, the ability to understand televised speech may be compromised by age-related hearing loss. Two potential assistive devices for improving television viewing are hearing aids (HAs) and closed captioning (CC), but their use and benefit by older adults with hearing loss are unknown. The primary purpose of this initial investigation was to determine if older hearing-impaired adults show improvements in understanding televised speech with the use of these two assistive devices (HAs and CC) compared with conditions without these devices. A secondary purpose was to examine the frequency of HA and CC use among a sample of older HA wearers. The investigation entailed a randomized, repeated-measures design of 15 older adults (59 to 82 yr) with bilateral sensorineural hearing losses who wore HAs. Participants viewed three types of televised programs (news, drama, and game show) that were each edited into lists of speech segments and provided an identification response. Each participant was tested in four conditions: baseline (no HA or CC), HA only, CC only, and HA + CC. Also, pilot testing with young normal-hearing listeners was conducted to establish list equivalence and stimulus intelligibility with a control group. All testing was conducted in a quiet room to simulate a living room, using a 20 in flat screen television. Questionnaires were also administered to participants to determine the frequency of HA and CC use while watching television. A significant effect of viewing condition was observed for all programs. Participants exhibited significantly better speech recognition scores in conditions with CC than those without CC (p < 0.01). Use of personal HAs did not significantly improve recognition of televised speech compared with the unaided condition. The condition effect was similar across the three different programs. Most of the participants (73%) regularly wore their HAs while watching television; very few of them (13%) had ever used CC. On average, use of CC while watching television dramatically improved speech understanding by a sample of older hearing-impaired adults compared with conditions without CC, including when HAs were worn.

An image-guided radiotherapy decision support framework incorporating a Bayesian network and visualization tool.

PubMed

Hargrave, Catriona; Deegan, Timothy; Bednarz, Tomasz; Poulsen, Michael; Harden, Fiona; Mengersen, Kerrie

2018-05-17

To describe a Bayesian network (BN) and complementary visualization tool that aim to support decision-making during online cone-beam computed tomography (CBCT)-based image-guided radiotherapy (IGRT) for prostate cancer patients. The BN was created to represent relationships between observed prostate, proximal seminal vesicle (PSV), bladder and rectum volume variations, an image feature alignment score (FAS TV _ OAR ), delivered dose, and treatment plan compliance (TPC). Variables influencing tumor volume (TV) targeting accuracy such as intrafraction motion, and contouring and couch shift errors were also represented. A score of overall TPC (FAS global ) and factors such as image quality were used to inform the BN output node providing advice about proceeding with treatment. The BN was quantified using conditional probabilities generated from published studies, FAS TV _ OAR /global modeling, and a survey of IGRT decision-making practices. A new IGRT visualization tool (IGRT REV ), in the form of Mollweide projection plots, was developed to provide a global summary of residual errors after online CBCT-planning CT registration. Sensitivity and scenario analyses were undertaken to evaluate the performance of the BN and the relative influence of the network variables on TPC and the decision to proceed with treatment. The IGRT REV plots were evaluated in conjunction with the BN scenario testing, using additional test data generated from retrospective CBCT-planning CT soft-tissue registrations for 13/36 patients whose data were used in the FAS TV _ OAR /global modeling. Modeling of the TV targeting errors resulted in a very low probability of corrected distances between the CBCT and planning CT prostate or PSV volumes being within their thresholds. Strength of influence evaluation with and without the BN TV targeting error nodes indicated that rectum- and bladder-related network variables had the highest relative importance. When the TV targeting error nodes were excluded from the BN, TPC was sensitive to observed PSV and rectum variations while the decision to treat was sensitive to observed prostate and PSV variations. When root nodes were set so the PSV and rectum variations exceeded thresholds, the probability of low TPC increased to 40%. Prostate and PSV variations exceeding thresholds increased the likelihood of repositioning or repeating patient preparation to 43%. Scenario testing using the test data from 13 patients, demonstrated two cases where the BN provided increased high TPC probabilities, despite some of the prostate and PSV volume variation metrics not being within tolerance. The IGRT REV tool was effective in highlighting and quantifying where TV and OAR variations occurred, supporting the BN recommendation to reposition the patient or repeat their bladder and bowel preparation. In another case, the IGRT REV tool was also effective in highlighting where PSV volume variation significantly exceeded tolerance when the BN had indicated to proceed with treatment. This study has demonstrated that both the BN and IGRT REV plots are effective tools for inclusion in a decision support system for online CBCT-based IGRT for prostate cancer patients. Alternate approaches to modeling TV targeting errors need to be explored as well as extension of the BN to support offline IGRT decisions related to adaptive radiotherapy. © 2018 American Association of Physicists in Medicine.

Information management for clinicians.

PubMed

Mehta, Neil B; Martin, Stephen A; Maypole, Jack; Andrews, Rebecca

2016-08-01

Clinicians are bombarded with information daily by social media, mainstream television news, e-mail, and print and online reports. They usually do not have much control over these information streams and thus are passive recipients, which means they get more noise than signal. Accessing, absorbing, organizing, storing, and retrieving useful medical information can improve patient care. The authors outline how to create a personalized stream of relevant information that can be scanned regularly and saved so that it is readily accessible. Copyright © 2016 Cleveland Clinic.

Should image rotation be addressed during routine cone-beam CT quality assurance?

NASA Astrophysics Data System (ADS)

Ayan, Ahmet S.; Lin, Haibo; Yeager, Caitlyn; Deville, Curtiland; McDonough, James; Zhu, Timothy C.; Anderson, Nathan; Bar Ad, Voichita; Lu, Hsiao-Ming; Both, Stefan

2013-02-01

The purpose of this study is to investigate whether quality assurance (QA) for cone-beam computed tomography (CBCT) image rotation is necessary in order to ensure the accuracy of CBCT based image-guided radiation therapy (IGRT) and adaptive radiotherapy (ART). Misregistration of angular coordinates during CBCT acquisition may lead to a rotated reconstructed image. If target localization is performed based on this image, an under- or over-dosage of the target volume (TV) and organs at risk (OARs) may occur. Therefore, patient CT image sets were rotated by 1° up to 3° and the treatment plans were recalculated to quantify changes in dose-volume histograms. A computer code in C++ was written to model the TV displacement and overlap area of an ellipse shape at the target and dose prescription levels corresponding to the image rotation. We investigated clinical scenarios in IGRT and ART in order to study the implications of image rotation on dose distributions for: (1) lateral TV and isocenter (SBRT), (2) central TV and isocenter (IMRT), (3) lateral TV and isocenter (IMRT). Mathematical analysis showed the dose coverage of TV depends on its shape, size, location, and orientation relative to the isocenter. Evaluation of three first scenario for θ = 1° showed variations in TV D95 in the context of IGRT and ART when compared to the original plan were within 2.7 ± 2.6% and 7.7 ± 6.9% respectively while variations in the second and third scenarios were less significant (<0.5%) for the angular range evaluated. However a larger degree of variation was found in terms of minimum and maximum doses for target and OARs. The rotation of CBCT image data sets may have significant dosimetric consequences in IGRT and ART. The TV's location relative to isocenter and shape determine the extent of alterations in dose indicators. Our findings suggest that a CBCT QA criterion of 1° would be a reasonable action level to ensure accurate dose delivery.

Messages of distinction: the HIV/AIDS media campaign in Thailand.

PubMed

Lyttleton, C

1996-03-01

In predominantly rural Thailand, television is a primary source of HIV/AIDS knowledge. Since 1990, HIV/AIDS warning messages have been aired regularly and repeatedly on television as part of the national strategy to minimize transmission of HIV. The education and prevention messages chosen do more than suggest measures to avoid infection. Within a logic of risk, these messages also define characteristics of people who are signified as threatening agents of infection. In Thailand, prostitutes and drug users are portrayed as the feared Other. Because commercial sex is so widespread, the demarcation of prostitutes as a high risk group signals a diffuse threat not easily subject to conceptual distancing. It is the pervasive and often fear-based associations born of the media material that, in large part, establish the basis for emergent practice when thoughts or actions are triggered by consideration of HIV/AIDS.

Antismoking television advertising and socioeconomic variations in calls to Quitline.

PubMed

Siahpush, Mohammad; Wakefield, Melanie; Spittal, Matt; Durkin, Sarah

2007-04-01

To assess the socioeconomic variations in call rates to the Quitline (Victoria, Australia) and in the impact of anti-tobacco television advertising on call rates. The outcome measure was the number of calls to the Quitline in Victoria for each week for each socioeconomic group for the period January 2001 to March 2004. Socioeconomic status (SES) was derived from the caller's postcode using the Index of Socioeconomic Disadvantage provided by the Australian Bureau of Statistics. The exposure measure was weekly Target Audience Rating Points (TARPs, a standard measure of television advertising weight) for anti-tobacco advertising broadcast in Victoria over the same period. Negative binomial regression was used to examine the interaction of SES and TARPs in their effect on the number of Quitline calls. SES and call rates were positively associated. Adjusted call rate was 57% (95% CI 45% to 69%) higher in the highest than the lowest SES quintile. SES differences in call rates were stable over time. In the study period, the effect of the presence or increasing levels of antismoking TARPs on call rates did not vary across categories of SES. In the study period, different SES groups had a similar level of responsiveness to antismoking television advertisements, at least as measured by the rate of calls to the Quitline. However, the present media campaigns are not likely to diminish SES differences in call rates, and more needs to be done to encourage disadvantaged groups to call the Quitline.

Antismoking television advertising and socioeconomic variations in calls to Quitline

PubMed Central

Siahpush, Mohammad; Wakefield, Melanie; Spittal, Matt; Durkin, Sarah

2007-01-01

Objective To assess the socioeconomic variations in call rates to the Quitline (Victoria, Australia) and in the impact of anti‐tobacco television advertising on call rates. Design The outcome measure was the number of calls to the Quitline in Victoria for each week for each socioeconomic group for the period January 2001 to March 2004. Socioeconomic status (SES) was derived from the caller's postcode using the Index of Socioeconomic Disadvantage provided by the Australian Bureau of Statistics. The exposure measure was weekly Target Audience Rating Points (TARPs, a standard measure of television advertising weight) for anti‐tobacco advertising broadcast in Victoria over the same period. Negative binomial regression was used to examine the interaction of SES and TARPs in their effect on the number of Quitline calls. Results SES and call rates were positively associated. Adjusted call rate was 57% (95% CI 45% to 69%) higher in the highest than the lowest SES quintile. SES differences in call rates were stable over time. In the study period, the effect of the presence or increasing levels of antismoking TARPs on call rates did not vary across categories of SES. Conclusions In the study period, different SES groups had a similar level of responsiveness to antismoking television advertisements, at least as measured by the rate of calls to the Quitline. However, the present media campaigns are not likely to diminish SES differences in call rates, and more needs to be done to encourage disadvantaged groups to call the Quitline. PMID:17372288

Benefits of an exercise wellness program after spinal cord injury.

PubMed

Crane, Deborah A; Hoffman, Jeanne M; Reyes, Maria R

2017-03-01

To describe the initial benefits of a structured group exercise program on exercise frequency and intensity, perceived health, pain, mood, and television watching habits. Pre-test/post-test. Eighty-nine persons with SCI participated voluntarily in a no-cost, twice weekly physical therapy group exercise class over 3 months. Forty-five persons completed pre- and post-participation interviews on exercise frequency and intensity, perceived health, pain, mood, sleep, and television watching habits. Mean participant age of the respondents was 43.82 years. 49% had AIS C or D injuries, 24% had AIS A,B paraplegia, 9% had AIS A,B C1-C4 and 18% had AIS A,B C5-C8. 75.6% of participants were male and 84.4% had a traumatic etiology as the cause of their SCI. There was a significant improvement in days of strenuous and moderate exercise as well as health state. There was an average decrease in pain scores, depression scores, number of hours spent watching television, and days/week of mild exercise. Participation in structured, small group exercise as a component of a wellness program after SCI shows promise for improving regular exercise participation and health state, but benefits may also occur across other areas of health and function including mood, pain, and hours spent watching television. Further follow-up is needed to determine whether improvements can be maintained after program completion and across all neurological levels.

Impact of tobacco control policies and mass media campaigns on monthly adult smoking prevalence.

PubMed

Wakefield, Melanie A; Durkin, Sarah; Spittal, Matthew J; Siahpush, Mohammad; Scollo, Michelle; Simpson, Julie A; Chapman, Simon; White, Victoria; Hill, David

2008-08-01

We sought to assess the impact of several tobacco control policies and televised antismoking advertising on adult smoking prevalence. We used a population survey in which smoking prevalence was measured each month from 1995 through 2006. Time-series analysis assessed the effect on smoking prevalence of televised antismoking advertising (with gross audience rating points [GRPs] per month), cigarette costliness, monthly sales of nicotine replacement therapy (NRT) and bupropion, and smoke-free restaurant laws. Increases in cigarette costliness and exposure to tobacco control media campaigns significantly reduced smoking prevalence. We found a 0.3-percentage-point reduction in smoking prevalence by either exposing the population to televised antismoking ads an average of almost 4 times per month (390 GRPs) or by increasing the costliness of a pack of cigarettes by 0.03% of gross average weekly earnings. Monthly sales of NRT and bupropion, exposure to NRT advertising, and smoke-free restaurant laws had no detectable impact on smoking prevalence. Increases in the real price of cigarettes and tobacco control mass media campaigns broadcast at sufficient exposure levels and at regular intervals are critical for reducing population smoking prevalence.

Impact of Tobacco Control Policies and Mass Media Campaigns on Monthly Adult Smoking Prevalence

PubMed Central

Wakefield, Melanie A.; Durkin, Sarah; Spittal, Matthew J.; Siahpush, Mohammad; Scollo, Michelle; Simpson, Julie A.; Chapman, Simon; White, Victoria; Hill, David

2008-01-01

Objectives. We sought to assess the impact of several tobacco control policies and televised antismoking advertising on adult smoking prevalence. Methods. We used a population survey in which smoking prevalence was measured each month from 1995 through 2006. Time-series analysis assessed the effect on smoking prevalence of televised antismoking advertising (with gross audience rating points [GRPs] per month), cigarette costliness, monthly sales of nicotine replacement therapy (NRT) and bupropion, and smoke-free restaurant laws. Results. Increases in cigarette costliness and exposure to tobacco control media campaigns significantly reduced smoking prevalence. We found a 0.3-percentage-point reduction in smoking prevalence by either exposing the population to televised antismoking ads an average of almost 4 times per month (390 GRPs) or by increasing the costliness of a pack of cigarettes by 0.03% of gross average weekly earnings. Monthly sales of NRT and bupropion, exposure to NRT advertising, and smoke-free restaurant laws had no detectable impact on smoking prevalence. Conclusions. Increases in the real price of cigarettes and tobacco control mass media campaigns broadcast at sufficient exposure levels and at regular intervals are critical for reducing population smoking prevalence. PMID:18556601

HDTV and large-screen display

NASA Astrophysics Data System (ADS)

Mitsuhashi, Tetsuo

1990-08-01

HDTV (known as Hi-Vision in Japan), with its ability to provide through high- definition pictures on a large screen display advanced psychological effects such as sensations of reality and a visual impact unobtainable in conventional television, is the television system of the next generation. In Japan, daily one-hour experimental broadcasting was initiated in June 1989 using the BS-2 broadcast satellite, and regular service is scheduled to begin via the BS-3 satellite to be launched in 1990. To this end, a home-use receiver using VLSIs has already been developed. Moreover, HDTV is currently being applied in such diverse areas as film production, printing and publishing, medicine, and art museums. The HDTV system handles approximately five times the information of conventional television. As a result, a large screen display capable of maintaining stable resolution greater than twice that of conventional displays is essential to the full realization of HDTV's vast potential. This paper will first discuss HDTV's basic parameters, concentrating on the psychovisual effects, and explain some preferable display characteristics from this psychovisual point of view. It will then discuss the technical problems in developing such a display, and final ly describe the current state of HDTV display development.

Nutritional status and the influence of TV consumption on female body size ideals in populations recently exposed to the media.

PubMed

Jucker, Jean-Luc; Thornborrow, Tracey; Beierholm, Ulrik; Burt, D Michael; Barton, Robert A; Evans, Elizabeth H; Jamieson, Mark A; Tovée, Martin J; Boothroyd, Lynda G

2017-08-16

Television consumption influences perceptions of attractive female body size. However, cross-cultural research examining media influence on body ideals is typically confounded by differences in the availability of reliable and diverse foodstuffs. 112 participants were recruited from 3 Nicaraguan villages that differed in television consumption and nutritional status, such that the contribution of both factors could be revealed. Participants completed a female figure preference task, reported their television consumption, and responded to several measures assessing nutritional status. Communities with higher television consumption and/or higher nutritional status preferred thinner female bodies than communities with lower television consumption and/or lower nutritional status. Bayesian mixed models estimated the plausible range of effects for television consumption, nutritional status, and other relevant variables on individual preferences. The model explained all meaningful differences between our low-nutrition villages, and television consumption, after sex, was the most likely of these predictors to contribute to variation in preferences (probability mass >95% when modelling only variables with zero-order associations with preferences, but only 90% when modelling all possible predictors). In contrast, we found no likely link with nutritional status. We thus found evidence that where media access and nutritional status are confounded, media is the more likely predictor of body ideals.

Serial-to-parallel color-TV converter

NASA Technical Reports Server (NTRS)

Doak, T. W.; Merwin, R. B.; Zuckswert, S. E.; Sepper, W.

1976-01-01

Solid analog-to-digital converter eliminates flicker and problems with time base stability and gain variation in sequential color TV cameras. Device includes 3-bit delta modulator; two-field memory; timing, switching, and sync network; and three 3-bit delta demodulators

[Extracurricular activities of adolescents useful for smoking prevention programs. OCTOPUS team].

PubMed

López González, M L; López, T; Comas Fuentes, A; Herrero Puente, P; González Blázquez, J; Cueto Espinar, A; Thomas, H; Douglas, J; Markham, W; Charlton, A; de Vries, H; Leijs, I; Mester, I; Ausems, M

1999-01-01

The cigarette smoking habit continues to be prevalent to a greater degree than would be desirable among teenagers. Innovative prevention programs are needed. This descriptive cross-sectional study sets out the behavior variables related to the cigarette smoking habit and the extracurricular activities in which teenagers are most frequently involved which are useful for setting out extracurricular prevention programs. The data was collected by means of a questionnaire validated in a representative sample of school age youths (ages 10-11 and 13-14) from Asturias. The variables entailed in cigarette smoking were analyzed using the regression method. The starting smoker percentage is 14.5%-42.5%, regular smokers totaling 1.1% and 12.4%, respectively. Two models were constructed with the variables significantly related to smoking behavior, which are properly classified into smoker/non-smoker by 98.85% and 91.39% of the children, by ages. The environmental variables (availability of cigarettes and alcoholic beverages and regular visits to places entailing risk) are the major aspects comprising the model. The most common extracurricular activities are: watching TV, reading and listening to music and watching or playing sports. The findings provide keys to planning extracurricular activities tailored to fit in with the activities most popular among teens: TV commercials and ads on music media (CD's, tapes, etc.) and printed information mailed directly to teens at their homes, with messages conveyed by opinion-leaders among teens in the fields of sports, music and television.

The benefits of hearing aids and closed captioning for television viewing by older adults with hearing loss

PubMed Central

Gordon-Salant, Sandra; Callahan, Julia S.

2010-01-01

Objectives Although watching television is a common leisure activity of older adults, the ability to understand televised speech may be compromised by age-related hearing loss. Two potential assistive devices for improving television viewing are hearing aids and closed captioning, but their use and benefit by older adults with hearing loss are unknown. The primary purpose of this initial investigation was to determine if older hearing-impaired adults show improvements in understanding televised speech with the use of these two assistive devices (hearing aids and closed captioning) compared to conditions without these devices. A secondary purpose was to examine the frequency of hearing aid use and closed captioning use among a sample of older hearing aid wearers. Design The investigation entailed a randomized, repeated-measures design of 15 older adults (59–82 years) with bilateral sensorineural hearing losses who wore hearing aids. Participants viewed three types of televised programs (news, drama, game show) that were each edited into lists of speech segments, and provided an identification response. Each participant was tested in four conditions: baseline (no hearing aids or closed captioning), hearing aids only, closed captioning only, and hearing aids + closed captioning. Pilot testing with young normal-hearing listeners was conducted also to establish list equivalence and stimulus intelligibility with a control group. All testing was conducted in a quiet room to simulate a living room, using a 19-in flat screen television. Questionnaires were also administered to participants to determine frequency of hearing aid use and closed captioning use while watching television. Results A significant effect of viewing condition was observed for all programs. Participants exhibited significantly better speech recognition scores in conditions with closed captioning than those without closed captioning (p<.01). Use of personal hearing aids did not significantly improve recognition of televised speech compared to the unaided condition. The condition effect was similar across the three different programs. Most of the participants (73%) regularly wore their hearing aids while watching television; very few of them (13%) had ever used closed captioning. Conclusions On average, use of closed captioning while watching television dramatically improved speech understanding by a sample of older hearing-impaired adults compared to conditions without closed captioning, including when hearing aids were worn. PMID:19444122

Analysis of food advertising to children on Spanish television: probing exposure to television marketing

PubMed Central

Campos, Daniel; Hernández-Torres, Juan José; Agil, Ahmad; Comino, Mariano; López, Juan Carlos; Macías, Victoria

2016-01-01

Introduction We aimed to assess longitudinal changes in television (TV) food advertising during 2013 compared to 2007, measuring children's exposure to healthy and unhealthy advertisements, after the new European and Spanish Public Health laws published in 2011. Material and methods Two thematic channels for children (TC), and 2 generalist channels (GC) for all ages were recorded, between April and May 2013, on 2 week and 2 weekend days. Food advertisements were classified as core (CFA) (nutrient dense, low energy), non-core (NCFA) (unbalanced energy profile or high in energy), or others (OFA) (supermarkets and special food). Results One thousand two hundred sixty-three food advertisements were recorded (TC: 579/GC: 684) in 2013. NCFA were the most shown (54.9%) in the regular full day TV programming (p < 0.001). In 2013, children watching GC had a higher relative risk of being exposed to fast food advertisements than when watching TC (RR = 2.133, 95% CI: 1.398–3.255); CFA were broadcast most frequently in 2013 (GC: 23.7%; and TC: 47.2%) vs. 2007 (TC: 22.9%) (p < 0.001). The proportion of broadcasting between NCFA/CFA and OFA food advertisements in children's peak time slots was higher on TC (203/162) during 2013 than on GC (189/140), and significantly higher than that shown on TC in 2007 (180/36, p < 0.001). Conclusions Broadcasting of unhealthy TV food advertising on TC is lower today than six years ago; but, children's exposure to TV advertising of unhealthy food is worrying in Spain, and there is more exposure to unhealthy than healthy food by TV. Watching GC in 2013 had higher risk of being exposed to fast food advertisements than watching TC. PMID:27478462

Analysis of food advertising to children on Spanish television: probing exposure to television marketing.

PubMed

Campos, Daniel; Hernández-Torres, Juan José; Agil, Ahmad; Comino, Mariano; López, Juan Carlos; Macías, Victoria; Campoy, Cristina

2016-08-01

We aimed to assess longitudinal changes in television (TV) food advertising during 2013 compared to 2007, measuring children's exposure to healthy and unhealthy advertisements, after the new European and Spanish Public Health laws published in 2011. Two thematic channels for children (TC), and 2 generalist channels (GC) for all ages were recorded, between April and May 2013, on 2 week and 2 weekend days. Food advertisements were classified as core (CFA) (nutrient dense, low energy), non-core (NCFA) (unbalanced energy profile or high in energy), or others (OFA) (supermarkets and special food). One thousand two hundred sixty-three food advertisements were recorded (TC: 579/GC: 684) in 2013. NCFA were the most shown (54.9%) in the regular full day TV programming (p < 0.001). In 2013, children watching GC had a higher relative risk of being exposed to fast food advertisements than when watching TC (RR = 2.133, 95% CI: 1.398-3.255); CFA were broadcast most frequently in 2013 (GC: 23.7%; and TC: 47.2%) vs. 2007 (TC: 22.9%) (p < 0.001). The proportion of broadcasting between NCFA/CFA and OFA food advertisements in children's peak time slots was higher on TC (203/162) during 2013 than on GC (189/140), and significantly higher than that shown on TC in 2007 (180/36, p < 0.001). Broadcasting of unhealthy TV food advertising on TC is lower today than six years ago; but, children's exposure to TV advertising of unhealthy food is worrying in Spain, and there is more exposure to unhealthy than healthy food by TV. Watching GC in 2013 had higher risk of being exposed to fast food advertisements than watching TC.

Explicit Filtering Based Low-Dose Differential Phase Reconstruction Algorithm with the Grating Interferometry.

PubMed

Jiang, Xiaolei; Zhang, Li; Zhang, Ran; Yin, Hongxia; Wang, Zhenchang

2015-01-01

X-ray grating interferometry offers a novel framework for the study of weakly absorbing samples. Three kinds of information, that is, the attenuation, differential phase contrast (DPC), and dark-field images, can be obtained after a single scanning, providing additional and complementary information to the conventional attenuation image. Phase shifts of X-rays are measured by the DPC method; hence, DPC-CT reconstructs refraction indexes rather than attenuation coefficients. In this work, we propose an explicit filtering based low-dose differential phase reconstruction algorithm, which enables reconstruction from reduced scanning without artifacts. The algorithm adopts a differential algebraic reconstruction technique (DART) with the explicit filtering based sparse regularization rather than the commonly used total variation (TV) method. Both the numerical simulation and the biological sample experiment demonstrate the feasibility of the proposed algorithm.

Explicit Filtering Based Low-Dose Differential Phase Reconstruction Algorithm with the Grating Interferometry

PubMed Central

Zhang, Li; Zhang, Ran; Yin, Hongxia; Wang, Zhenchang

2015-01-01

X-ray grating interferometry offers a novel framework for the study of weakly absorbing samples. Three kinds of information, that is, the attenuation, differential phase contrast (DPC), and dark-field images, can be obtained after a single scanning, providing additional and complementary information to the conventional attenuation image. Phase shifts of X-rays are measured by the DPC method; hence, DPC-CT reconstructs refraction indexes rather than attenuation coefficients. In this work, we propose an explicit filtering based low-dose differential phase reconstruction algorithm, which enables reconstruction from reduced scanning without artifacts. The algorithm adopts a differential algebraic reconstruction technique (DART) with the explicit filtering based sparse regularization rather than the commonly used total variation (TV) method. Both the numerical simulation and the biological sample experiment demonstrate the feasibility of the proposed algorithm. PMID:26089971

Vulnerability to the impact of temperature variability on mortality in 31 major Chinese cities.

PubMed

Yang, Jun; Zhou, Maigeng; Li, Mengmeng; Liu, Xiaobo; Yin, Peng; Sun, Qinghua; Wang, Jun; Wu, Haixia; Wang, Boguang; Liu, Qiyong

2018-08-01

Few studies have analyzed the health effects of temperature variability (TV) accounting for both interday and intraday variations in ambient temperature. In this study, TV was defined as the standard deviations of the daily minimum and maximum temperature during different exposure days. Distributed lag non-linear Poisson regression model was used to examine the city-specific effect of TV on mortality in 31 Chinese municipalities and provincial capital cities. The national estimate was pooled through a meta-analysis based on the restricted maximum likelihood estimation. To assess effect modification on TV-mortality association by individual characteristics, stratified analyses were further fitted. Potential effect modification by city characteristics was performed through a meta-regression analysis. In total, 259 million permanent residents and 4,481,090 non-accidental deaths were covered in this study. The effect estimates of TV on mortality were generally increased by longer exposure days. A 1 °C increase in TV at 0-7 days' exposure was associated with a 0.60% (95% CI: 0.25-0.94%), 0.65% (0.24-1.05%), 0.82% (0.29-1.36%), 0.86% (0.42-1.31%), 0.98% (0.57-1.39%) and 0.54% (-0.11-1.20%) increase in non-accidental, cardiovascular, IHD, stroke, respiratory and COPD mortalities, respectively. Those with lower levels of educational attainment were significantly susceptible to TV. Cities with dense population, higher mean temperatures, and relative humidity and lower diurnal temperature ranges also had higher mortality risks caused by TV. This study demonstrated that TV had considerable health effects. An early warning system to alert residents about large temperature variations is recommended, which may have a significant impact on the community awareness and public health. Copyright © 2018 Elsevier Ltd. All rights reserved.

Determinants of Network News Coverage of the Oil Industry during the Late 1970s.

ERIC Educational Resources Information Center

Erfle, Stephen; McMillan, Henry

1989-01-01

Examines which firms and products best predict media coverage of the oil industry. Reports that price variations in testing oil and gasoline correlate with the extent of news coverage provided by network television. (MM)

[Metabolic functions and sport].

PubMed

Riviere, Daniel

2004-01-01

Current epidemiological studies emphasize the increased of metabolic diseases of the adults, such as obesity, type-2 diabetes and metabolic syndromes. Even more worrying is the rising prevalence of obesity in children. It is due more to sedentariness, caused more by inactivity (television, video, games, etc.) than by overeating. Many studies have shown that regular physical activities benefit various bodily functions including metabolism. After dealing with the major benefits of physical exercise on some adult metabolic disorders, we focus on the prime role played by physical activity in combating the public health problem of childhood obesity.

Media use as a reason for meal skipping and fast eating in secondary school children.

PubMed

Van den Bulck, J; Eggermont, S

2006-04-01

This study examined self-reported meal skipping and eating faster than usual with the goal of watching television or playing computer games. Respondents reported their media use and indicated how often they skipped a meal to watch a favourite television programme or to play a computer game, and how often they ate faster than usual in order to watch television or play a computer game. Respondents were 2546 adolescents of 13 (first year of secondary school) and 16 years (fourth year of secondary school) of age. About one respondent in 10 skipped at least one meal every week for either television viewing or computer game playing. Weekly meal skipping for television viewing occurs more regularly in boys and first-year students, but particularly in teenagers who view 5 h or more daily (15% of the sample). The category of teenagers who play computer games four times a week or more (25.3% of the sample) is at increased risk of meal skipping; those who play more than four times a week are 10 times more likely weekly to skip a meal. A quarter of the adolescents eat faster at least once a week to be able to watch television or play a computer game. Regardless of gender and school year, teenagers' risk of eating faster progressively increases with their use of the media. Those who watch 4 h or more daily are about seven times more likely to skip a meal for television and those who play computer games at least four times a week are nine times more likely weekly to skip a meal. Unhealthy eating habits can be a side effect of heavy or excessive media use. Teenagers' use of television or game computers during nonworking or out-of-school hours partly displaces the amount of time that needs to be spent at meals. Practitioners and educators may try to encourage or restore a pattern of healthful meal consumption habits by reducing the amount of media use, and by supporting parental rule-making regarding children's eating habits and media use.

Catalogue of Main Characteristics of Pulsations of 173 Semi-Regular Stars

NASA Astrophysics Data System (ADS)

Chinarova, L. L.; Andronov, I. L.

2000-12-01

The characteristics of brightness variations of 173 semi-regular stars are tabulated: the moments and brightness of the extrema; the effective periods, amplitudes and significance obtained by using different methods: a) the periodogram analysis (harmonic least squares t) with prewhitening to determine characteristics and significance of waves with 3 periods; b) the wavelet analysis to determine characteristics of statistically significant waves; ) the "running parabola" scalegram analysis to determine the optimal filter half - width for smoothing. The characteristics may be used for more precise classification of semi-regular variables. Characteristics of the 6509 extrema of 147 stars are listed. The electronic version is available via http://ila.webjump.om. The observations for the analysis have been taken from the AFOEV and VSOLJ databases (with a duration up to 94 years) for the stars: AQ, EH, EK, RS, RU, RV, ST, TV, TY, TZ, UX, VX And; GY, PX, S, V, V844 Aql; V, Z Aqr; T Ari; AG, RS, S, UU, Z Aur; RV, RW, RX, RZ, U, V, WY Boo; T Cae; RR, RS, RY, S, ST, U Cam; RT Cap; PZ, SV, UX, V393, V465, WZ Cas; T, Y Cen; AR, RU, RW, RX, SS, TY, W Cep; T Cet; RS, RT, T, X Cnc; RR, RS, TT CrB; V, Y Cvn; AA, AF, AI, AV, AW, BC, RS, RU, RV, RW, RZ, TT, V460, W Cyg; EU, U Del; RS, RY, S, TX, UX, WZ Dra; SY, Z Eri; IS, NQ, RS, SW, TU, TV, Y Gem; DE, MZ, RR, ST, SX, UU, X Her; FF, RT, U, V, W, Y Hya; RS Lac; RY, SX Leo; RX, S Lep; U, W LMi; Y, EG, R, SZ Lyr; RV, SW, X Mon; V759 Oph; BQ, FX, GT, RT, W Ori; AF, AK, SV, TX Peg; AD, BU, DY, FZ, RS, RU, S, SU, SY, T, UZ, W, XX Per; R Pic; RT, RW, Z Psc; BM Sco; S Sct; FG Ser; X Sge; AB, TT, W, Y Tau; W Tri; RX, RY, RZ, ST,SV, V, Y, Z UMa; R, V UMi; RT, SS, SW Vir; RU Vul.

Genre-Specific Cultivation Effects: Lagged Associations between Overall TV Viewing, Local TV News Viewing, and Fatalistic Beliefs about Cancer Prevention

PubMed Central

Niederdeppe, Jeff

2014-01-01

Cultivation theory and research has been criticized for its failure to consider variation in effects by genre, employ appropriate third-variable controls, and determine causal direction. Recent studies, controlling for a variety of demographic characteristics and media use variables, have found that exposure to local television (TV) newscasts is associated with a variety of problematic “real-world” beliefs. However, many of these studies have not adequately assessed causal direction. Redressing this limitation, we analyzed data from a two-wave national representative survey which permitted tests of lagged association between overall TV viewing, local TV news viewing, and fatalistic beliefs about cancer prevention. We first replicated the original cultivation effect and found a positive association between overall TV viewing at time 1 and increased fatalistic beliefs about cancer prevention at time 2. Analyses also provided evidence that local TV news viewing at time 1 predicts increased fatalistic beliefs about cancer prevention at time 2. There was little evidence for reverse causation in predicting changes in overall TV viewing or local TV news viewing. The paper concludes with a discussion of theoretical and practical implications of these findings. PMID:25605981

Connecting with Your Preteen

MedlinePlus

... up something pre-made, sit down together to eat it. Turn off the TV and try to tune out the ringing phone. If it's impossible to do every night, schedule a regular weekly family dinner night that accommodates kids' schedules. Make it something ...

Home Data Banks Turn British On

ERIC Educational Resources Information Center

Science News, 1978

1978-01-01

Describes the operation and numerous capabilities of a British computerized data retrieval system named Prestel. It provides access, through the regular telephone network and a TV screen, to computer-based information supplied by many companies, agencies and commercial outlets. (GA)

Correlates of socio-economic inequalities in women's television viewing: a study of intrapersonal, social and environmental mediators.

PubMed

Teychenne, Megan; Ball, Kylie; Salmon, Jo

2012-01-20

Socio-economically disadvantaged women are at a greater risk of spending excess time engaged in television viewing, a behavior linked to several adverse health outcomes. However, the factors which explain socio-economic differences in television viewing are unknown. This study aimed to investigate the contribution of intrapersonal, social and environmental factors to mediating socio-economic (educational) inequalities in women's television viewing. Cross-sectional data were provided by 1,554 women (aged 18-65) who participated in the 'Socio-economic Status and Activity in Women study' of 2004. Based on an ecological framework, women self-reported their socio-economic position (highest education level), television viewing, as well as a number of potential intrapersonal (enjoyment of television viewing, preference for leisure-time sedentary behavior, depression, stress, weight status), social (social participation, interpersonal trust, social cohesion, social support for physical activity from friends and from family) and physical activity environmental factors (safety, aesthetics, distance to places of interest, and distance to physical activity facilities). Multiple mediating analyses showed that two intrapersonal factors (enjoyment of television viewing and weight status) and two social factors (social cohesion and social support from friends for physical activity) partly explained the educational inequalities in women's television viewing. No physical activity environmental factors mediated educational variations in television viewing. Acknowledging the cross-sectional nature of this study, these findings suggest that health promotion interventions aimed at reducing educational inequalities in television viewing should focus on intrapersonal and social strategies, particularly providing enjoyable alternatives to television viewing, weight-loss/management information, increasing social cohesion in the neighborhood and promoting friend support for activity.

Investigation of an electronic image enhancer for radiographs

NASA Technical Reports Server (NTRS)

Vary, A.

1972-01-01

Radiographs of nuclear and aerospace components were studied with a closed-circuit television system to determine the advantages of electronic enhancement in radiographic nondestructive evaluation. The radiographic images were examined on a television monitor under various degrees of magnification and enhancement. The enhancement was accomplished by generating a video signal whose amplitude is proportional to the rate of change of density. Points, lines, edges, and other density variations that are faintly registered in the original image are rendered in sharp relief. Examples of the applications of this mode of enhancement are discussed together with the system's dynamic response and resolution.

Investigation of an electronic image enhancer for radiographs.

NASA Technical Reports Server (NTRS)

Vary, A.

1972-01-01

Radiographs of nuclear and aerospace components were studied with a closed-circuit television system to determine the advantages of electronic enhancement in radiographic nondestructive evaluation. The radiographic images were examined on a television monitor under various degrees of magnification and enhancement. The enhancement was accomplished by generating a video signal whose amplitude is proportional to the rate of change of density. Points, lines, edges, and other density variations that are faintly registered in the original image are rendered in sharp relief. Examples of the applications of this mode of enhancement are discussed together with the system's dynamic response and resolution.

Should image rotation be addressed during routine cone-beam CT quality assurance?

PubMed

Ayan, Ahmet S; Lin, Haibo; Yeager, Caitlyn; Deville, Curtiland; McDonough, James; Zhu, Timothy C; Anderson, Nathan; Bar Ad, Voichita; Lu, Hsiao-Ming; Both, Stefan

2013-02-21

The purpose of this study is to investigate whether quality assurance (QA) for cone-beam computed tomography (CBCT) image rotation is necessary in order to ensure the accuracy of CBCT based image-guided radiation therapy (IGRT) and adaptive radiotherapy (ART). Misregistration of angular coordinates during CBCT acquisition may lead to a rotated reconstructed image. If target localization is performed based on this image, an under- or over-dosage of the target volume (TV) and organs at risk (OARs) may occur. Therefore, patient CT image sets were rotated by 1° up to 3° and the treatment plans were recalculated to quantify changes in dose-volume histograms. A computer code in C++ was written to model the TV displacement and overlap area of an ellipse shape at the target and dose prescription levels corresponding to the image rotation. We investigated clinical scenarios in IGRT and ART in order to study the implications of image rotation on dose distributions for: (1) lateral TV and isocenter (SBRT), (2) central TV and isocenter (IMRT), (3) lateral TV and isocenter (IMRT). Mathematical analysis showed the dose coverage of TV depends on its shape, size, location, and orientation relative to the isocenter. Evaluation of three first scenario for θ = 1° showed variations in TV D95 in the context of IGRT and ART when compared to the original plan were within 2.7 ± 2.6% and 7.7 ± 6.9% respectively while variations in the second and third scenarios were less significant (<0.5%) for the angular range evaluated. However a larger degree of variation was found in terms of minimum and maximum doses for target and OARs. The rotation of CBCT image data sets may have significant dosimetric consequences in IGRT and ART. The TV's location relative to isocenter and shape determine the extent of alterations in dose indicators. Our findings suggest that a CBCT QA criterion of 1° would be a reasonable action level to ensure accurate dose delivery.

Accelerated high-resolution photoacoustic tomography via compressed sensing

NASA Astrophysics Data System (ADS)

Arridge, Simon; Beard, Paul; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

2016-12-01

Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining model-based, variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: first, we describe and model two general spatial sub-sampling schemes. Then, we discuss how to implement them using the FP interferometer and demonstrate the potential of these novel compressed sensing PAT devices through simulated data from a realistic numerical phantom and through measured data from a dynamic experimental phantom as well as from in vivo experiments. Our results show that images with good spatial resolution and contrast can be obtained from highly sub-sampled PAT data if variational image reconstruction techniques that describe the tissues structures with suitable sparsity-constraints are used. In particular, we examine the use of total variation (TV) regularization enhanced by Bregman iterations. These novel reconstruction strategies offer new opportunities to dramatically increase the acquisition speed of photoacoustic scanners that employ point-by-point sequential scanning as well as reducing the channel count of parallelized schemes that use detector arrays.

Ionospheric reflection coefficient for television signals

NASA Astrophysics Data System (ADS)

From, W. R.

1984-08-01

It has been shown that the ionospherically reflected field strength for 50 MHz signals varies (statistically) in proportion to about the 18th power of f(0)E(s) at the midpoint between transmitter and receiver. This note is to point out that this observation provides support for the theory that the horizontal structure of E(s) is due to a horizontal variation in the wind shear rather than horizontal convergence of metallic ions or a horizontal variation in the metallic column content.

Graph cuts for curvature based image denoising.

PubMed

Bae, Egil; Shi, Juan; Tai, Xue-Cheng

2011-05-01

Minimization of total variation (TV) is a well-known method for image denoising. Recently, the relationship between TV minimization problems and binary MRF models has been much explored. This has resulted in some very efficient combinatorial optimization algorithms for the TV minimization problem in the discrete setting via graph cuts. To overcome limitations, such as staircasing effects, of the relatively simple TV model, variational models based upon higher order derivatives have been proposed. The Euler's elastica model is one such higher order model of central importance, which minimizes the curvature of all level lines in the image. Traditional numerical methods for minimizing the energy in such higher order models are complicated and computationally complex. In this paper, we will present an efficient minimization algorithm based upon graph cuts for minimizing the energy in the Euler's elastica model, by simplifying the problem to that of solving a sequence of easy graph representable problems. This sequence has connections to the gradient flow of the energy function, and converges to a minimum point. The numerical experiments show that our new approach is more effective in maintaining smooth visual results while preserving sharp features better than TV models.

Binge Viewing, Sleep, and the Role of Pre-Sleep Arousal

PubMed Central

Exelmans, Liese; Van den Bulck, Jan

2017-01-01

Study Objectives: To investigate the prevalence of binge viewing, its association with sleep and examine arousal as an underlying mechanism of this association. Methods: Four hundred twenty-three adults (aged 18–25 years old, 61.9% female) completed an online survey assessing regular television viewing, binge viewing, sleep quality (Pittsburgh Sleep Quality Index), fatigue (Fatigue Assessment Scale), insomnia (Bergen Insomnia Scale), and pre-sleep arousal (Pre-Sleep Arousal Scale). Regression analyses were conducted. Mediation analysis was performed using PROCESS Macro. Results: There were 80.6% who identified themselves as a binge viewer. Among those who binge viewed (n = 341), 20.2% had binge viewed at least a few times a week during the past month. Among poor sleepers (Pittsburgh Sleep Quality Index > 5), 32.6% had a poor sleep quality associated with being a binge viewer. Higher binge viewing frequency was associated with a poorer sleep quality, increased fatigue and more symptoms of insomnia, whereas regular television viewing was not. Cognitive pre-sleep arousal fully mediated these relationships. Conclusions: New viewing styles such as binge viewing are increasingly prevalent and may pose a threat to sleep. Increased cognitive arousal functions as the mechanism explaining these effects. Measures of media exposure should take into account the user's level of engagement with media. Interventions aimed at (1) alerting viewers about excessive viewing duration and (2) reducing arousal before sleep may be useful ways to tackle sleep problems in binge viewers. Citation: Exelmans L, Van den Bulck J. Binge viewing, sleep, and the role of pre-sleep arousal. J Clin Sleep Med. 2017;13(8):1001–1008. PMID:28728618

Building the case for independent monitoring of food advertising on Australian television.

PubMed

King, Lesley; Hebden, Lana; Grunseit, Anne; Kelly, Bridget; Chapman, Kathy

2013-12-01

To provide an independent monitoring report examining the ongoing impact of Australian self-regulatory pledges on food and drink advertising to children on commercial television. Analysis of food advertisements across comparable sample time periods in April/May 2006, 2007, 2009, 2010 and 2011. The main outcome measure comprised change in the mean rate of non-core food advertisements from 2006 to 2011. Sydney free-to-air television channels. Televised food advertisements. In 2011 the rate of non-core food advertisements was not significantly different from that in 2006 or 2010 (3·2/h v. 4·1/h and 3·1/h), although there were variations across the intervening years. The rate of fast-food advertising in 2010 was significantly higher than in 2006 (1·8/h v. 1·1/h, P < 0·001), but the same as that in 2011 (1·5/h). The frequency of non-core food advertising on Sydney television has remained essentially unchanged between 2006 and 2011, despite the implementation of two industry self-regulatory pledges. The current study illustrates the value of independent monitoring as a basic requirement of any responsive regulatory approach.

