Analytical Modeling of Surface Potential and Drain Current of Hetero-Dielectric DG TFET and Its Analog and Radio-Frequency Performance Evaluation

Semiconductors - In the present paper, analytical modeling of surface potential and drain current for hetero-dielectric double gate tunnel FET (HDG-TFET) has been done. The two dimensional (2D)...     

A composite numerical scheme for the numerical simulation of coupled Burgers’ equation

In this work, a composite numerical scheme based on finite difference and Haar wavelets is proposed to solve time dependent coupled Burgers’ equation with appropriate initial and boundary conditions. Time derivative is discretized by forward difference and then quasilinearization technique is used to linearize the coupled Burgers’ equation. Space derivatives discretization with Haar wavelets leads to a system of linear equations and is solved using Matlab7.0. Convergence analysis of proposed scheme exhibits that the error bound is inversely proportional to the resolution level of the Haar wavelet. Finally, the adaptability of proposed scheme is demonstrated by numerical experiments and shows that the present composite scheme offers better accuracy in comparison with other existing numerical methods.     

Fungal endocarditis following cardiac surgery

This study examines the long-term prognosis of patients with an abnormal exercise radionuclide angiogram in the absence of significant angiographic coronary artery disease (CAD). In general, patients without significant CAD have an excellent prognosis, but the long-term outcome for the subset of patients with an "ischemic" exercise test is not known. In this study, 161 patients with normal coronary arteries or insignificant CAD (< 50% left main and < 70% left anterior descending, left circumflex, or right), resting left ventricular (LV) ejection fraction > or = 0.50, and an abnormal exercise radionuclide angiogram (LV ejection fraction that decreased with exercise or peak exercise LV ejection fraction < 0.60) were followed for a median duration of 11.3 years. The mean delta LV ejection fraction was -0.07, 98 patients (61%) had a decrease in LV ejection fraction of > or = 5 units, and 40 patients (25%) had peak exercise LV ejection fraction < 0.50. During follow-up there were 19 deaths (only 1 of which was cardiac), 7 nonfatal myocardial infarctions, and 9 revascularization procedures. At 12 years, overall survival was 88%, better than the expected survival for the age- and sex-matched general population. Survival free of cardiac death or myocardial infarction was 94% and survival free of any cardiac event including revascularization was 88%. Thus, patients with an abnormal exercise radionuclide angiogram but without significant CAD have an excellent long-term prognosis.     

Social Profile Aware AODV Protocol for Ad-Hoc Social Networks

Wireless Personal Communications - Ad-hoc social networks are required to strengthen local communication between people. Mobile ad-hoc social networks have emerged as self-configuring and...     

Viewpoint and the recognition of people from their movements.

Observers can recognize other people from their movements. What is interesting is that observers are best able to recognize their own movements. Enhanced visual sensitivity to self-generated movement may reflect the contribution of motor planning processes to the visual analysis of human action. An alternative view is that enhanced visual sensitivity to self-motion results from extensive experience seeing one's own limbs move. To investigate this alternative explanation, participants viewed point-light actors from first-person egocentric and third-person allocentric viewpoints. Although observers routinely see their own actions from the first-person view, participants were unable to identify egocentric views of their own actions. Conversely, with little real-world experience seeing themselves from third-person views, participants readily identified their own actions from allocentric views. When viewing allocentric displays, participants accurately identified both front and rear views of their own actions. Because people have little experience observing themselves from behind or from third-person views, these findings suggest that visual learning cannot account for enhanced visual sensitivity to self-generated action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determination of prostacyclin in plasma through a bioluminescent immunoassay for 6-keto-prostaglandin F1alpha: implication of dosage in patients with primary pulmonary hypertension

This work describes a solid-phase immunoassay for 6-keto-prostaglandin F1alpha, the stable hydrolysis product of prostacyclin (prostaglandin I2). Prostacyclin, a potent vasodilator with antiplatelet and antiproliferative properties is an effective treatment for primary pulmonary hypertension and pulmonary arterial hypertension associated with scleroderma and scleroderma-like syndrome. Levels of 6-keto-prostaglandin F1alpha can be directly correlated with levels of prostacyclin. Therefore, 6-keto-prostaglandin F1alpha, has become the indicator of choice to measure prostacyclin levels. The single-step immunoassay for 6-keto-prostaglandin F1alpha reported here was developed using the bioluminescent protein aequorin as a label. Analyte-label conjugates were constructed by linking the carboxyl group of 6-keto-prostaglandin F1alpha and lysine residues of aequorin by chemical conjugation methods. The binding properties of 6-keto-prostaglandin F1alpha toward its antibody and the bioluminescent properties of aequorin were retained in the conjugate, which was then used to generate a dose-response curve for the analyte in a convenient microtiter plate format. The concentration of 6-keto-prostaglandin F1alpha after extraction from plasma showed good correlation with the concentration of 6-ketoprostaglandin F1alpha obtained without prior extraction of the same plasma sample. This measurement demonstrated that the assay allows the measurement of 6-keto-prostaglandin F1alpha directly in plasma without any pretreatment of the samples, which results in a much simpler method with a faster assay time.     

