Abrogation of p53 function affects gadd gene responses to DNA base-damaging agents and starvation

The tumor suppressor p53 is required for induction of its downstream effector genes such as GADD45 and CIP1/WAF1 by ionizing radiation (IR). This response is probably mediated through defined p53 binding sites located in the promoter of CIP1/WAF1 and in the third intron of GADD45. In contrast, the gadd gene stress response to base-damaging agents, such as methylmethane sulfonate (MMS) or UV radiation, or medium depletion (starvation) occurs in all mammalian cells examined to date regardless of p53 status for both GADD45 and also GADD153, which is not IR-responsive in many lines with functional p53. These agents strongly induce the p53 protein and raise the possibility that, although p53 is not required for the typical "gadd" response to these agents, p53 may contribute to these non-IR stress responses. This possibility was confirmed by the finding that disruption of p53 function by transfection with dominant-negative vectors expressing HPV E6, mutant p53, or SV40 T Ag reduced the induction of GADD45 and GADD153 as measured by increases in mRNA and protein levels in human lines with wild-type p53. Similarly, induction of these genes by MMS or UV radiation was consistently stronger in the parental mouse embryo fibroblasts compared to cells derived from mice where both p53 alleles had been deleted. Similar qualitative responses were also seen for CIP1/WAF1. In agreement with reduced induction of p53-regulated genes, the G1 checkpoint activated by MMS or UV radiation was markedly abrogated in p53-wt human MCF-7 breast carcinoma cells by E6 expression. Interestingly, induction of reporter constructs driven by the GADD45 or GADD153 promoters was substantially reduced in human cells transfected with mutant p53 or E6 expression vectors or in cells lacking p53 following treatment with MMS, UV radiation, or starvation. Because neither promoter is inducible by IR, and neither contains a strong p53 binding site, these results indicate that p53 has a synergistic or cooperative role in these non-IR stress responses for both GADD45 and GADD153, and that this role is not mediated through identifiable p53-binding sites.     

Design sensitivity analysis of acoustical damping and its application to design of musical bells

Damping characteristics of a musical bell plays an important role in characterizing the musical sound. The total damping consists of acoustical damping and internal damping. Acoustical damping depends upon resonating frequencies and vibration patterns while internal damping is a material property. The acoustical damping of a vibrating structure is formulated via boundary element method and finite element method using eigenmode decomposition. The design sensitivity of acoustical damping is derived using an adjoint variable method of the eigenvalue problem. Design optimization of a musical bell is then performed in terms of acoustical parameters. The goal of the optimization problem is to design a harmonically tuned bell with given acoustical damping values. The proposed automated design process integrates finite element analysis, boundary element analysis, design sensitivity analysis, mode-tracking algorithm and optimization module, seamlessly. It is demonstrated by numerical examples to show practical applications.     

Adaptive observer-based trajectory tracking control of nonholonomic mobile robots

In this paper, an adaptive observer-based trajectory tracking problem is solved for nonholonomic mobile robots with uncertainties. An adaptive observer is first developed to estimate the unmeasured velocities of a mobile robot with model uncertainties. Using the designed observer and the backstepping technique, a trajectory tracking controller is designed to generate the torque as an input. Using Lyapunov stability analysis, we prove that the closed-loop system is asymptotically stable with respect to the estimation errors and tracking errors. Finally, the simulation results are presented to validate the performance and robustness of the proposed control system against uncertainties.     

Critical point analysis using domain lifting for fast geometry queries

In this paper, a general scheme for solving coherent geometric queries on freeform geometry is presented and demonstrated on a variety of problems common in geometric modeling. The underlying strategy of the approach is to lift the domain of the problem into a higher-dimensional space to enable analysis on the continuum of all possible configurations of the geometry. This higher-dimensional space supports analysis of changes to solution topology by solving for critical points using a B-spline-based constraint solver. The critical points are then used to guide fast, local methods to robustly update repeated queries. This approach effectively combines the speed of local updates with the robustness of global search solutions. The effectiveness of the domain lifting scheme (DLS) is demonstrated on several geometric computations, including accurately generating offset curves and finding minimum distances. Our approach requires a preprocessing step that computes the critical points, but once the topology is analyzed, an arbitrary number of geometry queries can be solved using fast local methods. Experimental results show that the approach solves for several hundred minimum distance computations between planar curves in one second and results in a hundredfold speedup for trimming self-intersections in offset curves.     

