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Study of monogenic mitochondrial cardiomyopathies may yield insights into mitochondrial roles in cardiac development and disease. Here, we combined patient-derived and genetically engineered induced pluripotent stem cells (iPSCs) with tissue engineering to elucidate the pathophysiology underlying the cardiomyopathy of Barth syndrome (BTHS), a mitochondrial disorder caused by mutation of the gene encoding tafazzin (TAZ). Using BTHS iPSC-derived cardiomyocytes (iPSC-CMs), we defined metabolic, structural and functional abnormalities associated with TAZ mutation. BTHS iPSC-CMs assembled sparse and irregular sarcomeres, and engineered BTHS 'heart-on-chip' tissues contracted weakly. Gene replacement and genome editing demonstrated that TAZ mutation is necessary and sufficient for these phenotypes. Sarcomere assembly and myocardial contraction abnormalities occurred in the context of normal whole-cell ATP levels. Excess levels of reactive oxygen species mechanistically linked TAZ mutation to impaired cardiomyocyte function. Our study provides new insights into the pathogenesis of Barth syndrome, suggests new treatment strategies and advances iPSC-based in vitro modeling of cardiomyopathy., BTHS is an X-linked cardiac and skeletal mitochondrial myopathy caused by mutation of the gene encoding tafazzin (1), an acyltransferase responsible for normal acylation of cardiolipin, the major phospholipid of [...]

We developed and evaluated a new parent report instrument--Parent Observation of Early Markers Scale (POEMS)--to monitor the behavioral development of infants at risk for autism spectrum disorder (ASD) because they have older affected siblings. Parents of 108 at-risk infants (74 males, 34 females) completed the POEMS from child age 1-24 months. The POEMS had acceptable psychometric properties and promising predictive validity. Most concerning items were social and communication deficits, and intolerance to waiting. Results provide preliminary evidence that prospective parent report measures can help to detect early ASD symptoms in infants at biological risk. We invite researchers to join us in multi-center studies of the POEMS. Keywords Early identification * At-risk infants, Introduction Need for Early ASD Screening Children with possible Autism Spectrum Disorders (ASDs) are not typically diagnosed before 4 years of age (Kleinman et al. 2008). The American Academy of [...]

The mammalian heart is formed from distinct sets of first and second heart field (FHF and SHF, respectively) progenitors. Although multipotent progenitors have previously been shown to give rise to cardiomyocytes, smooth muscle, and endothelial cells, the mechanism governing the generation of large numbers of differentiated progeny remains poorly understood. We have employed a two-colored fluorescent reporter system to isolate FHF and SHF progenitors from developing mouse embryos and embryonic stem cells. Genome-wide profiling of coding and noncoding transcripts revealed distinct molecular signatures of these progenitor populations. We further identify a committed ventricular progenitor cell in the IsLet 1 lineage that is capable of limited in vitro expansion, differentiation, and assembly into functional ventricular muscle tissue, representing a combination of tissue engineering and stem cell biology. 10.1126/science.1177350

INTRODUCTION Failure to incorporate security into systems requirements is a concern dating back at least a quarter of a century (Schell, Downey & Popek, 1973, Pipkin, 2000). Compounding this oversight […], Information assurance, data security, and corresponding issues are traditionally presented in Systems Analysis and Design textbooks as non-functional requirements. Systems analysts can enforce secure design and code as one of the essential goals of systems analysis and design by using the Reference Monitor concept as a means of requirements and design specification. The application of the Reference Monitor during the early stages of systems requirements specification via the Use Case emphasizes that information assurance is a critical functional requirement.