Characterization of shredded television scrap and implications for materials recovery.

PubMed

Cui, Jirang; Forssberg, Eric

2007-01-01

Characterization of TV scrap was carried out by using a variety of methods, such as chemical analysis, particle size and shape analysis, liberation degree analysis, thermogravimetric analysis, sink-float test, and IR spectrometry. A comparison of TV scrap, personal computer scrap, and printed circuit board scrap shows that the content of non-ferrous metals and precious metals in TV scrap is much lower than that in personal computer scrap or printed circuit board scrap. It is expected that recycling of TV scrap will not be cost-effective by utilizing conventional manual disassembly. The result of particle shape analysis indicates that the non-ferrous metal particles in TV scrap formed as a variety of shapes; it is much more heterogeneous than that of plastics and printed circuit boards. Furthermore, the separability of TV scrap using density-based techniques was evaluated by the sink-float test. The result demonstrates that a high recovery of copper could be obtained by using an effective gravity separation process. Identification of plastics shows that the major plastic in TV scrap is high impact polystyrene. Gravity separation of plastics may encounter some challenges in separation of plastics from TV scrap because of specific density variations.

Characterization of optical-surface-imaging-based spirometry for respiratory surrogating in radiotherapy

PubMed Central

Li, Guang; Huang, Hailiang; Chen, Qing; Gaebler, Carl P.; Lin, Tiffany; Yuan, Amy; Rimner, Andreas; Mechalakos, James

2016-01-01

Purpose: To provide a comprehensive characterization of a novel respiratory surrogate that uses optical surface imaging (OSI) for accurate tidal volume (TV) measurement, dynamic airflow (TV′) calculation, and quantitative breathing pattern (BP) estimation during free breathing (FB), belly breathing (BB), chest breathing (CB), and breath hold (BH). Methods: Optical surface imaging, which captures all respiration-induced torso surface motion, was applied to measure respiratory TV, TV′, and BP in three common breathing patterns. Eleven healthy volunteers participated in breathing experiments with concurrent OSI-based and conventional spirometric measurements under an institutional review board approved protocol. This OSI-based technique measures dynamic TV from torso volume change (ΔVtorso = TV) in reference to full exhalation and airflow (TV′ = dTV/dt). Volume conservation, excluding exchanging air, was applied for OSI-based measurements under negligible pleural pressure variation in FB, BB, and CB. To demonstrate volume conservation, a constant TV was measured during BH while the chest and belly are moving (“pretended” respiration). To assess the accuracy of OSI-based spirometry, a conventional spirometer was used as the standard for both TV and TV′. Using OSI, BP was measured as BPOSI = ΔVchest/ΔVtorso and BP can be visualized using BPSHI = SHIchest/(SHIchest + SHIbelly), where surface height index (SHI) is defined as the mean vertical distance within a region of interest on the torso surface. A software tool was developed for OSI image processing, volume calculation, and BP visualization, and another tool was implemented for data acquisition using a Bernoulli-type spirometer. Results: The accuracy of the OSI-based spirometry is −21 ± 33 cm3 or −3.5% ± 6.3% averaged from 11 volunteers with 76 ± 28 breathing cycles on average in FB. Breathing variations between two separate acquisitions with approximate 30-min intervals are substantial: −1% ± 34% (ranging from −64% to 40%) in TV, 4% ± 20% (ranging from −50% to 26%) in breathing period (T), and −1% ± 34% (ranging from −49% to 44%) in BP. The airflow accuracy and variation (between two exercises) are −1 ± 54 cm3/s and −5% ± 30%, respectively. The slope of linear regression between OSI–TV and spirometric TV is 0.93 (R2 = 0.95) for FB, 0.96 (R2 = 0.98) for BB, and 0.95 (R2 = 0.95) for CB. The correlation between the two spirometric measurements is 0.98 ± 0.01. BP increases from BB, FB to CB, while TV increases from FB, BB, to CB. Under BH, 4% volume variation (range) on average was observed. Conclusions: The OSI-based technique provides an accurate measurement of tidal volume, airflow rate, and breathing pattern; all affect internal organ motion. This technique can be applied to various breathing patterns, including FB, BB, and CB. Substantial breathing irregularities and irreproducibility were observed and quantified with the OSI-based technique. These breathing parameters are useful to quantify breathing conditions, which could be used for effective tumor motion predictions. PMID:26936719

Adoption and Use of Videocassette Recorders in the Third World.

ERIC Educational Resources Information Center

Straubhaar, Joseph; Boyd, Douglas A.

Videocassette recorder (VCR) acquisition and use in developing nations is largely an individual or household decision, and their rapid diffusion is influenced by several factors: price, and its variations due to government restrictions; income and income distribution; the content of broadcast television; the diversity of entertainment media…

Toward a qualitative understanding of binge-watching behaviors: A focus group approach.

PubMed

Flayelle, Maèva; Maurage, Pierre; Billieux, Joël

2017-12-01

Background and aims Binge-watching (i.e., seeing multiple episodes of the same TV series in a row) now constitutes a widespread phenomenon. However, little is known about the psychological factors underlying this behavior, as reflected by the paucity of available studies, most merely focusing on its potential harmfulness by applying the classic criteria used for other addictive disorders without exploring the uniqueness of binge-watching. This study thus aimed to take the opposite approach as a first step toward a genuine understanding of binge-watching behaviors through a qualitative analysis of the phenomenological characteristics of TV series watching. Methods A focus group of regular TV series viewers (N = 7) was established to explore a wide range of aspects related to TV series watching (e.g., motives, viewing practices, and related behaviors). Results A content analysis identified binge-watching features across three dimensions: TV series watching motivations, TV series watching engagement, and structural characteristics of TV shows. Most participants acknowledged that TV series watching can become addictive, but they all agreed having trouble recognizing themselves as truly being an "addict." Although obvious connections could be established with substance addiction criteria and symptoms, such parallelism appeared to be insufficient, as several distinctive facets emerged (e.g., positive view, transient overinvolvement, context dependency, and low everyday life impact). Discussion and conclusion The research should go beyond the classic biomedical and psychological models of addictive behaviors to account for binge-watching in order to explore its specificities and generate the first steps toward an adequate theoretical rationale for these emerging problematic behaviors.

A limited-angle CT reconstruction method based on anisotropic TV minimization.

PubMed

Chen, Zhiqiang; Jin, Xin; Li, Liang; Wang, Ge

2013-04-07

This paper presents a compressed sensing (CS)-inspired reconstruction method for limited-angle computed tomography (CT). Currently, CS-inspired CT reconstructions are often performed by minimizing the total variation (TV) of a CT image subject to data consistency. A key to obtaining high image quality is to optimize the balance between TV-based smoothing and data fidelity. In the case of the limited-angle CT problem, the strength of data consistency is angularly varying. For example, given a parallel beam of x-rays, information extracted in the Fourier domain is mostly orthogonal to the direction of x-rays, while little is probed otherwise. However, the TV minimization process is isotropic, suggesting that it is unfit for limited-angle CT. Here we introduce an anisotropic TV minimization method to address this challenge. The advantage of our approach is demonstrated in numerical simulation with both phantom and real CT images, relative to the TV-based reconstruction.

Novel crystal timing calibration method based on total variation

NASA Astrophysics Data System (ADS)

Yu, Xingjian; Isobe, Takashi; Watanabe, Mitsuo; Liu, Huafeng

2016-11-01

A novel crystal timing calibration method based on total variation (TV), abbreviated as ‘TV merge’, has been developed for a high-resolution positron emission tomography (PET) system. The proposed method was developed for a system with a large number of crystals, it can provide timing calibration at the crystal level. In the proposed method, the timing calibration process was formulated as a linear problem. To robustly optimize the timing resolution, a TV constraint was added to the linear equation. Moreover, to solve the computer memory problem associated with the calculation of the timing calibration factors for systems with a large number of crystals, the merge component was used for obtaining the crystal level timing calibration values. Compared with other conventional methods, the data measured from a standard cylindrical phantom filled with a radioisotope solution was sufficient for performing a high-precision crystal-level timing calibration. In this paper, both simulation and experimental studies were performed to demonstrate the effectiveness and robustness of the TV merge method. We compare the timing resolutions of a 22Na point source, which was located in the field of view (FOV) of the brain PET system, with various calibration techniques. After implementing the TV merge method, the timing resolution improved from 3.34 ns at full width at half maximum (FWHM) to 2.31 ns FWHM.

Food advertising during children's television programming on broadcast and cable channels.

PubMed

Stitt, Carmen; Kunkel, Dale

2008-11-01

The rise in the number of overweight and obese children in the United States is recognized as a serious health threat. Among the factors contributing to this increase is the preponderance of food marketing on television targeted at children. Previous content analysis studies have identified patterns of food product types that are commonly associated with unhealthy diets, but few have attempted to independently evaluate the nutritional quality of advertised foods. This study identifies the nature and extent of food marketing messages presented during children's television programs, while also classifying the products advertised using a U.S. Department of Health and Human Services consumer food rating scheme. The findings indicate that food advertising accounts for nearly half of all commercial messages on children's programs. An average hour includes 11 food ads that account for 4:25 of total ad time. Broadcast channels deliver more food advertising than cable channels, although the types of food products marketed on both channels are highly similar. The overwhelming majority of foods ads directed to children are for high-calorie, low nutrient food products that should not be part of a regular diet. These data provide a baseline for evaluating anticipated future industry efforts at reform, such as attempts to comply with a recent Institute of Medicine (2006) policy recommendation that food marketing to children should be balanced between more healthy and less healthy food products within two years time.

A photoacoustic imaging reconstruction method based on directional total variation with adaptive directivity.

PubMed

Wang, Jin; Zhang, Chen; Wang, Yuanyuan

2017-05-30

In photoacoustic tomography (PAT), total variation (TV) based iteration algorithm is reported to have a good performance in PAT image reconstruction. However, classical TV based algorithm fails to preserve the edges and texture details of the image because it is not sensitive to the direction of the image. Therefore, it is of great significance to develop a new PAT reconstruction algorithm to effectively solve the drawback of TV. In this paper, a directional total variation with adaptive directivity (DDTV) model-based PAT image reconstruction algorithm, which weightedly sums the image gradients based on the spatially varying directivity pattern of the image is proposed to overcome the shortcomings of TV. The orientation field of the image is adaptively estimated through a gradient-based approach. The image gradients are weighted at every pixel based on both its anisotropic direction and another parameter, which evaluates the estimated orientation field reliability. An efficient algorithm is derived to solve the iteration problem associated with DDTV and possessing directivity of the image adaptively updated for each iteration step. Several texture images with various directivity patterns are chosen as the phantoms for the numerical simulations. The 180-, 90- and 30-view circular scans are conducted. Results obtained show that the DDTV-based PAT reconstructed algorithm outperforms the filtered back-projection method (FBP) and TV algorithms in the quality of reconstructed images with the peak signal-to-noise rations (PSNR) exceeding those of TV and FBP by about 10 and 18 dB, respectively, for all cases. The Shepp-Logan phantom is studied with further discussion of multimode scanning, convergence speed, robustness and universality aspects. In-vitro experiments are performed for both the sparse-view circular scanning and linear scanning. The results further prove the effectiveness of the DDTV, which shows better results than that of the TV with sharper image edges and clearer texture details. Both numerical simulation and in vitro experiments confirm that the DDTV provides a significant quality improvement of PAT reconstructed images for various directivity patterns.

Trends in US newspaper and television coverage of tobacco.

PubMed

Nelson, David E; Pederson, Linda L; Mowery, Paul; Bailey, Sarah; Sevilimedu, Varadan; London, Joel; Babb, Stephen; Pechacek, Terry

2015-01-01

The news media plays an important role in agenda setting and framing of stories about tobacco control. The purpose of this study was to examine newspaper, newswire and television coverage of tobacco issues in the USA over a 7-year period. Analyses of 2004-2010 news media surveillance system data from the US Centers for Disease Control and Prevention's Office on Smoking and Health, based on content analysis and quantitative methods. Information on extent of news coverage, and types of tobacco-related themes, were examined from articles in 10 newspapers and 2 major newswires, as well as transcripts from 6 national television networks. The overall extent of newspaper, newswire and television stories about tobacco, and level of coverage by specific media outlets, varied over time, especially for newspapers. Nevertheless, there was an average of 3 newspaper stories, 4 newswire stories, and 1 television tobacco-related story each day. Television stories were more likely to contain cessation/addiction or health effects/statistics themes and less likely to contain secondhand smoke or policy/regulation themes than newspaper/newswire stories. There was more variation in the choice of tobacco theme among individual newspapers/newswires than television media outlets. News coverage of tobacco in the USA was relatively constant from 2004 to 2010. Audiences were more likely to be exposed to different tobacco themes in newspapers/newswires than on television. Tracking information about tobacco news stories can be used by advocates, programs and others for planning and evaluation, and by researchers for hypothesis generation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Low dose CT reconstruction via L1 norm dictionary learning using alternating minimization algorithm and balancing principle.

PubMed

Wu, Junfeng; Dai, Fang; Hu, Gang; Mou, Xuanqin

2018-04-18

Excessive radiation exposure in computed tomography (CT) scans increases the chance of developing cancer and has become a major clinical concern. Recently, statistical iterative reconstruction (SIR) with l0-norm dictionary learning regularization has been developed to reconstruct CT images from the low dose and few-view dataset in order to reduce radiation dose. Nonetheless, the sparse regularization term adopted in this approach is l0-norm, which cannot guarantee the global convergence of the proposed algorithm. To address this problem, in this study we introduced the l1-norm dictionary learning penalty into SIR framework for low dose CT image reconstruction, and developed an alternating minimization algorithm to minimize the associated objective function, which transforms CT image reconstruction problem into a sparse coding subproblem and an image updating subproblem. During the image updating process, an efficient model function approach based on balancing principle is applied to choose the regularization parameters. The proposed alternating minimization algorithm was evaluated first using real projection data of a sheep lung CT perfusion and then using numerical simulation based on sheep lung CT image and chest image. Both visual assessment and quantitative comparison using terms of root mean square error (RMSE) and structural similarity (SSIM) index demonstrated that the new image reconstruction algorithm yielded similar performance with l0-norm dictionary learning penalty and outperformed the conventional filtered backprojection (FBP) and total variation (TV) minimization algorithms.

Sparse magnetic resonance imaging reconstruction using the bregman iteration

NASA Astrophysics Data System (ADS)

Lee, Dong-Hoon; Hong, Cheol-Pyo; Lee, Man-Woo

2013-01-01

Magnetic resonance imaging (MRI) reconstruction needs many samples that are sequentially sampled by using phase encoding gradients in a MRI system. It is directly connected to the scan time for the MRI system and takes a long time. Therefore, many researchers have studied ways to reduce the scan time, especially, compressed sensing (CS), which is used for sparse images and reconstruction for fewer sampling datasets when the k-space is not fully sampled. Recently, an iterative technique based on the bregman method was developed for denoising. The bregman iteration method improves on total variation (TV) regularization by gradually recovering the fine-scale structures that are usually lost in TV regularization. In this study, we studied sparse sampling image reconstruction using the bregman iteration for a low-field MRI system to improve its temporal resolution and to validate its usefulness. The image was obtained with a 0.32 T MRI scanner (Magfinder II, SCIMEDIX, Korea) with a phantom and an in-vivo human brain in a head coil. We applied random k-space sampling, and we determined the sampling ratios by using half the fully sampled k-space. The bregman iteration was used to generate the final images based on the reduced data. We also calculated the root-mean-square-error (RMSE) values from error images that were obtained using various numbers of bregman iterations. Our reconstructed images using the bregman iteration for sparse sampling images showed good results compared with the original images. Moreover, the RMSE values showed that the sparse reconstructed phantom and the human images converged to the original images. We confirmed the feasibility of sparse sampling image reconstruction methods using the bregman iteration with a low-field MRI system and obtained good results. Although our results used half the sampling ratio, this method will be helpful in increasing the temporal resolution at low-field MRI systems.

WE-G-207-04: Non-Local Total-Variation (NLTV) Combined with Reweighted L1-Norm for Compressed Sensing Based CT Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, H; Chen, J; Pouliot, J

2015-06-15

Purpose: Compressed sensing (CS) has been used for CT (4DCT/CBCT) reconstruction with few projections to reduce dose of radiation. Total-variation (TV) in L1-minimization (min.) with local information is the prevalent technique in CS, while it can be prone to noise. To address the problem, this work proposes to apply a new image processing technique, called non-local TV (NLTV), to CS based CT reconstruction, and incorporate reweighted L1-norm into it for more precise reconstruction. Methods: TV minimizes intensity variations by considering two local neighboring voxels, which can be prone to noise, possibly damaging the reconstructed CT image. NLTV, contrarily, utilizes moremore » global information by computing a weight function of current voxel relative to surrounding search area. In fact, it might be challenging to obtain an optimal solution due to difficulty in defining the weight function with appropriate parameters. Introducing reweighted L1-min., designed for approximation to ideal L0-min., can reduce the dependence on defining the weight function, therefore improving accuracy of the solution. This work implemented the NLTV combined with reweighted L1-min. by Split Bregman Iterative method. For evaluation, a noisy digital phantom and a pelvic CT images are employed to compare the quality of images reconstructed by TV, NLTV and reweighted NLTV. Results: In both cases, conventional and reweighted NLTV outperform TV min. in signal-to-noise ratio (SNR) and root-mean squared errors of the reconstructed images. Relative to conventional NLTV, NLTV with reweighted L1-norm was able to slightly improve SNR, while greatly increasing the contrast between tissues due to additional iterative reweighting process. Conclusion: NLTV min. can provide more precise compressed sensing based CT image reconstruction by incorporating the reweighted L1-norm, while maintaining greater robustness to the noise effect than TV min.« less

An adaptive DPCM algorithm for predicting contours in NTSC composite video signals

NASA Astrophysics Data System (ADS)

Cox, N. R.

An adaptive DPCM algorithm is proposed for encoding digitized National Television Systems Committee (NTSC) color video signals. This algorithm essentially predicts picture contours in the composite signal without resorting to component separation. The contour parameters (slope thresholds) are optimized using four 'typical' television frames that have been sampled at three times the color subcarrier frequency. Three variations of the basic predictor are simulated and compared quantitatively with three non-adaptive predictors of similar complexity. By incorporating a dual-word-length coder and buffer memory, high quality color pictures can be encoded at 4.0 bits/pel or 42.95 Mbit/s. The effect of channel error propagation is also investigated.

TVs in the bedrooms of children: does it impact health and behavior?

PubMed

Sisson, Susan B; Broyles, Stephanie T; Newton, Robert L; Baker, Birgitta L; Chernausek, Steven D

2011-02-01

To (1) determine socio-demographic characteristics associated with a TV in the bedroom (BTV) and (2) examine relationship of BTV, independent of total viewing time, with social and behavioral characteristics. Children 6-17 years from the 2007 US National Survey of Children's Health were included (n=48,687). BTV, daily TV viewing time, demographic, behavioral and social outcomes (community involvement, social skills, health habits and status, and family) were examined using logistic regression, and adjusted for total viewing time. Overall prevalence of BTV was 49.3% in American children. Older age, non-Hispanic Black (71.3%), Hispanics (56.3%), higher level of poverty (>56.2%), non two-parent biological family structure (>62.6%), Midwest (47.1%), Northeast (46.7%), South Atlantic (56.4%) and South Central (59.8%) region of the country were associated with higher odds of BTV. Female gender (52.7%) and residence in Alaska (33.0%) were associated with lower prevalence of BTV. BTV was associated with higher prevalence of exhibiting problematic social behaviors (29%) and overweight status (44%). BTV was significantly associated with lower prevalence of regular family meals (13%), engagement in school (16%), participation in extracurricular activities (31%), regularly sleeping enough (20%), and participation in community service (25%) after adjustment for total viewing time. BTV appears associated with more social and behavioral indices than previously reported, in addition to total viewing time. Copyright © 2010 Elsevier Inc. All rights reserved.

47 CFR 74.1203 - Interference.

Code of Federal Regulations, 2014 CFR

2014-10-01

... FM Broadcast Booster Stations § 74.1203 Interference. (a) An authorized FM translator or booster..., TV booster, FM translator or FM booster station; or (3) The direct reception by the public of the off... FM booster stations. Interference will be considered to occur whenever reception of a regularly used...

47 CFR 74.1203 - Interference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... FM Broadcast Booster Stations § 74.1203 Interference. (a) An authorized FM translator or booster..., TV booster, FM translator or FM booster station; or (3) The direct reception by the public of the off... FM booster stations. Interference will be considered to occur whenever reception of a regularly used...

47 CFR 74.1203 - Interference.

Code of Federal Regulations, 2011 CFR

2011-10-01

... FM Broadcast Booster Stations § 74.1203 Interference. (a) An authorized FM translator or booster..., TV booster, FM translator or FM booster station; or (3) The direct reception by the public of the off... FM booster stations. Interference will be considered to occur whenever reception of a regularly used...

47 CFR 74.1203 - Interference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... FM Broadcast Booster Stations § 74.1203 Interference. (a) An authorized FM translator or booster..., TV booster, FM translator or FM booster station; or (3) The direct reception by the public of the off... FM booster stations. Interference will be considered to occur whenever reception of a regularly used...

Family structure as a predictor of screen time among youth.

PubMed

McMillan, Rachel; McIsaac, Michael; Janssen, Ian

2015-01-01

The family plays a central role in the development of health-related behaviors among youth. The objective of this study was to determine whether non-traditional parental structure and shared custody arrangements predict how much time youth spend watching television, using a computer recreationally, and playing video games. Participants were a nationally representative sample of Canadian youth (N = 26,068) in grades 6-10 who participated in the 2009/10 Health Behaviour in School-aged Children Survey. Screen time in youth from single parent and reconstituted families, with or without regular visitation with their non-residential parent, was compared to that of youth from traditional dual-parent families. Multiple imputation was used to account for missing data. After multiple imputation, the relative odds of being in the highest television, computer use, video game, and total screen time quartiles were not different in boys and girls from non-traditional families by comparison to boys and girls from traditional dual-parent families. In conclusion, parental structure and child custody arrangements did not have a meaningful impact on screen time among youth.

Looking for boomerang effects: a pre-post experimental study of the effects of exposure of youth to television advertising for nicotine replacement therapy and Zyban.

PubMed

Durkin, Sarah; Wakefield, Melanie; Spittal, Matt

2006-12-01

In the context of concerns about unintended "boomerang" influences of advertising, this study aimed to examine effects of nicotine replacement therapy (NRT) and Zyban advertising on youth perceptions of the ease of quitting, health risks of smoking and future intentions to smoke. 718 youth aged 14-16years were randomly allocated to view four television ads promoting either: NRT; Zyban; non-pharmaceutical cessation services (telephone Quitline); or non-cessation messages on sun protection. Questionnaire measures were administered before and after viewing ads. There were no effects of advertising exposure on perceived health effects of smoking or intentions to smoke. Compared with the sun protection ads, but not the Quitline ads, those exposed to NRT ads reported stronger perceptions about the ease of quitting, but non-susceptible non-smokers primarily drove this difference. This study suggests that exposure to NRT and Zyban advertising in an experimental context does not reliably influence youth smoking-related beliefs, especially those vulnerable to becoming regular smokers.

[Media use with developmental benefits].

PubMed

Hipeli, E; Süss, D

2012-08-01

For children of school age television is still the dominant medium. TV consumption isn't only limited on the TV set, but also happens on the computer with internet access and mobile devices. Computer games take a high priority for boys. For girls reading is still an important experience space. Parents influence the media use of their children by their role model, and the rates for shared non-media experiences. Neighborhoods which aren't child-friendly can cause children's withdraw into home media spaces. Restrictions and controls are less important than the conversations that are conducted around media interests of the child and parents attention to early signs of problematic media use. Potentially irritating media content for children (such as violence or sex) can have strong effects when there's no open debate taking place in the family around these issues. Today's media diversity leads to parallel surfing and multi-tasking. In order that this doesn't influence children's cognitive development and learning negatively a culture of regular restriction to one activity, to which they devote their full attention, is required.

The extent and nature of alcohol advertising on Australian television.

PubMed

Pettigrew, Simone; Roberts, Michele; Pescud, Melanie; Chapman, Kathy; Quester, Pascale; Miller, Caroline

2012-09-01

Current alcohol guidelines in Australia recommend minimising alcohol consumption, especially among minors. This study investigated (i) the extent to which children and the general population are exposed to television advertisements that endorse alcohol consumption and (ii) the themes used in these advertisements. A content analysis was conducted on alcohol advertisements aired over two months in major Australian cities. The advertisements were coded according to the products that were promoted, the themes that were employed, and the time of exposure. Advertising placement expenditure was also captured. In total, 2810 alcohol advertisements were aired, representing one in 10 beverage advertisements. Advertisement placement expenditure for alcohol products in the five cities over the two months was $15.8 million. Around half of all alcohol advertisements appeared during children's popular viewing times. The most common themes used were humour, friendship/mateship and value for money. Children and adults are regularly exposed to advertisements that depict alcohol consumption as fun, social and inexpensive. Such messages may reinforce existing alcohol-related cultural norms that prevent many Australians from meeting current intake guidelines. © 2012 Australasian Professional Society on Alcohol and other Drugs.

Sexy media matter: exposure to sexual content in music, movies, television, and magazines predicts black and white adolescents' sexual behavior.

PubMed

Brown, Jane D; L'Engle, Kelly Ladin; Pardun, Carol J; Guo, Guang; Kenneavy, Kristin; Jackson, Christine

2006-04-01

To assess over time whether exposure to sexual content in 4 mass media (television, movies, music, and magazines) used by early adolescents predicts sexual behavior in middle adolescence. An in-home longitudinal survey of 1017 black and white adolescents from 14 middle schools in central North Carolina was conducted. Each teen was interviewed at baseline when he or she was 12 to 14 years old and again 2 years later using a computer-assisted self interview (audio computer-assisted self-interview) to ensure confidentiality. A new measure of each teen's sexual media diet (SMD) was constructed by weighting the frequency of use of 4 media by the frequency of sexual content in each television show, movie, music album, and magazine the teen used regularly. White adolescents in the top quintile of sexual media diet when 12 to 14 years old were 2.2 times more likely to have had sexual intercourse when 14 to 16 years old than those who were in the lowest SMD quintile, even after a number of other relevant factors, including baseline sexual behavior, were introduced. The relationship was not statistically significant for black adolescents after controlling for other factors that were more predictive, including parental disapproval of teen sex and perceived permissive peer sexual norms. Exposure to sexual content in music, movies, television, and magazines accelerates white adolescents' sexual activity and increases their risk of engaging in early sexual intercourse. Black teens appear more influenced by perceptions of their parents' expectations and their friends' sexual behavior than by what they see and hear in the media.

Low-mAs X-ray CT image reconstruction by adaptive-weighted TV-constrained penalized re-weighted least-squares

PubMed Central

Liu, Yan; Ma, Jianhua; Zhang, Hao; Wang, Jing; Liang, Zhengrong

2014-01-01

Background The negative effects of X-ray exposure, such as inducing genetic and cancerous diseases, has arisen more attentions. Objective This paper aims to investigate a penalized re-weighted least-square (PRWLS) strategy for low-mAs X-ray computed tomography image reconstruction by incorporating an adaptive weighted total variation (AwTV) penalty term and a noise variance model of projection data. Methods An AwTV penalty is introduced in the objective function by considering both piecewise constant property and local nearby intensity similarity of the desired image. Furthermore, the weight of data fidelity term in the objective function is determined by our recent study on modeling variance estimation of projection data in the presence of electronic background noise. Results The presented AwTV-PRWLS algorithm can achieve the highest full-width-at-half-maximum (FWHM) measurement, for data conditions of (1) full-view 10mA acquisition and (2) sparse-view 80mA acquisition. In comparison between the AwTV/TV-PRWLS strategies and the previous reported AwTV/TV-projection onto convex sets (AwTV/TV-POCS) approaches, the former can gain in terms of FWHM for data condition (1), but cannot gain for the data condition (2). Conclusions In the case of full-view 10mA projection data, the presented AwTV-PRWLS shows potential improvement. However, in the case of sparse-view 80mA projection data, the AwTV/TV-POCS shows advantage over the PRWLS strategies. PMID:25080113

Preliminary comparison of continuous versus noncontinuous programming and attitude toward and recall of advertisements.

PubMed

Akyamaç, Orkide; Oner-Ozkan, Bengi

2006-04-01

Need for continuity of a television program was assessed with attitude toward and recall of advertisements. The program continuity was manipulated experimentally by presenting one music video program as Top 10 (continuous) or as Regular (discontinuous) format. General attitude toward commercials and the belief in advertisement-product realism were investigated through the commercials with continuous and discontinuous formats of the same program. Data were gathered from undergraduates (23 men and 68 women) whose mean age was 20.2 yr. (SD=2.5). Analyses indicated continuity was not related to their attitude towards embedded commercials but was associated with their recall. Implications were discussed.

Associations of television viewing time with adults' well-being and vitality.

PubMed

Dempsey, Paddy C; Howard, Bethany J; Lynch, Brigid M; Owen, Neville; Dunstan, David W

2014-12-01

Television (TV) viewing, a common leisure-time sedentary behaviour, is associated adversely with cardio-metabolic health, fatigue, depression and mental health. However, associations of TV viewing time with health-related quality of life attributes are less well understood. We examined associations of TV viewing time with physical well-being, mental well-being and vitality in a large population-based sample of Australian adults. The study sample comprised 4,483 men and 5,424 women (mean age 51±14years) from the Australian Diabetes, Obesity and Lifestyle study (1999-2000). Multiple linear regressions examined associations of TV viewing time (h/day) with the SF-36v1 physical and mental health component summary scores and the vitality sub-score, adjusting for leisure-time physical activity and waist circumference. Each 1-h/day increment in TV viewing time was associated with lower physical (-0.56 [95% CI: -0.77, -0.34]) and mental (-0.41 [-0.70, -0.12]) component summary scores and vitality (-0.51 [-0.81, -0.21]). Associations remained significant after adjustment for leisure-time physical activity and waist circumference. There was a gender interaction for the association of TV viewing time with vitality (significant in men only). TV viewing time is associated adversely with physical well-being, mental well-being and vitality. Further studies are required to better understand potential causal relationships and variations by gender and leisure-time physical activity. Copyright © 2014 Elsevier Inc. All rights reserved.

The remote, the mouse, and the no. 2 pencil: the household media environment and academic achievement among third grade students.

PubMed

Borzekowski, Dina L G; Robinson, Thomas N

2005-07-01

Media can influence aspects of a child's physical, social, and cognitive development; however, the associations between a child's household media environment, media use, and academic achievement have yet to be determined. To examine relationships among a child's household media environment, media use, and academic achievement. During a single academic year, data were collected through classroom surveys and telephone interviews from an ethnically diverse sample of third grade students and their parents from 6 northern California public elementary schools. The majority of our analyses derive from spring 2000 data, including academic achievement assessed through the mathematics, reading, and language arts sections of the Stanford Achievement Test. We fit linear regression models to determine the associations between variations in household media and performance on the standardized tests, adjusting for demographic and media use variables. The household media environment is significantly associated with students' performance on the standardized tests. It was found that having a bedroom television set was significantly and negatively associated with students' test scores, while home computer access and use were positively associated with the scores. Regression models significantly predicted up to 24% of the variation in the scores. Absence of a bedroom television combined with access to a home computer was consistently associated with the highest standardized test scores. This study adds to the growing literature reporting that having a bedroom television set may be detrimental to young elementary school children. It also suggests that having and using a home computer may be associated with better academic achievement.

Body-Image Evaluation and Body-Image Investment among Adolescents: A Test of Sociocultural and Social Comparison Theories

ERIC Educational Resources Information Center

Morrison, Todd G.; Kalin, Rudolf; Morrison, Melanie A.

2004-01-01

Sociocultural theory and social comparison theory were used to account for variations in body-image evaluation and body-image investment among male and female adolescents (N = 1,543). Exposure to magazines and television programs containing idealistic body imagery as well as frequency of self-comparison to universalistic targets (e.g., fashion…

Research on compressive sensing reconstruction algorithm based on total variation model

NASA Astrophysics Data System (ADS)

Gao, Yu-xuan; Sun, Huayan; Zhang, Tinghua; Du, Lin

2017-12-01

Compressed sensing for breakthrough Nyquist sampling theorem provides a strong theoretical , making compressive sampling for image signals be carried out simultaneously. In traditional imaging procedures using compressed sensing theory, not only can it reduces the storage space, but also can reduce the demand for detector resolution greatly. Using the sparsity of image signal, by solving the mathematical model of inverse reconfiguration, realize the super-resolution imaging. Reconstruction algorithm is the most critical part of compression perception, to a large extent determine the accuracy of the reconstruction of the image.The reconstruction algorithm based on the total variation (TV) model is more suitable for the compression reconstruction of the two-dimensional image, and the better edge information can be obtained. In order to verify the performance of the algorithm, Simulation Analysis the reconstruction result in different coding mode of the reconstruction algorithm based on the TV reconstruction algorithm. The reconstruction effect of the reconfigurable algorithm based on TV based on the different coding methods is analyzed to verify the stability of the algorithm. This paper compares and analyzes the typical reconstruction algorithm in the same coding mode. On the basis of the minimum total variation algorithm, the Augmented Lagrangian function term is added and the optimal value is solved by the alternating direction method.Experimental results show that the reconstruction algorithm is compared with the traditional classical algorithm based on TV has great advantages, under the low measurement rate can be quickly and accurately recovers target image.

MO-DE-207A-02: A Feature-Preserving Image Reconstruction Method for Improved Pancreaticlesion Classification in Diagnostic CT Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, J; Tsui, B; Noo, F

Purpose: To develop a feature-preserving model based image reconstruction (MBIR) method that improves performance in pancreatic lesion classification at equal or reduced radiation dose. Methods: A set of pancreatic lesion models was created with both benign and premalignant lesion types. These two classes of lesions are distinguished by their fine internal structures; their delineation is therefore crucial to the task of pancreatic lesion classification. To reduce image noise while preserving the features of the lesions, we developed a MBIR method with curvature-based regularization. The novel regularization encourages formation of smooth surfaces that model both the exterior shape and the internalmore » features of pancreatic lesions. Given that the curvature depends on the unknown image, image reconstruction or denoising becomes a non-convex optimization problem; to address this issue an iterative-reweighting scheme was used to calculate and update the curvature using the image from the previous iteration. Evaluation was carried out with insertion of the lesion models into the pancreas of a patient CT image. Results: Visual inspection was used to compare conventional TV regularization with our curvature-based regularization. Several penalty-strengths were considered for TV regularization, all of which resulted in erasing portions of the septation (thin partition) in a premalignant lesion. At matched noise variance (50% noise reduction in the patient stomach region), the connectivity of the septation was well preserved using the proposed curvature-based method. Conclusion: The curvature-based regularization is able to reduce image noise while simultaneously preserving the lesion features. This method could potentially improve task performance for pancreatic lesion classification at equal or reduced radiation dose. The result is of high significance for longitudinal surveillance studies of patients with pancreatic cysts, which may develop into pancreatic cancer. The Senior Author receives financial support from Siemens GmbH Healthcare.« less

A systematic method for using 3D echocardiography to evaluate tricuspid valve insufficiency in hypoplastic left heart syndrome.

PubMed

Mart, Christopher Robin; Eckhauser, Aaron Wesley; Murri, Michael; Su, Jason Thomas

2014-09-01

With surgical palliation of hypoplastic left heart syndrome (HLHS), the tricuspid valve (TV) becomes the systemic atrioventricular valve and moderate/severe TV insufficiency (TVI), an adverse risk factor for survival to Fontan, has been reported in up to 35% of patients prior to stage I palliation. Precise echocardiographic identification of the mechanism of TVI cannot be determined by two-dimensional echocardiography. Three-dimensional echocardiography (3DE) can provide significant insight into the mechanisms of TVI. It is the intent of this report to propose a systematic method on how to evaluate and display 3DE images of the TV in HLHS which has not been done previously. TV anatomy, function, and the known mechanisms of insufficiency are reviewed. We defined three regions of the TV (anterior, posterior, septal) that can help define valve "leaflets" that incorporates the many variations of TV anatomy. To determine how the surgeon views the TV, a picture of a pathologic specimen of the TV was placed on a computer screen and rotated until it was oriented as it appears during surgery, the "surgeons view." We have proposed a systematic method for evaluating and displaying the TV using 3DE which can provide significant insight into the mechanisms causing TVI in HLHS. This has the potential to improve both the surgical approach to repairing the valve and, ultimately, patient outcomes.

A systematic method for using 3D echocardiography to evaluate tricuspid valve insufficiency in hypoplastic left heart syndrome

PubMed Central

Mart, Christopher Robin; Eckhauser, Aaron Wesley; Murri, Michael; Su, Jason Thomas

2014-01-01

With surgical palliation of hypoplastic left heart syndrome (HLHS), the tricuspid valve (TV) becomes the systemic atrioventricular valve and moderate/severe TV insufficiency (TVI), an adverse risk factor for survival to Fontan, has been reported in up to 35% of patients prior to stage I palliation. Precise echocardiographic identification of the mechanism of TVI cannot be determined by two-dimensional echocardiography. Three-dimensional echocardiography (3DE) can provide significant insight into the mechanisms of TVI. It is the intent of this report to propose a systematic method on how to evaluate and display 3DE images of the TV in HLHS which has not been done previously. TV anatomy, function, and the known mechanisms of insufficiency are reviewed. We defined three regions of the TV (anterior, posterior, septal) that can help define valve “leaflets” that incorporates the many variations of TV anatomy. To determine how the surgeon views the TV, a picture of a pathologic specimen of the TV was placed on a computer screen and rotated until it was oriented as it appears during surgery, the “surgeons view.” We have proposed a systematic method for evaluating and displaying the TV using 3DE which can provide significant insight into the mechanisms causing TVI in HLHS. This has the potential to improve both the surgical approach to repairing the valve and, ultimately, patient outcomes. PMID:25298694

Morphological Variations in the Transverse Venous Sinus Anatomy of Dogs and its Relationship to Skull Landmarks.

PubMed

Carreira, L Miguel; Ferreira, A

2016-08-01

We characterized the anatomical morphology of the transverse venous sinus (TVS) of 69 canine adult cadavers belonging to three groups: brachycephalic (B), dolichocephalic (D) and mesaticephalic (M). In addition, we outlined its path over the skull using five classic human craniometric points (CPs): the asterion (ast), the bregma (b), the glabella (g), the stephanion (st) and the pterion (pt). The study aimed to establish anatomical differences in the TVS between groups and in the relationship between the TVS and skull. We found that TVS anatomy and its relationships to skull landmarks vary markedly between the groups, with similar anatomical arrangements in B and M. The TVS length can be ranked as M < B < D (with D being the biggest), whereas the width can be ranked as M < D < B (with B being the widest) with the right side being smaller than the left. In the B and M groups, the TVS assumes a craniocaudal trajectory that is closer to the lateral skull wall than in D, where the TVS presents a caudocranial direction. By documenting the morphological characteristics of the TVS, we can create a set of anatomical references allowing construction of a basic framework to greatly decrease the probability of TVS injury during neuronavigation procedures when supported by a good knowledge of the skull, brain anatomies and their relationships. © 2015 Blackwell Verlag GmbH.

A content analysis of children's television advertising: focus on food and oral health.

PubMed

Morgan, Maria; Fairchild, Ruth; Phillips, Andrea; Stewart, Kate; Hunter, Lindsay

2009-06-01

To analyse the nature and content of advertising during children's popular television viewing times with the specific aims of (i) identifying the proportion of advertising time devoted to confectionery and potentially cariogenic products (those which readily give rise to dental caries, more commonly known as tooth decay); and (ii) determining whether there is a variation in the advertisement of confectionery and other high-sugar products within children's school holiday time v. outside holiday time.MethodIn five separate one-week periods, the output of the four most popular British children's commercial television channels was video-recorded during the most popular viewing times for children. In total, 503 h of television were recorded and analysed. Analysis of the recordings revealed that 16.4 % of advertising time was devoted to food products; 6.3 % of all advertising time was devoted to potentially cariogenic products. Sugared cereals were the most commonly advertised high-sugar product, followed by sweetened dairy products and confectionery (chi2 = 6524.8, df = 4, P < 0.001). The advertisement of confectionery and high-sugar foods appeared to be influenced by school holidays. Health-care professionals should be aware of the shift away from the advertisement of confectionery towards the promotion of foods that might be considered healthier but contain large amounts of hidden sugar.

Use of a personal computer for dynamical engineering illustrations in a classroom and over an instructional TV network

NASA Technical Reports Server (NTRS)

Watson, V. R.

1983-01-01

A personal computer has been used to illustrate physical phenomena and problem solution techniques in engineering classes. According to student evaluations, instruction of concepts was greatly improved through the use of these illustrations. This paper describes the class of phenomena that can be effectively illustrated, the techniques used to create these illustrations, and the techniques used to display the illustrations in regular classrooms and over an instructional TV network. The features of a personal computer required to apply these techniques are listed. The capabilities of some present personal computers are discussed and a forecast of the capabilities of future personal computers is presented.

Mass Communication: Abstracts of Doctoral Dissertations Published in "Dissertation Abstracts International," January through June 1981 (Vol. 41 Nos. 7 through 12).

ERIC Educational Resources Information Center

ERIC Clearinghouse on Reading and Communication Skills, Urbana, IL.

This collection of abstracts is part of a continuing series providing information on recent doctoral dissertations. The 47 titles deal with a variety of topics, including the following: (1) the effect of source variation upon children's reactions to television commercials; (2) covert observation as a means of measuring the affective states of…

Battle for Ulster. A Study of Internal Security

DTIC Science & Technology

1987-06-01

More than twenty-three nations sent television crews, with American networks alone assigning sixteen. Over 400 journalists -were present. It=was, for...Independence. Another settlement option is in- dependence for Northern Ireland. This initiative, de- signed to outflank loyalists and- republicans mired in...One such variation is the new Anglo-Irish accord, signed in November -1985, which is perhaps the most important political initiative in the province

Water quality studies of TV station reservoir at Davangere City, Karnataka (India).

PubMed

Begum, Nafeesa; Purushothama, R; Narayana, J; Kumar, K P Ravindra

2006-10-01

Studies were carried out to assess the water quality of TV station reservoir at Davangere City, Karnataka (India). The study revealed that there were variations in physico-chemical concentrations during the rainy season. Except turbidity, all the other physico-chemical characteristics were found within the permissible limits. The results were compared with the standards given by ISI for water quality.

Fit 5 Kids TV Reduction Program for Latino Preschoolers

PubMed Central

Mendoza, Jason A.; Baranowski, Tom; Jaramillo, Sandra; Fesinmeyer, Megan D.; Haaland, Wren; Thompson, Debbe; Nicklas, Theresa A.

2015-01-01

Introduction Reducing Latino preschoolers’ TV viewing is needed to reduce their risk of obesity and other chronic diseases. This study’s objective was to evaluate the Fit 5 Kids (F5K) TV reduction program’s impact on Latino preschooler’s TV viewing. Study design Cluster RCT with randomization at the center level and N=160 participants. Setting/participants Latino children aged 3–5 years and their parents were recruited from six Head Start centers in Houston, Texas, in 2010–2012 with analyses in 2013–2014. Intervention F5K was culturally adapted for Latino preschoolers and the overall goal was to reduce TV viewing. Study staff taught F5K over 7–8 weeks during the regular Head Start day directly to intervention students. Control schools provided the usual Head Start curriculum, which did not specifically cover TV viewing. Main outcome measures Individual-level outcomes were measured prior to (Time 1) and immediately following (Time 2) the intervention. The primary outcome, TV viewing (minutes/day), was measured by validated 7-day TV diaries (parent-reported). Sedentary time was measured by accelerometers. Results Per the adjusted repeated measures linear mixed effects model for TV viewing (minutes/day), intervention children decreased from 76.2 (9.9) at Time 1 to 52.1 (10.0) at Time 2, whereas control children remained about the same from 84.2 (10.5) at Time 1 to 85.4 (10.5) at Time 2. The relative difference from Time 1 to Time 2 was –25.3 (95% CI= –45.2, –5.4) minutes for intervention versus control children (N=160, p=0.01). In a similar adjusted model, there was a relative decrease in sedentary time (minutes/day) from Time 1 to Time 2 favoring the intervention children (–9.5, 95% CI= –23.0, 4.1), although not significant at p<0.05. Conclusions F5K reduced Latino preschoolers’ TV viewing by >25 minutes daily. These findings have implications for prevention of obesity, related disorders, and health equity. PMID:26572093

Self-help treatment for insomnia through television and book: a randomized trial.

