456 research outputs found
Kaczynski is to Walden as a Predator Drone is to Batman.
I can see an image of Darth Vader making graphs that describe the Singularity with his left hand while tightly rendering Odysseus gouging out the eye of Polyphemus with his right hand. At the same time Vader is reciting philosophy and critical theory in both English and binary code through a speaker in a mask that filters his true voice. The written portion of my thesis provides perspective into my artistic practice while elaborating on the ideas behind the two-dimensional allegorical panel paintings from my thesis exhibition, Kaczynski is to Walden as a Predator Drone is to Batman. I use symbols to construct imagery that aims to provoke thought surrounding our current relationships with technology
Transcript for Episode 36: Beyond Montana: Tom Judge\u27s 2nd Term Builds International Trade and Sustainable Growth (THIS TRANSCRIPT IS NOT YET AVAILABLE; WILL BE INSTALLED WHEN AVAILABLE)
https://digitalcommons.mtech.edu/crucible_transcriptions/1035/thumbnail.jp
Liger for Next Generation Keck AO: Filter Wheel and Pupil Design
Liger is a next-generation near-infrared imager and integral field
spectrograph (IFS) for the W.M. Keck Observatory designed to take advantage of
the Keck All-Sky Precision Adaptive Optics (KAPA) upgrade. Liger will operate
at spectral resolving powers between R4,000 - 10,000 over a wavelength
range of 0.8-2.4m. Liger takes advantage of a sequential imager and
spectrograph design that allows for simultaneous observations between the two
channels using the same filter wheel and cold pupil stop. We present the design
for the filter wheels and pupil mask and their location and tolerances in the
optical design. The filter mechanism is a multi-wheel design drawing from the
heritage of the current Keck/OSIRIS imager single wheel design. The Liger
multi-wheel configuration is designed to allow future upgrades to the number
and range of filters throughout the life of the instrument. The pupil mechanism
is designed to be similarly upgradeable with the option to add multiple pupil
mask options. A smaller wheel mechanism allows the user to select the desired
pupil mask with open slots being designed in for future upgrade capabilities.
An ideal pupil would match the shape of the image formed of the primary and
would track its rotation. For different pupil shapes without tracking we model
the additional exposure time needed to achieve the same signal to noise of an
ideal pupil and determine that a set of fixed masks of different shapes
provides a mechanically simpler system with little compromise in performance.Comment: 9 pages, 7 figures, 1 tabl
Liger for Next Generation Keck Adaptive Optics: Opto-Mechanical Dewar for Imaging Camera and Slicer
Liger is a next generation adaptive optics (AO) fed integral field
spectrograph (IFS) and imager for the W. M. Keck Observatory. This new
instrument is being designed to take advantage of the upgraded AO system
provided by Keck All-Sky Precision Adaptive-optics (KAPA). Liger will provide
higher spectral resolving power (R4,000-10,000), wider wavelength
coverage (0.8-2.4 m), and larger fields of view than any current
IFS. We present the design and analysis for a custom-made dewar chamber for
characterizing the Liger opto-mechanical system. This dewar chamber is designed
to test and assemble the Liger imaging camera and slicer IFS components while
being adaptable for future experiments. The vacuum chamber will operate below
Torr with a cold shield that will be kept below 90 K. The dewar test
chamber will be mounted to an optical vibration isolation platform and further
isolated from the cryogenic and vacuum systems with bellows. The cold head and
vacuums will be mounted to a custom cart that will also house the electronics
and computer that interface with the experiment. This test chamber will provide
an efficient means of calibrating and characterizing the Liger instrument and
performing future experiments.Comment: 8 pages, 6 figure
An overview of the NIRSPEC upgrade for the Keck II telescope
NIRSPEC is a 1-5 micron echelle spectrograph in use on the Keck II Telescope
since 1999. The spectrograph is capable of both moderate (R~2,000) and high
(R~25,000) resolution observations and has been a workhorse instrument across
many astronomical fields, from planetary science to extragalactic observations.