Cytoskeletal microtubules have been proposed to influence cell shape and mechanics based on their ability to resist large-scale compressive forces exerted by the surrounding contractile cytoskeleton. Consistent with this, cytoplasmic microtubules are often highly curved and appear buckled because of compressive loads. However, the results of in vitro studies suggest that microtubules should buckle at much larger length scales, withstanding only exceedingly small compressive forces. This discrepancy calls into question the structural role of microtubules, and highlights our lack of quantitative knowledge of the magnitude of the forces they experience and can withstand in living cells. We show that intracellular microtubules do bear large-scale compressive loads from a variety of physiological forces, but their buckling wavelength is reduced significantly because of mechanical coupling to the surrounding elastic cytoskeleton. We quantitatively explain this behavior, and show that this coupling dramatically increases the compressive forces that microtubules can sustain, suggesting they can make a more significant structural contribution to the mechanical behavior of the cell than previously thought possible.

The electronic information gathering process called the multi-class interest profile is discussed.

Vibration induced by an alternating magnetic field is proposed as a method for the identification of modified brachytherapy seeds with Doppler ultrasound. In vitro experiments with agar and liver-tissue phantoms using a clinical scanner and simple apparatus demonstrate that the technique is feasible. Index Terms--Brchytherapy, Doppler, guidance, prostate, ultrasound.

Research is presented concerning the development of an ultrasound resolution test object that consists of a thin planar substrate which acoustically matches the media surrounding it. The production of a Doppler spectral signal is discussed.

Fully developed speckle patterns seen in coherent imagery were characterized by a Rayleigh-distributed envelope amplitude. Non-Rayleigh distributions were seen in many cases, such as when the number of scatterers in a resolution cell is small or scatterers are organized with some periodicity. The effects of assuming that scattering is described in one dimension by a stationary renewal process in which the arrival times are the locations of ideal point scatterers, the interscatterer distances are drawn from a gamma distribution and the scatterer amplitudes are permitted to be correlated in space, were studied.

Some of the views of Howard N. Garb, Colleen M. Florio and William M. Grove regarding the use of Rorschach scales as the validating criterion for other Rorschach scales invite comment. They failed to realize the meaning of the differences between convergent-validity results for the Rorschach and Minnesota Multiphasic Personality Inventory. In addition, they did not carry a series of scale-focused reviews to determine the merits of the Rorschach.

We have developed a computationally simple model for calculating the magnetic-field strength at a point due to a single motor unit compound action potential (SMUCAP). The motor unit is defined only in terms of its anatomical features, and the SMUCAP is approximated using the tripole model. The distributed current density J is calculated within the volume defined by the motor unit. The law of Biot and Savart can then be cast in a form necessitating that J be integrated only over the region containing current sources or conductivity boundaries. The magnetic-field strength is defined as the summation of the contributions to the field made by every muscle fiber in the motor unit. Applying this model to SMUCAP measurements obtained using a high-resolution SUper Conducting Quantum Interference Device (SQUID) magnetometer may yield information regarding the distribution of action currents (AC's) and the anatomical properties of single motor units within a muscle bundle. Index Terms - Electromyogram, magnetomyogram, mathematical model, SQUID.

A semiautomated feature extraction-algorithm is presented for the extraction and measurement of the hippocampus from volumetric magnetic resonance imaging (MRI) head scans. This algorithm makes use of elements of both deformable model and region growing techniques and allows incorporation of a priori operator knowledge of hippocampal location and shape. Experimental results indicate that the algorithm is able to estimate hippocampal volume and asymmetry with an accuracy which approaches that of laborious manual outlining techniques. Index Terms - Deformable model, feature extraction, MRI, three-dimensional.