PubMed

van Straten, Annemieke; Cuijpers, Pim; Smit, Filip; Spermon, Marianne; Verbeek, Ingrid

2009-01-01

Recently, a Dutch educational broadcasting company developed a 6 week self-help course for insomnia, which consists of a book and television programmes. In this study we examined its effects. 247 subjects with sleep problems were recruited through the media and randomized to the self-help treatment (n=126) or a waiting list control group (n=121). The intervention group received the book, and for 6 consecutive weeks a DVD or videotape. Subjects were assessed before and after the course. Both groups improved significantly with respect to sleep but there were no significant differences in improvements between the groups. However, the intervention group improved significantly more on secondary outcomes: the subjective evaluation of sleep quality (d=0.65), dysfunctional beliefs and attitudes about sleep (d=0.62), depressive symptoms (d=0.35), and quality of life (d=0.34). Cognitive-behavioral self-help treatment does not necessarily lead to sleep improvements but it does improve coping with insomnia. About 2% of the Dutch adult population has watched the regular broadcastings of the course after the trial ended. This huge number of viewers underlines that there is a need for this type of low cost self-help treatment.

Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis screening and treatment of pregnant women in Port-au-Prince, Haiti.

PubMed

Bristow, Claire C; Mathelier, Patricia; Ocheretina, Oksana; Benoit, Daphne; Pape, Jean W; Wynn, Adriane; Klausner, Jeffrey D

2017-10-01

In Haiti, routine screening for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) among pregnant women is not conducted; yet these sexually transmitted infections (STIs) are associated with adverse birth and newborn health outcomes. We aimed to assess the acceptability and feasibility of screening and the prevalence of STIs among pregnant women in Port-au-Prince, Haiti. Pregnant women of at least 18 years of age who attend Haitian Study Group for Kaposi's sarcoma and Opportunistic Infections (GHESKIO) clinics in Port-au-Prince, Haiti provided self-collected vaginal swab specimens. Laboratory testing was done with Xpert® CT/NG and Xpert® TV. The results of this study showed that of the 322 pregnant women who visited GHESKIO for their regular scheduled appointments, 300 (93.2%) consented for CT, NG, and TV testing. Of those, 107 women (35.7%) tested positive for at least one STI. There were 42 (14.7%) cases of CT, 8 (2.8%) NG, and 83 (29.0%) TV infections. Most infections were treated - 122 of 133 (91.7%). In summary, we found that it was highly acceptable and feasible to implement CT, NG, and TV screening among pregnant women in Port-au-Prince, Haiti. We found high prevalence of STIs among pregnant women, which suggest that STI screening in this population may be warranted.

[Television, advertising, and nutritional behavior of children].

PubMed

Schmitt, J; Voilquin, J P; Aubrège, A; Langinier, D

1989-06-01

The more and more prevalent misuse of custom of TV programs is a society's phenomenon, specially in the rich countries. This misuse is particularly dangerous for children, because of the implication of three factors: repercussion on health and familial climate, inauspicious impact of advertisings and nibling's phenomenon. Therefore, the children are manipulated, even if they keep a critical mind; in fact, they are very receptive, and by seduction-persuasion, they undergo an indoctrination according to the felt pleasure. In order to better understand the importance of this phenomenon day be day, an inquiry has been realised in school, near 509 pupils from 6 to 10 years old, in Moselle, and near they relatives, thanks to a questionnaire concerning the interdependance between TV, advertisings and nutritional behavior of children. The results demonstrate that more than 97% of children look at TV almost each day, the weekly average being about 25 hours, that's to say 2 H 40 the days with school and 5 H the free days. 75% of children practice the nibbling during the projection of programs. The power of advertising for foods is very strong: 75% of children eat them regularly. Then there is a defect of normal diet of children, under the pressure of a sure indoctrination induced by the advertisings. This is a social phenomenon capable to lead progressively to pathological consequences: obesity, cardio-vascular diseases, degenerative troubles.(ABSTRACT TRUNCATED AT 250 WORDS)

3D and 4D magnetic susceptibility tomography based on complex MR images

DOEpatents

Chen, Zikuan; Calhoun, Vince D

2014-11-11

Magnetic susceptibility is the physical property for T2*-weighted magnetic resonance imaging (T2*MRI). The invention relates to methods for reconstructing an internal distribution (3D map) of magnetic susceptibility values, .chi. (x,y,z), of an object, from 3D T2*MRI phase images, by using Computed Inverse Magnetic Resonance Imaging (CIMRI) tomography. The CIMRI technique solves the inverse problem of the 3D convolution by executing a 3D Total Variation (TV) regularized iterative convolution scheme, using a split Bregman iteration algorithm. The reconstruction of .chi. (x,y,z) can be designed for low-pass, band-pass, and high-pass features by using a convolution kernel that is modified from the standard dipole kernel. Multiple reconstructions can be implemented in parallel, and averaging the reconstructions can suppress noise. 4D dynamic magnetic susceptibility tomography can be implemented by reconstructing a 3D susceptibility volume from a 3D phase volume by performing 3D CIMRI magnetic susceptibility tomography at each snapshot time.

Imaging techniques for evaluation of the uterine cavity and endometrium in premenopausal patients before minimally invasive surgery.

PubMed

Dueholm, Margit; Lundorf, Erik; Olesen, Frede

2002-06-01

A literature review compared the diagnostic effectiveness and accuracy of transvaginal sonography (TVS) hysterosonographic examination (HSE), hysteroscopy (HY), and magnetic resonance imaging (MRI) in abnormalities of the uterine cavity and endometrium in premenopausal patients referred to surgery and women with abnormal uterine bleeding. The studies varied much in terms of patient selection, number of observers, blinding and experience of observers, and definition of abnormality criteria. The diagnostic effectiveness of the techniques reviewed varied: TVS only reached intermediate quality levels as a diagnostic tool for exclusion of uterine cavity abnormalities and no data support that MRI, TVS, HY, or HSE may exclude hyperplasia without concomitant endometrial sampling. HY and HSE were equally effective and apparently outperformed TVS, especially for identification of polyps. However, all techniques carried a significant number of false positive results. MRI does not satisfy current diagnostic demands for detection of endometrial abnormalities, but it is sufficiently accurate for submucous myoma (SM) evaluation. TVS, HSE, and HY carry much observer variation as opposed to MRI. In experienced hands TVS should be a first choice modality, but its precision and consistency fall short of current needs and it should therefore be supplemented by other techniques. HSE or HY performed by experienced clinicians should be used as supplements to TVS for exclusion of polyps. MRI can be recommended as the first choice modality for exact evaluation of SM uterine in-growth before advanced minimal invasive treatment of myomas. Clinicians should be aware that modern imaging techniques may yield highly idiosyncratic results when used by inexperienced staff, and efforts should be made to reduce such observer variation. Obstetricians & Gynecologists, Family Physicians. After completion of this article, the reader will be able to describe the diagnostic strengths and weaknesses of the various diagnostic tests in the evaluation of abnormal uterine bleeding and to compare the accuracy of each test to the others.

Chino del tomate virus:Relationships to Other Begomoviruses and Identification of A-Component Variants that Affect Symptom Expression.

PubMed

Brown, J K; Ostrow, K M; Idris, A M; Stenger, D C

2000-05-01

Phylogenetic and distance analyses place Chino del tomate virus (CdTV) in the New World clade of begomoviruses and indicate that CdTV and Tomato leaf crumple virus (TLCrV) are closely related strains of the same virus. One cloned CdTV A component (pCdTV-H6), when inoculated to tomato with the B component (pCdTV-B52), produced mild symptoms and low DNA titers. Another cloned CdTV A component (pCdTV-H8), when coinoculated to tomato with the B component, produced moderate leaf curling and veinal chlorosis similar to that of TLCrV. Coinoculation of both CdTV A components and the B component to tomato produced wild-type chino del tomate (CdT) disease symptoms consisting of severe leaf curling, veinal and interveinal chlorosis, and stunting. The two CdTV A components were nearly identical, except at nucleotide positions 1,722 and 2,324. The polymorphism at nucleotide 1,722 resulted in a change at Rep amino acid 261. The second polymorphism at nucleotide 2,324 resulted in changes at Rep amino acid 60 and AC4 amino acid 10. Two chimeric A components constructed by reciprocal exchange of a fragment bearing the polymorphic site at nucleotide 1,722 were evaluated for symptom phenotype. One chimeric A component (pCdTV-H86) produced wild-type CdT symptoms when coinoculated to tomato with the B component. The reciprocal chimeric A component (pCdTV-H68), when coin-oculated to tomato with the B component, also produced severe leaf curling, veinal chlorosis, and stunting. However, pCdTV-H68 induced less obvious interveinal chlorosis than wild-type or pCdTV-H86. Examination of A component genotypes recovered from tomato coinoculated with pCdTV-H6 and pCdTV-H8 indicated that recombination occurred to produce a genotype identical to pCdTV-H86. These results indicate that subtle genotypic variation has significant effects on symptom expression and may explain phenotypic differences observed among isolates and cloned DNAs of CdTV and TLCrV.

Temporal and radial variation of the solar wind temperature-speed relationship

NASA Astrophysics Data System (ADS)

Elliott, H. A.; Henney, C. J.; McComas, D. J.; Smith, C. W.; Vasquez, B. J.

2012-09-01

The solar wind temperature (T) and speed (V) are generally well correlated at ˜1 AU, except in Interplanetary Coronal Mass Ejections where this correlation breaks down. We perform a comprehensive analysis of both the temporal and radial variation in the temperature-speed (T-V) relationship of the non-transient wind, and our analysis provides insight into both the causes of the T-V relationship and the sources of the temperature variability. Often at 1 AU the speed-temperature relationship is well represented by a single linear fit over a speed range spanning both the slow and fast wind. However, at times the fast wind from coronal holes can have a different T-V relationship than the slow wind. A good example of this was in 2003 when there was a very large and long-lived outward magnetic polarity coronal hole at low latitudes that emitted wind with speeds as fast as a polar coronal hole. The long-lived nature of the hole made it possible to clearly distinguish that some holes can have a different T-V relationship. In an earlier ACE study, we found that both the compressions and rarefactions T-V curves are linear, but the compression curve is shifted to higher temperatures. By separating compressions and rarefactions prior to determining the radial profiles of the solar wind parameters, the importance of dynamic interactions on the radial evolution of the solar wind parameters is revealed. Although the T-V relationship at 1 AU is often well described by a single linear curve, we find that the T-V relationship continually evolves with distance. Beyond ˜2.5 AU the differences between the compressions and rarefactions are quite significant and affect the shape of the overall T-V distribution to the point that a simple linear fit no longer describes the distribution well. Since additional heating of the ambient solar wind outside of interaction regions can be associated with Alfvénic fluctuations and the turbulent energy cascade, we also estimate the heating rate radial profile from the solar wind speed and temperature measurements.

A promising limited angular computed tomography reconstruction via segmentation based regional enhancement and total variation minimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Wenkun; Zhang, Hanming; Li, Lei

2016-08-15

X-ray computed tomography (CT) is a powerful and common inspection technique used for the industrial non-destructive testing. However, large-sized and heavily absorbing objects cause the formation of artifacts because of either the lack of specimen penetration in specific directions or the acquisition of data from only a limited angular range of views. Although the sparse optimization-based methods, such as the total variation (TV) minimization method, can suppress artifacts to some extent, reconstructing the images such that they converge to accurate values remains difficult because of the deficiency in continuous angular data and inconsistency in the projections. To address this problem,more » we use the idea of regional enhancement of the true values and suppression of the illusory artifacts outside the region to develop an efficient iterative algorithm. This algorithm is based on the combination of regional enhancement of the true values and TV minimization for the limited angular reconstruction. In this algorithm, the segmentation approach is introduced to distinguish the regions of different image knowledge and generate the support mask of the image. A new regularization term, which contains the support knowledge to enhance the true values of the image, is incorporated into the objective function. Then, the proposed optimization model is solved by variable splitting and the alternating direction method efficiently. A compensation approach is also designed to extract useful information from the initial projections and thus reduce false segmentation result and correct the segmentation support and the segmented image. The results obtained from comparing both simulation studies and real CT data set reconstructions indicate that the proposed algorithm generates a more accurate image than do the other reconstruction methods. The experimental results show that this algorithm can produce high-quality reconstructed images for the limited angular reconstruction and suppress the illusory artifacts caused by the deficiency in valid data.« less

A promising limited angular computed tomography reconstruction via segmentation based regional enhancement and total variation minimization

NASA Astrophysics Data System (ADS)

Zhang, Wenkun; Zhang, Hanming; Li, Lei; Wang, Linyuan; Cai, Ailong; Li, Zhongguo; Yan, Bin

2016-08-01

X-ray computed tomography (CT) is a powerful and common inspection technique used for the industrial non-destructive testing. However, large-sized and heavily absorbing objects cause the formation of artifacts because of either the lack of specimen penetration in specific directions or the acquisition of data from only a limited angular range of views. Although the sparse optimization-based methods, such as the total variation (TV) minimization method, can suppress artifacts to some extent, reconstructing the images such that they converge to accurate values remains difficult because of the deficiency in continuous angular data and inconsistency in the projections. To address this problem, we use the idea of regional enhancement of the true values and suppression of the illusory artifacts outside the region to develop an efficient iterative algorithm. This algorithm is based on the combination of regional enhancement of the true values and TV minimization for the limited angular reconstruction. In this algorithm, the segmentation approach is introduced to distinguish the regions of different image knowledge and generate the support mask of the image. A new regularization term, which contains the support knowledge to enhance the true values of the image, is incorporated into the objective function. Then, the proposed optimization model is solved by variable splitting and the alternating direction method efficiently. A compensation approach is also designed to extract useful information from the initial projections and thus reduce false segmentation result and correct the segmentation support and the segmented image. The results obtained from comparing both simulation studies and real CT data set reconstructions indicate that the proposed algorithm generates a more accurate image than do the other reconstruction methods. The experimental results show that this algorithm can produce high-quality reconstructed images for the limited angular reconstruction and suppress the illusory artifacts caused by the deficiency in valid data.

SU-F-BRCD-09: Total Variation (TV) Based Fast Convergent Iterative CBCT Reconstruction with GPU Acceleration.

PubMed

Xu, Q; Yang, D; Tan, J; Anastasio, M

2012-06-01

To improve image quality and reduce imaging dose in CBCT for radiation therapy applications and to realize near real-time image reconstruction based on use of a fast convergence iterative algorithm and acceleration by multi-GPUs. An iterative image reconstruction that sought to minimize a weighted least squares cost function that employed total variation (TV) regularization was employed to mitigate projection data incompleteness and noise. To achieve rapid 3D image reconstruction (< 1 min), a highly optimized multiple-GPU implementation of the algorithm was developed. The convergence rate and reconstruction accuracy were evaluated using a modified 3D Shepp-Logan digital phantom and a Catphan-600 physical phantom. The reconstructed images were compared with the clinical FDK reconstruction results. Digital phantom studies showed that only 15 iterations and 60 iterations are needed to achieve algorithm convergence for 360-view and 60-view cases, respectively. The RMSE was reduced to 10-4 and 10-2, respectively, by using 15 iterations for each case. Our algorithm required 5.4s to complete one iteration for the 60-view case using one Tesla C2075 GPU. The few-view study indicated that our iterative algorithm has great potential to reduce the imaging dose and preserve good image quality. For the physical Catphan studies, the images obtained from the iterative algorithm possessed better spatial resolution and higher SNRs than those obtained from by use of a clinical FDK reconstruction algorithm. We have developed a fast convergence iterative algorithm for CBCT image reconstruction. The developed algorithm yielded images with better spatial resolution and higher SNR than those produced by a commercial FDK tool. In addition, from the few-view study, the iterative algorithm has shown great potential for significantly reducing imaging dose. We expect that the developed reconstruction approach will facilitate applications including IGART and patient daily CBCT-based treatment localization. © 2012 American Association of Physicists in Medicine.

The influence of television and film on interest in space and science

NASA Astrophysics Data System (ADS)

Jackson, Katrina Marie

Entertainment media has the great potential to inspire interest in the topics it presents. The purpose of this study is to better understand how entertainment media contributes to people's interests in space and science. There is a huge variety of science communication topics in previous literature, some of which deals with television and film, but very little that specifically study how television and film can inspire interest. A historical review of pioneers in the space industry shows that many were inspired by entertainment media, which at the time consisted of science fiction novels and magazines. In order to explore the possible relationships among influences for scientists and non-scientists and to determine specific questions for future research, I created and distributed an anonymous, online survey. The survey is suggestive, exploratory research using a convenience sampling method and is not meant to provide scientifically accurate statistics. 251 participants completed the survey; 196 were scientists and 55 were non-scientists. The survey showed that the participants did identify entertainment media as a major influencing factor, on a comparable level as factors such as classes or family members. Participants in space-related fields were influenced by entertainment media more than the participants in other fields were. I identified several questions for future research, such as: Are people in space-related fields inspired by entertainment media more than other scientists are? Are non-space-related scientists often inspired by space-related media? Do people who regularly watch science fiction tend to be more scientifically literate than average?

Sparse super-resolution reconstructions of video from mobile devices in digital TV broadcast applications

NASA Astrophysics Data System (ADS)

Boon, Choong S.; Guleryuz, Onur G.; Kawahara, Toshiro; Suzuki, Yoshinori

2006-08-01

We consider the mobile service scenario where video programming is broadcast to low-resolution wireless terminals. In such a scenario, broadcasters utilize simultaneous data services and bi-directional communications capabilities of the terminals in order to offer substantially enriched viewing experiences to users by allowing user participation and user tuned content. While users immediately benefit from this service when using their phones in mobile environments, the service is less appealing in stationary environments where a regular television provides competing programming at much higher display resolutions. We propose a fast super-resolution technique that allows the mobile terminals to show a much enhanced version of the broadcast video on nearby high-resolution devices, extending the appeal and usefulness of the broadcast service. The proposed single frame super-resolution algorithm uses recent sparse recovery results to provide high quality and high-resolution video reconstructions based solely on individual decoded frames provided by the low-resolution broadcast.

[Can family meals protect adolescents from obesity?].

PubMed

Tabak, Izabela; Jodkowska, Maria; Oblacińska, Anna; Mikiel-Kostyra, Krystyna

2012-01-01

To analyse the relationship between the frequency of family meals and the body weight of 13-year-olds and its selected determinants. The study was conducted in 2008 as the last stage in a prospective cohort study of 605 children. Questionnaires containing questions about the frequency of family meals, the general regularity of meals, fruit and vegetable consumption, physical activity and the number of hours spent watching television or at the computer were sent to 13-year-olds by mail. School nurses performed anthropometric measurements of the pupils' weight and height. Statistical analyses were performed, i.e. Pearson's correlations, the two-step cluster analysis and the logistic regression analysis. Most of the young people (80-90%) eat each of the main meals in the company of their parents at least once a week, 21% have breakfast with their parents every day, 41% - dinner, and 45% - supper. The frequency of family meals correlated negatively with the girls' BMI and the number of hours they spent watching television or at the computer, while positively with physical activity, regular meals and vegetable consumption in adolescents of both genders. The lowest mean values of BMI were found in a group of adolescents often eating family meals, the highest - in the group of young people who rarely ate family meals (over 20% of young people in this group were overweight), but the differences were statistically significant only for girls (p=0.025). The probability of less than 2 hours of sedentary behaviour daily, physical activity of at least 60 minutes per day and everyday vegetable and fruit consumption is twice as high in adolescents often consuming meals with their parents, and with the daily consumption of all the meals in this way - more than fourfold higher than in other groups. Family meals treated as a predictor of a healthy lifestyle can indirectly protect adolescents from overweight and obesity. Promoting family meals should be an important method of preventing obesity, particularly among teenage girls.

Children's exposure to food advertising on free-to-air television: an Asia-Pacific perspective.

PubMed

Kelly, Bridget; Hebden, Lana; King, Lesley; Xiao, Yang; Yu, Yang; He, Gengsheng; Li, Liangli; Zeng, Lingxia; Hadi, Hamam; Karupaiah, Tilakavati; Hoe, Ng See; Noor, Mohd Ismail; Yoon, Jihyun; Kim, Hyogyoo

2016-03-01

There is an established link between food promotions and children's food purchase and consumption. Children in developing countries may be more vulnerable to food promotions given the relative novelty of advertising in these markets. This study aimed to determine the scope of television food advertising to children across the Asia-Pacific to inform policies to restrict this marketing. Six sites were sampled, including from China, Indonesia, Malaysia and South Korea. At each site, 192 h of television were recorded (4 days, 16 h/day, three channels) from May to October 2012. Advertised foods were categorized as core/healthy, non-core/unhealthy or miscellaneous, and by product type. Twenty-seven percent of advertisements were for food/beverages, and the most frequently advertised product was sugar-sweetened drinks. Rates of non-core food advertising were highest during viewing times most popular with children, when between 3 (South Korea) and 15 (Indonesia) non-core food advertisements were broadcast each hour. Children in the Asia-Pacific are exposed to high volumes of unhealthy food/beverage television advertising. Different policy arrangements for food advertising are likely to contribute to regional variations in advertising patterns. Cities with the lowest advertising rates can be identified as exemplars of good policy practice. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Study of magnetic perturbations on SEC vidicon tubes. [large space telescope

NASA Technical Reports Server (NTRS)

Long, D. C.; Zucchino, P.; Lowrance, J.

1973-01-01

A laboratory measurements program was conducted to determine the tolerances that must be imposed to achieve optimum performance from SEC-vidicon data sensors in the LST mission. These measurements along with other data were used to formulate recommendations regarding the necessary telemetry and remote control for the television data sensors when in orbit. The study encompassed the following tasks: (1) Conducted laboratory measurements of the perturbations which an external magnetic field produces on a magnetically focused, SEC-vidicon. Evaluated shielding approaches. (2) Experimentally evaluated the effects produced on overall performance by variations of the tube electrode potentials, and the focus, deflection and alignment fields. (3) Recommended the extent of ground control of camera parameters and camera parameter telemetry required for optimizing the performance of the television system in orbit. The experimental data are summarized in a set of graphs.

Vitamin panacea: Is advertising fueling demand for products with uncertain scientific benefit?

PubMed

Eisenberg, Matthew D; Avery, Rosemary J; Cantor, Jonathan H

2017-09-01

This study examines the effect of advertising on demand for vitamins-products with spiraling sales despite little evidence of efficacy. We merge seven years (2003-2009) of advertising data from Kantar Media with the Simmons National Consumer Survey to estimate individual-level vitamin print and television ad exposure effects. Identification relies on exploiting exogenous variation in year-to-year advertising exposure by controlling for each individual's unique media consumption. We find that increasing advertising exposure from zero to the mean number of ads increases the probability of consumption by 1.2 and 0.8% points (or 2 and 1.4%) in print and television respectively. Stratifications by the presence of health conditions suggests that in print demand is being driven by both healthy and sick individuals. Copyright © 2017 Elsevier B.V. All rights reserved.

Uncommon presentations of tinea versicolor

PubMed Central

Varada, Sowmya; Dabade, Tushar; Loo, Daniel S.

2014-01-01

Tinea versicolor (TV) is a common cutaneous fungal infection characterized by superficial scaling and a mild disturbance of skin pigmentation. It typically affects the chest, upper back, and shoulders. However, involvement of more unusual regions of the body such as the face and scalp, arms and legs, intertriginous sites, genitalia, areolae, and palms and soles has been reported. This report details two such cases observed at our institution: a 32-year-old woman with involvement of the popliteal fossa and a 16-year-old boy with involvement of the groin. The clinician must be aware of these variations in location and perform the appropriate diagnostic workup when lesions have the characteristic morphology of TV despite an unusual location. The etiology, pathophysiology, and epidemiology of TV are reviewed and current literature describing other instances of TV in uncommon locations is discussed. PMID:25126470

Does Digital Video Advertising Increase Population-Level Reach of Multimedia Campaigns? Evidence From the 2013 Tips From Former Smokers Campaign

PubMed Central

Shafer, Paul R; Rodes, Robert; Kim, Annice; Hansen, Heather; Patel, Deesha; Coln, Caryn; Beistle, Diane

2016-01-01

Background Federal and state public health agencies in the United States are increasingly using digital advertising and social media to promote messages from broader multimedia campaigns. However, little evidence exists on population-level campaign awareness and relative cost efficiencies of digital advertising in the context of a comprehensive public health education campaign. Objective Our objective was to compare the impact of increased doses of digital video and television advertising from the 2013 Tips From Former Smokers (Tips) campaign on overall campaign awareness at the population level. We also compared the relative cost efficiencies across these media platforms. Methods We used data from a large national online survey of approximately 15,000 US smokers conducted in 2013 immediately after the conclusion of the 2013 Tips campaign. These data were used to compare the effects of variation in media dose of digital video and television advertising on population-level awareness of the Tips campaign. We implemented higher doses of digital video among selected media markets and randomly selected other markets to receive similar higher doses of television ads. Multivariate logistic regressions estimated the odds of overall campaign awareness via digital or television format as a function of higher-dose media in each market area. All statistical tests used the .05 threshold for statistical significance and the .10 level for marginal nonsignificance. We used adjusted advertising costs for the additional doses of digital and television advertising to compare the cost efficiencies of digital and television advertising on the basis of costs per percentage point of population awareness generated. Results Higher-dose digital video advertising was associated with 94% increased odds of awareness of any ad online relative to standard-dose markets (P<.001). Higher-dose digital advertising was associated with a marginally nonsignificant increase (46%) in overall campaign awareness regardless of media format (P=.09). Higher-dose television advertising was associated with 81% increased odds of overall ad awareness regardless of media format (P<.001). Increased doses of television advertising were also associated with significantly higher odds of awareness of any ad on television (P<.001) and online (P=.04). The adjusted cost of each additional percentage point of population-level reach generated by higher doses of advertising was approximately US $440,000 for digital advertising and US $1 million for television advertising. Conclusions Television advertising generated relatively higher levels of overall campaign awareness. However, digital video was relatively more cost efficient for generating awareness. These results suggest that digital video may be used as a cost-efficient complement to traditional advertising modes (eg, television), but digital video should not replace television given the relatively smaller audience size of digital video viewers. PMID:27627853

Does Digital Video Advertising Increase Population-Level Reach of Multimedia Campaigns? Evidence From the 2013 Tips From Former Smokers Campaign.

PubMed

Davis, Kevin C; Shafer, Paul R; Rodes, Robert; Kim, Annice; Hansen, Heather; Patel, Deesha; Coln, Caryn; Beistle, Diane

2016-09-14

Federal and state public health agencies in the United States are increasingly using digital advertising and social media to promote messages from broader multimedia campaigns. However, little evidence exists on population-level campaign awareness and relative cost efficiencies of digital advertising in the context of a comprehensive public health education campaign. Our objective was to compare the impact of increased doses of digital video and television advertising from the 2013 Tips From Former Smokers (Tips) campaign on overall campaign awareness at the population level. We also compared the relative cost efficiencies across these media platforms. We used data from a large national online survey of approximately 15,000 US smokers conducted in 2013 immediately after the conclusion of the 2013 Tips campaign. These data were used to compare the effects of variation in media dose of digital video and television advertising on population-level awareness of the Tips campaign. We implemented higher doses of digital video among selected media markets and randomly selected other markets to receive similar higher doses of television ads. Multivariate logistic regressions estimated the odds of overall campaign awareness via digital or television format as a function of higher-dose media in each market area. All statistical tests used the .05 threshold for statistical significance and the .10 level for marginal nonsignificance. We used adjusted advertising costs for the additional doses of digital and television advertising to compare the cost efficiencies of digital and television advertising on the basis of costs per percentage point of population awareness generated. Higher-dose digital video advertising was associated with 94% increased odds of awareness of any ad online relative to standard-dose markets (P<.001). Higher-dose digital advertising was associated with a marginally nonsignificant increase (46%) in overall campaign awareness regardless of media format (P=.09). Higher-dose television advertising was associated with 81% increased odds of overall ad awareness regardless of media format (P<.001). Increased doses of television advertising were also associated with significantly higher odds of awareness of any ad on television (P<.001) and online (P=.04). The adjusted cost of each additional percentage point of population-level reach generated by higher doses of advertising was approximately US $440,000 for digital advertising and US $1 million for television advertising. Television advertising generated relatively higher levels of overall campaign awareness. However, digital video was relatively more cost efficient for generating awareness. These results suggest that digital video may be used as a cost-efficient complement to traditional advertising modes (eg, television), but digital video should not replace television given the relatively smaller audience size of digital video viewers.

Access to mass media messages, and use of family planning in Nigeria: a spatio-demographic analysis from the 2013 DHS.

PubMed

Ajaero, Chukwuedozie K; Odimegwu, Clifford; Ajaero, Ijeoma D; Nwachukwu, Chidiebere A

2016-05-24

Nigeria has the highest population in sub-Saharan Africa with high birth and growth rates. There is therefore need for family planning to regulate and stabilize this population. This study examined the relationship between access to mass media messages on family planning and use of family planning in Nigeria. It also investigated the impacts of spatio-demographic variables on the relationship between access to mass media messages and use of family planning. Data from the 2013 demographic and health survey of Nigeria which was conducted in all the 36 states of Nigeria, and Abuja were used for the study. The sample was weighted to ensure representativeness. Univariate, bivariate and binary logistic regressions were conducted. The relationship between each of the access to mass media messages, and the family planning variables were determined with Pearson correlation analysis. The correlation results showed significant but weak direct relationships between the access to mass media messages and use of family planning at p < 0.0001 with access to television messages (r = 0.239) being associated with highest use of family planning. Some of the results of the adjusted regression analysis showed that access to television messages (OR = 1.2.225; p < 0.0001), and radio messages (OR = 1.945; p < 0.0001) increase the likelihood of the use of family planning. The adjusted regression model also indicated increased likelihood in the use of family planning by respondents with secondary education (OR = 2.709; p < 0.0001), the married (OR = 1.274; p < 0.001), and respondents within the highest wealth quintiles (OR = 3.442; p < 0.0001). There exist significant variations within spatio-demographic groups with regards to having access to mass media messages on family planning, and on the use of family planning. The results showed that access to mass media messages increases the likelihood of the use of family planning. Also people with higher socioeconomic status and those from the Southern part of the country make more use of family planning. There is need to improve the socioeconomic status of the populations. Also, the quality and regularity of mass media messages should be improved, while other communication avenues such as traditional institutions, blogs, and seminars for youths should be used to make family planning messages more acceptable.

Prevalence of obesity and associated risk factors among adolescents in Ankara, Turkey.

PubMed

Ercan, Sırma; Dallar, Yıldız Bilge; Önen, Serdar; Engiz, Özlem

2012-12-01

The purpose of this study was to investigate the prevalence of and the risk factors associated with obesity among adolescents in Ankara, Turkey. The study was conducted in 26 schools in Ankara during the time period from September 2010 to March 2011. A total of 8848 adolescents aged 11-18 years were chosen using a population-based stratified cluster sampling method. Body mass index (BMI) of the participants was compared with the BMI references for Turkish children and adolescents to estimate the prevalence of overweight and obesity. A standardized questionnaire aiming to determine the sociodemographic characteristics, computer use, television (TV) watching, physical activity, and presence of obesity in the family was applied to the study group. The results showed that the overall prevalence of obesity among adolescents was 7.7% (8.4 % for females and 7.0% for males). It was observed that BMI increased as computer use increased. A greater proportion of the overweight and obese adolescents watched TV and use computer for more than 2 hours/day as compared to their normal-weight counterparts. The normal-weight subjects were found to show a higher participation in regular physical activity. Obesity prevalence among the families of obese adolescents was 56.5%. The prevalence of adolescent obesity in Ankara, Turkey is lower as compared to many European countries and to the United States. Computer use, watching TV, physical activity and family factors are important risk factors for obesity.

Prevalence of Obesity and Associated Risk Factors Among Adolescents in Ankara, Turkey

PubMed Central

Ercan, Sırma; Dallar, Yıldız Bilge; Önen, Serdar; Engiz, Özlem

2012-01-01

Objective: The purpose of this study was to investigate the prevalence of and the risk factors associated with obesity among adolescents in Ankara, Turkey. Methods: The study was conducted in 26 schools in Ankara during the time period from September 2010 to March 2011. A total of 8848 adolescents aged 11-18 years were chosen using a population-based stratified cluster sampling method. Body mass index (BMI) of the participants was compared with the BMI references for Turkish children and adolescents to estimate the prevalence of overweight and obesity. A standardized questionnaire aiming to determine the sociodemographic characteristics, computer use, television (TV) watching, physical activity, and presence of obesity in the family was applied to the study group. Results: The results showed that the overall prevalence of obesity among adolescents was 7.7% (8.4 % for females and 7.0% for males). It was observed that BMI increased as computer use increased. A greater proportion of the overweight and obese adolescents watched TV and use computer for more than 2 hours/day as compared to their normal-weight counterparts. The normal-weight subjects were found to show a higher participation in regular physical activity. Obesity prevalence among the families of obese adolescents was 56.5%. Conclusions: The prevalence of adolescent obesity in Ankara, Turkey is lower as compared to many European countries and to the United States. Computer use, watching TV, physical activity and family factors are important risk factors for obesity. Conflict of interest:None declared. PMID:23149433

Developmental Trajectories of Physical Activity, Sports, and Television Viewing During Childhood to Young Adulthood: Iowa Bone Development Study.

PubMed

Kwon, Soyang; Janz, Kathleen F; Letuchy, Elena M; Burns, Trudy L; Levy, Steven M

2015-07-01

The diverse developmental patterns of obesogenic behaviors during childhood and adolescence can be better understood by using new analytic approaches to assess the heterogeneity in variation during growth and development and to map the clustering of behavior patterns. To identify distinct trajectories of daily time spent in moderate- to vigorous-intensity physical activity (MVPA) from ages 5 to 19 years and to examine the associations of MVPA trajectories with sports participation and television viewing trajectories. Cohort members in the prospective population-based Iowa Bone Development Study participated in MVPA assessments via accelerometry from September 16, 1998, to December 9, 2013, at ages 5, 8, 11, 13, 15, 17, and 19 years and completed a questionnaire every 6 months on sports participation and daily time spent in television viewing. Trajectories of MVPA (minutes per day), participation in organized sports (yes or no), and television viewing time (hours per day). Based on the data from 537 participants (50.1% females; 94.6% white), we identified 4 MVPA trajectories: consistently inactive (14.9%), consistently active (18.1%), decreasing moderate physical activity (52.9%), and substantially decreasing high physical activity (14.1%). All participants in the consistently inactive trajectory also followed a trajectory of no participation in sports. The consistently active trajectory was associated with decreasing an already low television viewing trajectory (P < .001). This study provided a nuanced look at the known decrease in MVPA during childhood and adolescence. Sports participation could be a critical way to avoid the consistently inactive pattern. Most important, we identified a subset of participants who maintained a seemingly healthy level of MVPA from childhood to young adulthood. The developmental pathways of physical activity and television viewing behaviors could be related. Additional studies should examine the determinants and health consequences of these specific MVPA trajectories.

Physical activity barriers and enablers in older Veterans with lower-limb amputation.

PubMed

Littman, Alyson J; Boyko, Edward J; Thompson, Mary Lou; Haselkorn, Jodie K; Sangeorzan, Bruce J; Arterburn, David E

2014-01-01

Little is known about the types of physical activities that older individuals with lower-limb loss perform, correlates of regular physical activity (PA), and barriers and facilitators to PA. We conducted an exploratory study in 158 older Veterans from the Pacific Northwest with a partial foot (35%), below-knee (39%) and above-knee (26%) amputation. Ninety-eight percent of survey respondents were male, on average 65 yr of age and 15 yr postamputation; 36% of amputations were trauma-related. The most commonly reported physical activities were muscle strengthening (42%), yard work and/or gardening (30%), and bicycling (11%). Forty-three percent were classified as physically active based on weekly moderate- and vigorous-intensity PA. History of vigorous preamputation PA was positively associated with being active, while low wealth and watching ≥5 h/d of television/videos were inversely associated. While pain- and resource-related barriers to PA were most frequently reported, only knowledge-related and interest/motivation-related barriers were inversely associated with being active. Family support and financial assistance to join a gym were the most commonly reported factors that would facilitate PA. To increase PA in the older amputee population, interventions should address motivational issues, knowledge gaps, and television watching; reduce financial barriers to exercising; and consider involving family members.

Physical activity and abdominal obesity in youth.

PubMed

Kim, YoonMyung; Lee, SoJung

2009-08-01

Childhood obesity continues to escalate despite considerable efforts to reverse the current trends. Childhood obesity is a leading public health concern because overweight-obese youth suffer from comorbidities such as type 2 diabetes mellitus, nonalcoholic fatty liver disease, metabolic syndrome, and cardiovascular disease, conditions once considered limited to adults. This increasing prevalence of chronic health conditions in youth closely parallels the dramatic increase in obesity, in particular abdominal adiposity, in youth. Although mounting evidence in adults demonstrates the benefits of regular physical activity as a treatment strategy for abdominal obesity, the independent role of regular physical activity alone (e.g., without calorie restriction) on abdominal obesity, and in particular visceral fat, is largely unclear in youth. There is some evidence to suggest that, independent of sedentary activity levels (e.g., television watching or playing video games), engaging in higher-intensity physical activity is associated with a lower waist circumference and less visceral fat. Several randomized controlled studies have shown that aerobic types of exercise are protective against age-related increases in visceral adiposity in growing children and adolescents. However, evidence regarding the effect of resistance training alone as a strategy for the treatment of abdominal obesity is lacking and warrants further investigation.

Hospital doctors' Opinions regarding educational Utility, public Sentiment and career Effects of Medical television Dramas: the HOUSE MD study.

PubMed

Haboubi, Hasan N; Morgan, Holly; Aldalati, Omar

2015-12-14

To evaluate the opinions of practicing clinicians on medical television dramas and the effects these series have on society as well as their own practice. Observational study using a structured questionnaire disseminated among doctors of all grades and specialties at one tertiary centre and two large secondary care district general hospitals in Wales, United Kingdom. Three hundred and seventy-two questionnaires were distributed over a 3-month period, with 200 completed questionnaires received (response rate, 54%). Frequency and reasons for watching these programs, and opinions regarding realism, educational value and public perception, evaluated by doctors' grades and specialties. Identification of work practice with any observed traits in fictional doctors was also analysed. 65% of doctors surveyed admitted to watching these programs on more than one occasion. Junior doctors (interns and resident medical officers) were more regular viewers. Most doctors who admitted to watching medical dramas did so for entertainment purposes (69%); 8% watched for educational purposes and, of these, 100% watched House MD, 82% felt that these dramas were unrepresentative of daily practice, and 10% thought that they accurately portrayed reality. Most of the positive responses were from junior doctors. 61% of doctors identified some aspect of their clinical practice with another doctor (fictional or non-fictional; most junior doctors identified with a fictional doctor, compared with non-fictional role models for more senior practicing clinicians. This survey shows that a large body of the medical workforce watches medical television dramas and that such programs exercise a growing influence on the practice of junior doctors, particularly those in physicianly specialties. The reasons for certain role model selections remain unknown and may require further evaluation.

[Sedentary behaviour 13-years-olds and its association with selected health behaviours, parenting practices and body mass].

PubMed

Jodkowska, Maria; Tabak, Izabela; Oblacińska, Anna; Stalmach, Magdalena

2013-01-01

1. To estimate the time spent in sedentary behaviour (watching TV, using the computer, doing homework). 2. To assess the link between the total time spent on watching TV, using the computer, doing homework and dietary habits, physical activity, parental practices and body mass. Cross-sectional study was conducted in Poland in 2008 among 13-year olds (n=600). They self-reported their time of TV viewing, computer use and homework. Their dietary behaviours, physical activity (MVPA) and parenting practices were also self-reported. Height and weight were measured by school nurses. Descriptive statistics and correlation were used in this analysis. The mean time spent watching television in school days was 2.3 hours for girls and 2.2 for boys. Boys spent significantly more time using the computer than girls - respectively 1.8 and 1.5 hours, while girls took longer doing homework - respectively 1.7 and 1.3 hours. Mean screen time was about 4 hours in school days and about 6 hours during weekend, statistically longer for boys in weekdays. Screen time was positively associated with intake of sweets, chips, soft drinks, "fast food" and meals consumption during TV, and negatively with regularity of meals and parental supervision. There was no correlation between screen time with physical activity and body mass. Sedentary behaviours and physical activity are not competing behaviours in Polish teenagers, but their relationship with unhealthy dietary patterns may lead to development of obesity. Good parental practices, both mother's and father's supervision seems to be crucial for screen time limitation in their children. Parents should become aware that relevant lifestyle monitoring of their children is a crucial element of health education in prevention of civilization diseases. This is a task for both healthcare workers and educational staff.

A spatially-variant deconvolution method based on total variation for optical coherence tomography images

NASA Astrophysics Data System (ADS)

Almasganj, Mohammad; Adabi, Saba; Fatemizadeh, Emad; Xu, Qiuyun; Sadeghi, Hamid; Daveluy, Steven; Nasiriavanaki, Mohammadreza

2017-03-01

Optical Coherence Tomography (OCT) has a great potential to elicit clinically useful information from tissues due to its high axial and transversal resolution. In practice, an OCT setup cannot reach to its theoretical resolution due to imperfections of its components, which make its images blurry. The blurriness is different alongside regions of image; thus, they cannot be modeled by a unique point spread function (PSF). In this paper, we investigate the use of solid phantoms to estimate the PSF of each sub-region of imaging system. We then utilize Lucy-Richardson, Hybr and total variation (TV) based iterative deconvolution methods for mitigating occurred spatially variant blurriness. It is shown that the TV based method will suppress the so-called speckle noise in OCT images better than the two other approaches. The performance of proposed algorithm is tested on various samples, including several skin tissues besides the test image blurred with synthetic PSF-map, demonstrating qualitatively and quantitatively the advantage of TV based deconvolution method using spatially-variant PSF for enhancing image quality.

New astronomy space experiments with television scanning.

NASA Technical Reports Server (NTRS)

Davis, R. J.

1971-01-01

Application of data from the Celescope Catalog of Ultraviolet Observations to various problems of stellar and interstellar astrophysics. These include refinements in the incorporation of line blanketing in theoretical stellar-atmosphere models, variations in the law of interstellar extinction from one region of the sky to another, and selection and identification of various types of peculiar stars for further investigation. In addition, the data were analyzed to determine the photometric and astrometric accuracy of the Celescope equipment.

Prevalence and causes of low birth weight in India.

PubMed

Bharati, P; Pal, M; Bandyopadhyay, M; Bhakta, A; Chakraborty, S; Bharati, P

2011-12-01

The aims of the study are (i) to understand inter-zone and interstate variation of low birth weight (LBW) and (ii) to determine the key variables to reduce LBW in India. Using the latest National Family Health Survey (NFHS) data of 2005-06 which showed the percentage distribution of LBW infants, ANOVA and post-hoc test were performed to determine the spatial variation of birth weight. The covariates which influence LBW fell into three categories: (i) social variables which included location, mother's education, religion, access of mothers to newspapers, television and family structure; (ii) economic variable namely, the wealth index, and (iii) biological variables which consisted of sex of the children, birth order, and mother's body mass index (BMI). Three models of Logistic regression were carried out to examine the influence of the combinations of these direct and indirect factors. In India, nearly 20% of new borns have LBW. Males have less frequency of LBW than females. The North-east zone has the lowest prevalence of LBW while the north zone has the highest. Mother's education, access to TV and nuclear family, and intake of iron tablets are the most important socio-economic influences on the determination of birth weight in India. It is essential to provide proper diet and nutritional care of mothers during pregnancy. Increased education of mothers through programmes in TV and newspapers articles have significant roles to play in reducing LBW in India.