Memory effects of all‐solution‐processed oxide thin‐film transistors using ZnO nanoparticles

Abstract— Non‐volatile memory effects of an all‐solution‐processed oxide thin‐film transistor (TFT) with ZnO nanoparticles (NPs) as the charge‐trapping layer are reported. The device was fabricated by using a soluble MgInZnO active channel on a ZrHfO^x gate dielectric. ZnO NPs were used as the charge‐trapping site at the gate‐insulator—channel interface, and Al was used for source and drain electrodes. Transfer characteristics of the device showed a large clockwise hysteresis, which can be used to demonstrate its memory function due to electron trapping in the ZnO NP charge‐trapping layer. This memory effect has the potential to be utilized as a memory application on displays and disposable electronics.     

A new vertical‐alignment LC mode with high‐transmittance and fast‐response‐time features

Abstract— A novel pixel design for vertical‐alignment LCDs with superior transmittance has been developed. The new liquid‐crystal mode, refered to as the hole‐induced vertical‐alignment mode (Hi‐VA), uses a via hole of an organic layer on a TFT substrate to achieve multi‐domain alignment. Compared to the conventional design, the Hi‐VA mode has a transmittance of up to 135% with a contrast ratio of 2000:1. Moreover, the new structure is free from ITO patterning or protrusion on the color‐filter side, which makes the fabrication process simple and low cost.     

Simulation framework for small scale engagement

Developing future weapons systems has become increasingly complicated and costly. The armed forces of major nations use modeling and simulation techniques for new weapons systems from the conceptual stage to design, production, deployment and training stages to shorten the development cycle and guarantee their effectiveness. Failure in the development cycle carries too much loss in time and money. Therefore, computer-based modeling and simulation techniques are applied from the conceptual stage to gauge the efficacy of new weapons systems. The objective of this study is to develop a modeling and simulation methodology for small scale engagement using the DEVS formalism. The entities required for modeling and simulation are divided into three categories: combat, logical, and environmental entities. Combat entities represent the military hardware or combatants; logical entities represent the judgment and decision entities for the interaction between various entities; and environmental entities emulate the constituents of real combat environment. The combat entities are further modeled into Shell and Core Parts to maximize their reusability under various combat scenarios. The proposed framework is verified using a one-on-one combat engagement simulation (written in C++) between two submarines.     

A new multi-unit iris authentication based on quality assessment and score level fusion for mobile phones

Although iris recognition technology has been reported to be more stable and reliable than other biometric systems, performance can be degraded due to many factors such as small eyes, camera defocusing, eyelash occlusions and specular reflections on the surface of glasses. In this paper, we propose a new multi-unit iris authentication method that uses score level fusion based on a support vector machine (SVM) and a quality assessment method for mobile phones. Compared to previous research, this paper presents the following two contributions. First, we reduced the false rejection rate and improved iris recognition accuracy by using iris quality assessment. Second, if even two iris images were determined to be of bad quality, we captured the iris images again without using a recognition process. If only one iris image among the left and right irises was regarded as a good one, it was used for recognition. However, if both the left and right iris images were good, we performed multi-unit iris recognition using score level fusion based on a SVM. Experimental results showed that the accuracy of the proposed method was superior to previous methods that used only one good iris image or those methods that used conventional fusion methods.     

MIMO-OFDM PAPR reduction by selected mapping using side information power allocation

In this paper, we present a Selected Mapping (SLM) PAPR reduction technique for MIMO-OFDM system with special protection of Side Information (SI). Selected Mapping (SLM) is a powerful PAPR reduction technique since it does not cause any signal distortion and simple to implement. As a special protection for the Side Information (SI) of SLM technique, we propose a SI power allocation procedure. Simulation results show that our proposed technique gives significantly better BER performance than the ordinary SLM technique for MIMO-OFDM systems. Analysis for the optimum SI power allocation is also presented.