Discrete wavelet transform (DWT) provides an advantageous framework of multiresolution space-frequency representation with promising applications in image processing. The challenge as well as the opportunity in wavelet-based compression is to exploit the characteristics of the subband coefficients with respect to both spectral and spatial localities. A common problem with many existing quantization methods is that the inherent image structures are severely distorted with coarse quantization. Observation shows that subband coefficients with the same magnitude generally do not have the same perceptual importance; this depends on whether or not they belong to clustered scene structures. We propose in this paper a novel scene adaptive and signal adaptive quantization scheme capable of exploiting both the spectral and spatial localization properties resulting from wavelet transform. The proposed quantization is implemented as a maximum a posteriori probability (MAP) estimation-based clustering process in which subband coefficients are quantized to their cluster means, subject to local spatial constraints. The intensity distribution of each cluster within a subband is modeled by an optimal Laplacian source to achieve the signal adaptivity, while spatial constraints are enforced by appropriate Gibbs random fields (GRF) to achieve the scene adaptivity. Consequently, with spatially isolated coefficients removed and clustered coefficients retained at the same time, the available bits are allocated to visually important scene structures so that the information loss is least perceptible. Furthermore, the reconstruction noise in the decompressed image can be suppressed using another GRF-based enhancement algorithm. Experimental results have shown the potentials of this quantization scheme for low bit-rate image and video compression. Index Terms - Adaptive quantization, image and video compression, Gibbs random field, spatial contraints, subband coding, wavelet coding.

A new formulation for the data reduction of the absolute backscatter coefficient from pulse-echo measurements is examined. The formulation enables straightforward diffraction correction and system calibration. It uses simple functions with tractable approximations which are simple constants in some cases. A reference plate is used to achieve system calibration.

Mothers' representations and their infants are assessed prenatally to determine the stability and association with infants' attachment classifications. The study used the Working Model of the Child Interview (WMCI) where mothers' representations of their infants were assessed prenatally while the infant Strange Situation attachment classifications was also examined. Results gathered by the WMCI show problems in skewed distribution of the sample.

A strategy for artifact reduction of low bit rate discrete-cosine-transform-compressed images is shown. First, the DC coefficients are calibrated by employing gradient continuity constraints. Next, an enhanced Huber-Markov-random-field-based smoothing is employed. The constrained optimization is performed by the iterative conditional mode. Final reconstructions of typical images with enhancements in both visual quality and peak signal-to-noise ratio are demonstrated.

We present a human face location technique based on contour extraction within the framework of a wavelet-based video compression scheme for videoconferencing applications. In addition to an adaptive quantization in which spatial constraints are enforced to preserve perceptually important information at low bit rates, semantic information of the human face is incorporated to design a hybrid compression scheme for videoconferencing since the human face is often the most important portion within a frame and should be coded with high fidelity. The human face is detected based on contour extraction and feature point analysis. An approximated face mask is then used in the quantization of the decomposed subbands. At the same total bit rate, coarser quantization of the background enables the face region to be quantized finer and coded with higher quality. Simulation results have shown that the perceptual image quality can be greatly improved using the proposed scheme.

In the butterfly search technique, echoes from repeated firings of a transducer are resampled along a set of predetermined trajectories of constant velocities, called 'butterfly lines,' because of their intersection and crossing at a reference range. The slope of the trajectory on which the sampled signals satisfy a predetermined criterion appropriate for the type of signal in question, provides an estimate of the velocity of the target. The search for this trajectory is called 'butterfly search,' which can be carried out efficiently in a parallel processing scheme. The estimator can be based on the radio frequency (RF) Alines, the envelopes, or the quadrature components. The butterfly search on quadrature components has shown outstanding noise immunity, even with relatively few successive scan lines, and was found to outperform all the common time domain and Doppler techniques in simulations and experiments with strong noise. It can be simply implemented using elementary digital signal processing hardware. However, it is possible to further improve upon its computational complexity to make the technique even simpler to implement, without any complex multipliers in the parallel channels. In this paper, we present some modifications that significantly reduce the computational complexity of butterfly search on quadrature components.

Factor scores for the Wechsler Adult Intelligence Scale-Revised (WAIS-R) are commonly computed using procedures involving equally weighted sums of the subtests that load the highest on the estimated factor. It is contended that this approach is flawed because the factor scores generated do not have discriminant validity. The statistical consequences of using equal weights in estimating the WAIS-R factors scores are examined.