Monochromatic-beam-based dynamic X-ray microtomography based on OSEM-TV algorithm.

PubMed

Xu, Liang; Chen, Rongchang; Yang, Yiming; Deng, Biao; Du, Guohao; Xie, Honglan; Xiao, Tiqiao

2017-01-01

Monochromatic-beam-based dynamic X-ray computed microtomography (CT) was developed to observe evolution of microstructure inside samples. However, the low flux density results in low efficiency in data collection. To increase efficiency, reducing the number of projections should be a practical solution. However, it has disadvantages of low image reconstruction quality using the traditional filtered back projection (FBP) algorithm. In this study, an iterative reconstruction method using an ordered subset expectation maximization-total variation (OSEM-TV) algorithm was employed to address and solve this problem. The simulated results demonstrated that normalized mean square error of the image slices reconstructed by the OSEM-TV algorithm was about 1/4 of that by FBP. Experimental results also demonstrated that the density resolution of OSEM-TV was high enough to resolve different materials with the number of projections less than 100. As a result, with the introduction of OSEM-TV, the monochromatic-beam-based dynamic X-ray microtomography is potentially practicable for the quantitative and non-destructive analysis to the evolution of microstructure with acceptable efficiency in data collection and reconstructed image quality.

Improving IMRT delivery efficiency with reweighted L1-minimization for inverse planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hojin; Becker, Stephen; Lee, Rena

2013-07-15

Purpose: This study presents an improved technique to further simplify the fluence-map in intensity modulated radiation therapy (IMRT) inverse planning, thereby reducing plan complexity and improving delivery efficiency, while maintaining the plan quality.Methods: First-order total-variation (TV) minimization (min.) based on L1-norm has been proposed to reduce the complexity of fluence-map in IMRT by generating sparse fluence-map variations. However, with stronger dose sparing to the critical structures, the inevitable increase in the fluence-map complexity can lead to inefficient dose delivery. Theoretically, L0-min. is the ideal solution for the sparse signal recovery problem, yet practically intractable due to its nonconvexity of themore » objective function. As an alternative, the authors use the iteratively reweighted L1-min. technique to incorporate the benefits of the L0-norm into the tractability of L1-min. The weight multiplied to each element is inversely related to the magnitude of the corresponding element, which is iteratively updated by the reweighting process. The proposed penalizing process combined with TV min. further improves sparsity in the fluence-map variations, hence ultimately enhancing the delivery efficiency. To validate the proposed method, this work compares three treatment plans obtained from quadratic min. (generally used in clinic IMRT), conventional TV min., and our proposed reweighted TV min. techniques, implemented by a large-scale L1-solver (template for first-order conic solver), for five patient clinical data. Criteria such as conformation number (CN), modulation index (MI), and estimated treatment time are employed to assess the relationship between the plan quality and delivery efficiency.Results: The proposed method yields simpler fluence-maps than the quadratic and conventional TV based techniques. To attain a given CN and dose sparing to the critical organs for 5 clinical cases, the proposed method reduces the number of segments by 10-15 and 30-35, relative to TV min. and quadratic min. based plans, while MIs decreases by about 20%-30% and 40%-60% over the plans by two existing techniques, respectively. With such conditions, the total treatment time of the plans obtained from our proposed method can be reduced by 12-30 s and 30-80 s mainly due to greatly shorter multileaf collimator (MLC) traveling time in IMRT step-and-shoot delivery.Conclusions: The reweighted L1-minimization technique provides a promising solution to simplify the fluence-map variations in IMRT inverse planning. It improves the delivery efficiency by reducing the entire segments and treatment time, while maintaining the plan quality in terms of target conformity and critical structure sparing.« less

Music recognition by Japanese children with cochlear implants.

PubMed

Nakata, Takayuki; Trehub, Sandra E; Mitani, Chisato; Kanda, Yukihiko; Shibasaki, Atsuko; Schellenberg, E Glenn

2005-01-01

Congenitally deaf Japanese children with cochlear implants were tested on their recognition of theme songs from television programs that they watched regularly. The children, who were 4-9 years of age, attempted to identify each song from a closed set of alternatives. Their song identification ability was examined in the context of the original commercial recordings (vocal plus instrumental), the original versions without the words (i.e., karaoke versions), and flute versions of the melody. The children succeeded in identifying the music only from the original versions, and their performance was related to their music listening habits. Children gave favorable appraisals of the music even when they were unable to recognize it. Further research is needed to find means of enhancing cochlear implants users' perception and appreciation of music.

System designed for issuing landslide alerts in the San Francisco Bay area

USGS Publications Warehouse

Finley, D.

1987-01-01

A system for forecasting landslides during major storms has been developed for the San Francisco Bay area by the U.S Geological Survey and was successfully tested during heavy storms in the bay area during February 1986. Based on the forecasts provided by the USGS, the National Weather Service (NWS) included landslide warnings in its regular weather forecasts or in special weather statements transmitted to local radio and television stations and other news media. USGS scientists said the landslide forecasting and warning system for the San Francisco Bay area can be used as a prototype in developing similar systems for other parts of the Nation susceptible to landsliding. Studies show damage from landslides in the United States averages an estimated $1.5 billion per year. 

Elderly Americans and the Internet: E-Mail, TV News, Information and Entertainment Websites

ERIC Educational Resources Information Center

Hilt, Michael L.; Lipschultz, Jeremy H.

2004-01-01

Older Americans, like other groups, vary in their use of the Internet. The participants for this study-elderly computer users from a Midwestern mid-size sample-used e-mail and considered it the most important Internet function. It was common for them to use e-mail with family and friends on a regular, if not daily, basis. When this group of older…

Elderly Americans and the Internet: E-Mail, TV News, Information and Entertainment Websites

ERIC Educational Resources Information Center

Hilt, Michael L.; Lipschultz, Jeremy H.

2004-01-01

Older Americans, like other groups, vary in their use of the Internet. The participants for this study--elderly computer users from a Midwestern mid-size sample--used e-mail and considered it the most important Internet function. It was common for them to use e-mail with family and friends on a regular, if not daily, basis. When this group of…

Exposure of children and adolescents to alcohol advertising on Australian metropolitan free-to-air television.

PubMed

Fielder, Lynda; Donovan, Robert J; Ouschan, Robyn

2009-07-01

This study investigated the exposure of underage youth to alcohol television advertising on metropolitan free-to-air television in the five mainland capital city markets of Australia. Exposure levels (target audience rating points; TARPs) were obtained for all alcohol advertisements screened from November 2005 to October 2006 in each capital city market for: children 0-12 years; underage teens 13-17 years; young adults 18-24 years; and mature adults 25+ years. The 30 most exposed advertisements across age groups were then content-analysed for elements appealing to children and underage youth. In each of the five metropolitan markets, mature adults were most exposed to alcohol advertising. Children were exposed to one-third the level of mature adults and underage teens to approximately the same level as young adults. However, there was considerable variation in media weight between markets, such that underage teens in two markets had higher advertising TARPs than young adults in other markets. All 30 highest exposed advertisements contained at least one element known to appeal to children and underage youth, with 23 containing two or more such elements. Fifteen of the 30 advertisements featured an animal. The self-regulation system in Australia does not protect children and youth from exposure to alcohol advertising, much of which contains elements appealing to these groups.

The effect of variable S/N on the subjective evaluation of protection ratios for direct-TV satellite services

NASA Technical Reports Server (NTRS)

Groumpos, P. P.; Dimitriadis, B. D.; Whyte, W.

1984-01-01

Protection ratios, the ratio of wanted-to-unwanted signal power at the receiver input, for acceptable picture quality were experimentally evaluated for four different still pictures. The variation of carrier-to-interference, C/I, with picture impairment grade is investigated when different noise levels are present. Results are presented which show the relationship between the impairment grade and the C/I ratio for FM/TV co-channel systems under variable S/N conditions.

Physical activity, health, body mass index, sleeping habits and body complaints in Australian senior high school students.

PubMed

Alricsson, Marie; Domalewski, Debra; Romild, Ulla; Asplund, Ragnar

2008-01-01

Adolescents in the industrial world are becoming less physically active and are increasingly adopting a sedentary life-style in front of computers and television screens. to determine self-related health, physical activity, sleeping habits, prevalence of overweight, and body complaints in Australian senior high school students. Participants were 466 high school students aged 15-17 years enrolled in academic and vocational programs. A questionnaire was completed at two senior high schools with questions about weight and height, health, physical activity, type of physical activity/sport, intensity, sleeping habits, and possible injuries or complaints during the last three months. Seventy seven percent of the high school students participated in sports on a regular basis. Compared with vocational programs, more males and females in academic programs participated in sports (71% and 80% respectively) (p = .036). Males reported significantly better health than females (p < .0001). 65% of the study group reported body complaints during the last 3 months. A higher number of females than males reported complaints about the back (p = .007) and the hip (p = .05). Good sleep was reported in 82.1% of males and in 76.6% of females. In males, 44.3% were often sleepy in the daytime (females 56.6%, p < .01). Underweight, physical activity and good sleep are factors with significant positive effect on good health, whereas overweight is a negative factor. Proper sleep habits and higher physical activity levels should be promoted among high school students, and TV viewing time and video game use restricted. Additionally, schools should provide opportunities for young people to participate in a wider range of physical activities that address their individual needs while promoting the health benefits of engaging in regular exercise.

Obesogenic television food advertising to children in Malaysia: sociocultural variations

PubMed Central

Ng, See H.; Kelly, Bridget; Se, Chee H.; Chinna, Karuthan; Sameeha, Mohd Jamil; Krishnasamy, Shanthi; MN, Ismail; Karupaiah, Tilakavati

2014-01-01

Background Food advertising on television (TV) is well known to influence children's purchasing requests and models negative food habits in Western countries. Advertising of unhealthy foods is a contributor to the obesogenic environment that is a key driver of rising rates of childhood obesity. Children in developing countries are more at risk of being targeted by such advertising, as there is a huge potential for market growth of unhealthy foods concomitant with poor regulatory infrastructure. Further, in developing countries with multi-ethnic societies, information is scarce on the nature of TV advertising targeting children. Objectives To measure exposure and power of TV food marketing to children on popular multi-ethnic TV stations in Malaysia. Design Ethnic-specific popular TV channels were identified using industry data. TV transmissions were recorded for each channel from November 2012 to August 2013 (16 hr/day) for randomly selected weekdays and weekend days during normal days and repeated during school holidays (n=88 days). Coded food/beverage advertisements were grouped into core (healthy), non-core (non-healthy), or miscellaneous (unclassified) food categories. Peak viewing time (PVT) and persuasive marketing techniques were identified. Results Non-core foods were predominant in TV food advertising, and rates were greater during school holidays compared to normal days (3.51 vs 1.93 food ads/hr/channel, p<0.001). During normal days’ PVT, the ratio of non-core to core food advertising was higher (3.25 food ads/hr/channel), and this more than trebled during school holidays to 10.25 food ads/hr/channel. Popular channels for Indian children had the lowest rate of food advertising relative to other ethnic groups. However, sugary drinks remained a popular non-core product advertised across all broadcast periods and channels. Notably, promotional characters doubled for non-core foods during school holidays compared to normal days (1.91 vs 0.93 food ads/hr/channel, p<0.001). Conclusions This study highlights non-core food advertising, and predominantly sugary drinks are commonly screened on Malaysian TV channels. The majority of these sugary drinks were advertised by multinational companies, and this observation warrants regulatory attention. PMID:25141835

Obesogenic television food advertising to children in Malaysia: sociocultural variations.

PubMed

Ng, See H; Kelly, Bridget; Se, Chee H; Chinna, Karuthan; Sameeha, Mohd Jamil; Krishnasamy, Shanthi; Ismail, M N; Karupaiah, Tilakavati

2014-01-01

Food advertising on television (TV) is well known to influence children's purchasing requests and models negative food habits in Western countries. Advertising of unhealthy foods is a contributor to the obesogenic environment that is a key driver of rising rates of childhood obesity. Children in developing countries are more at risk of being targeted by such advertising, as there is a huge potential for market growth of unhealthy foods concomitant with poor regulatory infrastructure. Further, in developing countries with multi-ethnic societies, information is scarce on the nature of TV advertising targeting children. To measure exposure and power of TV food marketing to children on popular multi-ethnic TV stations in Malaysia. Ethnic-specific popular TV channels were identified using industry data. TV transmissions were recorded for each channel from November 2012 to August 2013 (16 hr/day) for randomly selected weekdays and weekend days during normal days and repeated during school holidays (n=88 days). Coded food/beverage advertisements were grouped into core (healthy), non-core (non-healthy), or miscellaneous (unclassified) food categories. Peak viewing time (PVT) and persuasive marketing techniques were identified. Non-core foods were predominant in TV food advertising, and rates were greater during school holidays compared to normal days (3.51 vs 1.93 food ads/hr/channel, p<0.001). During normal days' PVT, the ratio of non-core to core food advertising was higher (3.25 food ads/hr/channel), and this more than trebled during school holidays to 10.25 food ads/hr/channel. Popular channels for Indian children had the lowest rate of food advertising relative to other ethnic groups. However, sugary drinks remained a popular non-core product advertised across all broadcast periods and channels. Notably, promotional characters doubled for non-core foods during school holidays compared to normal days (1.91 vs 0.93 food ads/hr/channel, p<0.001). This study highlights non-core food advertising, and predominantly sugary drinks are commonly screened on Malaysian TV channels. The majority of these sugary drinks were advertised by multinational companies, and this observation warrants regulatory attention.

TV viewing and obesity among Norwegian children: the importance of parental education.

PubMed

Kristiansen, Hege; Júlíusson, Pétur B; Eide, Geir E; Roelants, Mathieu; Bjerknes, Robert

2013-02-01

To analyse the effect of lifestyle factors on the prevalence of overweight and obesity in 6-15-year-old Norwegian children. Questionnaire data on lifestyle factors (sedentary behaviour, activity and eating habits) and prevalence numbers of overweight and obesity based on measured height and weight were analysed using multinomial logistic regression in a sample of 2281 children included in the Bergen Growth Study. More screen time increased the risk of overweight (odds ratio (OR): 1.25; p = 0.02) and obesity (OR: 1.12; p = 0.02) as did the presence of a TV in the child's bedroom (OR: 1.26 (overweight), OR: 1.81 (obese); p = 0.04). The obese children reported less sugar intake than the not overweight children (OR: 0.58; p = 0.01). Higher parental education was associated with less screen time (p = 0.02), lower frequency of TV in the child's bedroom (p = 0.001), more sports (p = 0.005), as well as eating more fruit and vegetables, less sweets, soft drinks and fast food, and more regular meals (for all, p < 0.03). Indicators of sedentary lifestyle, such as screen time and the presence of a TV in the child's bedroom, were associated with overweight and obesity in Norwegian schoolchildren. Higher parental education was generally associated with less obesogenic lifestyle. ©2012 The Author(s)/Acta Paediatrica ©2012 Foundation Acta Paediatrica.

National data showed that delayed sleep in six-year-old children was associated with excessive use of electronic devices at 12 years.

PubMed

Kato, Tsuguhiko; Yorifuji, Takashi; Yamakawa, Michiyo; Inoue, Sachiko

2018-01-31

Cross-sectional studies have shown associations between adolescent sleep problems and the use of electronic devices, such as mobile phones, but longitudinal studies remain scarce. We explored any association between delayed bedtimes at six years old and the excessive use of electronic devices at 12 years of age. Texting was a prime focus. We analysed 9607 adolescents who owned mobile phones in 2013 using the Japanese Longitudinal Survey of Newborns in the 21st Century, which started in 2001. The outcomes were daily excessive use of a mobile phone, television (TV) and video games. Delayed bedtime at the age of six years was associated with excessive texting at weekends. The adjusted odds ratios and 95% confidence intervals obtained from logistic regression analyses were 1.88 (1.14-3.10) for the 10-11 pm group and 1.98 (1.08-3.63) for the after 11 pm group, compared with the before 9 pm group. Later bedtimes were also associated with increased risks of excessive TV viewing and video game use. Our study indicated that six-year-olds who regularly stayed up late at night used electronic devices more frequently, or for longer, at the age of 12. Parents need to be more aware of links between sleep issues and electronic devices. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Coexistence of risk behaviors for being overweight among Brazilian adolescents.

PubMed

Ferreira, Nathália Luíza; Claro, Rafael Moreira; Mingoti, Sueli Aparecida; Lopes, Aline Cristine Souza

2017-07-01

This study aimed to evaluate the magnitude of and the factors associated with the coexistence of risk behaviors for being overweight among Brazilian adolescents. This is a cross-sectional study with a representative sample of adolescents (mostly aged 13-15years) enrolled from public and private schools of Brazil in 2012. The co-occurring sedentary behavior and inadequate food consumption (regular intake of sugary and fried foods, and irregular consumption of fruits and vegetables-FV) was estimated using a Venn diagram. Sociodemographic, familial, and behavioral factors associated with the number of risk behaviors for being overweight were identified using an ordinal logistic regression analysis. Sedentary behavior was observed in 62.0% of adolescents. Regular intake of sugary or fried food was observed in 55.3% and 23.5% of adolescents, respectively, with 51.9% having an inadequate intake of FV. At least one risk behavior was reported in >90.0% of adolescents; 6.1% reported all 4. Being female, having a higher maternal education level, attending private school, not having breakfast or meals with parents regularly, eat watching television, and not practicing weekly leisure time physical activity were associated with an increased chance of having multiple risk behaviors. This study observed a high prevalence of coexisting of risk behaviors, which was associated with sociodemographic, familial, and behavioral factors. These findings may contribute to a clearer understanding of the associations between different behaviors among adolescents, and may be used to improve public health surveillance and to develop strategies that address multiple behaviors, in order to prevent overweight among adolescents. Copyright © 2017 Elsevier Inc. All rights reserved.

Telling stories about abortion: abortion-related plots in American film and television, 1916-2013.

PubMed

Sisson, Gretchen; Kimport, Katrina

2014-05-01

Popular discourse on abortion in film and television assumes that abortions are under- and misrepresented. Research indicates that such representations influence public perception of abortion care and may play a role in the production of social myths around abortion, with consequences for women's experience of abortion. To date, abortion plotlines in American film and television have not been systematically tracked and analyzed. A comprehensive online search was conducted to identify all representations of pregnancy decision making and abortion in American film and television through January 2013. Search results were coded for year, pregnancy decision and mortality outcome. A total of 310 plotlines were identified, with an overall upward trend over time in the number of representations of abortion decision making. Of these plotlines, 173 (55.8%) resulted in abortion, 80 (25.8%) in parenting, 13 (4.2%) in adoption and 21 (6.7%) in pregnancy loss, and 16 (5.1%) were unresolved. A total of 13.5% (n=42) of stories ended with the death of the woman who considered an abortion, whether or not she obtained one. Abortion-related plotlines occur more frequently than popular discourse assumes. Year-to-year variation in frequency suggests an interactive relationship between media representations, cultural attitudes and policies around abortion regulation, consistent with cultural theory of the relationship between media products and social beliefs. Patterns of outcomes and rates of mortality are not representative of real experience and may contribute to social myths around abortion. The narrative linking of pregnancy termination with mortality is of particular note, supporting the social myth associating abortion with death. This analysis empirically describes the number of abortion-related plotlines in American film and television. It contributes to the systematic evaluation of the portrayal of abortion in popular culture and provides abortion care professionals and advocates with an initial accurate window into cultural stories being told about abortion. Copyright © 2014 Elsevier Inc. All rights reserved.

Combined iterative reconstruction and image-domain decomposition for dual energy CT using total-variation regularization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Xue; Niu, Tianye; Zhu, Lei, E-mail: leizhu@gatech.edu

2014-05-15

Purpose: Dual-energy CT (DECT) is being increasingly used for its capability of material decomposition and energy-selective imaging. A generic problem of DECT, however, is that the decomposition process is unstable in the sense that the relative magnitude of decomposed signals is reduced due to signal cancellation while the image noise is accumulating from the two CT images of independent scans. Direct image decomposition, therefore, leads to severe degradation of signal-to-noise ratio on the resultant images. Existing noise suppression techniques are typically implemented in DECT with the procedures of reconstruction and decomposition performed independently, which do not explore the statistical propertiesmore » of decomposed images during the reconstruction for noise reduction. In this work, the authors propose an iterative approach that combines the reconstruction and the signal decomposition procedures to minimize the DECT image noise without noticeable loss of resolution. Methods: The proposed algorithm is formulated as an optimization problem, which balances the data fidelity and total variation of decomposed images in one framework, and the decomposition step is carried out iteratively together with reconstruction. The noise in the CT images from the proposed algorithm becomes well correlated even though the noise of the raw projections is independent on the two CT scans. Due to this feature, the proposed algorithm avoids noise accumulation during the decomposition process. The authors evaluate the method performance on noise suppression and spatial resolution using phantom studies and compare the algorithm with conventional denoising approaches as well as combined iterative reconstruction methods with different forms of regularization. Results: On the Catphan©600 phantom, the proposed method outperforms the existing denoising methods on preserving spatial resolution at the same level of noise suppression, i.e., a reduction of noise standard deviation by one order of magnitude. This improvement is mainly attributed to the high noise correlation in the CT images reconstructed by the proposed algorithm. Iterative reconstruction using different regularization, including quadratic orq-generalized Gaussian Markov random field regularization, achieves similar noise suppression from high noise correlation. However, the proposed TV regularization obtains a better edge preserving performance. Studies of electron density measurement also show that our method reduces the average estimation error from 9.5% to 7.1%. On the anthropomorphic head phantom, the proposed method suppresses the noise standard deviation of the decomposed images by a factor of ∼14 without blurring the fine structures in the sinus area. Conclusions: The authors propose a practical method for DECT imaging reconstruction, which combines the image reconstruction and material decomposition into one optimization framework. Compared to the existing approaches, our method achieves a superior performance on DECT imaging with respect to decomposition accuracy, noise reduction, and spatial resolution.« less

Content Themes of Alcohol Advertising in U.S. Television-Latent Class Analysis.

PubMed

Morgenstern, Matthis; Schoeppe, Franziska; Campbell, Julie; Braam, Marloes W G; Stoolmiller, Michael; Sargent, James D

2015-09-01

There is little alcohol research that reports on the thematic contents of contemporary alcohol advertisements in U.S. television. Studies of alcohol ads from 2 decades ago did not identify "Partying" as a social theme. Aim of this study was to describe and classify alcohol advertisements aired in national television in terms of contents, airing times, and channel placements and to identify different marketing strategies of alcohol brands. Content analysis of all ads from the top 20 U.S. beer and spirit brands aired between July 2009 and June 2011. These were 581 unique alcohol ads accounting for 272,828 (78%) national television airings. Ads were coded according to predefined definitions of 13 content areas. A latent class analysis (LCA) was conducted to define content cluster themes and determine alcoholic brands that were more likely to exploit these themes. About half of the advertisements (46%) were aired between 3 am and 8 pm, and the majority were placed either in Entertainment (40%) and Sports (38%) channels. Beer ads comprised 64% of the sample, with significant variation in airing times and channels between types of products and brands. LCA revealed 5 content classes that exploited the "Partying," "Quality," "Sports," "Manly," and "Relax" themes. The partying class, indicative of ad messages surrounding partying, love, and sex, was the dominant theme comprising 42% of all advertisements. Ads for alcopops, flavored spirits, and liqueur were more likely to belong to the party class, but there were also some beer brands (Corona, Heineken) where more than 67% of ads exploited this theme. This is the first analysis to identify a partying theme to contemporary alcohol advertising. Future analyses can now determine whether exposure to that or other themes predicts alcohol misuse among youth audiences. Copyright © 2015 by the Research Society on Alcoholism.

Promoting calls to a quitline: quantifying the influence of message theme, strong negative emotions and graphic images in television advertisements.

PubMed

Farrelly, Matthew C; Davis, Kevin C; Nonnemaker, James M; Kamyab, Kian; Jackson, Christine

2011-07-01

To understand the relative effectiveness of television advertisements that differ in their thematic focus and portrayals of negative emotions and/or graphic images in promoting calls to a smokers' quitline. Regression analysis is used to explain variation in quarterly media market-level per smoker calls to the New York State Smokers' Quitline from 2001 to 2009. The primary independent variable is quarterly market-level delivery of television advertisements measured by target audience rating points (TARPs). Advertisements were characterised by their overall objective--promoting cessation, highlighting the dangers of secondhand smoke (SHS) or other--and by their portrayals of strong negative emotions and graphic images. Per smoker call volume is positively correlated with total TARPs (p<0.001), and cessation advertisements are more effective than SHS advertisements in promoting quitline call volume. Advertisements with graphic images only or neither strong negative emotions nor graphic images are associated with higher call volume with similar effect sizes. Call volume was not significantly associated with the number of TARPs for advertisements with strong negative emotions only (p=0.71) or with both graphic images and strong emotions (p=0.09). Exposure to television advertisements is strongly associated with quitline call volume, and both cessation and SHS advertisements can be effective. The use of strong negative emotions in advertisements may be effective in promoting smoking cessation in the population but does not appear to influence quitline call volume. Further research is needed to understand the role of negative emotions in promoting calls to quitlines and cessation more broadly among the majority of smokers who do not call quitlines.

Sparsity-based acoustic inversion in cross-sectional multiscale optoacoustic imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Yiyong; Tzoumas, Stratis; Nunes, Antonio

2015-09-15

Purpose: With recent advancement in hardware of optoacoustic imaging systems, highly detailed cross-sectional images may be acquired at a single laser shot, thus eliminating motion artifacts. Nonetheless, other sources of artifacts remain due to signal distortion or out-of-plane signals. The purpose of image reconstruction algorithms is to obtain the most accurate images from noisy, distorted projection data. Methods: In this paper, the authors use the model-based approach for acoustic inversion, combined with a sparsity-based inversion procedure. Specifically, a cost function is used that includes the L1 norm of the image in sparse representation and a total variation (TV) term. Themore » optimization problem is solved by a numerically efficient implementation of a nonlinear gradient descent algorithm. TV–L1 model-based inversion is tested in the cross section geometry for numerically generated data as well as for in vivo experimental data from an adult mouse. Results: In all cases, model-based TV–L1 inversion showed a better performance over the conventional Tikhonov regularization, TV inversion, and L1 inversion. In the numerical examples, the images reconstructed with TV–L1 inversion were quantitatively more similar to the originating images. In the experimental examples, TV–L1 inversion yielded sharper images and weaker streak artifact. Conclusions: The results herein show that TV–L1 inversion is capable of improving the quality of highly detailed, multiscale optoacoustic images obtained in vivo using cross-sectional imaging systems. As a result of its high fidelity, model-based TV–L1 inversion may be considered as the new standard for image reconstruction in cross-sectional imaging.« less

GPU-accelerated compressed-sensing (CS) image reconstruction in chest digital tomosynthesis (CDT) using CUDA programming

NASA Astrophysics Data System (ADS)

Choi, Sunghoon; Lee, Haenghwa; Lee, Donghoon; Choi, Seungyeon; Shin, Jungwook; Jang, Woojin; Seo, Chang-Woo; Kim, Hee-Joung

2017-03-01

A compressed-sensing (CS) technique has been rapidly applied in medical imaging field for retrieving volumetric data from highly under-sampled projections. Among many variant forms, CS technique based on a total-variation (TV) regularization strategy shows fairly reasonable results in cone-beam geometry. In this study, we implemented the TV-based CS image reconstruction strategy in our prototype chest digital tomosynthesis (CDT) R/F system. Due to the iterative nature of time consuming processes in solving a cost function, we took advantage of parallel computing using graphics processing units (GPU) by the compute unified device architecture (CUDA) programming to accelerate our algorithm. In order to compare the algorithmic performance of our proposed CS algorithm, conventional filtered back-projection (FBP) and simultaneous algebraic reconstruction technique (SART) reconstruction schemes were also studied. The results indicated that the CS produced better contrast-to-noise ratios (CNRs) in the physical phantom images (Teflon region-of-interest) by factors of 3.91 and 1.93 than FBP and SART images, respectively. The resulted human chest phantom images including lung nodules with different diameters also showed better visual appearance in the CS images. Our proposed GPU-accelerated CS reconstruction scheme could produce volumetric data up to 80 times than CPU programming. Total elapsed time for producing 50 coronal planes with 1024×1024 image matrix using 41 projection views were 216.74 seconds for proposed CS algorithms on our GPU programming, which could match the clinically feasible time ( 3 min). Consequently, our results demonstrated that the proposed CS method showed a potential of additional dose reduction in digital tomosynthesis with reasonable image quality in a fast time.

Depictions of substance use in reality television: a content analysis of The Osbournes.

PubMed

Blair, Nicole A; Yue, So Kuen; Singh, Ranbir; Bernhardt, Jay M

2005-12-24

To determine the source and slant of messages in a reality television programme that may promote or inhibit health related or risky behaviours. Coding visual and verbal references to alcohol, tobacco, and other drug (ATOD) use in The Osbournes. Three reviewers watched all 10 episodes of the first season and coded incidents of substance use according to the substance used (alcohol, tobacco, or drugs), the way use was portrayed (visually or verbally), the source of the message (the character in the show involved in the incident), and the slant of the incident (endorsement or rejection). The variation in number of messages in an average episode, the slant of messages, and message source. The average number of messages per episode was 9.1 (range 2-17). Most drug use messages (15, 54%) implied rejection of drugs, but most alcohol messages (30, 64%) and tobacco messages (12, 75%) implied endorsements for using these substances. Most rejections (34, 94%) were conveyed verbally, but most endorsements (36, 65%) were conveyed visually. Messages varied in frequency and slant by source. The reality television show analysed in this study contains numerous messages on substance use that imply both rejection and endorsement of use. The juxtaposition of verbal rejection messages and visual endorsement messages, and the depiction of contradictory messages about substance use from show characters, may send mixed messages to viewers about substance use.

Form cues and content difficulty as determinants of children's cognitive processing of televised educational messages.

PubMed

Campbell, T A; Wright, J C; Huston, A C

1987-06-01

An experiment was designed to assess the effects of formal production features and content difficulty on children's processing of televised messages about nutrition. Messages with identical content (the same script and visual shot sequence) were made in two forms: child program forms (animated film, second-person address, and character voice narration with sprightly music) and adult program forms (live photography, third-person address, and adult male narration with sedate background music). For each form, messages were made at three levels of content difficulty. Easier versions were longer, more redundant, and used simpler language; difficult versions presented information more quickly with less redundancy and more abstract language. Regardless of form or difficulty level, each set of bits presented the same basic information. Kindergarten children (N = 120) were assigned to view three different bits of the same form type and difficulty embedded in a miniprogram. Visual attention to child forms was significantly greater than to adult forms; free and cued recall scores were also higher for child than for adult forms. Although all recall and recognition scores were best for easy versions and worst for difficult versions, attention showed only minor variation as a function of content difficulty. Results are interpreted to indicate that formal production features, independently of content, influence the effort and level of processing that children use to understand televised educational messages.

Iterative Nonlocal Total Variation Regularization Method for Image Restoration

PubMed Central

Xu, Huanyu; Sun, Quansen; Luo, Nan; Cao, Guo; Xia, Deshen

2013-01-01

In this paper, a Bregman iteration based total variation image restoration algorithm is proposed. Based on the Bregman iteration, the algorithm splits the original total variation problem into sub-problems that are easy to solve. Moreover, non-local regularization is introduced into the proposed algorithm, and a method to choose the non-local filter parameter locally and adaptively is proposed. Experiment results show that the proposed algorithms outperform some other regularization methods. PMID:23776560

An l1-TV algorithm for deconvolution with salt and pepper noise

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlberg, Brendt; Rodriguez, Paul

2008-01-01

There has recently been considerable interest in applying Total Variation with an {ell}{sup 1} data fidelity term to the denoising of images subject to salt and pepper noise, but the extension of this formulation to more general problems, such as deconvolution, has received little attention, most probably because most efficient algorithms for {ell}{sup 1}-TV denoising can not handle more general inverse problems. We apply the Iteratively Reweighted Norm algorithm to this problem, and compare performance with an alternative algorithm based on the Mumford-Shah functional.

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

NASA Astrophysics Data System (ADS)

Aguilar, M.; Aisa, D.; Alpat, B.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bigongiari, G.; Bindi, V.; Bizzaglia, S.; Bizzarri, M.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Borsini, S.; Boschini, M. J.; Bourquin, M.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Cascioli, V.; Castellini, G.; Cernuda, I.; Cerreta, D.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, H.; Cheng, G. M.; Chen, H. S.; Cheng, L.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Gil, E. Cortina; Coste, B.; Creus, W.; Crispoltoni, M.; Cui, Z.; Dai, Y. M.; Delgado, C.; Della Torre, S.; Demirköz, M. B.; Derome, L.; Di Falco, S.; Di Masso, L.; Dimiccoli, F.; Díaz, C.; von Doetinchem, P.; Donnini, F.; Du, W. J.; Duranti, M.; D'Urso, D.; Eline, A.; Eppling, F. J.; Eronen, T.; Fan, Y. Y.; Farnesini, L.; Feng, J.; Fiandrini, E.; Fiasson, A.; Finch, E.; Fisher, P.; Galaktionov, Y.; Gallucci, G.; García, B.; García-López, R.; Gargiulo, C.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Gillard, W.; Giovacchini, F.; Goglov, P.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guandalini, C.; Guerri, I.; Guo, K. H.; Haas, D.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hoffman, J.; Hsieh, T. H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Kossakowski, R.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Levi, G.; Li, H. L.; Li, J. Q.; Li, Q.; Li, Q.; Li, T. X.; Li, W.; Li, Y.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, H.; Lolli, M.; Lomtadze, T.; Lu, M. J.; Lu, S. Q.; Lu, Y. S.; Luebelsmeyer, K.; Luo, J. Z.; Lv, S. S.; Majka, R.; Mañá, C.; Marín, J.; Martin, T.; Martínez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Müller, M.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Obermeier, A.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Papi, A.; Pauluzzi, M.; Pedreschi, E.; Pensotti, S.; Pereira, R.; Picot-Clemente, N.; Pilo, F.; Piluso, A.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Postaci, E.; Putze, A.; Quadrani, L.; Qi, X. M.; Qin, X.; Qu, Z. Y.; Räihä, T.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodríguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Sbarra, C.; Schael, S.; Schmidt, S. M.; von Dratzig, A. Schulz; Schwering, G.; Scolieri, G.; Seo, E. S.; Shan, B. S.; Shan, Y. H.; Shi, J. Y.; Shi, X. Y.; Shi, Y. M.; Siedenburg, T.; Son, D.; Spada, F.; Spinella, F.; Sun, W.; Sun, W. H.; Tacconi, M.; Tang, C. P.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Türkoǧlu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vaurynovich, S.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Vitale, V.; Vitillo, S.; Wang, L. Q.; Wang, N. H.; Wang, Q. L.; Wang, R. S.; Wang, X.; Wang, Z. X.; Weng, Z. L.; Whitman, K.; Wienkenhöver, J.; Wu, H.; Wu, X.; Xia, X.; Xie, M.; Xie, S.; Xiong, R. Q.; Xin, G. M.; Xu, N. S.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Ye, Q. H.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, J. H.; Zhang, M. T.; Zhang, X. B.; Zhang, Z.; Zheng, Z. M.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; Zurbach, C.; AMS Collaboration

2015-05-01

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.

Physical activity, obesity and cardiovascular diseases.

PubMed

Lakka, T A; Bouchard, C

2005-01-01

Sedentary lifestyle and overweight are major public health, clinical, and economical problems in modern societies. The worldwide epidemic of excess weight is due to imbalance between physical activity and dietary energy intake. Sedentary lifestyle, unhealthy diet, and consequent overweight and obesity markedly increase the risk of cardiovascular diseases. Regular physical activity 45-60 min per day prevents unhealthy weight gain and obesity, whereas sedentary behaviors such as watching television promote them. Regular exercise can markedly reduce body weight and fat mass without dietary caloric restriction in overweight individuals. An increase in total energy expenditure appears to be the most important determinant of successful exercise-induced weight loss. The best long-term results may be achieved when physical activity produces an energy expenditure of at least 2,500 kcal/week. Yet, the optimal approach in weight reduction programs appears to be a combination of regular physical activity and caloric restriction. A minimum of 60 min, but most likely 80-90 min of moderate-intensity physical activity per day may be needed to avoid or limit weight regain in formerly overweight or obese individuals. Regular moderate intensity physical activity, a healthy diet, and avoiding unhealthy weight gain are effective and safe ways to prevent and treat cardiovascular diseases and to reduce premature mortality in all population groups. Although the efforts to promote cardiovascular health concern the whole population, particular attention should be paid to individuals who are physically inactive, have unhealthy diets or are prone to weight gain. They have the highest risk for worsening of the cardiovascular risk factor profile and for cardiovascular disease. To combat the epidemic of overweight and to improve cardiovascular health at a population level, it is important to develop strategies to increase habitual physical activity and to prevent overweight and obesity in collaboration with communities, families, schools, work sites, health care professionals, media and policymakers.

Do Young People Ever Sit Still? Variations in Accelerometer Counts, Muscle Activity and Heart Rate across Various Sedentary Activities in Youth.

PubMed

van Ekris, Evi; Chinapaw, Mai J M; Rotteveel, Joost; Altenburg, Teatske M

2018-05-17

Evidence of adverse health effects of TV viewing is stronger than for overall sedentary behaviour in youth. One explanation may be that TV viewing involves less body movement than other sedentary activities. Variations in body movement across sedentary activities are currently unknown, as are age differences in such variations. This study examined body movement differences across various sedentary activities in children and adolescents, assessed by hip-, thigh- and wrist-worn accelerometers, muscle activity and heart rate. Body movement differences between sedentary activities and standing were also examined. Fifty-three children (aged 10⁻12 years) and 37 adolescents (aged 16⁻18 years) performed seven different sedentary activities, a standing activity, and a dancing activity (as a control activity) in a controlled setting. Each activity lasted 10 minutes. Participants wore an Actigraph on their hip and both wrists, an activPAL on their thigh and a heart rate monitor. The muscle activity of weight-bearing leg muscles was measured in a subgroup ( n = 38) by surface electromyography. Variations in body movement across activities were examined using general estimation equations analysis. Children showed significantly more body movement during sedentary activities and standing than adolescents. In both age groups, screen-based sedentary activities involved less body movement than non-screen-based sedentary activities. This may explain the stronger evidence for detrimental health effects of TV viewing while evidence for child sedentary behaviour in general is inconsistent. Differences in body movement during standing and sedentary activities were relatively small. Future research should examine the potential health effects of differences in body movement between screen-based versus non-screen based and standing versus sedentary activities.

Child and adolescent exposure to food and beverage brand appearances during prime-time television programming.

PubMed

Speers, Sarah E; Harris, Jennifer L; Schwartz, Marlene B

2011-09-01

The food industry disproportionately markets to young people through product placements. Children and adolescents may be more susceptible to these disguised persuasive attempts. Quantify incidence and youth exposure to food and beverage brand appearances within shows on prime-time TV. Data on the number of food, beverage, and restaurant brand appearances within shows during prime-time programming in 2008 were purchased from Nielsen and analyzed by product category and company in 2010. Exposure to these brand appearances by children, adolescents, and adults were examined and compared with exposure to prime-time TV advertisements for the same categories and companies using additional Nielsen data. Food, beverage, and restaurant brands appeared a total of 35,000 times within prime-time TV programming examined by Nielsen in 2008. Regular soft drinks, traditional restaurants (i.e., not quickserve), and energy/sports drinks made up 60% of all brand appearances. Young people viewed relatively few of these appearances with one notable exception. Coca-Cola products were seen 198 times by the average child and 269 times by the average adolescent during prime-time shows over the year, accounting for 70% of child exposure and 61% of adolescent exposure to brand appearances. One show, American Idol, accounted for more than 95% of these exposures. Exposure of children to Coca-Cola products through traditional advertisements was much less common. Brand appearances for most food industry companies, except for Coca-Cola, are relatively rare during prime-time programming with large youth audiences. Coca-Cola has pledged to refrain from advertising to children, yet the average child views almost four Coke appearances on prime-time TV every week. This analysis reveals a substantial, potential loophole in current food industry self-regulatory pledges to advertise only better-for-you foods to children. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Mothers' views of their preschool child's screen-viewing behaviour: a qualitative study.

PubMed

Bentley, Georgina F; Turner, Katrina M; Jago, Russell

2016-08-04

Research on screen-viewing in preschool children has predominantly focused on television viewing. The rapid development of mobile devices (e.g. tablets, smart phones and e-readers) and the increase in their use by preschool children means there is a need to understand how and why these devices are used by this age group. The aim of this study was to explore mothers' views of their preschool children's screen viewing behaviour (including mobile devices) and investigate how preschool children use different screen-viewing devices. One-to-one, semi-structured interviews with mothers of preschool children (aged between 2 and 4 years old). Mothers were recruited through preschools, nurseries, and mother and toddler groups located within four areas of varying socio-economic status within Bristol, UK. Data were analysed thematically using a framework approach. Twenty-six mothers were interviewed. Mobile devices were regularly used as a form of screen-viewing for most children but were used on an ad hoc basis rather than being a habitual activity. The reasons and influences of mobile device use described by mothers were similar to that of television viewing. However, the portability of mobile devices meant that they were often used outside of the home as a distraction tool. Their multi-functionality meant that they could be used as a portable television, or for purposeful learning through educational games and applications. Some mothers showed concerns over mobile device use by their child, whilst others felt it was an important and useful educational tool. Although the majority of mothers felt they needed to set rules and restrictions for mobile device use, many mothers felt that they are also a necessary and unavoidable part of life. Mothers in this study suggested that mobile device use by preschool children is common. More research is needed to determine the impact of mobile device use in preschool children, how much time preschool children spend using mobile devices and which activities their use may be replacing.

Teaching medicine with the help of "Dr. House".

PubMed

Jerrentrup, Andreas; Mueller, Tobias; Glowalla, Ulrich; Herder, Meike; Henrichs, Nadine; Neubauer, Andreas; Schaefer, Juergen R

2018-01-01

TV series such as "House MD", "Grey´s Anatomy" or "Emergency Room" are well perceived by medical students. Seminars featuring medical TV series such as "House MD" might serve as door-opener to attract medical students to learn more about rare diseases. The TV series "House MD" is troublesome for the main character Dr. House is an excellent diagnostician but at the same time a rather misanthropic person. Therefore, lecturing medicine with the help of "House MD" requires constant evaluation. From 2008 to 2016 we are using the well-known TV series "House MD" continuously to attract medical students and teach them about rare diseases as well as diagnostic strategies. We collected from 213 students a detailed questionnaire assessing their learning experience. 76.6% of our students (n = 157) reported to watching medical dramas on a regular basis. The Dr. House seminar was compared to traditional seminars and our students reported an improved learning effect (69.9%), better concentration (89.7%), higher motivation to participate (88.7%), and more fun (86.7%) (all p<0.001). The students see Dr. House's behavior quite critically. Likert assessment on a 5-point scale identified strong disagreement with Dr. House´s interpersonal skills in dealing with his colleagues (median = 1) and patients (median = 1). At the same time, the students strongly agreed with his outstanding diagnostic (median = 5) and therapeutic capabilities (median = 4). Medical students visiting a Dr. House teaching seminar are highly motivated to learn more about rare diseases. They were positively influenced by TV series such as Dr. House to improve their diagnostic and clinical skills. At the same time, they are critical enough not to see Dr. House as a role model for their own personality. Well performed medical TV shows such as Dr. House can successfully be used in an educational setting to motivate medical students to come into seminars to learn more about rare diseases.

Media, product differences and seasonality in alcohol advertising in 1997.

PubMed

Snyder, L B; Milici, F F; Mitchell, E W; Proctor, D C

2000-11-01

To spell out recent events related to the alcohol advertising controversy and to describe the extent of alcohol advertising for 1 year, the media favored for advertising different types of alcoholic beverages and seasonal variation in advertising patterns. Monthly advertising data for 1997 were obtained from a variety of sources, including a commercial media monitoring service, a watchdog group, and trade and business press. Media examined were national and local television, radio, magazines, newspapers and billboards. Alcohol advertising expenditures were greatest in the late spring/early summer and during the holiday season. Television received the preponderance of alcohol advertising dollars for beer, wine, wine coolers and premixed drinks. Distilled spirits relied mostly on magazine advertising. Beer was the most heavily advertised product. More than half of televised beer ads aired on Saturday or Sunday afternoon during sporting events. There were more radio and TV ads for premixed low-alcohol beverages--some of which contain distilled spirits and many using brand names of distilled spirits--than for higher proof distilled spirits. Public health officials can use the results to plan the month and media in which to launch messages against alcohol misuse, to directly counter pro-alcohol messages in advertising. They should monitor consumption and advertising of premixed beverages. Those concerned with the debate on alcohol advertising should note the access children have to beer ads when these ads are aired during weekend daytime sporting events, and that beer remains the greatest advertised beverage, despite the 1996 lifting of the broadcast advertising ban on distilled spirits.

