Higher Degree Of Regularity Research Articles

Reduced cardio-respiratory coupling indicates suppression of vagal activity in healthy relatives of patients with schizophrenia

Previous studies have observed reduced vagal modulation in patients with acute schizophrenia and their first-degree relatives, thus suggesting a genetic predisposition. To investigate vagal modulation, we analyzed the coupling between heart rate and breathing as a putative measure of central autonomic function in 19 patients, 19 of their relatives and 19 matched control subjects. The interaction of heart rate and breathing was investigated in all groups applying the non-linear parameter cross-ApEn, indicating the asynchrony between both time series. In addition, measures of the time and frequency domain of heart rate variability (HRV) were obtained. The main finding of our study is a significantly increased cross-ApEn value, indicating reduced central vagal modulation both in relatives and patients suffering from schizophrenia. Non-linear measures of HRV proved to more sensitively differentiate relatives from control subjects. Furthermore, we observed a correlation between psychopathology and breathing, indicating that positive symptoms are associated with a higher degree of regularity in the breathing pattern. Our results suggest that autonomic dysfunction previously described for patients suffering from schizophrenia is also present in first-degree relatives. This might relate to changes of brainstem activity in patients and relatives, and a common genetic background in patients and their family members can be assumed.

Singularity Exponent from Wavelet-Based Multiscale Analysis: A New Seismic Attribute

Seismic interpretation has been traditionally based on reflections or amplitudes. However, amplitude alone can also disguise the true nature of subsurface geology and blur stratigraphic boundaries. In many cases important information is carried by singularities that are not necessarily associated to certain amplitude patterns. We present Holder exponent (α) as a new seismic attribute which captures the locations and strengths of irregularities in the data. Holder exponent (α) is a measure of singularity strength defined at or around a point. Higher α indicates higher degree of regularity, and vice versa. It is demonstrated that α is a natural attribute for delineating stratigraphy boundaries due to its excellent abilities in detecting detailed geologic features from seismic data. We test our concept and wavelet-based multiscale analyzing algorithm on both synthetic and seismic data, and show that α improves our ability in the delineation of stratigraphy layers that would be otherwise vague in the original seismic amplitude display.

Nuclear image analysis of immunohistochemically stained cells in breast carcinomas.

Hitherto, the relationship between malignancy-associated morphological features in single tumour cells and the expression of markers indicating functional properties of these cells remained widely unknown. This study was aimed at describing differences in the size, shape and chromatin structure between tumour cells with different marker expression for progesterone receptors (PgR) and p53. Two series of breast cancers, consisting of 50 PgR-positive, and 39 p53-negative and 49 p53-positive mammary carcinomas, were investigated. The immunohistochemical staining was performed on paraffin sections using 3-amino-9-ethylcarbazole as the chromogenic substrate. By means of a cytometry workstation equipped with a computer-controlled motorised scanning stage, about 500 positive and negative tumour cells in each case were localised in the microscope and categorised by a scoring system for their staining intensity. After destaining, the tissue sections were Feulgen-stained. Then, all the tumour cells were relocated automatically and analysed by high resolution image cytometry. Among the numerous size, shape, and texture features used in the system, several variables of the nuclear contour and chromatin structure were found to be significantly different between the positive and negative tumour cell populations. Nuclei without PgR had more malignancy-associated morphological features than PgR-positive cells. Whereas p53-negative nuclei had a higher degree of regularity, their positive counterparts exhibited higher DNA ploidy values.

High-throughput VLSI architectures for the 1-D and 2-D discrete cosine transforms

This paper presents a linear systolic array and a 2-D systolic array for computing the 1-D N-point and 2-D N/spl times/N-point discrete cosine transforms (DCT's), respectively. The 1-D DCT array is constructed by using the Chebyshev polynomial to generate the transform kernel values recursively. The 2-D DCT array is based on the row-column decomposition but involves no matrix transposition problems, where the row and column transforms are evaluated similarly to the 1-D DCT. These architectures are highly regular, modular, and thus very suitable for VLSI implementation. Also, each of them has an efficiency of 100% and a throughput rate of one transform per N cycles. As compared to existing related systems, the proposed 1-D DCT array achieves the same time complexity with either much fewer I/O channels or a higher degree of regularity, while the proposed 2-D DCT array possesses better time complexity and regularity with an increase in chip area and I/O channels.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Systolic inner product arrays with automatic word rounding

In this paper, we show how word rounding techniques can be efficiently used to reduce/eliminate the guard band in systolic Inner Product Array (IPA) circuits. This results in a significant improvement in circuit throughput rate. By incorporating a shift-truncation module either in the main array cells or in the accumulator cells, two different versions of an Automatic-Rounding IPA can be produced--the unidirectional ARIPA circuit and the orthogonal ARIPA circuit. It is shown that the proposed method requires considerably less hardware and has a higher degree of regularity when compared with techniques previously proposed. Maximum system word length reduction can be achieved with the modified unidirectional ARIPA circuit at a slight increase in overall circuit complexity. This allows maximum performance to be achieved.

Morphology of Polysiloxanes Crystallized from the Melt

Poly(tetramethyl-p-silphenylene siloxanes) fractions ranging in molecular weight from below 104 to above 106, have been crystallized isothermally from the melt. Samples have also been prepared under a wide range of annealing conditions varying from minutes to hundreds of hours. The morphology of these fractured specimens has been studied by electron microscopy. The ease of fracture increases as the molecular weight decreases. The dimension of the lamellar structures ascertained from Pt shadowing and Au decoration techniques increase as the annealing or crystallization temperature is raised. The values are consistent with the crystallite sizes estimated from small-angle x-ray measurements made on these same samples, and with the single crystal thickness obtained under comparable crystallization temperatures. The topography of the fracture surfaces depends on the molecular weight and on the annealing conditions. The lower molecular weight samples (below 40 000) exhibit a much higher degree of regularity than the fractions with longer chain lengths.

Almost Regular Polyhedra

In this note I classify certain polyhedra which are of interest in that they have in some sense a higher degree of regularity than any other polyhedra except those which are completely regular. The definition of a regular polyhedron is that it shall possess two particular symmetries; one which cyclically permutes the vertices of any face c, and one which cyclically permutes the faces that meet at a vertex C, C being a vertex of c.