Echocardiogram in common (single) ventricle: angiographic-anatomic correlation

Common ventricle is a rare congenital anomaly in which the ventricular chamber receives blood from two separate atrioventricular (A-V) valves or a common A-V valve. Diagnosis of common ventricle was established in 55 patients aged 3 months to 33 years (mean 10 years) at cardiac catheterization in all 55 and at operation or autopsy in 24. In common ventricle with two angiographically demonstrable A-V valves (47 patients), the echocardiographic features included: (1) simultaneous recording (in the same sonic beam with the transducer held stationary) of the echoes of an anterior and a posterior A-V valve without an intervening septal echo (45 of 47 patients); (2) absence, on a base to apex scan, of the ventricular septal echo in the usual position separating the A-V valves (47 of 47 patients); (3) recording, in patients with common ventricle and outflow chamber, of this small outflow chamber anterior to the A-V valves (20 of 23 patients); and (4) recording of echographic continuity of the posterior A-V valve and great artery (27 of 31 patients). In common ventricle with a common A-V valve (8 patients), the echocardiographic features included: (1) a single demonstrable A-V valve, located posteriorly in the ventricle, which showed a large amplitude of excursion during diastole; and (2) absence of a second A-V valve echo or ventricular septal echo. Eight patients were studied postoperatively after surgical correction by ventricular septation. Echographic features included visualization of a prosthetic septum that produced a dense echo and divided the common ventricle into "right" and "left" ventricular chambers. This septum had a large excursion anteriorly during systole. Because common ventricle is now amenable to surgical correction, echocardiography should play an important role in assessment of ventricular anatomy in this complex congenital cardiac defect.     

An effectiveness trial of a selected dissonance-based eating disorder prevention program for female high school students: Long-term effects.

Objective: Efficacy trials found that a dissonance-based eating disorder prevention program in which female high school and college students with body image concerns critique the thin ideal reduced eating disorder risk factors, eating disorder symptoms, and future eating disorder onset. The present effectiveness trial tested whether this program produces effects through long-term follow-up when high school clinicians recruit students and deliver the intervention under real-world conditions. Method: Female high school students with body image concerns (N = 306; M age = 15.7 years, SD = 1.1) were randomized to the dissonance intervention or an educational brochure control condition and completed assessments through 3-year follow-up. Results: Dissonance participants showed significantly greater decreases in body dissatisfaction at 2-year follow-up and eating disorder symptoms at 3-year follow-up than controls; effects on other risk factors, risk for eating disorder onset, and other outcomes (e.g., body mass) were marginal or nonsignificant. Conclusions: Although it was encouraging that some key effects persisted over long-term follow-up, effects were on average smaller in this effectiveness trial than previous efficacy trials, which could be due to (a) facilitator selection, training, and supervision; (b) the lower risk status of participants; or (c) the use of a control condition that produces some effects. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Efficacy trial of a brief cognitive–behavioral depression prevention program for high-risk adolescents: Effects at 1- and 2-year follow-up.

Objective: To evaluate the effects of a brief group cognitive–behavioral (CB) depression prevention program for high-risk adolescents with elevated depressive symptoms at 1- and 2-year follow-up. Method: In this indicated prevention trial, 341 at-risk youths were randomized to a group CB intervention, group supportive expressive intervention, CB bibliotherapy, or educational brochure control condition. Results: Significantly greater reductions in depressive symptoms were shown by group CB participants relative to brochure control participants by 1-year follow-up and bibliotherapy participants by 1- and 2-year follow-up but not relative to supportive expressive participants. Supportive expressive participants showed greater symptom reduction than CB bibliotherapy participants did at 2-year follow-up. Risk for onset of major or minor depression over the 2-year follow-up was significantly lower for group CB participants (14%; odds ratio = 2.2) and CB bibliotherapy participants (3%; odds ratio = 8.1) than for brochure controls (23%). Conclusions: Results indicate that this group CB intervention reduces initial symptoms and risk for future depressive episodes, although both supportive expressive therapy and CB bibliotherapy also produce intervention effects that persist long term. Indeed, CB bibliotherapy emerged as the least expensive method of reducing risk for future episodes of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An economic manufacturing quantity model for a two-stage assembly system with imperfect processes and variable production rate

This article considers a two-stage assembly system with imperfect processes. The former is an automatic stage in which the required components are manufactured. The latter is a manual stage which deals with taking the components to assemble the end product. In addition, the component processes are independent of each other, and the assembly rate is variable. Shortage is allowed, and the unsatisfied demand is completely backlogged. Then, we formulate the proposed problem as a cost minimization model where the assembly rate and the production run time of each component process are decision variables. An algorithm for the computations of the optimal solutions under the constraint of assembly rate is also provided. Finally, a numerical example and sensitivity analysis are carried out to illustrate the model.     