Television, Home-Cooked Meals, and Family Meal Frequency: Associations with Adult Obesity.

PubMed

Tumin, Rachel; Anderson, Sarah E

2017-06-01

Adults, regardless of whether they are parents, regularly eat meals with family at home, but few studies have analyzed large, population-based samples to examine how mealtime practices or family meal frequency are associated with health. The aim of this study was to evaluate associations between the frequency of family meals eaten at home, watching television or videos during family meals, and consumption of meals that were cooked and eaten at home and the odds of being obese in adults. This was an analysis of the cross-sectional 2012 Ohio Medicaid Assessment Survey (OMAS), a telephone survey of Ohio's population. The study sample was adult Ohio residents responding to the 2012 OMAS who ate at least one family meal in the past week (n=12,842). Obesity (body mass index [BMI] ≥30), calculated from self-reported height and weight, was the outcome. Logistic regression models were used to examine the association between obesity and family meal practices, adjusted for respondents' employment status, marital status, race/ethnicity, educational attainment, and age. Family meal frequency was not associated with odds of obesity: those who ate family meals most (6-7) days were as likely as those who ate family meals few (1-2) days to be obese (adjusted odds ratio [OR adj ]=1.01, 95% CI=0.86, 1.18). Thirty-six percent of adults never watched television or videos while eating family meals, and 62% ate family meals that were all home-cooked. Adults who never watched television or videos during family meals had 37% lower odds of obesity compared with those who always did (95% CI=0.54, 0.73), regardless of family meal frequency. Adults whose family meals were all home-cooked had 26% lower odds of obesity than those who ate some or no home-cooked family meals (95% CI=0.62, 0.88). This association was more pronounced among adults who ate few family meals. Family meal practices may be associated with obesity in adults, even if they eat few family meals per week. Future research should examine more aspects of shared meals and investigate which specific practices may impact obesity risk. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Experimental investigation of passive thermodynamic vent system (TVS) with liquid nitrogen

NASA Astrophysics Data System (ADS)

Bae, Junhyuk; Yoo, Junghyun; Jin, Lingxue; Jeong, Sangkwon

2018-01-01

Thermodynamic vent system (TVS) is an attractive technology to maintain an allowable pressure level of a cryogenic propellant storage in a spacecraft under micro-gravity condition. There are two types of TVS; active or passive. In this paper, the passive TVS which does not utilize a cryogenic liquid circulation pump is experimentally investigated with liquid nitrogen and numerically analyzed by thermodynamic and heat transfer model. A cylindrical copper tank, which is 198 mm in inner diameter and 216 mm in height, is utilized to suppress a thermal-stratification effect of inside cryogenic fluid. A coil heat exchanger, which is 3 m in length and 6.35 mm in outer diameter, and a fixed size orifice of which diameter is 0.4 mm are fabricated to remove heat from the stored fluid to the vented flow. Each vent process is initiated at 140 kPa and ended at 120 kPa with liquid nitrogen fill levels which are 30%, 50% and 70%, respectively. In the numerical model, the fluid in the tank is assumed to be homogeneous saturated liquid-vapor. Mass and energy balance equations with heat transfer conditions suggested in this research are considered to calculate the transient pressure variation in the tank and the amount of heat transfer across the heat exchanger. We achieve the average heat rejection rate of more than 9 W by TVS and conclude that the passive TVS operates satisfactorily. In addition, the prediction model is verified by experimental results. Although the model has limitation in providing accurate results, it can surely predict the tendency of pressure and temperature changes in the tank. Furthermore, the model can suggest how we can improve the heat exchanger design to enhance an overall efficiency of passive TVS. Moreover, the performance of passive TVS is compared with other cryogenic vent systems (direct vent system and active TVS) by suggested performance indicator.

Dynamic re-weighted total variation technique and statistic Iterative reconstruction method for x-ray CT metal artifact reduction

NASA Astrophysics Data System (ADS)

Peng, Chengtao; Qiu, Bensheng; Zhang, Cheng; Ma, Changyu; Yuan, Gang; Li, Ming

2017-07-01

Over the years, the X-ray computed tomography (CT) has been successfully used in clinical diagnosis. However, when the body of the patient to be examined contains metal objects, the image reconstructed would be polluted by severe metal artifacts, which affect the doctor's diagnosis of disease. In this work, we proposed a dynamic re-weighted total variation (DRWTV) technique combined with the statistic iterative reconstruction (SIR) method to reduce the artifacts. The DRWTV method is based on the total variation (TV) and re-weighted total variation (RWTV) techniques, but it provides a sparser representation than TV and protects the tissue details better than RWTV. Besides, the DRWTV can suppress the artifacts and noise, and the SIR convergence speed is also accelerated. The performance of the algorithm is tested on both simulated phantom dataset and clinical dataset, which are the teeth phantom with two metal implants and the skull with three metal implants, respectively. The proposed algorithm (SIR-DRWTV) is compared with two traditional iterative algorithms, which are SIR and SIR constrained by RWTV regulation (SIR-RWTV). The results show that the proposed algorithm has the best performance in reducing metal artifacts and protecting tissue details.

Depth inpainting by tensor voting.

PubMed

Kulkarni, Mandar; Rajagopalan, Ambasamudram N

2013-06-01

Depth maps captured by range scanning devices or by using optical cameras often suffer from missing regions due to occlusions, reflectivity, limited scanning area, sensor imperfections, etc. In this paper, we propose a fast and reliable algorithm for depth map inpainting using the tensor voting (TV) framework. For less complex missing regions, local edge and depth information is utilized for synthesizing missing values. The depth variations are modeled by local planes using 3D TV, and missing values are estimated using plane equations. For large and complex missing regions, we collect and evaluate depth estimates from self-similar (training) datasets. We align the depth maps of the training set with the target (defective) depth map and evaluate the goodness of depth estimates among candidate values using 3D TV. We demonstrate the effectiveness of the proposed approaches on real as well as synthetic data.

Adversity, time, and well-being: A longitudinal analysis of time perspective in adulthood.

PubMed

Holman, E Alison; Silver, Roxane Cohen; Mogle, Jacqueline A; Scott, Stacey B

2016-09-01

Despite the prominence of time in influential aging theories and the ubiquity of stress across the life span, research addressing how time perspective (TP) and adversity are associated with well-being across adulthood is rare. Examining the role of TP in coping with life events over the life span would be best accomplished after large-scale population-based exposure to a specific event, with repeated assessments to examine within- and between-person differences over time. A national sample aged 18-91 years (N = 722, M = 49.4 years) was followed for 3 years after the September 11, 2001 (9/11) terrorist attacks. Respondents completed assessments of 9/11-related television (TV) exposure 9-21 days after the attacks, temporal disintegration 2 months post-9/11, and TP, ongoing stress, and well-being at 12, 24, and 36 months post-9/11. Results provided support for measurement invariance of TP across time and across age. Early 9/11-related TV exposure was significantly associated with greater temporal disintegration. Temporal disintegration and ongoing stress, in turn, were associated with between- and within-person variation in past TP. This effect was qualified by an age interaction that indicated a stronger relationship between ongoing stress and past TP for younger compared with older adults. Past and future TP were significantly and independently related to individual differences and within-person variation in psychological well-being, regardless of age. Future work should incorporate adversity as an important correlate of TP across adulthood. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Investigation into image quality difference between total variation and nonlinear sparsifying transform based compressed sensing

NASA Astrophysics Data System (ADS)

Dong, Jian; Kudo, Hiroyuki

2017-03-01

Compressed sensing (CS) is attracting growing concerns in sparse-view computed tomography (CT) image reconstruction. The most standard approach of CS is total variation (TV) minimization. However, images reconstructed by TV usually suffer from distortions, especially in reconstruction of practical CT images, in forms of patchy artifacts, improper serrate edges and loss of image textures. Most existing CS approaches including TV achieve image quality improvement by applying linear transforms to object image, but linear transforms usually fail to take discontinuities into account, such as edges and image textures, which is considered to be the key reason for image distortions. Actually, discussions on nonlinear filter based image processing has a long history, leading us to clarify that the nonlinear filters yield better results compared to linear filters in image processing task such as denoising. Median root prior was first utilized by Alenius as nonlinear transform in CT image reconstruction, with significant gains obtained. Subsequently, Zhang developed the application of nonlocal means-based CS. A fact is gradually becoming clear that the nonlinear transform based CS has superiority in improving image quality compared with the linear transform based CS. However, it has not been clearly concluded in any previous paper within the scope of our knowledge. In this work, we investigated the image quality differences between the conventional TV minimization and nonlinear sparsifying transform based CS, as well as image quality differences among different nonlinear sparisying transform based CSs in sparse-view CT image reconstruction. Additionally, we accelerated the implementation of nonlinear sparsifying transform based CS algorithm.

Trends in exposure to television food advertisements among children and adolescents in the United States.

PubMed

Powell, Lisa M; Szczypka, Glen; Chaloupka, Frank J

2010-09-01

To examine the trends in food advertising seen by American children and adolescents. Trend analysis of children's and adolescents' exposure to food advertising in 2003, 2005, and 2007, including separate analyses by race. Children aged 2 to 5 years and 6 to 11 years and adolescents aged 12 to 17 years. Television ratings. Exposure to total food advertising and advertising by food category. Between 2003 and 2007 daily average exposure to food ads fell by 13.7% and 3.7% among young children aged 2 to 5 and 6 to 11 years, respectively, but increased by 3.7% among adolescents aged 12 to 17 years. Exposure to sweets ads fell 41%, 29.3%, and 12.1%, respectively, for 2- to 5-, 6- to 11-, and 12- to 17-year-olds and beverage ads were down by about 27% to 30% across these age groups, with substantial decreases in exposure to ads for the most heavily advertised sugar-sweetened beverages-fruit drinks and regular soft drinks. Exposure to fast food ads increased by 4.7%, 12.2%, and 20.4% among children aged 2 to 5, 6 to 11, and 12 to 17 years, respectively, between 2003 and 2007. The racial gap in exposure to food advertising grew between 2003 and 2007, particularly for fast food ads. A number of positive changes have occurred in children's exposure to food advertising. Continued monitoring of food advertising exposure along with nutritional analyses is needed to further assess self-regulatory pledges.

An iterative shrinkage approach to total-variation image restoration.

PubMed

Michailovich, Oleg V

2011-05-01

The problem of restoration of digital images from their degraded measurements plays a central role in a multitude of practically important applications. A particularly challenging instance of this problem occurs in the case when the degradation phenomenon is modeled by an ill-conditioned operator. In such a situation, the presence of noise makes it impossible to recover a valuable approximation of the image of interest without using some a priori information about its properties. Such a priori information--commonly referred to as simply priors--is essential for image restoration, rendering it stable and robust to noise. Moreover, using the priors makes the recovered images exhibit some plausible features of their original counterpart. Particularly, if the original image is known to be a piecewise smooth function, one of the standard priors used in this case is defined by the Rudin-Osher-Fatemi model, which results in total variation (TV) based image restoration. The current arsenal of algorithms for TV-based image restoration is vast. In this present paper, a different approach to the solution of the problem is proposed based upon the method of iterative shrinkage (aka iterated thresholding). In the proposed method, the TV-based image restoration is performed through a recursive application of two simple procedures, viz. linear filtering and soft thresholding. Therefore, the method can be identified as belonging to the group of first-order algorithms which are efficient in dealing with images of relatively large sizes. Another valuable feature of the proposed method consists in its working directly with the TV functional, rather then with its smoothed versions. Moreover, the method provides a single solution for both isotropic and anisotropic definitions of the TV functional, thereby establishing a useful connection between the two formulae. Finally, a number of standard examples of image deblurring are demonstrated, in which the proposed method can provide restoration results of superior quality as compared to the case of sparse-wavelet deconvolution.

Improving thoracic four-dimensional cone-beam CT reconstruction with anatomical-adaptive image regularization (AAIR)

PubMed Central

Shieh, Chun-Chien; Kipritidis, John; O’Brien, Ricky T; Cooper, Benjamin J; Kuncic, Zdenka; Keall, Paul J

2015-01-01

Total-variation (TV) minimization reconstructions can significantly reduce noise and streaks in thoracic four-dimensional cone-beam computed tomography (4D CBCT) images compared to the Feldkamp-Davis-Kress (FDK) algorithm currently used in practice. TV minimization reconstructions are, however, prone to over-smoothing anatomical details and are also computationally inefficient. The aim of this study is to demonstrate a proof of concept that these disadvantages can be overcome by incorporating the general knowledge of the thoracic anatomy via anatomy segmentation into the reconstruction. The proposed method, referred as the anatomical-adaptive image regularization (AAIR) method, utilizes the adaptive-steepest-descent projection-onto-convex-sets (ASD-POCS) framework, but introduces an additional anatomy segmentation step in every iteration. The anatomy segmentation information is implemented in the reconstruction using a heuristic approach to adaptively suppress over-smoothing at anatomical structures of interest. The performance of AAIR depends on parameters describing the weighting of the anatomy segmentation prior and segmentation threshold values. A sensitivity study revealed that the reconstruction outcome is not sensitive to these parameters as long as they are chosen within a suitable range. AAIR was validated using a digital phantom and a patient scan, and was compared to FDK, ASD-POCS, and the prior image constrained compressed sensing (PICCS) method. For the phantom case, AAIR reconstruction was quantitatively shown to be the most accurate as indicated by the mean absolute difference and the structural similarity index. For the patient case, AAIR resulted in the highest signal-to-noise ratio (i.e. the lowest level of noise and streaking) and the highest contrast-to-noise ratios for the tumor and the bony anatomy (i.e. the best visibility of anatomical details). Overall, AAIR was much less prone to over-smoothing anatomical details compared to ASD-POCS, and did not suffer from residual noise/streaking and motion blur migrated from the prior image as in PICCS. AAIR was also found to be more computationally efficient than both ASD-POCS and PICCS, with a reduction in computation time of over 50% compared to ASD-POCS. The use of anatomy segmentation was, for the first time, demonstrated to significantly improve image quality and computational efficiency for thoracic 4D CBCT reconstruction. Further developments are required to facilitate AAIR for practical use. PMID:25565244

On convergence and convergence rates for Ivanov and Morozov regularization and application to some parameter identification problems in elliptic PDEs

NASA Astrophysics Data System (ADS)

Kaltenbacher, Barbara; Klassen, Andrej

2018-05-01

In this paper we provide a convergence analysis of some variational methods alternative to the classical Tikhonov regularization, namely Ivanov regularization (also called the method of quasi solutions) with some versions of the discrepancy principle for choosing the regularization parameter, and Morozov regularization (also called the method of the residuals). After motivating nonequivalence with Tikhonov regularization by means of an example, we prove well-definedness of the Ivanov and the Morozov method, convergence in the sense of regularization, as well as convergence rates under variational source conditions. Finally, we apply these results to some linear and nonlinear parameter identification problems in elliptic boundary value problems.

Magnitude of long-term non-lithostatic pressure variations in lithospheric processes: insight from thermo-mechanical subduction/collision models

NASA Astrophysics Data System (ADS)

Gerya, Taras

2014-05-01

On the one hand, the principle of lithostatic pressure is habitually used in metamorphic geology to calculate paleo-depths of metamorphism from mineralogical pressure estimates given by geobarometry. On the other hand, it is obvious that this lithostatic (hydrostatic) pressure principle should only be valid for an ideal case of negligible deviatoric stresses during the long-term development of the entire tectono-metamorphic system - the situation, which newer comes to existence in natural lithospheric processes. The question is therefore not "Do non-lithostatic pressure variations exist?" but " What is the magnitude of long-term non-lithostatic pressure variations in various lithospheric processes, which can be recorded by mineral equilibria of respective metamorphic rocks?". The later question is, in particular, relevant for various types of high-pressure (HP) and ultrahigh-pressure (UHP) rocks, which are often produced in convergent plate boundary settings (e.g., Hacker and Gerya, 2013). This question, can, in particular, be answered with the use of thermo-mechanical models of subduction/collision processes employing realistic P-T-stress-dependent visco-elasto-brittle/plastic rheology of rocks. These models suggest that magnitudes of pressure deviations from lithostatic values can range >50% underpressure to >100% overpressure, mainly in the regions of bending of rheologically strong mantle lithosphere (Burg and Gerya, 2005; Li et al., 2010). In particular, strong undepresures along normal faults forming within outer rise regions of subducting plates can be responsible for downward water suction and deep hydration of oceanic slabs (Faccenda et al., 2009). Weaker HP and UHP rocks of subduction/collision channels are typically subjected to lesser non-lithostatic pressure variations with characteristic magnitudes ranging within 10-20% from the lithostatic values (Burg and Gerya, 2005; Li et al., 2010). The strength of subducted crustal rocks and the degree of confinement of the subduction/collision channel are the key factors controlling this magnitude (Burg and Gerya, 2005; Li et al., 2010). High-temperature (>700 C) UHP rocks formed by continental crust subduction typically demonstrate negligible non-lithostatic pressure variations at peak metamorphic conditions, although these variations can be larger at the prograde stage (Gerya et al., 2008; Li et al., 2010). However, the variability of tectonic mechanisms by which UHP rocks can form (e.g., Sizova et al., 2012; Hacker and Gerya, 2013) precludes generalization of this result for all types of UHP-complexes. References Burg, J.-P., Gerya, T.V. (2005) Viscous heating and thermal doming in orogenic metamorphism: numerical modeling and geological implications. J. Metamorph. Geol., 23, 75-95. Faccenda, M., Gerya, T.V., Burlini, L. (2009) Deep slab hydration induced by bending related variations in tectonic pressure. Nature Geoscience, 2, 790-793. Gerya T.V., Perchuk, L.L., Burg J.-P. (2008) Transient hot channels: perpetrating and regurgitating ultrahigh-pressure, high temperature crust-mantle associations in collision belts. Lithos, 103, 236-256. Hacker, B., Gerya, T.V. (2013) Paradigms, new and old, for ultrahigh-pressure tectonism. Tectonophysics, 603, 79-88. Li, Z., Gerya, T.V., Burg, J.P. (2010) Influence of tectonic overpressure on P-T paths of HP-UHP rocks in continental collision zones: Thermomechanical modelling. J. Metamorphic Geol., 28, 227-247. Sizova, E., Gerya, T., Brown M. (2012) Exhumation mechanisms of melt-bearing ultrahigh pressure crustal rocks during collision of spontaneously moving plates. Journal of Metamorphic Geology, 30, 927-955.

Cultural variations in children's coping behaviour, TV viewing time, and family functioning.

PubMed

Chen, J-L; Kennedy, C

2005-09-01

To examine children's coping behaviour, TV viewing hours and family functioning in four ethnic groups and factors related to children's coping behaviour. This study was part of two larger research projects investigating children's health behaviours in the United States and Taiwan. Fifty-six White American children of European ancestry, 66 Mexican American children, 68 Chinese American children and 95 native Taiwanese children were included in the analysis. Standardized instruments were used to measure coping strategies, children's TV viewing hours and family functioning. There were significant differences in the types of stressor that children of different ethnicity reported. Similarities and differences were found in the four ethnic groups regarding the top five most frequently used and most effective coping strategies. Multiple regressions identified two variables that contributed significantly to the variance in the frequency of children's coping strategies--ethnicity and poorer behaviour control in the family. Ethnicity was the only variable found to contribute to the variance in coping effectiveness. Significant differences were found in the number of hours children spent watching TV. Findings suggest that children of different ethnicity utilized different types of coping strategies and ethnicity is one of the important factors related to children's coping behaviour. These findings provide evidence for nurses to assess children's coping behaviour and TV viewing and provide children with healthier alternatives.

The existence results and Tikhonov regularization method for generalized mixed variational inequalities in Banach spaces

NASA Astrophysics Data System (ADS)

Wang, Min

2017-06-01

This paper aims to establish the Tikhonov regularization method for generalized mixed variational inequalities in Banach spaces. For this purpose, we firstly prove a very general existence result for generalized mixed variational inequalities, provided that the mapping involved has the so-called mixed variational inequality property and satisfies a rather weak coercivity condition. Finally, we establish the Tikhonov regularization method for generalized mixed variational inequalities. Our findings extended the results for the generalized variational inequality problem (for short, GVIP( F, K)) in R^n spaces (He in Abstr Appl Anal, 2012) to the generalized mixed variational inequality problem (for short, GMVIP(F,φ , K)) in reflexive Banach spaces. On the other hand, we generalized the corresponding results for the generalized mixed variational inequality problem (for short, GMVIP(F,φ ,K)) in R^n spaces (Fu and He in J Sichuan Norm Univ (Nat Sci) 37:12-17, 2014) to reflexive Banach spaces.

Video noise reduction

NASA Astrophysics Data System (ADS)

Drewery, J. O.; Storey, R.; Tanton, N. E.

1984-07-01

A video noise and film grain reducer is described which is based on a first-order recursive temporal filter. Filtering of moving detail is avoided by inhibiting recursion in response to the amount of motion in a picture. Motion detection is based on the point-by-point power of the picture difference signal coupled with a knowledge of the noise statistics. A control system measures the noise power and adjusts the working point of the motion detector accordingly. A field trial of a manual version of the equipment at Television Center indicated that a worthwhile improvement in the quality of noisy or grainy pictures received by the viewer could be obtained. Subsequent trials of the automated version confirmed that the improvement could be maintained. Commercial equipment based on the design is being manufactured and marketed by Pye T.V.T. under license. It is in regular use on both the BBC1 and BBC2 networks.

Brain training in older adults: evidence of transfer to memory span performance and pseudo-Matthew effects.

PubMed

McDougall, Siné; House, Becky

2012-01-01

In this study the effects of 'brain training' using the Nintendo DS Brain Training program were examined in two groups of older adults; the cognitive performance of an experimental group (n = 21) who were asked to use the Nintendo DS regularly over a 6-week period was compared with the control group (n = 20). Groups were matched on age (mean age = 74 years), education, computer experience, daily activities (time spent reading or watching television), and initial scores of Wechsler Adult Intelligence Scale. Analyses revealed that improvements were primarily in the Digit Span Test, specifically Digits Backwards. Although the Brain Training package appeared to have some efficacy, other factors such as perceived quality of life and perceived cognitive functioning were at least equally important in determining training outcomes. The implications of these findings for cognitive training are discussed.

MIND--a five-state regional approach to continuing dental education.

PubMed

Watkins, F

1975-08-01

MIND has finished two years of operation as a regional center for continuing dental education. The responses from viewing cards, and the number of credit hours given, indicate that approximately 20% of the potential audience participated in the course offerings. Previous experience from a two-year study in South Dakota has shown that there are three major factors that are essential for effective use of television as a dissemination medium. These are as follows: 1) the program should establish effective use of the communication system to maintain an audience; 2) the quality of thr programming material that is televised must be high; 3) the program should be televised on a regular basis to develop viewer habits or expectations. With a potential audience of 11,000 persons, MIND has had to depend heavily on a bulk-rate mailing system to communicate with members of the dental profession. This has caused problems such as reminders not being received on time, or being lost in the mail, or not being read, so that the individual is unaware that the courses are being telecast. Another problem of mailing system is maintaining an up-to-date list of addresses. The names and addresses of the dental assistants are impossible to keep up to date. We use the lists of licensed dentists and dental hygienists issued each July and a list of the certified dental assistants, which, of course, does not include all the dental assistants in our five-state area. A system providing more direct contact with the individual needs to be developed. Quality of televised courses is determined by the clinician's style of presentation as well as by the content and organization of the course material. The selection of dental information aimed toward the dentist in general practice results in loss of some members of the viewing audience, particularly specialists and generalpractitioners who have confined their practice to a particular area of dentistry. Quality is also judged by the technical aspects such as camera coverage, color, types of audiovisual materials, and televison reception. There is a limited amount of videotaped material available, and the members of the Board of Directors are asked to preview the videotapes and select three courses that they judge to be of the best quality for the year's programs. One difficulty is to find courses that will be of value to all three groups--dentists, dental assistants, and dental hygienists. Despite the problems encountered, the use of educational television should focus on the positive characteristics of availability, relatively low cost of operation, and the opportunity to provide continuing dental education at a convenient time and place.

Switched Broadband Services For The Home

NASA Astrophysics Data System (ADS)

Sawyer, Don M.

1990-01-01

In considering the deployment of fiber optics to the residence, two critical questions arise: what are the leading services that could be offered to justify the required investment; and what is the nature of the business that would offer these services to the consumer ? This talk will address these two questions together with the related issue of how the "financial engine" of today's television distribution infrastructure - TV advertising - would be affected by an open access system based on fiber optics coupled with broadband switching. On the business side, the talk concludes that the potential for open ended capacity expansion, fair competition between service providers, and new interactive services inherent in an open access, switched broadband system are the critical items in differentiating it from existing video and TV distribution systems. On the question of broadband services, the talk will highlight several new opportunities together with some findings from recent market research conducted by BNR. The talk will show that there are variations on existing services plus many new services that could be offered and which have real consumer appeal. The postulated open access system discussed here is visualized as having ultimately 1,000 to 2,000 video channels available to the consumer. Although this may appear to hopelessly fragment the TV audience and destroy the current TV advertising infrastructure, the technology of open access, switched broadband will present many new advertising techniques, which have the potential to be far more effective than those available today. Some of these techniques will be described in this talk.

Playing active video games increases energy expenditure in children.

PubMed

Graf, Diana L; Pratt, Lauren V; Hester, Casey N; Short, Kevin R

2009-08-01

To compare energy expenditure rates in children playing the physically active video games, Dance Dance Revolution (DDR) and Nintendo's Wii Sports in relation to treadmill walking. Energy expenditure, heart rate, step rate, and perceived exertion were measured in 14 boys and 9 girls (ages 10-13 years; BMI at 3-98th percentile for age and gender) while watching television at rest, playing DDR at 2 skill levels, playing Wii bowling and boxing, and walking at 2.6, 4.2, and 5.7 km/h. Arterial elasticity was measured at rest and immediately after gaming. Compared with watching television, energy expenditure while gaming or walking increased 2- to 3-fold. Similarly, high rates of energy expenditure, heart rate, and perceived exertion were elicited from playing Wii boxing, DDR level 2, or walking at 5.7 km/h. This occurred despite variations in step rate among activities, reflecting greater use of upper body during Wii play (lowest step rate) than during walking (highest step rate) or DDR play. Wii bowling and beginner level DDR elicited a 2-fold increase in energy expenditure compared to television watching. Large-artery elasticity declined immediately after both DDR and Wii. The change was inversely related to the increment in energy expenditure above rest achieved during the activity. Energy expenditure during active video game play is comparable to moderate-intensity walking. Thus, for children who spend considerable time playing electronic screen games for entertainment, physically active games seem to be a safe, fun, and valuable means of promoting energy expenditure.

Depictions of substance use in reality television: a content analysis of The Osbournes

PubMed Central

Blair, Nicole A; Yue, So Kuen; Singh, Ranbir; Bernhardt, Jay M

2005-01-01

Objective To determine the source and slant of messages in a reality television programme that may promote or inhibit health related or risky behaviours. Design Coding visual and verbal references to alcohol, tobacco, and other drug (ATOD) use in The Osbournes. Review methods Three reviewers watched all 10 episodes of the first season and coded incidents of substance use according to the substance used (alcohol, tobacco, or drugs), the way use was portrayed (visually or verbally), the source of the message (the character in the show involved in the incident), and the slant of the incident (endorsement or rejection). Main outcome measures The variation in number of messages in an average episode, the slant of messages, and message source. Results The average number of messages per episode was 9.1 (range 2-17). Most drug use messages (15, 54%) implied rejection of drugs, but most alcohol messages (30, 64%) and tobacco messages (12, 75%) implied endorsements for using these substances. Most rejections (34, 94%) were conveyed verbally, but most endorsements (36, 65%) were conveyed visually. Messages varied in frequency and slant by source. Conclusions The reality television show analysed in this study contains numerous messages on substance use that imply both rejection and endorsement of use. The juxtaposition of verbal rejection messages and visual endorsement messages, and the depiction of contradictory messages about substance use from show characters, may send mixed messages to viewers about substance use. PMID:16373737

A sequential solution for anisotropic total variation image denoising with interval constraints

NASA Astrophysics Data System (ADS)

Xu, Jingyan; Noo, Frédéric

2017-09-01

We show that two problems involving the anisotropic total variation (TV) and interval constraints on the unknown variables admit, under some conditions, a simple sequential solution. Problem 1 is a constrained TV penalized image denoising problem; problem 2 is a constrained fused lasso signal approximator. The sequential solution entails finding first the solution to the unconstrained problem, and then applying a thresholding to satisfy the constraints. If the interval constraints are uniform, this sequential solution solves problem 1. If the interval constraints furthermore contain zero, the sequential solution solves problem 2. Here uniform interval constraints refer to all unknowns being constrained to the same interval. A typical example of application is image denoising in x-ray CT, where the image intensities are non-negative as they physically represent linear attenuation coefficient in the patient body. Our results are simple yet seem unknown; we establish them using the Karush-Kuhn-Tucker conditions for constrained convex optimization.

A compressed sensing based approach on Discrete Algebraic Reconstruction Technique.

PubMed

Demircan-Tureyen, Ezgi; Kamasak, Mustafa E

2015-01-01

Discrete tomography (DT) techniques are capable of computing better results, even using less number of projections than the continuous tomography techniques. Discrete Algebraic Reconstruction Technique (DART) is an iterative reconstruction method proposed to achieve this goal by exploiting a prior knowledge on the gray levels and assuming that the scanned object is composed from a few different densities. In this paper, DART method is combined with an initial total variation minimization (TvMin) phase to ensure a better initial guess and extended with a segmentation procedure in which the threshold values are estimated from a finite set of candidates to minimize both the projection error and the total variation (TV) simultaneously. The accuracy and the robustness of the algorithm is compared with the original DART by the simulation experiments which are done under (1) limited number of projections, (2) limited view problem and (3) noisy projections conditions.

Total Variation Denoising and Support Localization of the Gradient

NASA Astrophysics Data System (ADS)

Chambolle, A.; Duval, V.; Peyré, G.; Poon, C.

2016-10-01

This paper describes the geometrical properties of the solutions to the total variation denoising method. A folklore statement is that this method is able to restore sharp edges, but at the same time, might introduce some staircasing (i.e. “fake” edges) in flat areas. Quite surprisingly, put aside numerical evidences, almost no theoretical result are available to backup these claims. The first contribution of this paper is a precise mathematical definition of the “extended support” (associated to the noise-free image) of TV denoising. This is intuitively the region which is unstable and will suffer from the staircasing effect. Our main result shows that the TV denoising method indeed restores a piece-wise constant image outside a small tube surrounding the extended support. Furthermore, the radius of this tube shrinks toward zero as the noise level vanishes and in some cases, an upper bound on the convergence rate is given.

Unsafe and violent behavior in commercials aired during televised major sporting events.

PubMed

Tamburro, Robert F; Gordon, Patricia L; D'Apolito, James P; Howard, Scott C

2004-12-01

Injuries are the leading cause of death in children, and media exposure seems to increase children's risk-taking behavior. Televised sports are commonly viewed by children. The objective of this study was to determine the proportion of commercials that depict violence or other unsafe behavior during major televised sporting events that are aired before 9:00 pm. We obtained a list of the 50 sports programs that were most highly rated by Nielsen Media Research and that were televised between September 1, 2001, and September 1, 2002. These 50 programs included Winter Olympics events (n = 15), National Football League (NFL) regular season games (n = 14), NFL playoff games (n = 10), Major League Baseball World Series and playoff games (n = 7), the NFL Super Bowl (n = 1), the National Basketball Association Western Conference Final Game (n = 1), the College Football Rose Bowl (n = 1), and the National Collegiate Athletic Association Basketball Championship game (n = 1). Two other events were reviewed as well: the final round of the Masters Golf Championship, because it was the only sporting event rated in the top 50 of the previous year that was not represented by a similar sporting event in the study year, and the Daytona 500 National Association for Stock Car Auto Racing race, because it was the only event rated among the top 75 of the study year that was not represented by a similar event (ie, there were no other golfing or auto racing events reviewed). These events were included because different sporting events may attract different viewers and different advertisements; thus, their inclusion provides a more comprehensive evaluation of the topic. For sporting events with >3 programs in the top 50 (NFL regular season games, NFL playoff games, Winter Olympic events, and Major League Baseball World Series), representative samples of events were assessed. Surrogate events were analyzed for programs that were aired after 9:00 PM (Eastern Time) to control for the reduced likelihood of viewing by children after 9:00 PM. For example, afternoon telecasts of the National Collegiate Athletic Association Regional Final and National Semifinal games were assessed in place of the Championship game, which started after 9:00 PM. Weekend afternoon telecasts of the Winter Olympics (3 successive weekends) were assessed as surrogates for all Olympics telecasts. For the World Series, the Super Bowl, and the National Basketball Association Conference Championship games, which began before 9:00 PM but ended after that time, we evaluated only commercials that aired before 9:00 PM. All commercials that were aired during these programs were reviewed at standard speed for unsafe behavior or violence. Commercials that were aired during pregame, postgame, or halftime periods were not assessed. Commercials were categorized according to the product being advertised. Unsafe behavior was simply defined as any action that could have harmful consequences or that contravened the injury prevention recommendations of national organizations. Violence was defined as any intentional physical contact by an aggressor that had the potential to inflict injury or harm or the legitimate threat of such action. All commercials were reviewed by at least 2 investigators; when the 2 could not agree on the findings, a third investigator was used to resolve differences. The percentage of commercials and of commercial breaks that portrayed violent or unsafe behavior was determined for each category of event and advertised product. A commercial break was defined as a series of commercials shown during a single break from the sporting event. chi2 analysis was used for all analyses, and relative risks with 95% confidence intervals were determined. The proportion of commercials that depicted unsafe behavior and/or violence during each sporting event was compared with the proportion of such commercials that were observed during the Masters Golf Tournament (which had the lowest proportion of commercials depicting such behavior). The proportion of commercials that contained violent/unsafe behavior for each advertised product was compared with the proportion of such commercials that advertised food or nonalcoholic beverages. Food and nonalcoholic beverage commercials were selected as the reference because they are a well-defined, common category of commercial. Of the 1185 commercials assessed, 14% (n = 165) displayed unsafe behavior and 6% (n = 66) depicted violence. Of the 322 commercial breaks, 158 (49%) contained at least 1 commercial showing unsafe behavior or violence. Sixty-three commercials required review by a third investigator to adjudicate violence or unsafe behavior; 20 of 52 were ultimately judged to portray unsafe behavior, and 4 of 11 were ultimately judged to portray violence. Sporting events differed in the proportion of commercials that showed violence or unsafe behavior. The Super Bowl had the highest proportion of such commercials, and the Masters Golf Tournament had the least (relative risk: 4.3; 95% confidence interval: 1.4-12.5). The Masters Golf Tournament was noteworthy for the complete absence of violent commercials. Only 18% of reviewed commercials advertised movies or television programs, yet these commercials accounted for 86% of all violent commercials. Forty-eight percent of commercials that contained violence were for movies, and an additional 38% were for television programs. Nearly two thirds of all commercials for movies contained violence, whereas 15% of all commercials for television programs contained violence, a rate that increased to 22% when commercials for other sporting events were excluded. Several categories of commercials portrayed unsafe behaviors; commercials for automobiles accounted for the most. In 8 different categories, 10% or more of the commercials depicted unsafe behavior, and 7 were significantly more likely to depict such behavior than a food or beverage commercial. Children who watch televised sports view a significant amount of violent and unsafe behavior. In accordance with American Academy of Pediatrics recommendations for television viewing, parents should both limit and directly supervise children's viewing of these events. Our findings suggest that parents should remain present during commercials or should consider implementing commercial-skipping technology. In addition, efforts should be made to regulate the content of commercials that promote television programs and movies on the basis of the hour at which the sporting event is aired. Moreover, the sports, movie, and television industries should be encouraged to adopt models of advertising that limit or eliminate such content. These efforts could help to ensure that the viewing of televised sporting events is a safe and positive experience for children.

TH-AB-BRA-02: Automated Triplet Beam Orientation Optimization for MRI-Guided Co-60 Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, D; Thomas, D; Cao, M

2016-06-15

Purpose: MRI guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target tracking and adaptive radiotherapy. To remedy the low output limitation, the system uses three Co-60 sources at 120° apart, but using all three sources in planning is considerably unintuitive. We automate the beam orientation optimization using column generation, and then solve a novel fluence map optimization (FMO) problem while regularizing the number of MLC segments. Methods: Three patients—1 prostate (PRT), 1 lung (LNG), and 1 head-and-neck boost plan (H&NBoost)—were evaluated. The beamlet dose for 180 equally spaced coplanar beams under 0.35 T magnetic field wasmore » calculated using Monte Carlo. The 60 triplets were selected utilizing the column generation algorithm. The FMO problem was formulated using an L2-norm minimization with anisotropic total variation (TV) regularization term, which allows for control over the number of MLC segments. Our Fluence Regularized and Optimized Selection of Triplets (FROST) plans were compared against the clinical treatment plans (CLN) produced by an experienced dosimetrist. Results: The mean PTV D95, D98, and D99 differ by −0.02%, +0.12%, and +0.44% of the prescription dose between planning methods, showing same PTV dose coverage. The mean PTV homogeneity (D95/D5) was at 0.9360 (FROST) and 0.9356 (CLN). R50 decreased by 0.07 with FROST. On average, FROST reduced Dmax and Dmean of OARs by 6.56% and 5.86% of the prescription dose. The manual CLN planning required iterative trial and error runs which is very time consuming, while FROST required minimal human intervention. Conclusions: MRI guided Co-60 therapy needs the output of all sources yet suffers from unintuitive and laborious manual beam selection processes. Automated triplet orientation optimization is shown essential to overcome the difficulty and improves the dosimetry. A novel FMO with regularization provides additional controls over the number of MLC segments and treatment time. Varian Medical Systems; NIH grant R01CA188300; NIH grant R43CA183390.« less

Surface features on Mars: Ground-based albedo and radar compared with Mariner 9 topography

NASA Technical Reports Server (NTRS)

Frey, H.

1973-01-01

Earth-based albedo maps of Mars were compared with Mariner 9 television data and ground-based radar profiles to investigate the nature of the bright and dark albedo features. Little correlation was found except at the boundaries of classical albedo features, where some topographic control is indicated. Wind-blown dust models for seasonal and secular albedo variations are supported, but it is not clear whether the fines are derived from bright or dark parent rock. Mars, like the Earth and Moon, has probably generated two distinct types of crustal material.

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station.

PubMed

Aguilar, M; Aisa, D; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cerreta, D; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Cortina Gil, E; Coste, B; Creus, W; Crispoltoni, M; Cui, Z; Dai, Y M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Donnini, F; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gargiulo, C; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Haas, D; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Levi, G; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lolli, M; Lomtadze, T; Lu, M J; Lu, S Q; Lu, Y S; Luebelsmeyer, K; Luo, J Z; Lv, S S; Majka, R; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pauluzzi, M; Pedreschi, E; Pensotti, S; Pereira, R; Picot-Clemente, N; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Qin, X; Qu, Z Y; Räihä, T; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Vitale, V; Vitillo, S; Wang, L Q; Wang, N H; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Wu, X; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

2015-05-01

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.

Apollo experience report: Command and service module communications subsystem

NASA Technical Reports Server (NTRS)

Lattier, E. E., Jr.

1974-01-01

The development of spacecraft communications hardware from design to operation is described. Programs, requirements, specifications, and design approaches for a variety of functions (such as voice, telemetry, television, and antennas) are reviewed. Equipment environmental problems such as vibration, extreme temperature variation, and zero gravity are discussed. A review of the development of managerial techniques used in refining the roles of prime and subcontractors is included. The hardware test program is described in detail as it progressed from breadboard design to manned flight system evaluations. Finally, a series of actions is recommended to managers of similar projects to facilitate administration.

A feature refinement approach for statistical interior CT reconstruction

NASA Astrophysics Data System (ADS)

Hu, Zhanli; Zhang, Yunwan; Liu, Jianbo; Ma, Jianhua; Zheng, Hairong; Liang, Dong

2016-07-01

Interior tomography is clinically desired to reduce the radiation dose rendered to patients. In this work, a new statistical interior tomography approach for computed tomography is proposed. The developed design focuses on taking into account the statistical nature of local projection data and recovering fine structures which are lost in the conventional total-variation (TV)—minimization reconstruction. The proposed method falls within the compressed sensing framework of TV minimization, which only assumes that the interior ROI is piecewise constant or polynomial and does not need any additional prior knowledge. To integrate the statistical distribution property of projection data, the objective function is built under the criteria of penalized weighed least-square (PWLS-TV). In the implementation of the proposed method, the interior projection extrapolation based FBP reconstruction is first used as the initial guess to mitigate truncation artifacts and also provide an extended field-of-view. Moreover, an interior feature refinement step, as an important processing operation is performed after each iteration of PWLS-TV to recover the desired structure information which is lost during the TV minimization. Here, a feature descriptor is specifically designed and employed to distinguish structure from noise and noise-like artifacts. A modified steepest descent algorithm is adopted to minimize the associated objective function. The proposed method is applied to both digital phantom and in vivo Micro-CT datasets, and compared to FBP, ART-TV and PWLS-TV. The reconstruction results demonstrate that the proposed method performs better than other conventional methods in suppressing noise, reducing truncated and streak artifacts, and preserving features. The proposed approach demonstrates its potential usefulness for feature preservation of interior tomography under truncated projection measurements.

A feature refinement approach for statistical interior CT reconstruction.

PubMed

Hu, Zhanli; Zhang, Yunwan; Liu, Jianbo; Ma, Jianhua; Zheng, Hairong; Liang, Dong

2016-07-21

Interior tomography is clinically desired to reduce the radiation dose rendered to patients. In this work, a new statistical interior tomography approach for computed tomography is proposed. The developed design focuses on taking into account the statistical nature of local projection data and recovering fine structures which are lost in the conventional total-variation (TV)-minimization reconstruction. The proposed method falls within the compressed sensing framework of TV minimization, which only assumes that the interior ROI is piecewise constant or polynomial and does not need any additional prior knowledge. To integrate the statistical distribution property of projection data, the objective function is built under the criteria of penalized weighed least-square (PWLS-TV). In the implementation of the proposed method, the interior projection extrapolation based FBP reconstruction is first used as the initial guess to mitigate truncation artifacts and also provide an extended field-of-view. Moreover, an interior feature refinement step, as an important processing operation is performed after each iteration of PWLS-TV to recover the desired structure information which is lost during the TV minimization. Here, a feature descriptor is specifically designed and employed to distinguish structure from noise and noise-like artifacts. A modified steepest descent algorithm is adopted to minimize the associated objective function. The proposed method is applied to both digital phantom and in vivo Micro-CT datasets, and compared to FBP, ART-TV and PWLS-TV. The reconstruction results demonstrate that the proposed method performs better than other conventional methods in suppressing noise, reducing truncated and streak artifacts, and preserving features. The proposed approach demonstrates its potential usefulness for feature preservation of interior tomography under truncated projection measurements.

Separated Component-Based Restoration of Speckled SAR Images

DTIC Science & Technology

2014-01-01

One of the simplest approaches for speckle noise reduction is known as multi-look processing. It involves non-coherently summing the independent...image is assumed to be piecewise smooth [21], [22], [23]. It has been shown that TV regular- ization often yields images with the stair -casing effect...as a function f , is to be decomposed into a sum of two components f = u+ v, where u represents the cartoon or geometric (i.e. piecewise smooth

Targeting SRC Family Kinases and HSP90 in Lung Cancer

DTIC Science & Technology

2016-12-01

inhalation of Adeno-Cre, followed by MRI imaging at regular intervals to detect tumor initiation and growth, followed by euthanasia and processing of...experimental endpoint. 10 mice were used per time point Representative MRI data describing tumor volume (TV) are shown in Figure 1. Quantification of data is...dasatinib, we were able to make several conclusions. Figure 1. Representative MRI images from Nedd9wt or Nedd9 null Kras mutant mice, treated with

Do trends in physical activity, sedentary, and dietary behaviors support trends in obesity prevalence in 2 border regions in Texas?

