Using fuzzy logic for morphological classification of IVUS-based plaques in diseased coronary artery in the context of flow-dynamics

Plaque morphology in a diseased coronary artery plays a significant role in the modification of the fluid flow characteristics. The plaque morphology of 42 patients who underwent IVUS (intravascular ultrasound) procedure was quantified by degree of membership in four fuzzy logic sets, which we refer as type I: protruding, type II: ascending, type III: descending, and type IV: diffuse. Of 42 cases, 28% were of type I, 18% type II, 20% type III and 23% type IV, 6% belonged to hybrid types (partial members of multiple types) and the remaining 5% did not fit in any category. The degree of membership is of significance as the inter-class blood flow patterns (those strongly members of the same set) are similar to each other compared to the intra-class behavior, indicating plaque morphology (shape of blockage) is an important metric in addition to the degree of stenosis to represent the flow characteristics in a diseased stenotic coronary artery.     

Essential oil composition and antioxidant activities of alkanet (Alkanna tinctoria subsp. tinctoria)

This study is designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and the various extracts of alkanet (Alkanna tinctoria subsp. tinctoria). Gas chromatography (GC) and GC-mass spectrometry (GC-MS) analysis of the essential oil were resulted in the determination of 27 different compounds, representing 93.32% of the total oil. The major compounds detected in the oil, were pulegone (22.27%), 1,8-cineole (13.03%), α-terpinyl acetate (6.87%), and isophytol (6.83%), respectively. Antioxidant activities of the samples were determined by 4 different test systems namely β-carotene/linoleic acid, 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, and chelating effect. In all systems, essential oil showed the weakest activity profile. On the other hand, ethyl acetate and water extracts exhibited excellent antioxidant activities. As well as the antioxidant activities of the extracts, they were evaluated in terms of their total phenolic and flavonoid contents. In parallel to the experiments, ethyl acetate and water extracts were found to be rich-in these phytochemicals.     

Formulation and implementation of a high-order 3-D domain integral method for the extraction of energy release rates

This article presents a three dimensional (3-D) formulation and implementation of a high-order domain integral method for the computation of energy release rate. The method is derived using surface and domain formulations of the J-integral and the weighted residual method. The J-integral along 3-D crack fronts is approximated by high-order Legendre polynomials. The proposed implementation is tailored for the Generalized/eXtended Finite Element Method and can handle discontinuities arbitrarily located within a finite element mesh. The domain integral calculations are based on the same integration elements used for the computation of the stiffness matrix. Discontinuities of the integrands across crack surfaces and across computational element boundaries are fully accounted for. The proposed method is able to deliver smooth approximations and to capture the boundary layer behavior of the J-integral using tetrahedral meshes. Numerical simulations of mode-I and mixed mode benchmark fracture mechanics examples verify expected convergence rates for the computed energy release rates. The results are also in good agreement with other numerical solutions available in the literature.     

n–p transformation in TlBi(1−x)SbxTe2 system

TlBi_(1?x)Sb_xTe₂ quaternary crystals that crystallize in a rhombohedral structure and according to their properties are classified between semimetals and narrow energy gap semiconductors, are studied. The study of their optical and electrical behavior reveal that they are quite sensitive to the Sb content x, and it is found that the substitution of Bi- with Sb-atoms in TlBiTe₂ crystals leads initially to a decrease in the plasma frequency. However, for higher Sb contents, the plasma frequency increases. At room temperature, samples with x < 0.8 are n-type semiconductors, becoming p-type ones for x > 0.8.A model suggesting a suppression of the free electron concentration induced by the incorporation of Sb atoms into the crystal lattice of TlBiTe₂ is used to explain this transition in the conductivity type.     

