319 research outputs found
Optimizing Test Pattern Generation Using Top-Off ATPG Methodology for StuckâAT, Transition and Small Delay Defect Faults
The ever increasing complexity and size of digital circuits complemented by Deep Sub Micron (DSM) technology trends today pose challenges to the efficient Design For Test (DFT) methodologies. Innovation is required not only in designing the digital circuits, but also in automatic test pattern generation (ATPG) to ensure that the pattern set screens all the targeted faults while still complying with the Automatic Test Equipment (ATE) memory constraints.
DSM technology trends push the requirements of ATPG to not only include the conventional static defects but also to include test patterns for dynamic defects. The current industry practices consider test pattern generation for transition faults to screen dynamic defects. It has been observed that just screening for transition faults alone is not sufficient in light of the continuing DSM technology trends. Shrinking technology nodes have pushed DFT engineers to include Small Delay Defect (SDD) test patterns in the production flow. The current industry standard ATPG tools are evolving and SDD ATPG is not the most economical option in terms of both test generation CPU time and pattern volume. New techniques must be explored in order to ensure that a quality test pattern set can be generated which includes patterns for stuck-at, transition and SDD faults, all the while ensuring that the pattern volume remains economical.
This thesis explores the use of a âTop-Offâ ATPG methodology to generate an optimal test pattern set which can effectively screen the required fault models while containing the pattern volume within a reasonable limit
SImMER: A Pipeline for Reducing and Analyzing Images of Stars
We present the first public version of SImMER, an open-source Python
reduction pipeline for astronomical images of point sources. Current
capabilities include dark-subtraction, flat-fielding, sky-subtraction, image
registration, FWHM measurement, contrast curve calculation, and table and plot
generation. SImMER supports observations taken with the ShARCS camera on the
Shane 3-m telescope and the PHARO camera on the Hale 5.1-m telescope. The
modular nature of SImMER allows users to extend the pipeline to accommodate
additional instruments with relative ease. One of the core functions of the
pipeline is its image registration module, which is flexible enough to reduce
saturated images and images of similar-brightness, resolved stellar binaries.
Furthermore, SImMER can compute contrast curves for reduced images and produce
publication-ready plots. The code is developed online at
\url{https://github.com/arjunsavel/SImMER} and is both pip- and
conda-installable. We develop tutorials and documentation alongside the code
and host them online. With SImMER, we aim to provide a community resource for
accurate and reliable data reduction and analysis.Comment: 12 pages, 5 figures. Accepted to PAS
âStill good lifeâ: On the value of reuse and distributive labor in âdepletedâ rural Maine
This article explores the production of wealth through distributive labor in Maine\u27s secondhand economy. While reuse is often associated with economic disadvantage, our research complicates that perspective. The labor required to reclaim, repair, redistribute, and reuse secondhand goods provides much more than a means of living in places left behind by international capitalism, but the value generated by this work is persistently discounted by dominant economic logics. On the basis of semistructured interviews, participant observation, and statewide surveys with reuse market participants in Maine, we find that the relational value of reuse, produced through caring, flexible, distributive labor, is especially significant. We argue that paying attention to the practices, politics, and value of distribution is critical for understanding wealth in communities perceived to have been left behind by global capitalist systems, particularly as wage labor opportunities and natural resources grow increasingly scarce
TESS Hunt for Young and Maturing Exoplanets (THYME) VII : Membership, rotation, and lithium in the young cluster Group-X and a new young exoplanet
The public, all-sky surveys Gaia and TESS provide the ability to identify new
young associations and determine their ages. These associations enable study of
planetary evolution by providing new opportunities to discover young
exoplanets. A young association was recently identified by Tang et al. and
F{\"u}rnkranz et al. using astrometry from Gaia (called "Group-X" by the
former). In this work, we investigate the age and membership of this
association; and we validate the exoplanet TOI 2048 b, which was identified to
transit a young, late G dwarf in Group-X using photometry from TESS. We first
identified new candidate members of Group-X using Gaia EDR3 data. To infer the
age of the association, we measured rotation periods for candidate members
using TESS data. The clear color--period sequence indicates that the
association is the same age as the Myr-old NGC 3532. We obtained
optical spectra for candidate members that show lithium absorption consistent
with this young age. Further, we serendipitously identify a new, small
association nearby Group-X, which we call MELANGE-2. Lastly, we statistically
validate TOI 2048 b, which is \rearth\ radius planet on a 13.8-day
orbit around its 300 Myr-old host star.Comment: Revised to correct error in reported planet radius (original: 2.1
Earth radii, corrected: 2.6 Earth radii) and units for planetary radius ratio
entries in Table 8. All data tables available open-access with the AJ articl
African-specific alleles modify risk for asthma at the 17q12-q21 locus in African Americans
BACKGROUND: Asthma is the most common chronic disease in children, occurring at higher frequencies and with more severe disease in children with African ancestry.