PubMed

Ezendam, Nicole P M; Springer, Andrew E; Brug, Johannes; Oenema, Anke; Hoelscher, Deanna H

2011-01-01

The aim of the study was to compare the change in energy balance-related behaviors from 2000-2002 to 2004-2005 between 2 Texas regions with distinct patterns in obesity prevalence (decrease in the El Paso region [EP] and leveling off in the Rio Grande Valley region [RGV]) and to determine the role of the behaviors in the difference in obesity prevalence between the regions. Cross-sectional measurements of the School Physical Activity and Nutrition Study. Elementary schools. 3,949 children (9-10 years). Body mass index (objectively measured) and behaviors (self-assessed). Probability and post-stratification weighting procedures and mediation analysis. Compared to students in the RGV, students in the EP experienced a smaller decrease in sports team participation, an increase in regular meal consumption, and an increase in the frequency of milk/yogurt, cereal, sweet snacks, and frozen dessert consumption between measurement periods. Prevalence of frequent television viewing was lower in the EP. The lower body mass index in the EP was associated with regular meal consumption, and higher milk/yogurt and sweet snack consumption. Improvement of physical activity, sedentary behaviors, and healthful diet, but not unhealthful diet like sweet snack consumption, seem to be related to the decrease in obesity in the EP. Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

Inhibition coefficient and molecular diversity of multi stress tolerant Trichoderma as potential biocontrol agent against Sclerotium rolfsii Sacc.

PubMed

Hirpara, Darshna G; Gajera, H P; Hirapara, Jaydeep G; Golakiya, B A

2017-11-01

Trichoderma is one of the most exploited biocontrol agent for the management of plant diseases. Twenty strains of Trichoderma (six of T. harzianum, four of T. viride, three of T. virens, three of T. koningii, each one of T. hamatum, T. reesei, T. parceramosum and Trichoderma spp.) subjected to in vitro antagonism up to 12days after inoculation against Sclerotium rolfsii Sacc. causing stem rot in groundnut. A new concept was developed to determine inhibition coefficient representing pathogen biology and biocontrol related biophysical variables. Results explained differential inhibition coefficient of test pathogen by Trichoderma antagonists. The inhibition coefficient of test pathogen was examined highest (91.13%) by T. virens NBAII Tvs12 followed by T. virens MTCC 794 (89.33%) and T. koningii MTCC 796 (62.39%). Microscopic study confirmed biocontrol mechanism as mycoparasitism for Tvs12 and antibiosis for T. koningii MTCC 796. The sclerotial biogenesis of test pathogen was elevated during weak antagonism and diminished in interactions with strong antagonists. The inhibition coefficient of S. rolfsii was significantly negatively correlated with sclerotia formation and lipid peroxidation during the antagonism. Trichoderma strains were screened for fungicides (carbendazim and tebuconazole, thiram and mancozeb) and abiotic stress (drought and salt) tolerance. Results indicated that T. koningii MTCC 796 efficiently grew better than the other strains with maximum radial growth under adverse conditions. The genetic variability among the Trichoderma was determined using 34 gene specific markers which amplified 146 alleles. The SSR similarities explained substantial diversity (15 to 87%) across Trichoderma strains and pathogen S. rolfsii. Principal coordinates analysis (PCA) were comparable to the cluster analysis and first three most informative PC components explained 64.45% of the total variation. In PCA, potent antagonists appear to be distinct from other strains. Five SSR markers T1F/T1R (311) , TvCTT56f/TvCTT56r (387) , TvGAT18f/TvGAT18r (364) , TvCA39f/TvCA39r (196) and TvAG29f/TvAG29r (418) found to be unique to distinguish best antagonist strain Tvs12. However, MTCC 796 was examined most stress tolerant strain with better inhibition coefficient which might be useful to control the disease under adverse conditions or as a part of integrated pest management. Copyright © 2017. Published by Elsevier B.V.

Imran Khan and EPI: challenging conventional approaches to health promotion in Pakistan.

PubMed

Stiles, M

1995-01-01

In Pakistan, international donors and the Ministry of Health produced tens of thousands of posters and calendars featuring a national sports hero who promoted immunization on television at an exorbitant cost to USAID. After field testing the spots on 120 rural mothers with children under the age of 5, it turned out that 72% of them did not recognize the cricket champion. This meant that the conventional thinking of donors about effective health promotion had to be challenged. A nationwide media survey also confirmed this opinion indicating that in rural households only 18% watched TV regularly, only 14% listened to radio regularly, and only 2% read newspapers. They received the best advice on child health from doctors, paramedics, and family members. The Canadian International Development Agency (CIDA) used these findings to signal a change in policy and put greater emphasis on interpersonal communication. The typical vaccination course held for field worker vaccinators was regimented and unimaginative. Therefore, a 3-day workshop was designed consisting of interactive exercises and role plays on interpersonal communication and motivation; and on some key technical aspects of immunization and diarrheal disease control. Pilot training sessions were held in all four provinces; a curriculum was devised and a colorful trainer's guide was produced. More than 270 master trainers were trained in the provinces, some of whom eventually trained more than 10,000 vaccinators. In health communication interaction (two-way exchanges of information) that induces people to adopt health-enhancing behaviors was emphasized. Designing the right messages had to do with listening, analysis, persuasion, and story-telling for effective communication. More decentralization was also attempted, but resistance was encountered from the bureaucracy who could not be convinced that health promotion was the task of everyone in the field not just the prerogative of health educators working in the provincial health department. The training materials were later used in Bangladesh and Africa.

Content Themes of Alcohol Advertising in US Television — Latent Class Analysis

PubMed Central

Morgenstern, Matthis; Schoeppe, Franziska; Campbell, Julie; Braam, Marloes W.G.; Stoolmiller, Michael; Sargent, James D.

2015-01-01

Background There is little alcohol research that reports on the thematic contents of contemporary alcohol advertisements in US television. Studies of alcohol ads from two decades ago did not identify “partying” as a social theme. Aim of the present study was to describe and classify alcohol advertisements aired in national television in terms of contents, airing times, and channel placements and to identify different marketing strategies of alcohol brands. Methods Content analysis of all ads from the top 20 US beer and spirit brands aired between July 2009 and June 2011. These were 581 unique alcohol ads accounting for 272,828 (78%) national television airings. Ads were coded according to predefined definitions of 13 content areas. A latent class analysis (LCA) was conducted to define content cluster themes and determine alcoholic brands that were more likely to exploit these themes. Results About half of the advertisements (46%) were aired between 3am and 8pm, and the majority were placed either in Entertainment (40%) and Sports (38%) channels. Beer ads comprised 64% of the sample, with significant variation in airing times and channels between types of products and brands. LCA revealed five content classes that exploited the “Partying”, “Quality”, “Sports”, “Manly”, and “Relax” themes. The partying class, indicative of ad messages surrounding partying, love and sex, was the dominant theme, comprising 42% of all advertisements. Ads for alcopops, flavored spirits, and liqueur were more likely to belong to the party class, but there were also some beer brands (Corona, Heineken) where more than 67% of ads exploited this theme. Conclusions This is the first analysis to identify a partying theme to contemporary alcohol advertising. Future analyses can now determine whether exposure to that or other themes predicts alcohol misuse among youth audiences. PMID:26207317

Personalized Web-Based Advice in Combination With Well-Child Visits to Prevent Overweight in Young Children: Cluster Randomized Controlled Trial

PubMed Central

van Grieken, Amy; Vlasblom, Eline; Wang, Lu; Beltman, Maaike; Boere-Boonekamp, Magda M; L'Hoir, Monique P

2017-01-01

Background Overweight is a major health issue, and parent-targeted interventions to promote healthy development in children are needed. Objective The study aimed to evaluate E-health4Uth Healthy Toddler, an intervention that educates parents of children aged 18 to 24 months regarding health-related behaviors, as compared with usual care. The effect of this intervention on the following primary outcomes was evaluated when the children were 36 months of age: health-related behaviors (breakfast daily, activity and outside play, sweetened beverage consumption, television (TV) viewing and computer time), body mass index (BMI), and the prevalence of overweight and obesity. Methods The BeeBOFT (acronym for breastfeeding, breakfast daily, outside playing, few sweet drinks, less TV viewing) study is a cluster randomized controlled trial involving 51 Youth Health Care (YHC) teams. In total, 1094 parents participated in the control group, and 1008 parents participated in the E-health4Uth Healthy Toddler intervention group. The intervention consisted of Web-based personalized advice given to parents who completed an eHealth module and discussion of the advice during a regular well-child visit. In this study the eHealth module was offered to parents before two regular well-child visits at 18 and 24 months of age. During the well-child visits, the parents’ personalized advice was combined with face-to-face counseling provided by the YHC professional. Parents in the control group received usual care, consisting of the regular well-child visits during which general information on child health-related behavior was provided to parents. Parents completed questionnaires regarding family characteristics and health-related behaviors when the child was 1 month (inclusion), 6 months, 14 months, and 36 months (follow-up) of age. The child’s height and weight were measured by trained health care professionals from birth through 36 months of age at fixed time points. Multilevel linear and logistic regression models were used to evaluate the primary outcomes at 36 months of age. Results At 36 months, we observed no differences between health-related behaviors of children, BMI or the percentage of children having overweight or obesity in the control and intervention group (P>.05). An analysis of the intervention effect revealed that boys benefited from eating breakfast daily, non-Dutch children spent more time being active or playing outdoors, children of low-educated parents and of overweight and obese mothers spent less time watching TV or using the computer, and children of normal weight mothers drank less sweetened beverages (P<.05) compared with the control group. Conclusions The E-health4Uth Healthy Toddler intervention resulted in small improvements in health-related behaviors among subgroups but had no significant effects with respect to the children’s BMI. We conclude that the E-health4Uth Healthy Toddler intervention may be useful for pediatric health care professionals in terms of providing parents with personalized information regarding their child’s health-related behaviors. Trial Registration Netherlands Trial Register: NTR1831; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1831 (Archived by WebCite at http://www.webcitation.org/6mm5YFOB0) PMID:28751299

Personalized Web-Based Advice in Combination With Well-Child Visits to Prevent Overweight in Young Children: Cluster Randomized Controlled Trial.

PubMed

van Grieken, Amy; Vlasblom, Eline; Wang, Lu; Beltman, Maaike; Boere-Boonekamp, Magda M; L'Hoir, Monique P; Raat, Hein

2017-07-27

Overweight is a major health issue, and parent-targeted interventions to promote healthy development in children are needed. The study aimed to evaluate E-health4Uth Healthy Toddler, an intervention that educates parents of children aged 18 to 24 months regarding health-related behaviors, as compared with usual care. The effect of this intervention on the following primary outcomes was evaluated when the children were 36 months of age: health-related behaviors (breakfast daily, activity and outside play, sweetened beverage consumption, television (TV) viewing and computer time), body mass index (BMI), and the prevalence of overweight and obesity. The BeeBOFT (acronym for breastfeeding, breakfast daily, outside playing, few sweet drinks, less TV viewing) study is a cluster randomized controlled trial involving 51 Youth Health Care (YHC) teams. In total, 1094 parents participated in the control group, and 1008 parents participated in the E-health4Uth Healthy Toddler intervention group. The intervention consisted of Web-based personalized advice given to parents who completed an eHealth module and discussion of the advice during a regular well-child visit. In this study the eHealth module was offered to parents before two regular well-child visits at 18 and 24 months of age. During the well-child visits, the parents' personalized advice was combined with face-to-face counseling provided by the YHC professional. Parents in the control group received usual care, consisting of the regular well-child visits during which general information on child health-related behavior was provided to parents. Parents completed questionnaires regarding family characteristics and health-related behaviors when the child was 1 month (inclusion), 6 months, 14 months, and 36 months (follow-up) of age. The child's height and weight were measured by trained health care professionals from birth through 36 months of age at fixed time points. Multilevel linear and logistic regression models were used to evaluate the primary outcomes at 36 months of age. At 36 months, we observed no differences between health-related behaviors of children, BMI or the percentage of children having overweight or obesity in the control and intervention group (P>.05). An analysis of the intervention effect revealed that boys benefited from eating breakfast daily, non-Dutch children spent more time being active or playing outdoors, children of low-educated parents and of overweight and obese mothers spent less time watching TV or using the computer, and children of normal weight mothers drank less sweetened beverages (P<.05) compared with the control group. The E-health4Uth Healthy Toddler intervention resulted in small improvements in health-related behaviors among subgroups but had no significant effects with respect to the children's BMI. We conclude that the E-health4Uth Healthy Toddler intervention may be useful for pediatric health care professionals in terms of providing parents with personalized information regarding their child's health-related behaviors. Netherlands Trial Register: NTR1831; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1831 (Archived by WebCite at http://www.webcitation.org/6mm5YFOB0). ©Amy van Grieken, Eline Vlasblom, Lu Wang, Maaike Beltman, Magda M Boere-Boonekamp, Monique P L'Hoir, Hein Raat. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 27.07.2017.

Widespread covariation of early environmental exposures and trait-associated polygenic variation.

PubMed

Krapohl, E; Hannigan, L J; Pingault, J-B; Patel, H; Kadeva, N; Curtis, C; Breen, G; Newhouse, S J; Eley, T C; O'Reilly, P F; Plomin, R

2017-10-31

Although gene-environment correlation is recognized and investigated by family studies and recently by SNP-heritability studies, the possibility that genetic effects on traits capture environmental risk factors or protective factors has been neglected by polygenic prediction models. We investigated covariation between trait-associated polygenic variation identified by genome-wide association studies (GWASs) and specific environmental exposures, controlling for overall genetic relatedness using a genomic relatedness matrix restricted maximum-likelihood model. In a UK-representative sample ( n = 6,710), we find widespread covariation between offspring trait-associated polygenic variation and parental behavior and characteristics relevant to children's developmental outcomes-independently of population stratification. For instance, offspring genetic risk for schizophrenia was associated with paternal age ( R 2 = 0.002; P = 1e-04), and offspring education-associated variation was associated with variance in breastfeeding ( R 2 = 0.021; P = 7e-30), maternal smoking during pregnancy ( R 2 = 0.008; P = 5e-13), parental smacking ( R 2 = 0.01; P = 4e-15), household income ( R 2 = 0.032; P = 1e-22), watching television ( R 2 = 0.034; P = 5e-47), and maternal education ( R 2 = 0.065; P = 3e-96). Education-associated polygenic variation also captured covariation between environmental exposures and children's inattention/hyperactivity, conduct problems, and educational achievement. The finding that genetic variation identified by trait GWASs partially captures environmental risk factors or protective factors has direct implications for risk prediction models and the interpretation of GWAS findings.

[Sedentary leisure time and food consumption among Brazilian adolescents: the Brazilian National School-Based Adolescent Health Survey (PeNSE), 2009].

PubMed

Camelo, Lidyane do Valle; Rodrigues, Jôsi Fernandes de Castro; Giatti, Luana; Barreto, Sandhi Maria

2012-11-01

The objective of this paper was to investigate whether sedentary leisure time was associated with increased regular consumption of unhealthy foods, independently of socio-demographic indicators and family context. The analysis included 59,809 students from the Brazilian National School-Based Adolescent Health Survey (PeNSE) in 2009. The response variable was sedentary leisure time, defined as watching more than two hours of TV daily. The target explanatory variables were regular consumption of soft drinks, sweets, cookies, and processed meat. Odds ratios (OR) and 95% confidence limits (95%CI) were obtained by multiple logistic regression. Prevalence of sedentary leisure time was 65%. Regular consumption of unhealthy foods was statistically higher among students reporting sedentary leisure time, before and after adjusting for sex, age, skin color, school administration (public versus private), household assets index, and household composition. The results indicate the need for integrated interventions to promote healthy leisure-time activities and healthy eating habits among young people.

Accelerated echo planar J-resolved spectroscopic imaging in prostate cancer: a pilot validation of non-linear reconstruction using total variation and maximum entropy.

PubMed

Nagarajan, Rajakumar; Iqbal, Zohaib; Burns, Brian; Wilson, Neil E; Sarma, Manoj K; Margolis, Daniel A; Reiter, Robert E; Raman, Steven S; Thomas, M Albert

2015-11-01

The overlap of metabolites is a major limitation in one-dimensional (1D) spectral-based single-voxel MRS and multivoxel-based MRSI. By combining echo planar spectroscopic imaging (EPSI) with a two-dimensional (2D) J-resolved spectroscopic (JPRESS) sequence, 2D spectra can be recorded in multiple locations in a single slice of prostate using four-dimensional (4D) echo planar J-resolved spectroscopic imaging (EP-JRESI). The goal of the present work was to validate two different non-linear reconstruction methods independently using compressed sensing-based 4D EP-JRESI in prostate cancer (PCa): maximum entropy (MaxEnt) and total variation (TV). Twenty-two patients with PCa with a mean age of 63.8 years (range, 46-79 years) were investigated in this study. A 4D non-uniformly undersampled (NUS) EP-JRESI sequence was implemented on a Siemens 3-T MRI scanner. The NUS data were reconstructed using two non-linear reconstruction methods, namely MaxEnt and TV. Using both TV and MaxEnt reconstruction methods, the following observations were made in cancerous compared with non-cancerous locations: (i) higher mean (choline + creatine)/citrate metabolite ratios; (ii) increased levels of (choline + creatine)/spermine and (choline + creatine)/myo-inositol; and (iii) decreased levels of (choline + creatine)/(glutamine + glutamate). We have shown that it is possible to accelerate the 4D EP-JRESI sequence by four times and that the data can be reliably reconstructed using the TV and MaxEnt methods. The total acquisition duration was less than 13 min and we were able to detect and quantify several metabolites. Copyright © 2015 John Wiley & Sons, Ltd.

Total variation regularization of the 3-D gravity inverse problem using a randomized generalized singular value decomposition

NASA Astrophysics Data System (ADS)

Vatankhah, Saeed; Renaut, Rosemary A.; Ardestani, Vahid E.

2018-04-01

We present a fast algorithm for the total variation regularization of the 3-D gravity inverse problem. Through imposition of the total variation regularization, subsurface structures presenting with sharp discontinuities are preserved better than when using a conventional minimum-structure inversion. The associated problem formulation for the regularization is nonlinear but can be solved using an iteratively reweighted least-squares algorithm. For small-scale problems the regularized least-squares problem at each iteration can be solved using the generalized singular value decomposition. This is not feasible for large-scale, or even moderate-scale, problems. Instead we introduce the use of a randomized generalized singular value decomposition in order to reduce the dimensions of the problem and provide an effective and efficient solution technique. For further efficiency an alternating direction algorithm is used to implement the total variation weighting operator within the iteratively reweighted least-squares algorithm. Presented results for synthetic examples demonstrate that the novel randomized decomposition provides good accuracy for reduced computational and memory demands as compared to use of classical approaches.

Emergency department visits during an Olympic gold medal television broadcast

PubMed Central

Redelmeier, Donald A; Vermeulen, Marian J

2011-01-01

Background Practice pattern variations are often attributed to physician decision-making with no accounting for patient preferences. Objective To test whether a mass media television broadcast unrelated to health was associated with changes in the rate and characteristics of visits for acute emergency care. Design Time-series analysis of emergency department visits for any reason. Subjects Population-based sample of all patients seeking emergency care in Ontario, Canada. Measures The broadcast day was defined as the Olympic men’s gold medal ice hockey game final. The control days were defined as the 6 Sundays before and after the broadcast day. Results A total of 99 447 visits occurred over the 7 Sundays, of which 13 990 occurred on the broadcast day. Comparing the broadcast day with control days, we found no significant difference in the hourly rate of visits before the broadcast (544 vs 537, p = 0.41) or after the broadcast (647 vs 639, p = 0.55). In contrast, we observed a significant reduction in hourly rate of visits during the broadcast (647 vs 783, p < 0.001), equal to an absolute decrease of 409 patients, a relative decrease of 17% (95% confidence interval 13–21), or about 136 fewer patients per hour. The relative decrease during the broadcast was particularly large for adult men with low triage severity. The greatest reductions were for patients with abdominal, musculoskeletal or traumatic disorders. Conclusion Mass media television broadcasts can influence patient preferences and thereby lead to a decrease in emergency department visits. PMID:21915235

LH2 tank pressure control by thermodynamic vent system (TVS) at zero gravity

NASA Astrophysics Data System (ADS)

Wang, B.; Huang, Y. H.; Chen, Z. C.; Wu, J. Y.; Li, P.; Sun, P. J.

2017-02-01

Thermodynamic vent system (TVS) is employed for pressure control of propellant tanks at zero gravity. An analytical lumped parameter model is developed to predict pressure variation in an 18.09 m3 liquid hydrogen tank equipped with TVS. Mathematical simulations are carried out assuming tank is filled up to 75% volume (liquid mass equals to 945 kg) and is subjected to heat flux of 0.76 W/m2. Tank pressure controls at 165.5-172.4, 165.5-179.3 and 165.5-182.2 kPa are compared with reference to number of vent cycles, vent duration per cycle and loss of hydrogen. Analysis results indicate that the number of vent cycles significantly decreases from 62 to 21 when tank pressure control increases from 6.9 to 20.4 kPa. Also, duration of vent cycle increases from 63 to 152 and cycle duration decreases from 3920 to 3200 s. Further, the analysis result suggests that LH2 evaporation loss per day decreases from 0.17 to 0.14%. Based on the results of analysis, TVS is found effective in controlling the propellant tank pressure in zero gravity.

This Ad is for You: Targeting and the Effect of Alcohol Advertising on Youth Drinking.

PubMed

Molloy, Eamon

2016-02-01

Endogenous targeting of alcohol advertisements presents a challenge for empirically identifying a causal effect of advertising on drinking. Drinkers prefer a particular media; firms recognize this and target alcohol advertising at these media. This paper overcomes this challenge by utilizing novel data with detailed individual measures of media viewing and alcohol consumption and three separate empirical techniques, which represent significant improvements over previous methods. First, controls for the average audience characteristics of the media an individual views account for attributes of magazines and television programs alcohol firms may consider when deciding where to target advertising. A second specification directly controls for each television program and magazine a person views. The third method exploits variation in advertising exposure due to a 2003 change in an industry-wide rule that governs where firms may advertise. Although the unconditional correlation between advertising and drinking by youth (ages 18-24) is strong, models that include simple controls for targeting imply, at most, a modest advertising effect. Although the coefficients are estimated less precisely, estimates with models including more rigorous controls for targeting indicate no significant effect of advertising on youth drinking. Copyright © 2015 John Wiley & Sons, Ltd.

Low-dose X-ray computed tomography image reconstruction with a combined low-mAs and sparse-view protocol.

PubMed

Gao, Yang; Bian, Zhaoying; Huang, Jing; Zhang, Yunwan; Niu, Shanzhou; Feng, Qianjin; Chen, Wufan; Liang, Zhengrong; Ma, Jianhua

2014-06-16

To realize low-dose imaging in X-ray computed tomography (CT) examination, lowering milliampere-seconds (low-mAs) or reducing the required number of projection views (sparse-view) per rotation around the body has been widely studied as an easy and effective approach. In this study, we are focusing on low-dose CT image reconstruction from the sinograms acquired with a combined low-mAs and sparse-view protocol and propose a two-step image reconstruction strategy. Specifically, to suppress significant statistical noise in the noisy and insufficient sinograms, an adaptive sinogram restoration (ASR) method is first proposed with consideration of the statistical property of sinogram data, and then to further acquire a high-quality image, a total variation based projection onto convex sets (TV-POCS) method is adopted with a slight modification. For simplicity, the present reconstruction strategy was termed as "ASR-TV-POCS." To evaluate the present ASR-TV-POCS method, both qualitative and quantitative studies were performed on a physical phantom. Experimental results have demonstrated that the present ASR-TV-POCS method can achieve promising gains over other existing methods in terms of the noise reduction, contrast-to-noise ratio, and edge detail preservation.

[Computer optical topography: a study of the repeatability of the results of human body model examination].

PubMed

Sarnadskiĭ, V N

2007-01-01

The problem of repeatability of the results of examination of a plastic human body model is considered. The model was examined in 7 positions using an optical topograph for kyphosis diagnosis. The examination was performed under television camera monitoring. It was shown that variation of the model position in the camera view affected the repeatability of the results of topographic examination, especially if the model-to-camera distance was changed. A study of the repeatability of the results of optical topographic examination can help to increase the reliability of the topographic method, which is widely used for medical screening of children and adolescents.

Can gossip change nutrition behaviour? Results of a mass media and community-based intervention trial in East Java, Indonesia.

PubMed

White, Sian; Schmidt, Wolf; Sahanggamu, Daniel; Fatmaningrum, Dewi; van Liere, Marti; Curtis, Val

2016-03-01

It is unclear how best to go about improving child feeding practices. We studied the effect of a novel behaviour change intervention, Gerakan Rumpi Sehat (the Healthy Gossip Movement), on infant and young child feeding practices in peri-urban Indonesia. The pilot intervention was designed based on the principles of a new behaviour change theory, Behaviour Centred Design (BCD). It avoided educational messaging in favour of employing emotional drivers of behaviour change, such as affiliation, nurture and disgust and used television commercials, community activations and house-to-house visits as delivery channels. The evaluation took the form of a 2-arm cluster randomised trial with a non-randomised control arm. One intervention arm received TV only, while the other received TV plus community activations. The intervention components were delivered over a 3-month period in 12 villages in each arm, each containing an average of 1300 households. There were two primary outcomes: dietary diversity of complementary food and the provision of unhealthy snacks to children aged 6-24 months. Dietary diversity scores increased by 0.8 points in the arm exposed to TV adverts only (95% CI: 0.4-1.2) and a further 0.2 points in the arm that received both intervention components (95% CI: 0.6-1.4). In both intervention arms, there were increases in the frequency of vegetable and fruit intake. We found inconsistent evidence of an effect on unhealthy snacking. The study suggests that novel theory-driven approaches which employ emotional motivators are capable of having an effect on improving dietary diversity and the regularity of vegetable and fruit intake among children aged 6-24 months. Mass media can have a measurable effect on nutrition-related behaviour, but these effects are likely to be enhanced through complementary community activations. Changing several behaviours at once remains a challenge. © 2016 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

A feature alignment score for online cone-beam CT-based image-guided radiotherapy for prostate cancer.

PubMed

Hargrave, Catriona; Deegan, Timothy; Poulsen, Michael; Bednarz, Tomasz; Harden, Fiona; Mengersen, Kerrie

2018-05-17

To develop a method for scoring online cone-beam CT (CBCT)-to-planning CT image feature alignment to inform prostate image-guided radiotherapy (IGRT) decision-making. The feasibility of incorporating volume variation metric thresholds predictive of delivering planned dose into weighted functions, was investigated. Radiation therapists and radiation oncologists participated in workshops where they reviewed prostate CBCT-IGRT case examples and completed a paper-based survey of image feature matching practices. For 36 prostate cancer patients, one daily CBCT was retrospectively contoured then registered with their plan to simulate delivered dose if (a) no online setup corrections and (b) online image alignment and setup corrections, were performed. Survey results were used to select variables for inclusion in classification and regression tree (CART) and boosted regression trees (BRT) modeling of volume variation metric thresholds predictive of delivering planned dose to the prostate, proximal seminal vesicles (PSV), bladder, and rectum. Weighted functions incorporating the CART and BRT results were used to calculate a score of individual tumor and organ at risk image feature alignment (FAS TV _ OAR ). Scaled and weighted FAS TV _ OAR were then used to calculate a score of overall treatment compliance (FAS global ) for a given CBCT-planning CT registration. The FAS TV _ OAR were assessed for sensitivity, specificity, and predictive power. FAS global thresholds indicative of high, medium, or low overall treatment plan compliance were determined using coefficients from multiple linear regression analysis. Thirty-two participants completed the prostate CBCT-IGRT survey. While responses demonstrated consensus of practice for preferential ranking of planning CT and CBCT match features in the presence of deformation and rotation, variation existed in the specified thresholds for observed volume differences requiring patient repositioning or repeat bladder and bowel preparation. The CART and BRT modeling indicated that for a given registration, a Dice similarity coefficient >0.80 and >0.60 for the prostate and PSV, respectively, and a maximum Hausdorff distance <8.0 mm for both structures were predictive of delivered dose ± 5% of planned dose. A normalized volume difference <1.0 and a CBCT anterior rectum wall >1.0 mm anterior to the planning CT anterior rectum wall were predictive of delivered dose >5% of planned rectum dose. A normalized volume difference <0.88, and a CBCT bladder wall >13.5 mm inferior and >5.0 mm posterior to the planning CT bladder were predictive of delivered dose >5% of planned bladder dose. A FAS TV _ OAR >0 is indicative of delivery of planned dose. For calculated FAS TV _ OAR for the prostate, PSV, bladder, and rectum using test data, sensitivity was 0.56, 0.75, 0.89, and 1.00, respectively; specificity 0.90, 0.94, 0.59, and 1.00, respectively; positive predictive power 0.90, 0.86, 0.53, and 1.00, respectively; and negative predictive power 0.56, 0.89, 0.91, and 1.00, respectively. Thresholds for the calculated FAS global of were low <60, medium 60-80, and high >80, with a 27% misclassification rate for the test data. A FAS global incorporating nested FAS TV _ OAR and volume variation metric thresholds predictive of treatment plan compliance was developed, offering an alternative to pretreatment dose calculations to assess treatment delivery accuracy. © 2018 American Association of Physicists in Medicine.

Results of TV imaging of Phobos - Experiment VSK-Fregat

NASA Technical Reports Server (NTRS)

Avanesov, G.; Zhukov, B.; Ziman, IA.; Kostenko, V.; Kuz'min, A.; Duxbury, T.

1991-01-01

From February to March 1989 the Phobos 2 spacecraft took 37 TV images of Phobos at a distance of 190-1100 km. These images complement Mariner-9 and Viking data by providing higher-resolution coverage of a laarge region west of the crater Stickney (40-160 deg W) and by providing disk-resolved measurements of surface brightness at a greater range of wavelengths and additional phase angles. These images have supported updated mapping and characterization of large craters and grooves, and have provided additional observations of craters' and grooves' bright rims. Variations in surface visible/near-infrared color ratio of almost a factor of 2 have been recognized; these variations appear to be associated with the ejecta of specific large impact craters. Updated determinations of satellite mass and volume allow calculation of a more accurate value of bulk density, 1.90 + or - 0.1 g/cu cm. This is sigificantly lower than the density of meteoritic analogs to Phobos' surface, suggesting a porous interior perhaps containing interstitial ice.

Accelerating an Ordered-Subset Low-Dose X-Ray Cone Beam Computed Tomography Image Reconstruction with a Power Factor and Total Variation Minimization.

PubMed

Huang, Hsuan-Ming; Hsiao, Ing-Tsung

2016-01-01

In recent years, there has been increased interest in low-dose X-ray cone beam computed tomography (CBCT) in many fields, including dentistry, guided radiotherapy and small animal imaging. Despite reducing the radiation dose, low-dose CBCT has not gained widespread acceptance in routine clinical practice. In addition to performing more evaluation studies, developing a fast and high-quality reconstruction algorithm is required. In this work, we propose an iterative reconstruction method that accelerates ordered-subsets (OS) reconstruction using a power factor. Furthermore, we combine it with the total-variation (TV) minimization method. Both simulation and phantom studies were conducted to evaluate the performance of the proposed method. Results show that the proposed method can accelerate conventional OS methods, greatly increase the convergence speed in early iterations. Moreover, applying the TV minimization to the power acceleration scheme can further improve the image quality while preserving the fast convergence rate.

Accelerating an Ordered-Subset Low-Dose X-Ray Cone Beam Computed Tomography Image Reconstruction with a Power Factor and Total Variation Minimization

PubMed Central

Huang, Hsuan-Ming; Hsiao, Ing-Tsung

2016-01-01

In recent years, there has been increased interest in low-dose X-ray cone beam computed tomography (CBCT) in many fields, including dentistry, guided radiotherapy and small animal imaging. Despite reducing the radiation dose, low-dose CBCT has not gained widespread acceptance in routine clinical practice. In addition to performing more evaluation studies, developing a fast and high-quality reconstruction algorithm is required. In this work, we propose an iterative reconstruction method that accelerates ordered-subsets (OS) reconstruction using a power factor. Furthermore, we combine it with the total-variation (TV) minimization method. Both simulation and phantom studies were conducted to evaluate the performance of the proposed method. Results show that the proposed method can accelerate conventional OS methods, greatly increase the convergence speed in early iterations. Moreover, applying the TV minimization to the power acceleration scheme can further improve the image quality while preserving the fast convergence rate. PMID:27073853

Sources of strength-training information and strength-training behavior among Japanese older adults.

PubMed

Harada, Kazuhiro; Shibata, Ai; Lee, Euna; Oka, Koichiro; Nakamura, Yoshio

2016-03-01

The promotion of strength training is now recognized as an important component of public health initiatives for older adults. To develop successful communication strategies to increase strength-training behavior among older adults, the identification of effective communication channels to reach older adults is necessary. This study aimed to identify the information sources about strength training that were associated with strength-training behaviors among Japanese older adults. The participants were 1144 adults (60-74 years old) randomly sampled from the registry of residential addresses. A cross-sectional questionnaire survey was conducted. The independent variables were sources of strength-training information (healthcare providers, friends, families, radio, television, newspapers, newsletters, posters, books, magazines, booklets, the Internet, lectures, other sources), and the dependent variable was regular strength-training behavior. Logistic regression analysis was used to identify potential relationships. After adjusting for demographic factors and all other information sources, strength-training information from healthcare providers, friends, books and the Internet were positively related to regular strength-training behavior. The findings of the present study contribute to a better understanding of strength-training behavior and the means of successful communication directed at increasing strength training among older adults. The results suggest that healthcare providers, friends, books and the Internet are effective methods of communication for increasing strength-training behaviors among older adults. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

APPLICATION OF INFORMATION AND COMMUNICATION TECHNOLOGIES IN MEDICAL EDUCATION

PubMed Central

Al-Tamimi, Dalal M.

2003-01-01

The recognition that information and communication technologies should play an increasingly important role in medical education is a key to educating physicians in the 21st century. Computer use in medical education includes, Internet hypermedia/multimedia technologies, medical informatics, distance learning and telemedicine. Adaptation to the use of these technologies should ideally start from the elementary school level. Medical schools must introduce medical informatics courses very early in the medical curriculum. Teachers will need regular CME courses to prepare and update themselves with the changing circumstances. Our infrastructure must be prepared for the new developments with computer labs, basic skill labs, close circuit television facilities, virtual class rooms, smart class rooms, simulated teaching facilities, and distance teaching by tele-techniques. Our existing manpower including, doctors, nurses, technicians, librarians, and administration personal require hands-on training, while new recruitment will have to emphasize compulsory knowledge of and familiarity with information technology. This paper highlights these subjects in detail as a means to prepare us to meet the challenges of the 21st century. PMID:23011983

Sequentially reweighted TV minimization for CT metal artifact reduction.

PubMed

Zhang, Xiaomeng; Xing, Lei

2013-07-01

Metal artifact reduction has long been an important topic in x-ray CT image reconstruction. In this work, the authors propose an iterative method that sequentially minimizes a reweighted total variation (TV) of the image and produces substantially artifact-reduced reconstructions. A sequentially reweighted TV minimization algorithm is proposed to fully exploit the sparseness of image gradients (IG). The authors first formulate a constrained optimization model that minimizes a weighted TV of the image, subject to the constraint that the estimated projection data are within a specified tolerance of the available projection measurements, with image non-negativity enforced. The authors then solve a sequence of weighted TV minimization problems where weights used for the next iteration are computed from the current solution. Using the complete projection data, the algorithm first reconstructs an image from which a binary metal image can be extracted. Forward projection of the binary image identifies metal traces in the projection space. The metal-free background image is then reconstructed from the metal-trace-excluded projection data by employing a different set of weights. Each minimization problem is solved using a gradient method that alternates projection-onto-convex-sets and steepest descent. A series of simulation and experimental studies are performed to evaluate the proposed approach. Our study shows that the sequentially reweighted scheme, by altering a single parameter in the weighting function, flexibly controls the sparsity of the IG and reconstructs artifacts-free images in a two-stage process. It successfully produces images with significantly reduced streak artifacts, suppressed noise and well-preserved contrast and edge properties. The sequentially reweighed TV minimization provides a systematic approach for suppressing CT metal artifacts. The technique can also be generalized to other "missing data" problems in CT image reconstruction.

Fast alternating projection methods for constrained tomographic reconstruction

PubMed Central

Liu, Li; Han, Yongxin

2017-01-01

The alternating projection algorithms are easy to implement and effective for large-scale complex optimization problems, such as constrained reconstruction of X-ray computed tomography (CT). A typical method is to use projection onto convex sets (POCS) for data fidelity, nonnegative constraints combined with total variation (TV) minimization (so called TV-POCS) for sparse-view CT reconstruction. However, this type of method relies on empirically selected parameters for satisfactory reconstruction and is generally slow and lack of convergence analysis. In this work, we use a convex feasibility set approach to address the problems associated with TV-POCS and propose a framework using full sequential alternating projections or POCS (FS-POCS) to find the solution in the intersection of convex constraints of bounded TV function, bounded data fidelity error and non-negativity. The rationale behind FS-POCS is that the mathematically optimal solution of the constrained objective function may not be the physically optimal solution. The breakdown of constrained reconstruction into an intersection of several feasible sets can lead to faster convergence and better quantification of reconstruction parameters in a physical meaningful way than that in an empirical way of trial-and-error. In addition, for large-scale optimization problems, first order methods are usually used. Not only is the condition for convergence of gradient-based methods derived, but also a primal-dual hybrid gradient (PDHG) method is used for fast convergence of bounded TV. The newly proposed FS-POCS is evaluated and compared with TV-POCS and another convex feasibility projection method (CPTV) using both digital phantom and pseudo-real CT data to show its superior performance on reconstruction speed, image quality and quantification. PMID:28253298

Relationships between in vivo dynamic knee joint loading, static alignment and tibial subchondral bone microarchitecture in end-stage knee osteoarthritis.

PubMed

Roberts, B C; Solomon, L B; Mercer, G; Reynolds, K J; Thewlis, D; Perilli, E

2018-04-01

To study, in end-stage knee osteoarthritis (OA) patients, relationships between indices of in vivo dynamic knee joint loads obtained pre-operatively using gait analysis, static knee alignment, and the subchondral trabecular bone (STB) microarchitecture of their excised tibial plateau quantified with 3D micro-CT. Twenty-five knee OA patients scheduled for total knee arthroplasty underwent pre-operative gait analysis. Mechanical axis deviation (MAD) was determined radiographically. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four subregions (anteromedial, posteromedial, anterolateral, posterolateral). Regional differences in STB microarchitecture and relationships between joint loading and microarchitecture were examined. STB microarchitecture differed among subregions (P < 0.001), anteromedially exhibiting highest bone volume fraction (BV/TV) and lowest structure model index (SMI). Anteromedial BV/TV and SMI correlated strongest with the peak external rotation moment (ERM; r = -0.74, r = 0.67, P < 0.01), despite ERM being the lowest (by factor of 10) of the moments considered, with majority of ERM measures below accuracy thresholds; medial-to-lateral BV/TV ratios correlated with ERM, MAD, knee adduction moment (KAM) and internal rotation moment (|r|-range: 0.54-0.74). When controlling for walking speed, KAM and MAD, the ERM explained additional 11-30% of the variations in anteromedial BV/TV and medial-to-lateral BV/TV ratio (R 2  = 0.59, R 2  = 0.69, P < 0.01). This preliminary study suggests significant associations between tibial plateau STB microarchitecture and knee joint loading indices in end-stage knee OA patients. Particularly, anteromedial BV/TV correlates strongest with ERM, whereas medial-to-lateral BV/TV ratio correlates strongest with indicators of medial-to-lateral joint loading (MAD, KAM) and rotational moments. However, associations with ERM should be interpreted with caution. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Controlled wavelet domain sparsity for x-ray tomography

NASA Astrophysics Data System (ADS)

Purisha, Zenith; Rimpeläinen, Juho; Bubba, Tatiana; Siltanen, Samuli

2018-01-01

Tomographic reconstruction is an ill-posed inverse problem that calls for regularization. One possibility is to require sparsity of the unknown in an orthonormal wavelet basis. This, in turn, can be achieved by variational regularization, where the penalty term is the sum of the absolute values of the wavelet coefficients. The primal-dual fixed point algorithm showed that the minimizer of the variational regularization functional can be computed iteratively using a soft-thresholding operation. Choosing the soft-thresholding parameter \

[Pregnancy and childbirth in a patient with a spinal cord lesion].

PubMed

Vanderbeke, I; Boll, D; Verguts, J K

2008-05-17

A 37-year-old woman with a spinal cord lesion at the level of TvIII due to a car-accident, became pregnant. She had posttraumatic syringomyely at Cv-TvIII, for which she underwent syringo-arachnoidal drainage. At approximately six weeks of amenorrhoea she presented at the emergency room with vaginal bleeding. She was treated with dalteparine 5000 IU once daily given by intramuscular injection until 6 weeks post partum. Weekly urine checks were advised. At 36 6/7 weeks of pregnancy, the patient was admitted to hospital for daily cardiotocography and 4-hourly contraction monitoring. After spontaneous rupture of the membranes she went into labour and had a vaginal delivery of a son weighing 3320 g. His Apgar score was 6 after 1 min and 9 after 5 min; arterial pH was 7.31. For three months after giving birth she received specialist care at home as well as help and counselling from a rehabilitation centre. In pregnant women with a spinal cord lesion, special attention should be paid to urinary tract infections, pressure areas, anaemia and thrombo-embolic symptoms. During partus, cardiotocographic monitoring should be carried out, also in patients with TvI-Tx lesions regularly from 36 weeks. In pregnant women with lesions from TvI, medical attendants should be aware of the possibility of autonomous dysreflection. Epidural anaesthesia should be administered and episiotomy or rupture avoided. Post partum, the bladder should always be completely emptied and pressure areas and signs ofthrombo-embolic complications monitored. A urological bladder function consultation should be requested, and, ifepisiotomy or rupture does occur, extra care should be taken to avoid infection. The ergonomic situation at home should be evaluated to ensure that any ergonomic changes necessary for the care of the patient and her newborn, take place in time.

Marketing communication in the area of breast and cervical cancer prevention.

PubMed

Cvijović, Jelena; Milica Kostić-Stanković; Krstić, Goran; Stojanović, Ljupce

2016-06-01

Innovative marketing campaigns and promotional activities can successfully contribute to the improvement of public health by raising the level of general knowledge about health issues and benefits that the change of habits, eradication of undesirable behaviour and regular medical controls have. The focus should be on continuous marketing communication through various mass media or direct communication between medical staff and patients. The aim of this paper was to define the role that various communication channels have in the process of informing and educating the target group in case of breast and cervical cancer prevention. The survey based on polling a sample of 2,100 female patients of the Serbian Railways Medical Centre was conducted in the period October- December 2013. The questionnaire included questions about demographic characteristics, prevention habits of women, their level of information on that topic and communication channels they prefer. There is a difference among respondents' awareness level about preventive measures depending on demographic and geographical criteria. The results indicate the existence of variations in frequency of performing gynaecological examinations and Pap tests depending on different age, educational and residential groups. Although the largest percentage of women stated familiarity with the way of performing breast self-examination (78%), the majority of them had never performed mammography or ultrasonography (67%). The greatest number of women were informed about the possibility of preventing breast and cervical cancer by posters or brochures in health institutions (71%) and mass media--television on the first place (74%), then specialized magazines about health (48%), radio (48%), web sites about health (42%), and daily newspapers (34%). The respondents consider the Ministry of Health and health institutions as the most responsible subjects for education of women about cancer prevention, while the self-initiative was given the least importance. Determined informing habits of the target group, their prevention habits and attitudes on the subject should be used as the basis for planning and implementation of prevention marketing campaigns that would be the most effective.