In the latter half of 2018, we will upgrade NIRSPEC to improve the sensitivity
and stability of the instrument and increase its lifetime. The major components
of the upgrade include replacing the spectrometer and slit-viewing camera
detectors with Teledyne H2RG arrays and replacing all transputer-based
electronics. We present detailed design, testing, and analysis of the upgraded
instrument, including the finalized optomechanical design of the new 1-5 micron
slit-viewing camera, final alignment and assembly of the science array,
electronics systems, and updated software design.Comment: Proceedings of the 2018 SPIE Astronomical Telescopes &
Instrumentatio
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Safety and Acceptability of Esophageal Cytosponge Cell Collection Device in a Pooled Analysis of Data From Individual Patients.
BACKGROUND & AIMS: Diagnosis and surveillance of Barrett's esophagus (BE) and eosinophilic esophagitis (EoE) have become emerging public health issues. Cytosponge is a novel, minimally invasive esophageal cell collection device. We aimed to assess the data on safety and acceptability of this device. METHODS: We performed a patient-level review of 5 prospective trials assessing Cytosponge performance in patients with reflux disease, BE and EoE in primary and secondary care. Acceptability of Cytosponge and subsequent endoscopy were recorded with visual analogue scale (VAS), wherein 0 and 10 denoted lowest and highest acceptability. Median VAS scores were compared using a Mann-Whitney test. The number of attempts, failures in swallowing the device and occurrence of adverse events were analyzed. Risk factors for failure in swallowing were analyzed using a multivariate regression model. RESULTS: In total, 2672 Cytosponge procedures were performed, in 2418 individuals from 2008 through 2017. There were 2 adverse events related to the device: a minor pharyngeal bleed and a case of detachment (<1:2000). The median acceptability score for the Cytosponge was 6.0 (interquartile range [IQR], 5.0-8.0), which was higher than the score for endoscopy without sedation (median 5.0; IQR, 3.0-7.0; P < .001) and lower than the score for endoscopy with sedation (median 8.0; IQR, 5.0-9.0; P < .001). Nearly all patients (91.1%) successfully swallowed the Cytosponge, most on the first attempt (90.1%). Failure to swallow the device was more likely to occur in secondary care (odds ratio, 5.13; 95% CI, 1.48-17.79; P < .01). CONCLUSIONS: The Cytosponge test is a safe procedure with good acceptability ratings in a variety of health care settings
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A high-resolution map of human evolutionary constraint using 29 mammals.
The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ∼4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ∼60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease
Risk stratification of Barrett's oesophagus using a non-endoscopic sampling method coupled with a biomarker panel: a cohort study
Background Barrett's oesophagus predisposes to adenocarcinoma. However, most patients with Barrett's oesophagus will not progress and endoscopic surveillance is invasive, expensive, and fraught by issues of sampling bias and the subjective assessment of dysplasia. We investigated whether a non-endoscopic device, the Cytosponge, could be coupled with clinical and molecular biomarkers to identify a group of patients with low risk of progression suitable for non-endoscopic follow-up. Methods In this multicentre cohort study (BEST2), patients with Barrett's oesophagus underwent the Cytosponge test before their surveillance endoscopy. We collected clinical and demographic data and tested Cytosponge samples for a molecular biomarker panel including three protein biomarkers (P53, c-Myc, and Aurora kinase A), two methylation markers (MYOD1 and RUNX3), glandular atypia, and TP53 mutation status. We used a multivariable logistic regression model to compute the conditional probability of dysplasia status. We selected a simple model with high classification accuracy and applied it to an independent validation cohort. The BEST2 study is registered with ISRCTN, number 12730505. Findings The discovery cohort consisted of 468 patients with Barrett's oesophagus and intestinal metaplasia. Of these, 376 had no dysplasia and 22 had high-grade dysplasia or intramucosal adenocarcinoma. In the discovery cohort, a model with high classification accuracy consisted of glandular atypia, P53 abnormality, and Aurora kinase A positivity, and the interaction of age, waist-to-hip ratio, and length of the Barrett's oesophagus segment. 