A study of factor score estimation procedures of the third version of Wechsler Intelligence Scale for Children (WISC-III), using weights measured for factors such as Verbal Comprehension, Perceptual Organization, Freedom From Distractability, Processing Speed and unrotated factors such as General Intelligence, revealed that differentially weighted estimates measured using a spreadsheet should supplement equally weighted estimates. The equally-weighted factor estimates lack discriminant validity. The scattered nature of the five performance IQ subtests, including picture arrangement and block design, confirmed the variation between the two factor estimates.

Johann Winckelmann's 'History of Ancient Art' dwells on the history of the depiction of the human body, particularly the young male body. His telling of the history is actually a continuation of that history, given Winckelmann's classical sensibilities and erotic devotion to his subject matter. He demurred from presenting a theoretical account of beauty because, following Plato, he regarded beauty as incapable of demonstration. It can only be revealed. The corruption of nature, and hence of the possibilities of beauty, distinguishes the present from the ideal of antiquity, never to be recaptured.

Most recent work concerned with intuition has emphasized the errors of intuitive judgment in the context of justification. The present research instead views intuition as informed judgment in the context of discovery. Two word tasks and a gestalt closure task were developed to investigate this concept of intuition. Two of these tasks demonstrated that people could respond discriminatively to coherence that they could not identify, and a third task demonstrated that this tacit perception of coherence guided people gradually to an explicit representation of it in the form of a hunch or hypothesis. While such hunches may surface quite suddenly into consciousness, we propose that the underlying cognitive processes which produce them are more continous than discontinuous in nature. Specifically, we argue that clues to coherence automatically activate the problem solver's relevant mnemonic and semantic networks. Eventually the level of patterned activation is sufficient to cross a threshold of consciousness, and at that point, it is represented as a hunch or hypothesis. The largely unconscious processes involved in generating hunches is quite different from the conscious processes required to test them--thereby vindicating the classical distinction between the context of discovery and the context of justification.

An experimental test was conducted to examine the behavioral discrimination in North Island (NI) saddlebacks Philesturnus rufusafer exposed to familiar and unfamiliar male rhythmical song (MRS) and determine the divergence of conspecific recognition signals (CRS) among isolated populations. The obtained results demonstrated the rapid tempo with which discrimination of CRS might evolve within isolated populations and supported both bottleneck and cultural mutation hypotheses in CRS evolution.

Byline: Kevin R. Parker, Thomas A. Ottaway, Joseph T. Chao Historically, the selection of a programming language for an introductory programming course has been a process consisting of faculty evaluation, discussion, and consensus. As the number of faculty, students, and language options grows, this process is likely to become increasingly unwieldy. In addition, the process lacks structure and cannot be easily replicated. The selection process will, in all likelihood, be repeated every two to three years. Providing a structured approach to the selection of a programming language would yield a more thorough evaluation of the options available and a more easily justified selection. Developing and documenting an exhaustive set of selection criteria, and an approach for the application of these criteria, will allow the process of language selection to be more easily repeated in the future. This paper presents a comprehensive set of criteria that should be considered when selecting a programming language for a teaching environment, and proposes several approaches for the application of these criteria.

Byline: Kevin R. Parker, Philip S. Nitse Knowledge management encompasses the entire intelligence cycle from planning to reporting. One aspect that is often overlooked or minimised is the inclusion of competitive intelligence. This paper proposes a new concept to fine-tune the process of electronically gathering competitive intelligence a key activity in knowledge management systems. Most tools are nondiscriminatory in information gathering, and a structured approach is needed to assist managers at all organisational levels in the needs identification process. The proposed multiclass interest profile provides the capability of expanding the coverage of critical intelligence areas to reflect the assorted topics that make up an organisation's information needs. Each component is customisable to make the information that is gathered pertinent to the organisation, and supporting features such as profile expansion and fine-tuning are also incorporated.