SU-D-206-03: Segmentation Assisted Fast Iterative Reconstruction Method for Cone-Beam CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, P; Mao, T; Gong, S

2016-06-15

Purpose: Total Variation (TV) based iterative reconstruction (IR) methods enable accurate CT image reconstruction from low-dose measurements with sparse projection acquisition, due to the sparsifiable feature of most CT images using gradient operator. However, conventional solutions require large amount of iterations to generate a decent reconstructed image. One major reason is that the expected piecewise constant property is not taken into consideration at the optimization starting point. In this work, we propose an iterative reconstruction method for cone-beam CT (CBCT) using image segmentation to guide the optimization path more efficiently on the regularization term at the beginning of the optimizationmore » trajectory. Methods: Our method applies general knowledge that one tissue component in the CT image contains relatively uniform distribution of CT number. This general knowledge is incorporated into the proposed reconstruction using image segmentation technique to generate the piecewise constant template on the first-pass low-quality CT image reconstructed using analytical algorithm. The template image is applied as an initial value into the optimization process. Results: The proposed method is evaluated on the Shepp-Logan phantom of low and high noise levels, and a head patient. The number of iterations is reduced by overall 40%. Moreover, our proposed method tends to generate a smoother reconstructed image with the same TV value. Conclusion: We propose a computationally efficient iterative reconstruction method for CBCT imaging. Our method achieves a better optimization trajectory and a faster convergence behavior. It does not rely on prior information and can be readily incorporated into existing iterative reconstruction framework. Our method is thus practical and attractive as a general solution to CBCT iterative reconstruction. This work is supported by the Zhejiang Provincial Natural Science Foundation of China (Grant No. LR16F010001), National High-tech R&D Program for Young Scientists by the Ministry of Science and Technology of China (Grant No. 2015AA020917).« less

Shading correction assisted iterative cone-beam CT reconstruction

NASA Astrophysics Data System (ADS)

Yang, Chunlin; Wu, Pengwei; Gong, Shutao; Wang, Jing; Lyu, Qihui; Tang, Xiangyang; Niu, Tianye

2017-11-01

Recent advances in total variation (TV) technology enable accurate CT image reconstruction from highly under-sampled and noisy projection data. The standard iterative reconstruction algorithms, which work well in conventional CT imaging, fail to perform as expected in cone beam CT (CBCT) applications, wherein the non-ideal physics issues, including scatter and beam hardening, are more severe. These physics issues result in large areas of shading artifacts and cause deterioration to the piecewise constant property assumed in reconstructed images. To overcome this obstacle, we incorporate a shading correction scheme into low-dose CBCT reconstruction and propose a clinically acceptable and stable three-dimensional iterative reconstruction method that is referred to as the shading correction assisted iterative reconstruction. In the proposed method, we modify the TV regularization term by adding a shading compensation image to the reconstructed image to compensate for the shading artifacts while leaving the data fidelity term intact. This compensation image is generated empirically, using image segmentation and low-pass filtering, and updated in the iterative process whenever necessary. When the compensation image is determined, the objective function is minimized using the fast iterative shrinkage-thresholding algorithm accelerated on a graphic processing unit. The proposed method is evaluated using CBCT projection data of the Catphan© 600 phantom and two pelvis patients. Compared with the iterative reconstruction without shading correction, the proposed method reduces the overall CT number error from around 200 HU to be around 25 HU and increases the spatial uniformity by a factor of 20 percent, given the same number of sparsely sampled projections. A clinically acceptable and stable iterative reconstruction algorithm for CBCT is proposed in this paper. Differing from the existing algorithms, this algorithm incorporates a shading correction scheme into the low-dose CBCT reconstruction and achieves more stable optimization path and more clinically acceptable reconstructed image. The method proposed by us does not rely on prior information and thus is practically attractive to the applications of low-dose CBCT imaging in the clinic.

Editorial on Future Jet Technologies

NASA Astrophysics Data System (ADS)

Gal-Or, Benjamin

2014-12-01

The jet engine is the prime flight controller in post-stall flight domains where conventional flight control fails, or when the engine prevents catastrophes in training, combat, loss of all airframe hydraulics (the engine retains its own hydraulics), loss of one engine, pilot errors, icing on the wings, landing gear and runway issues in takeoff and landing and in bad-whether recoveries. The scientific term for this revolutionary technology is "jet-steering", and in engineering practice - "thrust vectoring", or "TV". Jet-Steering in advanced fighter aircraft designs is integrated with stealth technology. The resulting classified Thrust-Vectoring-Stealth ("TVS") technology has generated a second jet-revolution by which all Air-&-Sea-Propulsion Science and R&D are now being reassessed. Classified F-22, X-47B/C and RQ-180 TVS-vehicles stand at the front of this revolution. But recent transfers of such sensitive technologies to South Korea and Japan [1-5], have raised various fundamental issues that are evaluated by this editorial-review. One, and perhaps a key conclusion presented here, means that both South Korea and Japan may have missed one of their air-&-sea defenses: To develop and field low-cost unmanned fleets of jet-drones, some for use with expensive, TVS-fighter aircraft in highly congested areas. In turn, the U.S., EU, Russia and China, are currently developing such fleets at various TVS levels and sizes. China, for instance, operates at least 15,000 drones ("UAVs") by 2014 in the civilian sector alone. All Chinese drones have been developed by at least 230 developers/manufacturers [1-16]. Mobile telecommunication of safe links between flyers and combat drones ("UCAVs") at increasingly deep penetrations into remote, congested areas, can gradually be purchased-developed-deployed and then operated by extant cader of tens of thousands "National Champion Flyers" who have already mastered the operation of mini-drones in free-to-all sport clubs under national competions and Awards. [Rule-13]. We also provide 26 references [17-43] to a different, unclassified technology that enhances TV-induced flight safety for passenger jets, turboprops and helicopters. It is based on patented stowed-away/emergency-deployed TV-kits added to fixed-configuration, subsonic exhaust nozzles of low thrust-to-weight ratio vehicles. Expected benefits include anti-terror recoveries from emergencies, like forced landing on unprepared runways or highways, or recoveries from all airframe-hydraulics-outs, asymmetric ice on wings, landing gear catastrophes, and recoveries from pilot errors and bad-whether incidents [Rule 9(7)]. Other TV technologies involve preventing catastrophes in speed and patrol boats, racing and regular cars/SUVs, buses and trucks. [Rule 9(8)] and faster helicopters [Rule 9(10)].

3D first-arrival traveltime tomography with modified total variation regularization

NASA Astrophysics Data System (ADS)

Jiang, Wenbin; Zhang, Jie

2018-02-01

Three-dimensional (3D) seismic surveys have become a major tool in the exploration and exploitation of hydrocarbons. 3D seismic first-arrival traveltime tomography is a robust method for near-surface velocity estimation. A common approach for stabilizing the ill-posed inverse problem is to apply Tikhonov regularization to the inversion. However, the Tikhonov regularization method recovers smooth local structures while blurring the sharp features in the model solution. We present a 3D first-arrival traveltime tomography method with modified total variation (MTV) regularization to preserve sharp velocity contrasts and improve the accuracy of velocity inversion. To solve the minimization problem of the new traveltime tomography method, we decouple the original optimization problem into two following subproblems: a standard traveltime tomography problem with the traditional Tikhonov regularization and a L2 total variation problem. We apply the conjugate gradient method and split-Bregman iterative method to solve these two subproblems, respectively. Our synthetic examples show that the new method produces higher resolution models than the conventional traveltime tomography with Tikhonov regularization. We apply the technique to field data. The stacking section shows significant improvements with static corrections from the MTV traveltime tomography.

Low-dose X-ray computed tomography image reconstruction with a combined low-mAs and sparse-view protocol

PubMed Central

Gao, Yang; Bian, Zhaoying; Huang, Jing; Zhang, Yunwan; Niu, Shanzhou; Feng, Qianjin; Chen, Wufan; Liang, Zhengrong; Ma, Jianhua

2014-01-01

To realize low-dose imaging in X-ray computed tomography (CT) examination, lowering milliampere-seconds (low-mAs) or reducing the required number of projection views (sparse-view) per rotation around the body has been widely studied as an easy and effective approach. In this study, we are focusing on low-dose CT image reconstruction from the sinograms acquired with a combined low-mAs and sparse-view protocol and propose a two-step image reconstruction strategy. Specifically, to suppress significant statistical noise in the noisy and insufficient sinograms, an adaptive sinogram restoration (ASR) method is first proposed with consideration of the statistical property of sinogram data, and then to further acquire a high-quality image, a total variation based projection onto convex sets (TV-POCS) method is adopted with a slight modification. For simplicity, the present reconstruction strategy was termed as “ASR-TV-POCS.” To evaluate the present ASR-TV-POCS method, both qualitative and quantitative studies were performed on a physical phantom. Experimental results have demonstrated that the present ASR-TV-POCS method can achieve promising gains over other existing methods in terms of the noise reduction, contrast-to-noise ratio, and edge detail preservation. PMID:24977611

Design of a model observer to evaluate calcification detectability in breast tomosynthesis and application to smoothing prior optimization.

PubMed

Michielsen, Koen; Nuyts, Johan; Cockmartin, Lesley; Marshall, Nicholas; Bosmans, Hilde

2016-12-01

In this work, the authors design and validate a model observer that can detect groups of microcalcifications in a four-alternative forced choice experiment and use it to optimize a smoothing prior for detectability of microcalcifications. A channelized Hotelling observer (CHO) with eight Laguerre-Gauss channels was designed to detect groups of five microcalcifications in a background of acrylic spheres by adding the CHO log-likelihood ratios calculated at the expected locations of the five calcifications. This model observer is then applied to optimize the detectability of the microcalcifications as a function of the smoothing prior. The authors examine the quadratic and total variation (TV) priors, and a combination of both. A selection of these reconstructions was then evaluated by human observers to validate the correct working of the model observer. The authors found a clear maximum for the detectability of microcalcification when using the total variation prior with weight β TV = 35. Detectability only varied over a small range for the quadratic and combined quadratic-TV priors when weight β Q of the quadratic prior was changed by two orders of magnitude. Spearman correlation with human observers was good except for the highest value of β for the quadratic and TV priors. Excluding those, the authors found ρ = 0.93 when comparing detection fractions, and ρ = 0.86 for the fitted detection threshold diameter. The authors successfully designed a model observer that was able to predict human performance over a large range of settings of the smoothing prior, except for the highest values of β which were outside the useful range for good image quality. Since detectability only depends weakly on the strength of the combined prior, it is not possible to pick an optimal smoothness based only on this criterion. On the other hand, such choice can now be made based on other criteria without worrying about calcification detectability.

Spatial Pyramid Covariance based Compact Video Code for Robust Face Retrieval in TV-series.

PubMed

Li, Yan; Wang, Ruiping; Cui, Zhen; Shan, Shiguang; Chen, Xilin

2016-10-10

We address the problem of face video retrieval in TV-series which searches video clips based on the presence of specific character, given one face track of his/her. This is tremendously challenging because on one hand, faces in TV-series are captured in largely uncontrolled conditions with complex appearance variations, and on the other hand retrieval task typically needs efficient representation with low time and space complexity. To handle this problem, we propose a compact and discriminative representation for the huge body of video data, named Compact Video Code (CVC). Our method first models the face track by its sample (i.e., frame) covariance matrix to capture the video data variations in a statistical manner. To incorporate discriminative information and obtain more compact video signature suitable for retrieval, the high-dimensional covariance representation is further encoded as a much lower-dimensional binary vector, which finally yields the proposed CVC. Specifically, each bit of the code, i.e., each dimension of the binary vector, is produced via supervised learning in a max margin framework, which aims to make a balance between the discriminability and stability of the code. Besides, we further extend the descriptive granularity of covariance matrix from traditional pixel-level to more general patchlevel, and proceed to propose a novel hierarchical video representation named Spatial Pyramid Covariance (SPC) along with a fast calculation method. Face retrieval experiments on two challenging TV-series video databases, i.e., the Big Bang Theory and Prison Break, demonstrate the competitiveness of the proposed CVC over state-of-the-art retrieval methods. In addition, as a general video matching algorithm, CVC is also evaluated in traditional video face recognition task on a standard Internet database, i.e., YouTube Celebrities, showing its quite promising performance by using an extremely compact code with only 128 bits.

An object-oriented simulator for 3D digital breast tomosynthesis imaging system.

PubMed

Seyyedi, Saeed; Cengiz, Kubra; Kamasak, Mustafa; Yildirim, Isa

2013-01-01

Digital breast tomosynthesis (DBT) is an innovative imaging modality that provides 3D reconstructed images of breast to detect the breast cancer. Projections obtained with an X-ray source moving in a limited angle interval are used to reconstruct 3D image of breast. Several reconstruction algorithms are available for DBT imaging. Filtered back projection algorithm has traditionally been used to reconstruct images from projections. Iterative reconstruction algorithms such as algebraic reconstruction technique (ART) were later developed. Recently, compressed sensing based methods have been proposed in tomosynthesis imaging problem. We have developed an object-oriented simulator for 3D digital breast tomosynthesis (DBT) imaging system using C++ programming language. The simulator is capable of implementing different iterative and compressed sensing based reconstruction methods on 3D digital tomosynthesis data sets and phantom models. A user friendly graphical user interface (GUI) helps users to select and run the desired methods on the designed phantom models or real data sets. The simulator has been tested on a phantom study that simulates breast tomosynthesis imaging problem. Results obtained with various methods including algebraic reconstruction technique (ART) and total variation regularized reconstruction techniques (ART+TV) are presented. Reconstruction results of the methods are compared both visually and quantitatively by evaluating performances of the methods using mean structural similarity (MSSIM) values.

Fast and low-dose computed laminography using compressive sensing based technique

NASA Astrophysics Data System (ADS)

Abbas, Sajid; Park, Miran; Cho, Seungryong

2015-03-01

Computed laminography (CL) is well known for inspecting microstructures in the materials, weldments and soldering defects in high density packed components or multilayer printed circuit boards. The overload problem on x-ray tube and gross failure of the radio-sensitive electronics devices during a scan are among important issues in CL which needs to be addressed. The sparse-view CL can be one of the viable option to overcome such issues. In this work a numerical aluminum welding phantom was simulated to collect sparsely sampled projection data at only 40 views using a conventional CL scanning scheme i.e. oblique scan. A compressive-sensing inspired total-variation (TV) minimization algorithm was utilized to reconstruct the images. It is found that the images reconstructed using sparse view data are visually comparable with the images reconstructed using full scan data set i.e. at 360 views on regular interval. We have quantitatively confirmed that tiny structures such as copper and tungsten slags, and copper flakes in the reconstructed images from sparsely sampled data are comparable with the corresponding structure present in the fully sampled data case. A blurring effect can be seen near the edges of few pores at the bottom of the reconstructed images from sparsely sampled data, despite the overall image quality is reasonable for fast and low-dose NDT.

An Object-Oriented Simulator for 3D Digital Breast Tomosynthesis Imaging System

PubMed Central

Cengiz, Kubra

2013-01-01

Digital breast tomosynthesis (DBT) is an innovative imaging modality that provides 3D reconstructed images of breast to detect the breast cancer. Projections obtained with an X-ray source moving in a limited angle interval are used to reconstruct 3D image of breast. Several reconstruction algorithms are available for DBT imaging. Filtered back projection algorithm has traditionally been used to reconstruct images from projections. Iterative reconstruction algorithms such as algebraic reconstruction technique (ART) were later developed. Recently, compressed sensing based methods have been proposed in tomosynthesis imaging problem. We have developed an object-oriented simulator for 3D digital breast tomosynthesis (DBT) imaging system using C++ programming language. The simulator is capable of implementing different iterative and compressed sensing based reconstruction methods on 3D digital tomosynthesis data sets and phantom models. A user friendly graphical user interface (GUI) helps users to select and run the desired methods on the designed phantom models or real data sets. The simulator has been tested on a phantom study that simulates breast tomosynthesis imaging problem. Results obtained with various methods including algebraic reconstruction technique (ART) and total variation regularized reconstruction techniques (ART+TV) are presented. Reconstruction results of the methods are compared both visually and quantitatively by evaluating performances of the methods using mean structural similarity (MSSIM) values. PMID:24371468

Fast Dictionary-Based Reconstruction for Diffusion Spectrum Imaging

PubMed Central

Bilgic, Berkin; Chatnuntawech, Itthi; Setsompop, Kawin; Cauley, Stephen F.; Yendiki, Anastasia; Wald, Lawrence L.; Adalsteinsson, Elfar

2015-01-01

Diffusion Spectrum Imaging (DSI) reveals detailed local diffusion properties at the expense of substantially long imaging times. It is possible to accelerate acquisition by undersampling in q-space, followed by image reconstruction that exploits prior knowledge on the diffusion probability density functions (pdfs). Previously proposed methods impose this prior in the form of sparsity under wavelet and total variation (TV) transforms, or under adaptive dictionaries that are trained on example datasets to maximize the sparsity of the representation. These compressed sensing (CS) methods require full-brain processing times on the order of hours using Matlab running on a workstation. This work presents two dictionary-based reconstruction techniques that use analytical solutions, and are two orders of magnitude faster than the previously proposed dictionary-based CS approach. The first method generates a dictionary from the training data using Principal Component Analysis (PCA), and performs the reconstruction in the PCA space. The second proposed method applies reconstruction using pseudoinverse with Tikhonov regularization with respect to a dictionary. This dictionary can either be obtained using the K-SVD algorithm, or it can simply be the training dataset of pdfs without any training. All of the proposed methods achieve reconstruction times on the order of seconds per imaging slice, and have reconstruction quality comparable to that of dictionary-based CS algorithm. PMID:23846466

Cross-cultural comparison of lack of regular physical activity among college students: Universal versus transversal.

PubMed

Seo, Dong-Chul; Torabi, Mohammad R; Jiang, Nan; Fernandez-Rojas, Xinia; Park, Bock-Hee

2009-01-01

This study examined cultural influence on personal and behavioral correlates of lack of regular physical activity (PA) among college students in four countries, i.e., the United States, Costa Rica, India, and South Korea. Public universities were randomly chosen among the four countries. A total of 4,685 students participated in the study during the 2006-2007 academic year with a response rate of 90.1%. The vast majority of the questions on the instrument were adopted from the Youth Risk Behavior Survey and the Behavioral Risk Factor Surveillance System questionnaires. The instrument was translated into Spanish and Korean and then back-translated into English to check accuracy of the translation. Low fruit consumption was a culture-universal predictor of lack of regular PA. Gender, perceived body weight, vegetable consumption, and cigarette smoking were culture-specific predictors, indicating PA might be a transversal value. Body mass index, binge drinking, and TV/video watching were not associated with lack of regular PA in any of the four countries. While PA is valued across different segments of many cultures, given the several culture-specific predictors, PA appears to be more transversal than universal. Therefore, culturally sensitive interventions are necessary to promote PA among young adults.

A self-administered Timeline Followback to measure variations in underage drinkers' alcohol intake and binge drinking.

PubMed

Collins, R Lorraine; Kashdan, Todd B; Koutsky, James R; Morsheimer, Elizabeth T; Vetter, Charlene J

2008-01-01

Underage drinkers typically have not developed regular patterns of drinking and so are likely to exhibit situational variation in alcohol intake, including binge drinking. Information about such variation is not well captured by quantity/frequency (QF) measures, which require that drinkers blend information over time to derive a representative estimate of "typical" drinking. The Timeline Followback (TLFB) method is designed to retrospectively capture situational variations in drinking during a specific period of time. We compared our newly-developed Self-administered TLFB (STLFB) measure to a QF measure for reporting alcohol intake. Our sample of 429 (men=204; women=225) underage (i.e., age 18-20 years) drinkers completed the two drinking measures and reported on alcohol problems. The STLFB and QF measures converged in assessing typical daily intake, but the STLFB provided more information about situational variations in alcohol use and better identification of regular versus intermittent binge drinkers. Regular binge drinkers reported more alcohol problems. The STLFB is an easy-to-administer measure of variations in alcohol intake, which can be useful for understanding drinking behavior.

Introduction of Total Variation Regularization into Filtered Backprojection Algorithm

NASA Astrophysics Data System (ADS)

Raczyński, L.; Wiślicki, W.; Klimaszewski, K.; Krzemień, W.; Kowalski, P.; Shopa, R. Y.; Białas, P.; Curceanu, C.; Czerwiński, E.; Dulski, K.; Gajos, A.; Głowacz, B.; Gorgol, M.; Hiesmayr, B.; Jasińska, B.; Kisielewska-Kamińska, D.; Korcyl, G.; Kozik, T.; Krawczyk, N.; Kubicz, E.; Mohammed, M.; Pawlik-Niedźwiecka, M.; Niedźwiecki, S.; Pałka, M.; Rudy, Z.; Sharma, N. G.; Sharma, S.; Silarski, M.; Skurzok, M.; Wieczorek, A.; Zgardzińska, B.; Zieliński, M.; Moskal, P.

In this paper we extend the state-of-the-art filtered backprojection (FBP) method with application of the concept of Total Variation regularization. We compare the performance of the new algorithm with the most common form of regularizing in the FBP image reconstruction via apodizing functions. The methods are validated in terms of cross-correlation coefficient between reconstructed and real image of radioactive tracer distribution using standard Derenzo-type phantom. We demonstrate that the proposed approach results in higher cross-correlation values with respect to the standard FBP method.

Physical activity in prevention and treatment of the metabolic syndrome.

PubMed

Lakka, Timo A; Laaksonen, David E

2007-02-01

Randomised controlled trials have shown that exercise training has a mild or moderate favourable effect on many metabolic and cardiovascular risk factors that constitute or are related to the metabolic syndrome (MetS). Epidemiological studies suggest that regular physical activity prevents type 2 diabetes, cardiovascular disease, and premature mortality in large part through these risk factors. Although randomized controlled trials with the prevention or treatment of the MetS as the main outcome have not been published, several large randomized controlled trials provide strong evidence that favourable lifestyle changes, including regular physical activity, are effective in the prevention of type 2 diabetes in individuals who are overweight and have impaired glucose tolerance. Compliance with the current recommendations to increase the total volume of moderate-intensity physical activity and to maintain good cardiorespiratory and muscular fitness appears to markedly decrease the likelihood of developing the MetS, especially in high-risk groups. Walking is the most common form of physical activity--it improves health in many ways and is generally safe. Therefore, brisk walking for at least 30 min daily can be recommended as the principal form of physical activity at the population level. If there are no contraindications, more vigorous physical exercise or resistance training should also be considered to obtain additional health benefits. Unstructured and low-intensity physical activity may also decrease the likelihood of developing the MetS, especially when substituted for sedentary behaviours such as watching television. The measurement of maximal oxygen consumption may provide an efficient means to target even individuals with relatively few metabolic risk factors who may benefit from more intensive intervention.

Exposure to advertising and perception, interest, and use of e-cigarettes among adolescents: findings from the US National Youth Tobacco Survey.

PubMed

Pu, Jia; Zhang, Xiao

2017-11-01

US adolescents are exposed to high levels of advertisements for electronic cigarettes (e-cigarettes). This study aimed to examine the associations between exposure to e-cigarette advertisements and perception, interest, and use of e-cigarettes among US middle school and high school students. Data from the 2014 cross-sectional National Youth Tobacco Survey were used. Logistic regressions were conducted to model four outcomes, including perception of reduced harmfulness compared to regular cigarettes, perception of reduced addictiveness, intention to use, and current use of e-cigarettes. Main predictors were exposure to e-cigarette advertisements via four sources, including Internet, newspaper/magazines, retail stores, and TV. When all the four sources of e-cigarette advertisements exposure were evaluated jointly, exposure via the Internet was associated with elevated likelihood of reporting all four outcomes related to e-cigarettes, while exposure via retail stores was associated with higher likelihood of current e-cigarette use and perception of reduced harmfulness of e-cigarettes compared to regular cigarettes ( p < .05). However, exposure via newspaper/magazines and TV was associated with lower likelihood of perceiving e-cigarettes to be less harmful or addictive ( p < .05). Exposure to e-cigarette advertisements via the Internet and retail stores may play a significant role in adolescents' use and perception of e-cigarettes. The results call for more research on the influence of different sources of advertising exposure on e-cigarette use to help public health programmes curtail the fast growing use of e-cigarette products among youth.

76 FR 72849 - Digital Low Power Television, Television Translator, and Television Booster Stations and To Amend...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

...] Digital Low Power Television, Television Translator, and Television Booster Stations and To Amend Rules... for Digital Low Power Television, Television Translator, and Television Booster Stations and to Amend... television, TV translator, and Class A television station DTV licensees''). The Commission has also revised...

Regularization by Functions of Bounded Variation and Applications to Image Enhancement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casas, E.; Kunisch, K.; Pola, C.

1999-09-15

Optimization problems regularized by bounded variation seminorms are analyzed. The optimality system is obtained and finite-dimensional approximations of bounded variation function spaces as well as of the optimization problems are studied. It is demonstrated that the choice of the vector norm in the definition of the bounded variation seminorm is of special importance for approximating subspaces consisting of piecewise constant functions. Algorithms based on a primal-dual framework that exploit the structure of these nondifferentiable optimization problems are proposed. Numerical examples are given for denoising of blocky images with very high noise.

47 CFR 73.3521 - Mutually exclusive applications for low power television, television translators and television...

Code of Federal Regulations, 2013 CFR

2013-10-01

... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...

47 CFR 73.3521 - Mutually exclusive applications for low power television, television translators and television...

Code of Federal Regulations, 2012 CFR

2012-10-01

... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...

47 CFR 73.3521 - Mutually exclusive applications for low power television, television translators and television...

Code of Federal Regulations, 2011 CFR

2011-10-01

... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...

47 CFR 73.3521 - Mutually exclusive applications for low power television, television translators and television...

Code of Federal Regulations, 2014 CFR

2014-10-01

... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...

47 CFR 73.3521 - Mutually exclusive applications for low power television, television translators and television...

Code of Federal Regulations, 2010 CFR

2010-10-01

... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...

The magic of image processing

NASA Astrophysics Data System (ADS)

Sulentic, Jack W.; Lorre, Jean J.

1984-05-01

Digital technology has been used to improve enhancement techniques in astronomical image processing. Continuous tone variations in photographs are assigned density number (DN) values which are arranged in an array. DN locations are processed by computer and turned into pixels which form a reconstruction of the original scene on a television monitor. Digitized data can be manipulated to enhance contrast and filter out gross patterns of light and dark which obscure small scale features. Separate black and white frames exposed at different wavelengths can be digitized and processed individually, then recombined to produce a final image in color. Several examples of the use of the technique are provided, including photographs of spiral galaxy M33; four galaxies in Coma Berenices (NGC 4169, 4173, 4174, and 4175); and Stephens Quintet.

Applied photo interpretation for airbrush cartography

NASA Technical Reports Server (NTRS)

Inge, J. L.; Bridges, P. M.

1976-01-01

New techniques of cartographic portrayal have been developed for the compilation of maps of lunar and planetary surfaces. Conventional photo interpretation methods utilizing size, shape, shadow, tone, pattern, and texture are applied to computer processed satellite television images. The variety of the image data allows the illustrator to interpret image details by inter-comparison and intra-comparison of photographs. Comparative judgements are affected by illumination, resolution, variations in surface coloration, and transmission or processing artifacts. The validity of the interpretation process is tested by making a representational drawing by an airbrush portrayal technique. Production controls insure the consistency of a map series. Photo interpretive cartographic portrayal skills are used to prepare two kinds of map series and are adaptable to map products of different kinds and purposes.

Mars atmospheric opacity effects observed in the Northern Hemisphere by Viking orbiter imaging

NASA Technical Reports Server (NTRS)

Thorpe, T. E.

1981-01-01

Viking orbiter television camera observations of Mars contrasts show variations of atmospheric opacity in the Southern Hemisphere. The study is extended into the Northern Hemisphere, over a longer time period, and results in a detailed description of photometric changes at the lander sites, as seen from orbit. During the period of January 1977 to April 1978, a series of four storms at 202 deg, 264 deg, 40 deg and 86 deg latitudes have provided photometric changes and planetwide aerosol distributions for 18 months. It is found that the large, forward-scattering particles did not enter the atmosphere at the storm's onsets. A reduction of atmospheric transmission by over 20% at visual wavelengths remained for nearly one Martian year.

Correction of aeroheating-induced intensity nonuniformity in infrared images

NASA Astrophysics Data System (ADS)

Liu, Li; Yan, Luxin; Zhao, Hui; Dai, Xiaobing; Zhang, Tianxu

2016-05-01

Aeroheating-induced intensity nonuniformity effects severely influence the effective performance of an infrared (IR) imaging system in high-speed flight. In this paper, we propose a new approach to the correction of intensity nonuniformity in IR images. The basic assumption is that the low-frequency intensity bias is additive and smoothly varying so that it can be modeled as a bivariate polynomial and estimated by using an isotropic total variation (TV) model. A half quadratic penalty method is applied to the isotropic form of TV discretization. And an alternating minimization algorithm is adopted for solving the optimization model. The experimental results of simulated and real aerothermal images show that the proposed correction method can effectively improve IR image quality.

Variable features on Mars - Preliminary Mariner 9 television results.

NASA Technical Reports Server (NTRS)

Sagan, C.; Veverka, J.; Fox, P.; Dubisch, R.; Lederberg, J.; Levinthal, E.; Quam, L.; Tucker, R.; Pollack, J. B.; Smith, B. A.

1972-01-01

Systematic Mariner 9 photography of a range of Martian surface features, observed with all three photometric angles approximately invariant, reveals three general categories of albedo variations: (1) an essentially uniform contrast enhancement due to the dissipation of the dust storm; (2) the appearance of splotches, irregular dark markings at least partially related to topography; and (3) the development of both bright and dark linear streaks, generally emanating from craters. Some splotches and streaks vary on characteristic timescales of about two weeks; they have characteristic dimensions of kilometers to tens of kilometers. The morphology and variability of streaks and splotches, and the resolution of at least one splotch into an extensive dune system, implicate windblown dust as the principal agent of Martian albedo differences and variability.

CNV-TV: a robust method to discover copy number variation from short sequencing reads.

PubMed

Duan, Junbo; Zhang, Ji-Gang; Deng, Hong-Wen; Wang, Yu-Ping

2013-05-02

Copy number variation (CNV) is an important structural variation (SV) in human genome. Various studies have shown that CNVs are associated with complex diseases. Traditional CNV detection methods such as fluorescence in situ hybridization (FISH) and array comparative genomic hybridization (aCGH) suffer from low resolution. The next generation sequencing (NGS) technique promises a higher resolution detection of CNVs and several methods were recently proposed for realizing such a promise. However, the performances of these methods are not robust under some conditions, e.g., some of them may fail to detect CNVs of short sizes. There has been a strong demand for reliable detection of CNVs from high resolution NGS data. A novel and robust method to detect CNV from short sequencing reads is proposed in this study. The detection of CNV is modeled as a change-point detection from the read depth (RD) signal derived from the NGS, which is fitted with a total variation (TV) penalized least squares model. The performance (e.g., sensitivity and specificity) of the proposed approach are evaluated by comparison with several recently published methods on both simulated and real data from the 1000 Genomes Project. The experimental results showed that both the true positive rate and false positive rate of the proposed detection method do not change significantly for CNVs with different copy numbers and lengthes, when compared with several existing methods. Therefore, our proposed approach results in a more reliable detection of CNVs than the existing methods.

76 FR 11680 - Digital Low Power Television, Television Translator, and Television Booster Stations and Digital...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-03

...] Digital Low Power Television, Television Translator, and Television Booster Stations and Digital Class A... Commission's Rules to Establish Rules for Digital Low Power, Television Translator, and Television Booster... Digital Low Power Television Translator, Television Booster Stations, and to Amend Rules for Digital Class...

MO-FG-CAMPUS-IeP2-04: Multiple Penalties with Different Orders for Structure Adaptive CBCT Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi, Q; Cheng, P; Tan, S

2016-06-15

Purpose: To combine total variation (TV) and Hessian penalty in a structure adaptive way for cone-beam CT (CBCT) reconstruction. Methods: TV is a widely used first order penalty with good ability in suppressing noise and preserving edges but leads to the staircase effect in regions with smooth intensity transition. The second order Hessian penalty can effectively suppress the staircase effect with extra cost of blurring object edges. To take the best of both penalties we proposed a novel method to combine both for CBCT reconstruction in a structure adaptive way. The proposed method adaptively determined the weight of each penaltymore » according to the geometry of local regions. An specially-designed exponent term with image gradient involved was used to characterize the local geometry such that the weights for Hessian and TV were 1 and 0 respectively at uniform local regions and 0 and 1 at edge regions. For other local regions the weights varied from 0 to 1. The objective functional was minimized using the majorzationminimization approach. We evaluated the proposed method on a modified 3D shepp-logan and a CatPhan 600 phantom. The full-width-at-halfmaximum (FWHM) and contrast-to-noise (CNR) were calculated. Results: For 3D shepp-logan the reconstructed images using TV had an obvious staircase effect while those using the proposed method and Hessian preserved the smooth transition regions well. FWHMs of the proposed method TV and Hessian penalty were 1.75 1.61 and 3.16 respectively, indicating that both TV and the proposed method is able to preserve edges. For CatPhan 600 CNR values of the proposed method were similar to those of TV and Hessian. Conclusion: The proposed method retains favorable properties of TV like preserving edges and also has the ability in better preserving gradual transition structure as Hessian does. All methods performs similarly in suppressing noise. This work was supported in part by National Natural Science Foundation of China (NNSFC) under Grant Nos.60971112 and 61375018 grants from the Cancer Prevention and Research Institute of Texas (RP130109 and RP110562-P2) National Institute of Biomedical Imaging and Bioengineering (R01 EB020366) and a grant from the American Cancer Society (RSG-13-326-01-CCE).« less

SU-F-18C-14: Hessian-Based Norm Penalty for Weighted Least-Square CBCT Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, T; Sun, N; Tan, S

Purpose: To develop a Hessian-based norm penalty for cone-beam CT (CBCT) reconstruction that has a similar ability in suppressing noise as the total variation (TV) penalty while avoiding the staircase effect and better preserving low-contrast objects. Methods: We extended the TV penalty to a Hessian-based norm penalty based on the Frobenius norm of the Hessian matrix of an image for CBCT reconstruction. The objective function was constructed using the penalized weighted least-square (PWLS) principle. An effective algorithm was developed to minimize the objective function using a majorization-minimization (MM) approach. We evaluated and compared the proposed penalty with the TV penaltymore » on a CatPhan 600 phantom and an anthropomorphic head phantom, each acquired at a low-dose protocol (10mA/10ms) and a high-dose protocol (80mA/12ms). For both penalties, contrast-to-noise (CNR) in four low-contrast regions-of-interest (ROIs) and the full-width-at-half-maximum (FWHM) of two point-like objects in constructed images were calculated and compared. Results: In the experiment of CatPhan 600 phantom, the Hessian-based norm penalty has slightly higher CNRs and approximately equivalent FWHM values compared with the TV penalty. In the experiment of the anthropomorphic head phantom at the low-dose protocol, the TV penalty result has several artificial piece-wise constant areas known as the staircase effect while in the Hessian-based norm penalty the image appears smoother and more similar to that of the FDK result using the high-dose protocol. Conclusion: The proposed Hessian-based norm penalty has a similar performance in suppressing noise to the TV penalty, but has a potential advantage in suppressing the staircase effect and preserving low-contrast objects. This work was supported in part by National Natural Science Foundation of China (NNSFC), under Grant Nos. 60971112 and 61375018, and Fundamental Research Funds for the Central Universities, under Grant No. 2012QN086.« less

Potential of Proton Therapy to Reduce Acute Hematologic Toxicity in Concurrent Chemoradiation Therapy for Esophageal Cancer.

PubMed

Warren, Samantha; Hurt, Christopher N; Crosby, Thomas; Partridge, Mike; Hawkins, Maria A

2017-11-01

Radiation therapy dose escalation using a simultaneous integrated boost (SIB) is predicted to improve local tumor control in esophageal cancer; however, any increase in acute hematologic toxicity (HT) could limit the predicted improvement in patient outcomes. Proton therapy has been shown to significantly reduce HT in lung cancer patients receiving concurrent chemotherapy. Therefore, we investigated the potential of bone marrow sparing with protons for esophageal tumors. Twenty-one patients with mid-esophageal cancer who had undergone conformal radiation therapy (3D50) were selected. Two surrogates for bone marrow were created by outlining the thoracic bones (bone) and only the body of the thoracic vertebrae (TV) in Eclipse. The percentage of overlap of the TV with the planning treatment volume was recorded for each patient. Additional plans were created retrospectively, including a volumetric modulated arc therapy (VMAT) plan with the same dose as for 3D50; a VMAT SIB plan with a dose prescription of 62.5 Gy to the high-risk subregion within the planning treatment volume; a reoptimized TV-sparing VMAT plan; and a proton therapy plan with the same SIB dose prescription. The bone and TV dose metrics were recorded and compared across all plans and variations with respect to PTV and percentage of overlap for each patient. The 3D50 plans showed the highest bone mean dose and TV percentage of volume receiving ≥30 Gy (V 30Gy ) for each patient. The VMAT plans irradiated a larger bone V 10Gy than did the 3D50 plans. The reoptimized VMAT62.5 VT plans showed improved sparing of the TV volume, but only the proton plans showed significant sparing for bone V 10Gy and bone mean dose, especially for patients with a larger PTV. The results of the present study have shown that proton therapy can reduced bone marrow toxicity. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Geostatistics as a tool to improve the natural background level definition: An application in groundwater.

PubMed

Dalla Libera, Nico; Fabbri, Paolo; Mason, Leonardo; Piccinini, Leonardo; Pola, Marco

2017-11-15

The Natural Background Level (NBL), suggested by UE BRIDGE project, is suited for spatially distributed datasets providing a regional value that could be higher than the Threshold Value (TV) set by every country. In hydro-geochemically dis-homogeneous areas, the use of a unique regional NBL, higher than TV, could arise problems to distinguish between natural occurrences and anthropogenic contaminant sources. Hence, the goal of this study is to improve the NBL definition employing a geostatistical approach, which reconstructs the contaminant spatial structure accounting geochemical and hydrogeological relationships. This integrated mapping is fundamental to evaluate the contaminant's distribution impact on the NBL, giving indications to improve it. We decided to test this method on the Drainage Basin of Venice Lagoon (DBVL, NE Italy), where the existing NBL is seven times higher than the TV. This area is notoriously affected by naturally occurring arsenic contamination. An available geochemical dataset collected by 50 piezometers was used to reconstruct the spatial distribution of arsenic in the densely populated area of the DBVL. A cokriging approach was applied exploiting the geochemical relationships among As, Fe and NH4+. The obtained spatial predictions of arsenic concentrations were divided into three different zones: i) areas with an As concentration lower than the TV, ii) areas with an As concentration between the TV and the median of the values higher than the TV, and iii) areas with an As concentration higher than the median. Following the BRIDGE suggestions, where enough samples were available, the 90th percentile for each zone was calculated to obtain a local NBL (LNBL). Differently from the original NBL, this local value gives more detailed water quality information accounting the hydrogeological and geochemical setting, and contaminant spatial variation. Hence, the LNBL could give more indications about the distinction between natural occurrence and anthropogenic contamination. Copyright © 2017 Elsevier B.V. All rights reserved.

Theoretical Research at the High Energy Frontier: Cosmology, Neutrinos, and Beyond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krauss, Lawrence M; Vachaspati, Tanmay; Parikh, Maulik

The DOE theory group grew from 2009-2012 from a single investigator, Lawrence Krauss, the PI on the grant, to include 3 faculty (with the addition of Maulik Parikh and Tanmay Vachaspati), and a postdoc covered by the grant, as well as partial support for a graduate student. The group has explored issues ranging from gravity and quantum field theory to topological defects, energy conditions in general relativity, primordial magnetic fields, neutrino astrophysics, quantum phases, gravitational waves from the early universe, dark matter detection schemes, signatures for dark matter at the LHC, and indirect astrophysical signatures for dark matter. In addition,more » we have run active international workshops each year, as well as a regular visitor program. As well, the PI's outreach activities, including popular books and articles, and columns for newspapers and magazines, as well as television and radio appearances have helped raise the profile of high energy physics internationally. The postdocs supported by the grant, James Dent and Roman Buniy have moved on successfully to a faculty positions in Louisiana and California.« less

Bet Anywhere, Anytime: An Analysis of Internet Sports Bettors' Responses to Gambling Promotions During Sports Broadcasts by Problem Gambling Severity.

PubMed

Hing, Nerilee; Russell, Alex Myles Thomas; Lamont, Matthew; Vitartas, Peter

2017-12-01

Promotions for online sports betting during televised sports broadcasts are regularly viewed by millions of Australians, raising concerns about their impacts on vulnerable groups including at-risk and problem gamblers. This study examined whether responses to these promotions varied with problem gambling severity amongst 455 Australian Internet sports bettors participating in an online survey. Results indicated that young male Internet sports bettors are especially vulnerable to gambling problems, particularly if they hold positive attitudes to gambling sponsors who embed promotions into sports broadcasts and to the promotional techniques they use and this heightens the risk that alluring messages contribute to excessive gambling. As problem gambling severity increased, so too did recognition that these promotions have impacted negatively on their sports betting behaviour. Because a plethora of sports betting brands and promotions are now heavily integrated into sports coverage, social marketing efforts are needed to offset their persuasive appeal and counter the positive attitudes towards them that appear linked to excessive gambling amongst Internet sports bettors.

Heritability of Lumbar Trabecular Bone Mechanical Properties in Baboons

PubMed Central

Havill, L.M.; Allen, M.R.; Bredbenner, T.L.; Burr, D.B.; Nicolella, D.P.; Turner, C.H.; Warren, D.M.; Mahaney, M.C.

2010-01-01

Genetic effects on mechanical properties have been demonstrated in rodents, but not confirmed in primates. Our aim was to quantify the proportion of variation in vertebral trabecular bone mechanical properties that is due to the effects of genes. L3 vertebrae were collected from 110 females and 46 male baboons (6–32 years old) from a single extended pedigree. Cranio-caudally oriented trabecular bone cores were scanned with microCT then tested in monotonic compression to determine apparent ultimate stress, modulus, and toughness. Age and sex effects and heritability (h2) were assessed using maximum likelihood-based variance components methods. Additive effects of genes on residual trait variance were significant for ultimate stress (h2=0.58), toughness (h2=0.64), and BV/TV (h2=0.55). When BV/TV was accounted for, the residual variance in ultimate stress accounted for by the additive effects of genes was no longer significant. Toughness, however, showed evidence of a non-BV/TV-related genetic effect. Overall, maximum stress and modulus show strong genetic effects that are nearly entirely due to bone volume. Toughness shows strong genetic effects related to bone volume and shows additional genetic effects (accounting for 10% of the total trait variance) that are independent of bone volume. These results support continued use of bone volume as a focal trait to identify genes related to skeletal fragility, but also show that other focal traits related to toughness and variation in the organic component of bone matrix will enhance our ability to find additional genes that are particularly relevant to fatigue-related fractures. PMID:19900599

Analysis of the Tikhonov regularization to retrieve thermal conductivity depth-profiles from infrared thermography data

NASA Astrophysics Data System (ADS)

Apiñaniz, Estibaliz; Mendioroz, Arantza; Salazar, Agustín; Celorrio, Ricardo

2010-09-01

We analyze the ability of the Tikhonov regularization to retrieve different shapes of in-depth thermal conductivity profiles, usually encountered in hardened materials, from surface temperature data. Exponential, oscillating, and sigmoidal profiles are studied. By performing theoretical experiments with added white noises, the influence of the order of the Tikhonov functional and of the parameters that need to be tuned to carry out the inversion are investigated. The analysis shows that the Tikhonov regularization is very well suited to reconstruct smooth profiles but fails when the conductivity exhibits steep slopes. We check a natural alternative regularization, the total variation functional, which gives much better results for sigmoidal profiles. Accordingly, a strategy to deal with real data is proposed in which we introduce this total variation regularization. This regularization is applied to the inversion of real data corresponding to a case hardened AISI1018 steel plate, giving much better anticorrelation of the retrieved conductivity with microindentation test data than the Tikhonov regularization. The results suggest that this is a promising way to improve the reliability of local inversion methods.

An evaluation of a mass media campaign to encourage parents of adolescents to talk to their children about sex.