METHODS: We tested for association with haplotypes at the most replicated and significant childhood-onset asthma locus at 17q12-q21 and asthma in European American and African American children. Following this, we used whole-genome sequencing data from 1060 African American and 100 European American individuals to identify novel variants on a high-risk African American-specific haplotype. We characterized these variants in silico using gene expression and ATAC-seq data from airway epithelial cells, functional annotations from ENCODE, and promoter capture (pc)Hi-C maps in airway epithelial cells. Candidate causal variants were then assessed for correlation with asthma-associated phenotypes in African American children and adults.
RESULTS: Our studies revealed nine novel African-specific common variants, enriched on a high-risk asthma haplotype, which regulated the expression of GSDMA in airway epithelial cells and were associated with features of severe asthma. Using ENCODE annotations, ATAC-seq, and pcHi-C, we narrowed the associations to two candidate causal variants that are associated with features of T2 low severe asthma.
CONCLUSIONS: Previously unknown genetic variation at the 17q12-21 childhood-onset asthma locus contributes to asthma severity in individuals with African ancestries. We suggest that many other population-specific variants that have not been discovered in GWAS contribute to the genetic risk for asthma and other common diseases
The TESS Grand Unified Hot Jupiter Survey. I. Ten TESS Planets
We report the discovery of ten short-period giant planets (TOI-2193A b,
TOI-2207 b, TOI-2236 b, TOI-2421 b, TOI-2567 b, TOI-2570 b, TOI-3331 b,
TOI-3540A b, TOI-3693 b, TOI-4137 b). All of the planets were identified as
planet candidates based on periodic flux dips observed by NASA's Transiting
Exoplanet Survey Satellite (TESS). The signals were confirmed to be from
transiting planets using ground-based time-series photometry, high angular
resolution imaging, and high-resolution spectroscopy coordinated with the TESS
Follow-up Observing Program. The ten newly discovered planets orbit relatively
bright F and G stars (,~ between 4800 and 6200 K).
The planets' orbital periods range from 2 to 10~days, and their masses range
from 0.2 to 2.2 Jupiter masses. TOI-2421 b is notable for being a Saturn-mass
planet and TOI-2567 b for being a ``sub-Saturn'', with masses of and Jupiter masses, respectively. In most cases, we
have little information about the orbital eccentricities. Two exceptions are
TOI-2207 b, which has an 8-day period and a detectably eccentric orbit (), and TOI-3693 b, a 9-day planet for which we can set an upper
limit of . The ten planets described here are the first new planets
resulting from an effort to use TESS data to unify and expand on the work of
previous ground-based transit surveys in order to create a large and
statistically useful sample of hot Jupiters.Comment: 44 pages, 15 tables, 21 figures; revised version submitted to A
Another Shipment of Six Short-Period Giant Planets from TESS
We present the discovery and characterization of six short-period, transiting
giant planets from NASA's Transiting Exoplanet Survey Satellite (TESS) --
TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642),
TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467).
All six planets orbit bright host stars (8.9 <G< 11.8, 7.7 <K< 10.1). Using a
combination of time-series photometric and spectroscopic follow-up observations
from the TESS Follow-up Observing Program (TFOP) Working Group, we have
determined that the planets are Jovian-sized (R = 1.00-1.45 R),
have masses ranging from 0.92 to 5.35 M, and orbit F, G, and K stars
(4753 T 7360 K). We detect a significant orbital eccentricity
for the three longest-period systems in our sample: TOI-2025 b (P = 8.872 days,
= ), TOI-2145 b (P = 10.261 days, =
), and TOI-2497 b (P = 10.656 days, =
). TOI-2145 b and TOI-2497 b both orbit subgiant host
stars (3.8 g 4.0), but these planets show no sign of inflation
despite very high levels of irradiation. The lack of inflation may be explained
by the high mass of the planets; M (TOI-2145
b) and M (TOI-2497 b). These six new discoveries
contribute to the larger community effort to use {\it TESS} to create a
magnitude-complete, self-consistent sample of giant planets with
well-determined parameters for future detailed studies.Comment: 20 Pages, 6 Figures, 8 Tables, Accepted by MNRA
Comprehensive Pan-Genomic Characterization of Adrenocortical Carcinoma
SummaryWe describe a comprehensive genomic characterization of adrenocortical carcinoma (ACC). Using this dataset, we expand the catalogue of known ACC driver genes to include PRKAR1A, RPL22, TERF2, CCNE1, and NF1. Genome wide DNA copy-number analysis revealed frequent occurrence of massive DNA loss followed by whole-genome doubling (WGD), which was associated with aggressive clinical course, suggesting WGD is a hallmark of disease progression. Corroborating this hypothesis were increased TERT expression, decreased telomere length, and activation of cell-cycle programs. Integrated subtype analysis identified three ACC subtypes with distinct clinical outcome and molecular alterations which could be captured by a 68-CpG probe DNA-methylation signature, proposing a strategy for clinical stratification of patients based on molecular markers
- âŠ