162 (35%) of 468 of patients fell into the low-risk category and the probability of being a true non-dysplastic patient was 100% (99% CI 96–100) and the probability of having high-grade dysplasia or intramucosal adenocarcinoma was 0% (0–4). 238 (51%) of participants were classified as of moderate risk; the probability of having high-grade dysplasia was 14% (9–21). 58 (12%) of participants were classified as high-risk; the probability of having non-dysplastic endoscopic biopsies was 13% (5–27), whereas the probability of having high-grade dysplasia or intramucosal adenocarcinoma was 87% (73–95). In the validation cohort (65 patients), 51 were non-dysplastic and 14 had high-grade dysplasia. In this cohort, 25 (38%) of 65 patients were classified as being low-risk, and the probability of being non-dysplastic was 96·0% (99% CI 73·80–99·99). The moderate-risk group comprised 27 non-dysplastic and eight high-grade dysplasia cases, whereas the high-risk group (8% of the cohort) had no non-dysplastic cases and five patients with high-grade dysplasia. Interpretation A combination of biomarker assays from a single Cytosponge sample can be used to determine a group of patients at low risk of progression, for whom endoscopy could be avoided. This strategy could help to avoid overdiagnosis and overtreatment in patients with Barrett's oesophagus. Funding Cancer Research UK
Keck Planet Imager and Characterizer: A dedicated single-mode fiber injection unit for high resolution exoplanet spectroscopy
The Keck Planet Imager and Characterizer (KPIC) is a purpose-built instrument to demonstrate new tech- nological and instrumental concepts initially developed for the exoplanet direct imaging field. Located downstream of the current Keck II adaptive optic system, KPIC contains a fiber injection unit (FIU) capable of combining the high-contrast imaging capability of the adaptive optic system with the high dispersion spectroscopy capability of the current Keck high resolution infrared spectrograph (NIRSPEC). Deployed at Keck in September 2018, this instrument has already been used to acquire high resolution spectra (R < 35, 000) of multiple targets of interest. In the near term, it will be used to spectrally characterize known directly imaged exoplanets and low-mass brown dwarf companions visible in the northern hemisphere with a spectral resolution high enough to enable spin and planetary radial velocity measurements as well as Doppler imaging of atmospheric weather phenomena. Here we present the design of the FIU, the unique calibration procedures needed to operate a single-mode fiber instrument and the system performance
An Improved Canine Genome and a Comprehensive Catalogue of Coding Genes and Non-Coding Transcripts
The domestic dog, Canis familiaris, is a well-established model system for mapping trait and disease loci. While the original draft sequence was of good quality, gaps were abundant particularly in promoter regions of the genome, negatively impacting the annotation and study of candidate genes. Here, we present an improved genome build, canFam3.1, which includes 85 MB of novel sequence and now covers 99.8% of the euchromatic portion of the genome. We also present multiple RNA-Sequencing data sets from 10 different canine tissues to catalog ∼175,000 expressed loci. While about 90% of the coding genes previously annotated by EnsEMBL have measurable expression in at least one sample, the number of transcript isoforms detected by our data expands the EnsEMBL annotations by a factor of four. Syntenic comparison with the human genome revealed an additional ∼3,000 loci that are characterized as protein coding in human and were also expressed in the dog, suggesting that those were previously not annotated in the EnsEMBL canine gene set. In addition to ∼20,700 high-confidence protein coding loci, we found ∼4,600 antisense transcripts overlapping exons of protein coding genes, ∼7,200 intergenic multi-exon transcripts without coding potential, likely candidates for long intergenic non-coding RNAs (lincRNAs) and ∼11,000 transcripts were reported by two different library construction methods but did not fit any of the above categories. Of the lincRNAs, about 6,000 have no annotated orthologs in human or mouse. Functional analysis of two novel transcripts with shRNA in a mouse kidney cell line altered cell morphology and motility. All in all, we provide a much-improved annotation of the canine genome and suggest regulatory functions for several of the novel non-coding transcripts
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