PubMed

DuRant, Robert H; Wolfson, Mark; LaFrance, Betty; Balkrishnan, Rajesh; Altman, David

2006-03-01

We evaluated a mass media campaign in North Carolina that used television (TV) public service announcements (PSAs), radio PSAs, and billboards to encourage parents of adolescents to talk to their children about sex. The primary message of the campaign was "Talk to your kids about sex. Everyone else is." Thirty-two of the 100 counties in North Carolina were chosen to evaluate the mass media campaign. Paid TV PSAs were aired in 22 of these counties, radio PSAs were aired in 21 counties, and billboards were displayed in 6 counties over a period of 9 months. The counties in our sample varied from no exposure to exposure to all 3 types of media. To assess the impact of the campaign, a sample of 1,132 parents of adolescents living in the 32 counties was administered a postexposure survey via a telephone interview. Questions about exposure to the media campaign were embedded among questions concerning media exposure to other health-related messages. The parent survey assessed the frequency the parents reported exposure to each type of media message, correct knowledge of the message, and multiple item scales that assessed how often they had talked to their child about various issues related to sex during the previous 6 months, intentions to talk to their child about these issues during the next month, and attitudes about discussing sexual issues with their child. In bivariate analyses the levels of parental exposure to the 3 types of media messages were associated with both having talked to their children and intentions to talk to their children about sex (p < .0001). When analyzed with multiple regression, female gender, minority ethnicity, frequency of seeing a billboard on teenage pregnancy, frequency of seeing a TV PSA about sex, and frequency of hearing a radio PSA about sex and teenage pregnancy accounted for 12.8% (p < .0001) of the variance in having talked to their child about sex. Female gender, minority ethnicity, and previously talking to their child about sex accounted for 9.9% of the variation in positive communication attitudes about sex. Positive communication attitudes, female parent, minority ethnicity, frequency of seeing a billboard about sex, frequency of seeing a TV PSA about sex, and frequency of hearing radio PSAs about sex accounted for 12.3% of the variation in parental intentions to talk to their child about sex during the next month. Exposure to each component of this mass media campaign was associated with parents recently having talked to their adolescent children about sex and intentions to talk to their children during the next month.

Composite SAR imaging using sequential joint sparsity

NASA Astrophysics Data System (ADS)

Sanders, Toby; Gelb, Anne; Platte, Rodrigo B.

2017-06-01

This paper investigates accurate and efficient ℓ1 regularization methods for generating synthetic aperture radar (SAR) images. Although ℓ1 regularization algorithms are already employed in SAR imaging, practical and efficient implementation in terms of real time imaging remain a challenge. Here we demonstrate that fast numerical operators can be used to robustly implement ℓ1 regularization methods that are as or more efficient than traditional approaches such as back projection, while providing superior image quality. In particular, we develop a sequential joint sparsity model for composite SAR imaging which naturally combines the joint sparsity methodology with composite SAR. Our technique, which can be implemented using standard, fractional, or higher order total variation regularization, is able to reduce the effects of speckle and other noisy artifacts with little additional computational cost. Finally we show that generalizing total variation regularization to non-integer and higher orders provides improved flexibility and robustness for SAR imaging.

Acquiring variation in an artificial language: Children and adults are sensitive to socially conditioned linguistic variation.

PubMed

Samara, Anna; Smith, Kenny; Brown, Helen; Wonnacott, Elizabeth

2017-05-01

Languages exhibit sociolinguistic variation, such that adult native speakers condition the usage of linguistic variants on social context, gender, and ethnicity, among other cues. While the existence of this kind of socially conditioned variation is well-established, less is known about how it is acquired. Studies of naturalistic language use by children provide various examples where children's production of sociolinguistic variants appears to be conditioned on similar factors to adults' production, but it is difficult to determine whether this reflects knowledge of sociolinguistic conditioning or systematic differences in the input to children from different social groups. Furthermore, artificial language learning experiments have shown that children have a tendency to eliminate variation, a process which could potentially work against their acquisition of sociolinguistic variation. The current study used a semi-artificial language learning paradigm to investigate learning of the sociolinguistic cue of speaker identity in 6-year-olds and adults. Participants were trained and tested on an artificial language where nouns were obligatorily followed by one of two meaningless particles and were produced by one of two speakers (one male, one female). Particle usage was conditioned deterministically on speaker identity (Experiment 1), probabilistically (Experiment 2), or not at all (Experiment 3). Participants were given tests of production and comprehension. In Experiments 1 and 2, both children and adults successfully acquired the speaker identity cue, although the effect was stronger for adults and in Experiment 1. In addition, in all three experiments, there was evidence of regularization in participants' productions, although the type of regularization differed with age: children showed regularization by boosting the frequency of one particle at the expense of the other, while adults regularized by conditioning particle usage on lexical items. Overall, results demonstrate that children and adults are sensitive to speaker identity cues, an ability which is fundamental to tracking sociolinguistic variation, and that children's well-established tendency to regularize does not prevent them from learning sociolinguistically conditioned variation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... power television and television translator stations. 74.789 Section 74.789 Telecommunication FEDERAL... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.789 Broadcast regulations applicable to digital low power television and television translator...

Factors influencing the television viewing practices of Indian children.

PubMed

Ravikiran, S R; Baliga, B Shantharam; Jain, Animesh; Kotian, M Shashidhar

2014-02-01

To study the effect of socio-demographic factors, parental regulations and maternal television usage on the television viewing practices of Indian schoolchildren. Mothers of 6-12 y old children were interviewed using a pre-tested questionnaire at the pediatric outpatient. The television viewing practices of 405 schoolchildren with maternal television viewing and parental television rules were analyzed. Specific television viewing practices considered harmful in the present study were- viewing television >2 h, viewing television just prior to sleep (at bedtime), predominantly viewing general adult channels and using television as an aid to sleep. 35.8 % (n = 145) of the children viewed television for >2 h on schooldays. 20 % (n = 81) used television as sleep-aid. 28.1 % (n = 114) children had televisions in the room they slept. The frequency of parental television rules were with respect to: duration of viewing- 77.5 % (n = 314), timing of viewing- 63.7 % (n = 258), content- 35.6 % (n = 144). The children of families with the rule needing of parental permission to switch on the television [present in 34.8 % (n = 141) children] had lower harmful television viewing practices: duration of television viewing on schooldays >2 h (23.4 %, n = 33, P < 0.001); television viewed just before sleep (39 %, n = 55, P < 0.001); use of television as sleep-aid (12.1 %, n = 17, P = 0.003). 26.7 % (n = 108) of the mothers viewed television for >2 h. Linear regression analysis showed association between average television duration of children and average maternal television duration on schooldays (Beta = 0.246, t = 5.09, P < 0.001). Binary logistic regression analysis showed that harmful television viewing practices were significantly more in children with television in bedroom [OR = 7.49(4.19-13.38), P < 0.001]. It was reduced significantly by the parental rules on content viewed [OR = 0.41(0.23-0.72), P = 0.002]; need of permission to switch on television [OR = 0.31(0.18-0.53), P < 0.001] and a higher maternal education [OR = 0.29 (0.14-0.59), P = 0.001]. Lower maternal education, increased maternal television usage, presence of television in bedroom resulted in harmful television viewing practices among Indian children. The parental rules that were effective in countering these were the rule on content viewed and needing parental permission to switch on television.

The Radial Variation of the Solar Wind Temperature-Speed Relationship

NASA Astrophysics Data System (ADS)

Elliott, H. A.; McComas, D. J.

2010-12-01

Generally, the solar wind temperature (T) and speed (V) are well correlated except in Interplanetary Coronal Mass Ejections where this correlation breaks down. We have shown that at 1 AU the speed-temperature relationship is often well represented by a linear fit for a speed range spanning both the slow and fast wind. By examining all of the ACE and OMNI measurements, we found that when coronal holes are large the fast wind can have a different T-V relationship than the slow wind. The best example of this was in 2003 when there was a very large and long-lived outward polarity coronal hole at low latitudes. The long-lived nature of the hole made it possible to clearly distinguish that large holes can have a different T-V relationship. We found it to be rare that holes are large enough and last long enough to have enough data points to clearly demonstrate this effect. In this study we compare the 2003 coronal hole observations from ACE with the Ulysses polar coronal hole measurements. In an even earlier ACE study we found that both the compressions and rarefactions curves are linear, but the compression curve is shifted to higher temperatures. In this presentation we use Helios, Ulysses, and ACE measurements to examine how the T-V relationship varies with distance. The dynamic evolution of the solar wind parameters is revealed when we first separate compressions and rarefactions and then determine the radial profiles of the solar wind parameters. We find that T-V relationship varies with distance and in particular beyond 3 AU the differences between the compressions and rarefactions are quite important and at such distances a simple linear fit does not represent the T-V distribution very well.

Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy

NASA Astrophysics Data System (ADS)

Bian, Junguo; Sharp, Gregory C.; Park, Yang-Kyun; Ouyang, Jinsong; Bortfeld, Thomas; El Fakhri, Georges

2016-05-01

It is well-known that projections acquired over an angular range slightly over 180° (so-called short scan) are sufficient for fan-beam reconstruction. However, due to practical imaging conditions (projection data and reconstruction image discretization, physical factors, and data noise), the short-scan reconstructions may have different appearances and properties from the full-scan (scans over 360°) reconstructions. Nevertheless, short-scan configurations have been used in applications such as cone-beam CT (CBCT) for head-neck-cancer image-guided radiation therapy (IGRT) that only requires a small field of view due to the potential reduced imaging time and dose. In this work, we studied the image quality trade-off for full, short, and full/short scan configurations with both conventional filtered-backprojection (FBP) reconstruction and iterative reconstruction algorithms based on total-variation (TV) minimization for head-neck-cancer IGRT. Anthropomorphic and Catphan phantoms were scanned at different exposure levels with a clinical scanner used in IGRT. Both visualization- and numerical-metric-based evaluation studies were performed. The results indicate that the optimal exposure level and number of views are in the middle range for both FBP and TV-based iterative algorithms and the optimization is object-dependent and task-dependent. The optimal view numbers decrease with the total exposure levels for both FBP and TV-based algorithms. The results also indicate there are slight differences between FBP and TV-based iterative algorithms for the image quality trade-off: FBP seems to be more in favor of larger number of views while the TV-based algorithm is more robust to different data conditions (number of views and exposure levels) than the FBP algorithm. The studies can provide a general guideline for image-quality optimization for CBCT used in IGRT and other applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, L; Han, Y; Jin, M

Purpose: To develop an iterative reconstruction method for X-ray CT, in which the reconstruction can quickly converge to the desired solution with much reduced projection views. Methods: The reconstruction is formulated as a convex feasibility problem, i.e. the solution is an intersection of three convex sets: 1) data fidelity (DF) set – the L2 norm of the difference of observed projections and those from the reconstructed image is no greater than an error bound; 2) non-negativity of image voxels (NN) set; and 3) piecewise constant (PC) set - the total variation (TV) of the reconstructed image is no greater thanmore » an upper bound. The solution can be found by applying projection onto convex sets (POCS) sequentially for these three convex sets. Specifically, the algebraic reconstruction technique and setting negative voxels as zero are used for projection onto the DF and NN sets, respectively, while the projection onto the PC set is achieved by solving a standard Rudin, Osher, and Fatemi (ROF) model. The proposed method is named as full sequential POCS (FS-POCS), which is tested using the Shepp-Logan phantom and the Catphan600 phantom and compared with two similar algorithms, TV-POCS and CP-TV. Results: Using the Shepp-Logan phantom, the root mean square error (RMSE) of reconstructed images changing along with the number of iterations is used as the convergence measurement. In general, FS- POCS converges faster than TV-POCS and CP-TV, especially with fewer projection views. FS-POCS can also achieve accurate reconstruction of cone-beam CT of the Catphan600 phantom using only 54 views, comparable to that of FDK using 364 views. Conclusion: We developed an efficient iterative reconstruction for sparse-view CT using full sequential POCS. The simulation and physical phantom data demonstrated the computational efficiency and effectiveness of FS-POCS.« less

Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy.

PubMed

Bian, Junguo; Sharp, Gregory C; Park, Yang-Kyun; Ouyang, Jinsong; Bortfeld, Thomas; El Fakhri, Georges

2016-05-07

It is well-known that projections acquired over an angular range slightly over 180° (so-called short scan) are sufficient for fan-beam reconstruction. However, due to practical imaging conditions (projection data and reconstruction image discretization, physical factors, and data noise), the short-scan reconstructions may have different appearances and properties from the full-scan (scans over 360°) reconstructions. Nevertheless, short-scan configurations have been used in applications such as cone-beam CT (CBCT) for head-neck-cancer image-guided radiation therapy (IGRT) that only requires a small field of view due to the potential reduced imaging time and dose. In this work, we studied the image quality trade-off for full, short, and full/short scan configurations with both conventional filtered-backprojection (FBP) reconstruction and iterative reconstruction algorithms based on total-variation (TV) minimization for head-neck-cancer IGRT. Anthropomorphic and Catphan phantoms were scanned at different exposure levels with a clinical scanner used in IGRT. Both visualization- and numerical-metric-based evaluation studies were performed. The results indicate that the optimal exposure level and number of views are in the middle range for both FBP and TV-based iterative algorithms and the optimization is object-dependent and task-dependent. The optimal view numbers decrease with the total exposure levels for both FBP and TV-based algorithms. The results also indicate there are slight differences between FBP and TV-based iterative algorithms for the image quality trade-off: FBP seems to be more in favor of larger number of views while the TV-based algorithm is more robust to different data conditions (number of views and exposure levels) than the FBP algorithm. The studies can provide a general guideline for image-quality optimization for CBCT used in IGRT and other applications.

The Impact of the Newer Television Technologies on Television Satisfaction.

ERIC Educational Resources Information Center

Perse, Elizabeth M.; Ferguson, Douglas A.

1993-01-01

Finds that use of new television technologies (cable television, videocassette recorders, and remote control devices) had an impact on receiving, pass-the-time, and companionship gratifications from television viewing. Shows that instrumental viewing motives, television exposure, and receiving informational gratifications from television viewing…

ILLINOIS JOURNAL OF EDUCATION--ILLINOIS SCHOOLS AND EDUCATIONAL TELEVISION.

ERIC Educational Resources Information Center

PAGE, RAY

THIS PUBLICATION CONTAINS THIRTEEN ARTICLES ON THE USE OF EDUCATIONAL TELEVISION IN ILLINOIS. AMONG THE TOPICS COVERED ARE MULTICHANNEL MICROWAVE EDUCATIONAL TELEVISION, INNOVATIVE TELEVISION, OPEN- AND CLOSED-CIRCUIT TELEVISON, TELEVISION IN PSYCHOLOGY, AND STATE EDUCATIONAL TELEVISION LEGISLATION. THE USE OF THE TELEVISION MEDIUM IN VARIOUS…

Television the Medium, the Message and Nutritional Health.

ERIC Educational Resources Information Center

Wadsworth, Laurie A.

1996-01-01

Presents a review of research linking nutritional health and body image attitudes with television viewing. Highlights include content analyses of advertisements and programming; audience uses of television; television as reality; socialization of attitudes and television; television, body image and self-esteem; television and health behaviors; and…

76 FR 46292 - Information Collections Being Reviewed by the Federal Communications Commission

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-02

... Translator, and Television Booster Stations and to Amend Rules for Digital Class A Television Stations, MB... digital broadcasting and states that low power television, TV translator, and Class A television stations... Television, TV Translator and Class A Television Digital Transition Notifications; FCC Form 337. Form Number...

75 FR 64729 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-20

... Rules to Establish Rules for Digital Low Power Television Translator, Television Booster Stations, and... power television (``LPTV'') and television translator (``TV translator'') stations and modifies certain... to this collection (namely, ``low power television, TV translator, and Class A television station DTV...

A fractional-N PLL with small ΔK vco wideband LC-VCO and current-matching CP for M-DTV systems

NASA Astrophysics Data System (ADS)

Gao, Haijun; Yan, Yuepeng; Du, Zhankun; Guo, Guiliang; Zeng, Longyue

2011-06-01

An Σ-Δ fractional-N frequency synthesiser with small K vco-variation wideband LC voltage controlled oscillator (LC-VCO) and current-matching charge pump (CP) for Mobile Digital television Systems is presented. To achieve small VCO-gain (K vco) variation, a parallel switched varactor array is proposed to the conventional wideband LC-VCO with switched capacitor array, the value of the switched varactor is pre-set and both arrays are controlled by the same switching code. Perfect current matching and good stability are obtained by the improved CP with an added bias branch circuit for low reference spur. The chip was fabricated in a Taiwan Semiconductor Manufacturing Company (TSMC) 0.25 µm complementary metal-oxide-semiconductor process and draws 12 mA from a 2.5 V supply voltage. The synthesiser covers a wide tuning range from 0.82 to 1.85 GHz with two integrated LC-VCOs, and each VCO achieves a K vco variation of less than 16% with a tuning range of more than 46%. The current mismatch of CP is as low as 1.2%. The measured close-in and out-of-band phase noise are -83.5 dBc/Hz@10 kHz and -127 dBc/Hz@1 MHz, respectively, the reference spur is -76.3 dBc.

76 FR 44821 - Digital Low Power Television, Television Translator, and Television Booster Stations and To Amend...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-27

...] Digital Low Power Television, Television Translator, and Television Booster Stations and To Amend Rules... this proceeding in order to allow a timely and successful completion of the low power television digital transition. Although Congress established a hard deadline of June 12, 2009 for full power stations...

Relationship between parental estimate and an objective measure of child television watching

PubMed Central

Robinson, Jodie L; Winiewicz, Dana D; Fuerch, Janene H; Roemmich, James N; Epstein, Leonard H

2006-01-01

Many young children have televisions in their bedrooms, which may influence the relationship between parental estimate and objective measures of child television usage/week. Parental estimates of child television time of eighty 4–7 year old children (6.0 ± 1.2 years) at the 75th BMI percentile or greater (90.8 ± 6.8 BMI percentile) were compared to an objective measure of television time obtained from TV Allowance™ devices attached to every television in the home over a three week period. Results showed that parents overestimate their child's television time compared to an objective measure when no television is present in the bedroom by 4 hours/week (25.4 ± 11.5 vs. 21.4 ± 9.1) in comparison to underestimating television time by over 3 hours/week (26.5 ± 17.2 vs. 29.8 ± 14.4) when the child has a television in their bedroom (p = 0.02). Children with a television in their bedroom spend more objectively measured hours in television time than children without a television in their bedroom (29.8 ± 14.2 versus 21.4 ± 9.1, p = 0.003). Research on child television watching should take into account television watching in bedrooms, since it may not be adequately assessed by parental estimates. PMID:17129381

47 CFR 73.6019 - Digital Class A TV station protection of low power TV, TV translator, digital low power TV and...

Code of Federal Regulations, 2010 CFR

2010-10-01

... power TV, TV translator, digital low power TV and digital TV translator stations. 73.6019 Section 73... low power TV, TV translator, digital low power TV and digital TV translator stations. An application... A TV station will not be accepted if it fails to protect authorized low power TV, TV translator...

47 CFR 73.3572 - Processing of TV broadcast, Class A TV broadcast, low power TV, TV translators, and TV booster...

Code of Federal Regulations, 2010 CFR

2010-10-01

... broadcast, low power TV, TV translators, and TV booster applications. 73.3572 Section 73.3572..., low power TV, TV translators, and TV booster applications. (a) Applications for TV stations are..., TV translator, and TV booster stations authorized under part 74 of this chapter, a major change is...

Discharge regularity in the turtle posterior crista: comparisons between experiment and theory.

PubMed

Goldberg, Jay M; Holt, Joseph C

2013-12-01

Intra-axonal recordings were made from bouton fibers near their termination in the turtle posterior crista. Spike discharge, miniature excitatory postsynaptic potentials (mEPSPs), and afterhyperpolarizations (AHPs) were monitored during resting activity in both regularly and irregularly discharging units. Quantal size (qsize) and quantal rate (qrate) were estimated by shot-noise theory. Theoretically, the ratio, σV/(dμV/dt), between synaptic noise (σV) and the slope of the mean voltage trajectory (dμV/dt) near threshold crossing should determine discharge regularity. AHPs are deeper and more prolonged in regular units; as a result, dμV/dt is larger, the more regular the discharge. The qsize is larger and qrate smaller in irregular units; these oppositely directed trends lead to little variation in σV with discharge regularity. Of the two variables, dμV/dt is much more influential than the nearly constant σV in determining regularity. Sinusoidal canal-duct indentations at 0.3 Hz led to modulations in spike discharge and synaptic voltage. Gain, the ratio between the amplitudes of the two modulations, and phase leads re indentation of both modulations are larger in irregular units. Gain variations parallel the sensitivity of the postsynaptic spike encoder, the set of conductances that converts synaptic input into spike discharge. Phase variations reflect both synaptic inputs to the encoder and postsynaptic processes. Experimental data were interpreted using a stochastic integrate-and-fire model. Advantages of an irregular discharge include an enhanced encoder gain and the prevention of nonlinear phase locking. Regular and irregular units are more efficient, respectively, in the encoding of low- and high-frequency head rotations, respectively.

Discharge regularity in the turtle posterior crista: comparisons between experiment and theory

PubMed Central

Holt, Joseph C.

2013-01-01

Intra-axonal recordings were made from bouton fibers near their termination in the turtle posterior crista. Spike discharge, miniature excitatory postsynaptic potentials (mEPSPs), and afterhyperpolarizations (AHPs) were monitored during resting activity in both regularly and irregularly discharging units. Quantal size (qsize) and quantal rate (qrate) were estimated by shot-noise theory. Theoretically, the ratio, σV/(dμV/dt), between synaptic noise (σV) and the slope of the mean voltage trajectory (dμV/dt) near threshold crossing should determine discharge regularity. AHPs are deeper and more prolonged in regular units; as a result, dμV/dt is larger, the more regular the discharge. The qsize is larger and qrate smaller in irregular units; these oppositely directed trends lead to little variation in σV with discharge regularity. Of the two variables, dμV/dt is much more influential than the nearly constant σV in determining regularity. Sinusoidal canal-duct indentations at 0.3 Hz led to modulations in spike discharge and synaptic voltage. Gain, the ratio between the amplitudes of the two modulations, and phase leads re indentation of both modulations are larger in irregular units. Gain variations parallel the sensitivity of the postsynaptic spike encoder, the set of conductances that converts synaptic input into spike discharge. Phase variations reflect both synaptic inputs to the encoder and postsynaptic processes. Experimental data were interpreted using a stochastic integrate-and-fire model. Advantages of an irregular discharge include an enhanced encoder gain and the prevention of nonlinear phase locking. Regular and irregular units are more efficient, respectively, in the encoding of low- and high-frequency head rotations, respectively. PMID:24004525

About Television.

ERIC Educational Resources Information Center

Mayer, Martin

The entire broadcast television industry is the subject of this book. An attempt is made to present history, theory, and anecdotes about television programing, television advertising, television and politics, and network news, focusing all the while on American television, but with consideration given to alternative structures and methods.…

The Vicissitudes of "Progressive Television."

ERIC Educational Resources Information Center

Ang, Ien

This document analyzes and evaluates dilemmas and difficulties in developing/implementing "progressive television," a kind of television that seeks to transgress the boundaries of dominant (mainstream) television by proposing a new constellation of television production and consumption. The ideal is described as a television that tries…

Mediators of the relationship between maternal education and children's TV viewing.

PubMed

Hesketh, Kylie; Ball, Kylie; Crawford, David; Campbell, Karen; Salmon, Jo

2007-07-01

Maternal education is consistently found to be inversely related to children's television viewing and is associated with aspects of the family television environment. This study investigates whether family television environment mediates the relationship between maternal education and children's television viewing. Parents of 1484 children reported maternal education, time their child spends watching television, and 21 aspects of the family television environment (potential mediators) during 2002 and 2003. Separate regression analyses were conducted in 2006 for each potential mediator that met two initial conditions for mediation (associated with both maternal education and children's television viewing (p<0.10)), to assess whether inclusion reduced the association between maternal education and children's television viewing. Multivariable regression assessed the combined impact of all mediators. Twelve of 21 potential mediators met the initial conditions for mediation. Inclusion of each resulted in decreased beta values (3.2% to 15.2%) for the association between maternal education and television viewing. Number and placement of televisions in the home appeared to have the greatest mediating effect, followed by frequency of eating dinner in front of the television with the child and rules about television viewing during mealtimes. Together, the 12 mediators accounted for more than one-third of the association between maternal education and children's television viewing time. This study suggests the strong inverse relationship between maternal education and children's television viewing is partly mediated by aspects of the family television environment.

Reliability and validity of a brief questionnaire to assess television viewing and computer use by middle school children.

PubMed

Schmitz, Kathryn H; Harnack, Lisa; Fulton, Janet E; Jacobs, David R; Gao, Shujun; Lytle, Leslie A; Van Coevering, Pam

2004-11-01

Sedentary behaviors, like television viewing, are positively associated with overweight among young people. To monitor national health objectives for sedentary behaviors in young adolescents, this project developed and assessed the reliability and validity of a brief questionnaire to measure weekly television viewing, usual television viewing, and computer use by middle school children. Reliability and validity of the Youth Risk Behavior Survey (YRBS) question on weekday television viewing also were examined. A brief, five-item television and computer use questionnaire was completed twice by 245 middle school children with one week apart. To concurrently assess validity, students also completed television and computer use logs for seven days. Among all students, Spearman correlations for test-retest reliability for television viewing and computer use ranged from 0.55 to 0.68. Spearman correlations between the first questionnaire and the seven-day log produced the following results: YRBS question for weekday television viewing (0.46), weekend television viewing (0.37), average television viewing over the week (0.47), and computer use (0.39). Methods comparison analysis showed a mean difference (hours/week) between answers to questionnaire items and the log of -0.04 (1.70 standard deviation [SD]) hours for weekday television, -0.21 (2.54 SD) for weekend television, -0.09 (1.75 SD) for average television over the week, and 0.68 (1.26 SD) for computer use. The YRBS weekday television viewing question, and the newly developed questions to assess weekend television viewing, average television viewing, and computer use, produced adequate reliability and validity for surveillance of middle school students.

The Future of Educational Television.

ERIC Educational Resources Information Center

Hudson, Robert B.

In order to predict the future of educational television, the author discusses first instructional television, then public television, and also comments on the applications of communications satellites to television in both industrialized and developing nations. He predicts that in the future instructional television will be mainly carried by…

47 CFR 74.792 - Digital low power TV and TV translator station protected contour.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.792 Digital low power TV and TV... interference from other low power TV, TV translator, Class A TV or TV booster stations or digital low power TV...

47 CFR 74.792 - Digital low power TV and TV translator station protected contour.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.792 Digital low power TV and TV... interference from other low power TV, TV translator, Class A TV or TV booster stations or digital low power TV...

47 CFR 74.792 - Digital low power TV and TV translator station protected contour.

Code of Federal Regulations, 2014 CFR

2014-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.792 Digital low power TV and TV... interference from other low power TV, TV translator, Class A TV or TV booster stations or digital low power TV...

47 CFR 74.792 - Digital low power TV and TV translator station protected contour.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.792 Digital low power TV and TV... interference from other low power TV, TV translator, Class A TV or TV booster stations or digital low power TV...

High quality 4D cone-beam CT reconstruction using motion-compensated total variation regularization

NASA Astrophysics Data System (ADS)

Zhang, Hua; Ma, Jianhua; Bian, Zhaoying; Zeng, Dong; Feng, Qianjin; Chen, Wufan

2017-04-01

Four dimensional cone-beam computed tomography (4D-CBCT) has great potential clinical value because of its ability to describe tumor and organ motion. But the challenge in 4D-CBCT reconstruction is the limited number of projections at each phase, which result in a reconstruction full of noise and streak artifacts with the conventional analytical algorithms. To address this problem, in this paper, we propose a motion compensated total variation regularization approach which tries to fully explore the temporal coherence of the spatial structures among the 4D-CBCT phases. In this work, we additionally conduct motion estimation/motion compensation (ME/MC) on the 4D-CBCT volume by using inter-phase deformation vector fields (DVFs). The motion compensated 4D-CBCT volume is then viewed as a pseudo-static sequence, of which the regularization function was imposed on. The regularization used in this work is the 3D spatial total variation minimization combined with 1D temporal total variation minimization. We subsequently construct a cost function for a reconstruction pass, and minimize this cost function using a variable splitting algorithm. Simulation and real patient data were used to evaluate the proposed algorithm. Results show that the introduction of additional temporal correlation along the phase direction can improve the 4D-CBCT image quality.

Expanding the Universe of "Astronomy on Tap" Public Outreach Events

NASA Astrophysics Data System (ADS)

Rice, Emily L.; Levine, Brian; Livermore, Rachael C.; Silverman, Jeffrey M.; LaMassa, Stephanie M.; Tyndall, Amy; Muna, Demitri; Garofali, Kristen; Morris, Brett; Byler, Nell; Fyhrie, Adalyn; Rehnberg, Morgan; Hart, Quyen N.; Connelly, Jennifer L.; Silvia, Devin W.; Morrison, Sarah J.; Agarwal, Bhaskar; Tremblay, Grant; Schwamb, Megan E.

2016-01-01

Astronomy on Tap (AoT, astronomyontap.org) is free public outreach event featuring engaging science presentations in bars, often combined with music, games, and prizes, to encourage a fun, interactive atmosphere. AoT events feature several short astronomy-related presentations primarily by local professional scientists, but also by visiting scientists, students, educators, amatuer astronomers, writers, and artists. Events are held in social venues (bars, coffee shops, art galleries, etc.) in order to bring science directly to the public in a relaxed, informal atmosphere. With this we hope to engage a more diverse audience than typical lectures at academic and cultural institutions and to develop enthusiasm for science among voting, tax-paying adults. The flexible format and content of an AoT event is easy to adapt and expand based on the priorities, resources, and interests of local organizers. The social nature of AoT events provides important professional development and networking opportunities in science communication. Since the first New York City event in April 2013, Astronomy on Tap has expanded to more than ten cities globally, including monthly events in NYC, Austin, Seattle, and Tucson; semi-regular events in Columbus, New Haven, Santiago, Toronto, and Denver; occasional (so far) events in Rochester (NY), Baltimore, Lansing, and Washington, DC; and one-off events in Chicago and Taipei. Several venues regularly attract audiences of over 200 people. We have received media coverage online, in print, and occasionally even on radio and television. In this poster we describe the overarching goals and characteristics of AoT events, distinct adaptations of various locations, resources we have developed, and the methods we use to coordinate among the worldwide local organizers.

Overweight dogs exercise less frequently and for shorter periods: results of a large online survey of dog owners from the UK.

PubMed

German, Alexander J; Blackwell, Emily; Evans, Mark; Westgarth, Carri

2017-01-01

Canine obesity is now the number one health concern in dogs worldwide. Regular physical activity can improve health, and owners are advised to exercise their dogs on a regular basis. However, limited information exists about associations between overweight status of dogs and walking activity. An online survey was conducted between June and August in 2014, coinciding with the broadcast of a national UK television programme, exploring dog behaviour. Information gathered included signalment, overweight status, and owner-reported information on duration and frequency of dog walking. The University of Liverpool Ethics Committee approved the project, and owners consented to data use. Simple and multiple logistic regression analyses were used to determine associations between overweight status and dog walking activity. Data were available from 11 154 adult dogs, and 1801 (16·1 %) of these were reported as overweight by their owners. Dogs reported to be overweight dogs were more likely to be neutered ( P  < 0·0001) and older ( P  < 0·0001). Various breeds were over-represented including beagle, Cavalier King Charles spaniel, golden retriever, Labrador retriever and pug ( P  < 0·0001 for all). Both frequency and duration of walking were negatively associated with overweight status ( P  < 0·0001 for both). On multiple regression analysis, duration and frequency were independently and negatively associated with the odds of being overweight, along with a range of other factors including age, neuter status and breed. This study has identified associations between overweight status and exercise. In the future, studies should determine the reason for this association, and whether changes in walking activity can influence weight status.

Black Television: Avenue of Power

ERIC Educational Resources Information Center

Douglas, Pamela

1973-01-01

Analyzes a few of the prominent issues in black television, examining public television, commercial television, black ownership of stations, cable television, and some projections for the future. (Author/JM)

Health information processing from television: the role of health orientation.

PubMed

Dutta, Mohan J

2007-01-01

The quintessential presence of television in modern American life has led to decades of research on the unhealthy effects of television. However, recent years have witnessed a surge in scholarship seeking to interrogate the positive health effects of television, particularly in the realm of incorporating health content into entertainment-based television programs. One of the important critical questions in the realm of the positive health effects of television focuses on the amount of health information learning contributed by health information content on television. This article takes a motivation-based approach to health information learning from television, arguing that health orientation influences the amount of health information learned by individuals from television. On the basis of 2 separate studies, the article demonstrates that individuals who learn health information from a variety of television programs are more health oriented than individuals who do not learn health information from these television programs.

Mountain Plains Learning Experience Guide: Radio and T.V. Repair. Course: Television Repair.

ERIC Educational Resources Information Center

Arneson, R.; And Others

One of four individualized courses included in a radio and television repair, curriculum, this course focuses on trouble-shooting procedures for both black and white and color television equipment. The course is comprised of ten units: (1) Introduction to/and Block Diagrams of Television, (2) Television Audio Section Troubles, (3) Television Video…

47 CFR 74.707 - Low power TV and TV translator station protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator... low power TV or TV translator stations, or TV booster stations within the following predicted contours... construct a new low power TV, TV translator, or TV booster station or change the facilities of an existing...

47 CFR 74.707 - Low power TV and TV translator station protection.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator... low power TV or TV translator stations, or TV booster stations within the following predicted contours... construct a new low power TV, TV translator, or TV booster station or change the facilities of an existing...

47 CFR 74.707 - Low power TV and TV translator station protection.

Code of Federal Regulations, 2014 CFR

2014-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator... low power TV or TV translator stations, or TV booster stations within the following predicted contours... construct a new low power TV, TV translator, or TV booster station or change the facilities of an existing...

47 CFR 74.707 - Low power TV and TV translator station protection.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator... low power TV or TV translator stations, or TV booster stations within the following predicted contours... construct a new low power TV, TV translator, or TV booster station or change the facilities of an existing...

75 FR 70260 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-17

... Construct or Make Changes in a Low Power TV, TV Translator, or TV Booster Station, FCC Form 346. Form Number... changes in a Low Power Television, TV Translator, or TV Booster broadcast station. On September 9, 2004..., Television Translator, and Television Booster Stations and to Amend Rules for Digital Class A Television...

Reading Meta-Television: A New Model for Reader-Response Criticism.

ERIC Educational Resources Information Center

Olson, Scott R.

Many current models of television viewing regard viewers either as passive receptors, active participants, or addled dupes. A study proposed a more flexible model for television viewing research. The study used the television program "St. Elsewhere," an example of "meta-television" (television programming which contains hidden…

47 CFR 74.798 - Digital television transition notices by broadcasters.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the highest number of viewers is watching. Stations have the discretion as to the form of these... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.798 Digital television transition notices by broadcasters. (a) Each low power television, TV translator and Class A television station...

47 CFR 74.798 - Digital television transition notices by broadcasters.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the highest number of viewers is watching. Stations have the discretion as to the form of these... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.798 Digital television transition notices by broadcasters. (a) Each low power television, TV translator and Class A television station...

47 CFR 74.798 - Digital television transition notices by broadcasters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the highest number of viewers is watching. Stations have the discretion as to the form of these... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.798 Digital television transition notices by broadcasters. (a) Each low power television, TV translator and Class A television station...

47 CFR 74.798 - Digital television transition notices by broadcasters.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the highest number of viewers is watching. Stations have the discretion as to the form of these... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.798 Digital television transition notices by broadcasters. (a) Each low power television, TV translator and Class A television station...

Nielsen Television '73; A Look at the Medium.

ERIC Educational Resources Information Center

Nielsen (A.C.) Co., Chicago, IL.

The latest (1973) edition of Nielsen Television presents data on the television audience. Major findings are graphically summarized and data are presented for: number of stations receivable by household; households equipped with TV sets; United States TV households with color television; total United States households using television by time of…

Television for Deaf People: Selected Projects.

ERIC Educational Resources Information Center

Freebairn, Thomas

Television projects for the deaf are described with special focus on activities by the Deafness Research and Training Center to develop a cable television cooperative to produce and distribute programs for the deaf. The chapter on cable television considers principles of cable television, the model for a cable television cooperative, steps in…

75 FR 81269 - Public Information Collection Requirement Submitted to OMB for Review and Approval, Comments...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-27

... Power Television Translator, Television Booster Stations, and to Amend Rules for Digital Class A... television translator (``TV translator'') stations and modifies certain rules applicable to digital Class A... (namely, ``low power television, TV translator, and Class A television station DTV licensees''). The...

Phase-field modelling of ductile fracture: a variational gradient-extended plasticity-damage theory and its micromorphic regularization

PubMed Central

Teichtmeister, S.; Aldakheel, F.

2016-01-01

This work outlines a novel variational-based theory for the phase-field modelling of ductile fracture in elastic–plastic solids undergoing large strains. The phase-field approach regularizes sharp crack surfaces within a pure continuum setting by a specific gradient damage modelling. It is linked to a formulation of gradient plasticity at finite strains. The framework includes two independent length scales which regularize both the plastic response as well as the crack discontinuities. This ensures that the damage zones of ductile fracture are inside of plastic zones, and guarantees on the computational side a mesh objectivity in post-critical ranges. PMID:27002069

76 FR 5158 - Notice of Public Information Collection(s) Being Submitted for Review and Approval to the Office...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-28

... Authority to Construct or Make Changes in a Low Power TV, TV Translator, or TV Booster Station, FCC Form 346... construct or make changes in a Low Power Television, TV Translator, or TV Booster broadcast station. On..., Television Translator, and Television Booster Stations and to Amend Rules for Digital Class A Television...

Television, video, and computer game usage in children under 11 years of age.

PubMed

Christakis, Dimitri A; Ebel, Beth E; Rivara, Frederick P; Zimmerman, Frederick J

2004-11-01

To conduct a population-based survey of television and other media usage in young children to determine (1) total media usage; (2) the proportion of children who have televisions in their bedrooms and who eat breakfast or dinner in front of the television; and (3) predictors of parental concern about the amount of television their child watches. Telephone survey administered to 1454 parents of children <11 years old derived from a diverse clinic population. The mean age of the index child was 5.05 years. Mean daily reported child media use was as follows: television (1.45 hours; SD, 1.5); videos (1.1 hours; SD, 1.30); and computer games (0.54 hours; SD, 0.96). Thirty percent of parents reported that their child ate breakfast or dinner in front of the television in the past week, and 22% were concerned about the amount of television that their child watched. In multivariate linear regression, eating breakfast or dinner in front of the television in the past week was associated with increased hours of television viewing (0.38 hours [0.21, 0.54]) and video (0.19 hours [0.04, 0.34]). Having a television in a child's bedroom was associated with increased hours of television (0.25 hours [0.07, 0.43]), video viewing (0.31 hours [0.16, 0.47]), and computer games (0.21 hours [0.10, 0.32]). In general, higher parental education was associated with decreased hours of television and video but not computer games. Older children were 2 to 3 times more likely than younger children to have a television in their bedroom and to have eaten a meal in front of it in the past week. More educated parents were less likely to report that their child had a television in their bedroom and more likely to be concerned about the amount of television their child viewed. Combined video and computer game usage exceeded television usage. Both children of low- and high-income parents are at risk for certain behaviors associated with television usage. Parents whose children watched more television were more likely to be concerned about the amount of television their child viewed.

CTV, ITV, ETV, PTV: Television and Education in the 1960s.

ERIC Educational Resources Information Center

Distance Education Report, 2000

2000-01-01

Discusses television in the 1960s as a form of communication including commercial television (CTV), public television (PTV), educational television (ETV), and instructional television (ITV). The Educational Media Study Panel (EMSP), an official advisory group to the Commissioner and the U.S. Office of Education, studied the growth of television…

Inside Television: A Guide To Critical Viewing.

ERIC Educational Resources Information Center

White, Ned

This course is divided into seven units, each focusing on a particular aspect of television. The unit topics and some of the subtopics included are: (1) television and the American viewer; (2) the television industry (the networks, the role of the Federal Communications Commission, public television, and the business of television); (3) programs…

Television Games Preschool Children Play: Patterns, Themes and Uses.

ERIC Educational Resources Information Center

James, Navita Cummings; McCain, Thomas A.

1982-01-01

Analysis of relationship of television content to preschool children's play based on observations at day care center reveals that television is source of content in play; television-facilitated games are not "new"; developmental differences exist in use of television content in play; use of television content in play has positive consequences.…

76 FR 61358 - Information Collections Being Submitted for Review and Approval to the Office of Management and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-04

... Digital Low Power Television Translator, and Television Booster Stations and to Amend Rules for Digital...'') to transition from analog to digital broadcasting and states that low power television, TV translator...; Section 74.788; Low Power Television, TV Translator and Class A Television Digital Transition...

76 FR 23795 - Low-Power Television and Translator Upgrade Program: Notice of Final Closing Date

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-28

.... 110418247-1247-01] Low-Power Television and Translator Upgrade Program: Notice of Final Closing Date AGENCY... receipt of applications for the Low-Power Television and Translator Upgrade Program (Upgrade Program) will... Rules to Establish Rules for Digital Low Power Television, Television Translator, and Television Booster...

76 FR 72704 - Information Collection Approved by the Office of Management and Budget (OMB)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

... 73.3598; CDBS Informal Forms; Section 74.788; Low Power Television, TV Translator and Class A... the Commission's Rules To Establish Rules for Digital Low Power Television Translator, and Television... and states that low *61359 power television, TV translator, and Class A television stations that have...

47 CFR 74.708 - Class A TV and digital Class A TV station protection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.708 Class A TV and digital Class A TV... § 73.6010 of this chapter. (b) An application to construct a new low power TV, TV translator, or TV... prior to the date the low power TV, TV translator, or TV booster application is filed. (c) Applications...

Micro-Computed Tomography Assessment of Fracture Healing: Relationships among Callus Structure, Composition, and Mechanical Function

PubMed Central

Morgan, Elise F.; Mason, Zachary D.; Chien, Karen B.; Pfeiffer, Anthony J.; Barnes, George L.; Einhorn, Thomas A.; Gerstenfeld, Louis C.

2009-01-01

Non-invasive characterization of fracture callus structure and composition may facilitate development of surrogate measures of the regain of mechanical function. As such, quantitative computed tomography- (CT-) based analyses of fracture calluses could enable more reliable clinical assessments of bone healing. Although previous studies have used CT to quantify and predict fracture healing, it is unclear which of the many CT-derived metrics of callus structure and composition are the most predictive of callus mechanical properties. The goal of this study was to identify the changes in fracture callus structure and composition that occur over time and that are most closely related to the regain of mechanical function. Micro-computed tomography (μCT) imaging and torsion testing were performed on murine fracture calluses (n=188) at multiple post-fracture timepoints and under different experimental conditions that alter fracture healing. Total callus volume (TV), mineralized callus volume (BV), callus mineralized volume fraction (BV/TV), bone mineral content (BMC), tissue mineral density (TMD), standard deviation of mineral density (σTMD), effective polar moment of inertia (Jeff), torsional strength, and torsional rigidity were quantified. Multivariate statistical analyses, including multivariate analysis of variance, principal components analysis, and stepwise regression were used to identify differences in callus structure and composition among experimental groups and to determine which of the μCT outcome measures were the strongest predictors of mechanical properties. Although calluses varied greatly in the absolute and relative amounts of mineralized tissue (BV, BMC, and BV/TV), differences among timepoints were most strongly associated with changes in tissue mineral density. Torsional strength and rigidity were dependent on mineral density as well as the amount of mineralized tissue: TMD, BV, and σTMD explained 62% of the variation in torsional strength (p<0.001); and TMD, BMC, BV/TV, and σTMD explained 70% of the variation in torsional rigidity (p<0.001). These results indicate that fracture callus mechanical properties can be predicted by several μCT-derived measures of callus structure and composition. These findings form the basis for developing non-invasive assessments of fracture healing and for identifying biological and biomechanical mechanisms that lead to impaired or enhanced healing. PMID:19013264

TV Violence: What's All the Fuss About?

ERIC Educational Resources Information Center

Singer, Dorothy G.; Singer, Jerome L.

1984-01-01

Discusses problems posed by television violence; how behavioral and social scientists became interested in television violence and its effects on children; how psychologists study relationships between television violence and behavior; how television violence can be counteracted by television industry, parents, and educators; and results from the…

Taking a Look at Television.

ERIC Educational Resources Information Center

King, William, Comp.

1981-01-01

A collection of quotations drawn from research and opinion papers dealing with the impact of television viewing on children. Subtopics addressed are: television viewing statistics, effects of television violence, and the relationship of television to education. (JJD)