Phosphate binding protein as the biorecognition element in a biosensor for phosphate

This work explores the potential use of a member of the periplasmic family of binding proteins, the phosphate binding protein (PBP), as the biorecognition element in a sensing scheme for the detection of inorganic phosphate (Pi). The selectivity of this protein originates from its natural role which, in Escherichia coli, is to serve as the initial receptor for the highly specific translocation of Pi to the cytoplasm. The single polypeptide chain of PBP is folded into two similar domains connected by three short peptide linkages that serve as a hinge. The Pi binding site is located deep within the cleft between the two domains. In the presence of the ligand, the two globular domains engulf the former in a hinge-like manner. The resultant conformational change constitutes the basis of the sensor development. A mutant of PBP (MPBP), where an alanine was replaced by a cysteine residue, was prepared by site-directed mutagenesis using the polymerase chain reaction (PCR). The mutant was expressed, from plasmid pSD501, in the periplasmic space of E. coli and purified in a single chromatographic step on a perfusion anion-exchange column. Site-specific labeling was achieved by attaching the fluorophore, N-[2-(1-maleimidyl)ethyl]-7-(diethylamino)coumarin-3-carboxamide (MDCC), to the protein through the sulfhydryl group of the cysteine moiety. Steady-state fluorescence studies of the MPBP-MDCC conjugate showed a change in the intensity of the signal upon addition of Pi. Calibration curves for Pi were constructed by relating the intensity of the fluorescence signal with the amount of analyte present in the sample. The sensing system was first developed and optimized on a spectrofluorometer using ml volumes of sample. It was then adapted to be used on a microtiter plate arrangement with microliter sample volumes. The system's versatility was finally proven by developing a fiber optic fluorescence-based sensor for monitoring Pi. In all three cases the detection limits for the analyte were in the sub-microMolar range. It was also demonstrated that the sensing system was selective for phosphate over other structurally-similar anions, paving the way for the design and development of a new family of biosensors utilizing the specific binding properties of periplasmic proteins.     

Effortful touch with minimum movement: Revisited.

The ecological static moment-torque model proposed by C. Carello, P. Fitzpatrick, I. Domaniewicz, T. C. Chan, and M. T. Turvey (see record 1992-18467-001) does not uniquely explain the perception of rod length by static holding. Guided by a mechanical analysis of the gravitational forces and torques produced in the hand as it statically holds rods of different lengths and materials at different orientations, we offer 2 additional theoretical explanations, the force-torque and weight-percept models. Experiment 1 demonstrates that all 3 models predict perceived rod length with considerable success. Experiment 2 provides clear experimental support for the force-torque and weight-percept models over the static moment-torque model. Experiment 3 pits the former 2 models against each other. Current results favor the weight-percept model. Implications for theories of haptic weight perception and design of a new tactile sensor are also considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of physical carrier sense based spanner construction and maintenance as well as broadcast and convergecast in ad hoc networks

While the use of physical carrier sensing for medium access control in ad hoc wireless networks is well established, exploiting physical carrier sensing directly for network layer functions is largely unexplored. We conduct extensive simulation evaluations of recently proposed algorithms that directly exploit physical carrier sensing for backbone network (spanner) construction, broadcast, and convergecast in wireless ad hoc networks. Our algorithms accommodate interference ranges larger than transmission ranges, explicitly incorporate the medium access control and packet collisions, and do not require any prior knowledge of the network. For spanner construction, our algorithms include three self-stabilizing phases that establish leader nodes able to reach all nodes in one hop, assign the leaders non-interfering transmission rounds, and connect the leaders through gateway nodes. We evaluate the backbone construction and maintenance as well as broadcast and convergecast through simulations. We find that over 75% of the control messages for backbone network construction are received from physical carrier sensing. While the number of backbone nodes is relatively large, the backbone is very robust, quickly self-stabilizing, and only a fraction of the backbone nodes are used for broadcast.