An execution profiler for window-oriented applications

Execution profiles are important in analyzing the performance of computer programs on a given computer system. However, accurate and complete profiles are difficult to arrive at for programs that follow the client-server model of computing, as in the popular X Window System. In X Window applications, considerable computation is invoked at the display server and this computation is an important part of the overall execution profile. The profiler presented in this paper generates meaningful profiles for X Window applications by estimating the time spent in servicing the messages in the display server. The central idea is to analyze a protocol-level trace of the interaction between the application and the display server and thereby construct an execution profile from the trace and a set of metrics about the target display server. Experience using the profiler for examining bottlenecks is presented.     

Amination of Buckminsterfullerene C60 at Low Temperature: Application in Polyamide Synthesis

Addition of diamines to C₆₀ was performed under different conditions.; it proceeded efficiently at low temperatures. Reaction of the adducts with dicarboxylic acid derivatives produced polyamides. Interaction between amines and C₆₀ was studied by molecular modeling.     

Using profile information to assist classic code optimizations

This paper describes the design and implementation of an optimizing compiler that automatically generates profile information to assist classic code optimizations. This compiler contains two new components, an execution profiler and a profile-based code optimizer, which are not commonly found in traditional optimizing compilers. The execution profiler inserts probes into the input program, executes the input program for several inputs, accumulates profile information and supplies this information to the optimizer. The profile-based code optimizer uses the profile information to expose new optimization opportunities that are not visible to traditional global optimization methods. Experimental results show that the profile-based code optimizer significantly improves the performance of production C programs that have already been optimized by a high-quality global code optimizer.     

Subsolidus Compatibilities in the Y2O3-BaO-CuO System via Diamagnetic Susceptibility

Subsolidus compatibilities in the YO_1.5-BaO-CuO system involving the superconducting 1:2:3 compound have been determined via optical microscopy, X-ray diffraction, and diamagnetic susceptibility measurements. The susceptibility is particularly sensitive to the presence or absence of the superconducting phase.     

Quality improvement of ultrathin gate oxide by using thermal growth followed by SF ANO technique

Rapid thermal oxide followed by anodization in direct current superimposed with scanning frequency alternating current was demonstrated for the first time to have an improved quality in ultrathin gate oxides. Compared with the thermal oxide grown without the scanning-frequency anodization (SF ANO) treatment, the gate leakage current density (J/sub g/) of SF ANO sample is significantly reduced without increasing the thickness of gate oxide. In addition, it could be observed that the interface trap density (D/sub it/) is reduced with tighter distribution. It is suggested that the bulk traps and interface traps in thermally grown oxide can be repaired during the SF ANO process.     

Performance of the Continuous Performance Test among community samples

Pericentrin and gamma-tubulin are integral centrosome proteins that play a role in microtubule nucleation and organization. In this study, we examined the relationship between these proteins in the cytoplasm and at the centrosome. In extracts prepared from Xenopus eggs, the proteins were part of a large complex as demonstrated by sucrose gradient sedimentation, gel filtration and coimmunoprecipitation analysis. The pericentrin-gamma-tubulin complex was distinct from the previously described gamma-tubulin ring complex (gamma-TuRC) as purified gamma-TuRC fractions did not contain detectable pericentrin. When assembled at the centrosome, the two proteins remained in close proximity as shown by fluorescence resonance energy transfer. The three- dimensional organization of the centrosome-associated fraction of these proteins was determined using an improved immunofluorescence method. This analysis revealed a novel reticular lattice that was conserved from mammals to amphibians, and was organized independent of centrioles. The lattice changed dramatically during the cell cycle, enlarging from G1 until mitosis, then rapidly disassembling as cells exited mitosis. In cells colabeled to detect centrosomes and nucleated microtubules, lattice elements appeared to contact the minus ends of nucleated microtubules. Our results indicate that pericentrin and gamma-tubulin assemble into a unique centrosome lattice that represents the higher-order organization of microtubule nucleating sites at the centrosome.     

Design consideration of monolithic millimeter-wave barrier varactor diode frequency multiplier arrays

A new device structure for highly efficient frequency tripling in the millimeter and submillimeter wavelength regions is presented. The Barrier-Intrinsic-N⁺ (BIN) diode structure [1,2] is modified for highly efficient millimeter- and submillimeter-wave frequency tripling device to be employed into the monolithic back-to-back diode frequency tripler array. The modified BIN diode structures have series resistances of a few ohms and cut-off frequencies in the terahertz range. The modified BIN diode structures have weaker C-V nonlinearities than the BIN diode structure does, however, the modified BIN structures have much higher intrinsic cut-off frequencies than does the BIN counterpart. The C-V nonlinearity, capacitance ratio, breakdown voltage, series resistance and cut-off frequency of this new device structure will be discussed in this paper. In addition, the calculated high-frequency performance of this device using a large-signal nonlinear circuit model will be presented in this paper. The operation and performance of the monolithic diode-grid frequency tripler arrays employing large numbers of the modified BIN diodes will also be discussed in this paper.     

Enhanced x-ray irradiation-induced cancer cell damage by gold nanoparticles treated by a new synthesis method of polyethylene glycol modification

We explored a very interesting gold nanoparticle system-pegylated gold in colloidal solution-and analyzed its uptake by mice colorectal adenocarcinoma CT26 tumor cells and the impact on the cell's response to x-ray irradiation. We found that exposure to polyethylene glycol (PEG) modified ('pegylated') 4.7 ± 2.6?nm gold nanoparticles synthesized by a novel synchrotron-based method enhances the response of CT26 cells to x-ray irradiation. Transmission electron microscopy (TEM) and confocal microscopy revealed that substantial amounts of such nanoparticles are taken up and absorbed by the cells and this conclusion is supported by quantitative induced coupled plasma (ICP) results. Standard tests indicated that the internalized particles are highly biocompatible but strongly enhance the cell damage induced by x-ray irradiation. Synchrotron radiation Fourier transform infrared (SR-FTIR) spectromicroscopy analyzed the chemical aspects of this phenomenon: the appearance of C = O stretching bond spectral features could be used as a marker for cell damage and confirmed the enhancement of the radiation-induced toxicity for cells.     

Real-time detection of linear and angular displacements with a modified DVD optical head

Here we demonstrate that an astigmatic detection system (ADS), constructed with a modified digital-versatile-disk (DVD) optical head, can achieve real-time measurement of a linear displacement and two-dimensional (2D) tilt angles with a high sensitivity. An atomic force microscope (AFM), using our detection system to sense the deflection of microfabricated cantilevers, can resolve single atomic steps on graphite surfaces with a noise level less than 0.04?nm in topographic images. This astigmatic detection system can even detect mechanical resonances due to thermal vibrations of microfabricated cantilevers. The high sensitivity, small detecting size and high bandwidth of this detection system is suitable for dynamic characterization of elements in micromachined components. Further optimization of the system will promise many other applications in diverse technological fields.