An analytical framework for the design and performance evaluation of realistic Aloha-CDMA systems

The random access scheme has been shown to be an efficient transfer mechanism of packet data in wireless environments for nonreal-time applications where messages with variable length are transmitted over power controlled code-division multiple-access (CDMA) channels. Most of the previous work in this area covered the analysis of the CDMA systems for fixed or exponential packet length, infinite population, and unlimited waiting and service time where the results mainly depend on the mean values of the traffic. In this paper, we remove these assumptions and analyze the behavior of the system for the more general and realistic case of finite population, finite sojourn time, and general packet length distribution. Specifically, we provide an analytical method to study the performance related parameters of the system, such as packet delay, packet loss, and throughput as well as the effect of packet length distribution on the system performance under a realistic environment. The obtained results demonstrate that for the packet length distributions with the same mean but different tail properties, the system behavior can change dramatically. In addition, we demonstrate that this study provides an analytical tool that can be used as the underlying framework for the support of a wide range of applications and management functions such as optimization of design parameters, integration of multimedia services, and anomaly detection in CDMA wireless networks.     

Higher order iminodiacetic acid libraries for probing protein-protein interactions

Full details of the preparation of iminodiacetic acid diamide dimer (2040 compounds), trimer (560 compounds), and tetramer (1596 compounds) libraries by multistep convergent solution-phase synthesis for studying protein-protein interactions are provided. The libraries were assembled in a format providing small 8-10 compound mixtures and the deconvolution of many of the small mixtures to identify screening leads by resynthesis of the individual components have been conducted for 320 of the individual compounds to date. A representative example of the subsequent exploration of the structure-activity relationships for an identified receptor binding antagonist (200 additional individual compounds) and steps taken for potential elaboration to a receptor dimerization agonist are defined with preparation of representative linked dimers (70 compounds).     

Construct validation of optimism and pessimism in older men: Findings from the normative aging study.

Validation of M. F. Scheier and C. S. Carver's (1985) Life Orientation Test has identified associations between bipolar optimism and several external constructs. However, optimism and pessimism may not be bipolar, but rather separate constructs. Furthermore, these constructs may be indistinguishable from personality traits, such as neuroticism and extraversion. This study examined the associations of separate optimism and pessimism measures with self-reports of hassles, psychological symptoms, and illness severity, controlling for personality. Ss were 1,192 men from the Normative Aging Study. Findings suggest that optimism and pessimism are separate and that their relations to external criteria remain, although attenuated, when neuroticism and extraversion are controlled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A hierarchical human detection system in (un)compressed domains

We propose a hierarchical retrieval system where shape, color and motion characteristics of the human body are captured in compressed and uncompressed domains. The proposed retrieval method provides human detection and activity recognition at different resolution levels from low complexity to low false rates and connects low level features to high level semantics by developing relational object and activity presentations. The available information of standard video compression algorithms are used in order to reduce the amount of time and storage needed for the information retrieval. The principal component analysis is used for activity recognition using MPEG motion vectors and results are presented for walking, kicking, and running to demonstrate that the classification among activities is clearly visible. For low resolution and monochrome images it is demonstrated that the structural information of human silhouettes can be captured from AC-DCT coefficients.     

Antimicrobial and antioxidant properties of the essential oils and methanol extract from Mentha longifolia L. ssp. longifolia

This study was designed to evaluate antimicrobial and antioxidant activities of the essential oil and methanol extract from Mentha longifolia ssp. longifolia. The essential oil showed strong antimicrobial activity against all 30 microorganisms tested whereas the methanol extract almost remained inactive. In contrast, the extract showed much better activity than the essential oil in antioxidant activity assays employed, e.g. in the inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene/linoleic acid systems. In the former, the extract was able to reduce the stable free radical DPPH with an IC₅₀ of 57.4 μg/ml while that of the oils was 10 700 μg/ml. When compared to BHT, a synthetic antioxidant, both showed weaker antioxidative potential. Similarly, in β-carotene/linoleic acid assay, these samples were not effectively able to inhibit the linoleic acid oxidation; exhibiting only 24% and 36% inhibitions at 2 mg/ml, respectively; both were far below than that of BHT. Total phenolic constituent of the extract was 4.5 g/100 g as gallic acid equivalent. GC–MS analysis of the oil resulted in the identification of 45 constituents, cis-piperitone epoxide, pulegone and piperitenone oxide being the main components.