468 research outputs found
Using High-Rising Cities to Visualize Performance in Real-Time
For developers concerned with a performance drop or improvement in their
software, a profiler allows a developer to quickly search and identify
bottlenecks and leaks that consume much execution time. Non real-time profilers
analyze the history of already executed stack traces, while a real-time
profiler outputs the results concurrently with the execution of software, so
users can know the results instantaneously. However, a real-time profiler risks
providing overly large and complex outputs, which is difficult for developers
to quickly analyze. In this paper, we visualize the performance data from a
real-time profiler. We visualize program execution as a three-dimensional (3D)
city, representing the structure of the program as artifacts in a city (i.e.,
classes and packages expressed as buildings and districts) and their program
executions expressed as the fluctuating height of artifacts. Through two case
studies and using a prototype of our proposed visualization, we demonstrate how
our visualization can easily identify performance issues such as a memory leak
and compare performance changes between versions of a program. A demonstration
of the interactive features of our prototype is available at
https://youtu.be/eleVo19Hp4k.Comment: 10 pages, VISSOFT 2017, Artifact:
https://github.com/sefield/high-rising-city-artifac
129 Xe NMR of xenon trapped in fully dehydrated mesoporous silica
129Xe NMR spectra of natural abundant xenon gas trapped in fully dehydrated mesoporous materials with pore sizes smaller than 2 nm in diameter were observed under atmospheric pressure in the temperature range between 168 and 373 K. The average pore diameters of the materials studied in this paper were 0.5, 1 and about 2 nm for molecular sieves 5A and 13X and synthesized
mesoporous silica, respectively. The samples were fully dehydrated using an ultra-high vacuum (UHV) system and xenon gas was introduced with the sample pre-cooled to 168 K just above the boiling point of xenon. The 129Xe NMR spectra were observed as a function of increasing temperature and the 129Xe shift were observed at each temperature for the three samples under atmospheric pressure. The behaviors of xenon atoms in small pores observed in equilibrium states can provide important information on relationships between the pore structure and 129Xe chemical shift
Same File, Different Changes: The Potential of Meta-Maintenance on GitHub
Online collaboration platforms such as GitHub have provided software
developers with the ability to easily reuse and share code between
repositories. With clone-and-own and forking becoming prevalent, maintaining
these shared files is important, especially for keeping the most up-to-date
version of reused code. Different to related work, we propose the concept of
meta-maintenance -- i.e., tracking how the same files evolve in different
repositories with the aim to provide useful maintenance opportunities to those
files. We conduct an exploratory study by analyzing repositories from seven
different programming languages to explore the potential of meta-maintenance.
Our results indicate that a majority of active repositories on GitHub contains
at least one file which is also present in another repository, and that a
significant minority of these files are maintained differently in the different
repositories which contain them. We manually analyzed a representative sample
of shared files and their variants to understand which changes might be useful
for meta-maintenance. Our findings support the potential of meta-maintenance
and open up avenues for future work to capitalize on this potential.Comment: 12 pages, ICSE 202
Near-Infrared Spectroscopy of the Cool Brown Dwarf, SDSS 1624+00
Using the Subaru Telescope, we have obtained multiple near-infrared spectra
of the cool brown dwarf, SDSS 1624+00, in search of spectral variability in an
80 minute time span. We have found the suspected variability of water vapor
absorption throughout the observations, which requires confirmation by a longer
time baseline. After coadding the spectra, we have obtained a high-quality
spectrum covering 1.05 to 1.8 um. Three kinds of spectral indicators, the water
vapor bands, methane band, and KI lines in J band, suggest that SDSS 1624+00 is
warmer and dustier than Gl 229B.Comment: 6 figures, to appear in PAS
Conformational diversity of dynactin
Dynactin is a principal regulator of the minus-end directed microtubule motor dynein. The sidearm of dynactin is essential for binding to microtubules and regulation of dynein activity. Although our understanding of the structure of the dynactin backbone (Arp1 rod) has greatly improved recently, structural details of the sidearm subcomplex remain elusive. Here, we report the flexible nature and diverse conformations of dynactin sidearm observed by electron microscopy. Using nanogold labeling and deletion mutant analysis, we determined the domain organization of the largest subunit p150 and discovered that its coiled-coil (CC1), dynein-binding domain, adopted either a folded or an extended form. Furthermore, the entire sidearm exhibited several characteristic forms, and the equilibrium among them depended on salt concentrations. These conformational diversities of the dynactin complex provide clues to understanding how it binds to microtubules and regulates dynein
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