Algorithms for Fuzzy Segmentation

Fuzzy segmentation is an effective way of segmenting out objects in pictures containing both random noise and shading. This is illustrated both on mathematically created pictures and on some obtained from medical imaging. A theory of fuzzy segmentation is presented. To perform fuzzy segmentation, a ‘connectedness map’ needs to be produced. It is demonstrated that greedy algorithms for creating such a connectedness map are faster than the previously used dynamic programming technique. Once the connectedness map is created, segmentation is completed by a simple thresholding of the connectedness map. This approach is efficacious in instances where simple thresholding of the original picture fails. Received: 22 October 1998?Received in revised form: 22 November 1998?Accepted: 2 December 1998     

Optimal Sequential Paging in Cellular Wireless Networks

In a high-capacity cellular network with limited spectral resources, it is desirable to minimize the radio bandwidth costs associated with paging when locating mobile users. Sequential paging, in which cells in the coverage area are partitioned into groups and paged in a non-increasing order of user location probabilities, permits a reduction in the average radio costs of paging at the expense of greater delay in locating the users. We present a polynomial time algorithm for minimizing paging cost under the average delay constraint, a problem that has previously been considered intractable. We show the conditions under which cluster paging, a simple heuristic technique proposed for use with dynamic location update schemes, is optimal. We also present analytical results on the average delay and paging cost obtained with sequential paging, including tight bounds.     

Joint AoA and Channel Estimation for SIMO- OFDM Systems: A Compressive-Sensing Approach

Millimeter-wave (mmWave) transmission has been considered in future fifth generation (5G) communication systems. Since the pathloss in mmWave is severe, beamforming with antenna arrays, an enabling technology in the 5G era, will become a must. To conduct receive beamforming, however, we need to know the information about the angle-of-arrival (AoA). In this paper, we consider joint AoA and channel estimation for single-input-multiple-output (SIMO) OFDM systems. As known, wireless channels are sparse, and this is particularly true for mmWave environments. Conventional compressive-sensing (CS) based channel estimation methods only consider single-input-single-output systems. We propose new matching-pursuit-based CS methods for channel estimation in SIMO-OFDM systems, using frequency-domain pilots. With the estimated channels, AoA’s are then estimated by the maximum-likelihood method. Since a hidden parameter is involved in the problem, an expectation-maximization (EM) algorithm is then employed. The Cramer-Rao lower bound (CRLB) is also derived for the AoA estimation. Simulation results show that the proposed channel estimation can significantly outperform existing methods while the proposed AoA estimation attains the CRLB.     

Heuristics for the integer one-dimensional cutting stock problem: A computational study

In this paper the problem of generating integer solutions to the standard one-dimensional cutting stock problem is treated. In particular, we study a specific class of heuristic approaches that have been proposed in the literature, and some straightforward variants. These methods are compared with respect to solution quality and computing time. Our evaluation is based on having solved 4,000 randomly generated test problems. Not only will it be shown that two methods are clearly superior to the others but also that they solve almost any instance of the standard one-dimensional cutting stock problem to an optimum.     

Fast photochemical oxidation of proteins for comparing structures of protein-ligand complexes: the calmodulin-peptide model system

Fast photochemical oxidation of proteins (FPOP) is a mass spectrometry-based protein footprinting method that modifies proteins on the microsecond time scale. Highly reactive (?)OH, produced by laser photolysis of hydrogen peroxide, oxidatively modifies the side chains of approximately one-half the common amino acids on this time scale. Because of the short labeling exposure, only solvent-accessible residues are sampled. Quantification of the modification extent for the apo and holo states of a protein-ligand complex provides structurally sensitive information at the amino-acid level to compare the structures of unknown protein complexes with known ones. We report here the use of FPOP to monitor the structural changes of calmodulin in its established binding to M13 of the skeletal muscle myosin light chain kinase. We use the outcome to establish the unknown structures resulting from binding with melittin and mastoparan. The structural comparison follows a comprehensive examination of the extent of FPOP modifications as measured by proteolysis and LC-MS/MS for each protein-ligand equilibrium. The results not only show that the three calmodulin-peptide complexes have similar structures but also reveal those regions of the protein that became more or less solvent-accessible upon binding. This approach has the potential for relatively high throughput, information-dense characterization of a series of protein-ligand complexes in biochemistry and drug discovery when the structure of one reference complex is known, as is the case for calmodulin and M13 of the skeletal muscle myosin light chain kinase, and the structures of related complexes are not.