735 research outputs found
Shock testing of a nitrogen tank (Cryo diffusion type 220 VLR) on the middle weight shock stand
Results of vertical and horizontal shock tests on type 200 VLR nitrogen tank are given
Traitor: associating concepts using the world wide web
We use Common Crawl's 25TB data set of web pages to construct a database of associated concepts using Hadoop. The database can be queried through a web application with two query interfaces. A textual interface allows searching for similarities and differences between multiple concepts using a query language similar to set notation, and a graphical interface allows users to visualize similarity relationships of concepts in a force directed graph
The fast transient sky with Gaia
The ESA Gaia satellite scans the whole sky with a temporal sampling ranging
from seconds and hours to months. Each time a source passes within the Gaia
field of view, it moves over 10 CCDs in 45 s and a lightcurve with 4.5 s
sampling (the crossing time per CCD) is registered. Given that the 4.5 s
sampling represents a virtually unexplored parameter space in optical time
domain astronomy, this data set potentially provides a unique opportunity to
open up the fast transient sky. We present a method to start mining the wealth
of information in the per CCD Gaia data. We perform extensive data filtering to
eliminate known on-board and data processing artefacts, and present a
statistical method to identify sources that show transient brightness
variations on ~2 hours timescales. We illustrate that by using the Gaia
photometric CCD measurements, we can detect transient brightness variations
down to an amplitude of 0.3 mag on timescales ranging from 15 seconds to
several hours. We search an area of ~23.5 square degrees on the sky, and find
four strong candidate fast transients. Two candidates are tentatively
classified as flares on M-dwarf stars, while one is probably a flare on a giant
star and one potentially a flare on a solar type star. These classifications
are based on archival data and the timescales involved. We argue that the
method presented here can be added to the existing Gaia Science Alerts
infrastructure for the near real-time public dissemination of fast transient
events.Comment: 10 pages, 5 figures and 5 tables; MNRAS in pres
Survival following surgical treatment for anorectal melanoma seems similar for local excision and extensive resection regardless of nodal involvement
Background: Anorectal melanoma is a rare malignancy with a dismal prognosis. The purpose of this study was to investigate whether the survival per stage is influenced by the surgical approaches (local excision or extensive resection), to assess prognostic factors of survival, and to answer the question whether the practiced surgical approaches changed over time. Methods: Dutch cancer registry organizations (IKNL and PALGA) were queried for all patients with a diagnosis of anorectal melanoma (1989-2019). Patients with disseminated disease at diagnosis were excluded. Survival outcomes were compared for the two surgical approaches stratified by stage (clinical node negative (cN0) and clinical node positive (cN+)) and date of diagnosis. Results: A total of 103 patients were included in this study. In both cN0 and cN+ patients the surgical strategy did not significantly influence survival (cN0: 21.7% 5-year survival, median 25 months for local excision versus 13.7% 5-year survival, median 17 months for extensive resection (p = 0.228), cN+: 11.1% 5-year survival for local excision, median 17 months versus 8.7% 5-year survival, median 14 months for extensive resection (p = 0.741)). Stage and date of diagnosis showed to be prognostic factors of survival. The ratio between the two surgical approaches was unchanged over three decades. Conclusions: Extensive resection does not seem to improve survival in both cN0 and cN+ anorectal melanoma patients compared to local excision. However in the past three decades no shift towards local excision has been found. cN+ stage and an older date of diagnosis are predictors for worse survival
Effects of circuit training as alternative to usual physiotherapy after stroke: randomised controlled trial
Objective To analyse the effect of task oriented circuit training compared with usual physiotherapy in terms of self reported walking competency for patients with stroke discharged from a rehabilitation centre to their own home
Reoperation after colorectal surgery is an independent predictor of the 1-year mortality rate
BACKGROUND: Comparative evaluation of surgical quality among hospitals must improve outcome and efficiency, and reduce medical costs. Reoperation after colorectal surgery is a consequence of surgical complications and therefore considered a quality-of-care indicator. With respect to the mortality rate, the 1-year mortality may be a more meaningful figure than in-hospital mortality, because it also reflects the impact of surgical complications beyond discharge. OBJECTIVE: The aim of our study was to evaluate the 1-year mortality after colorectal surgery and to identify predicting factors. DESIGN: This study was a retrospective analysis from our colorectal surgery database. PATIENTS: All patients who underwent elective colorectal surgery from 2005 to 2008 were included. MAIN OUTCOME MEASURES: Both univariate and multivariate analysis were performed to identify predicting factors. The following variables were analyzed: age, operative risk according to the ASA class, Charlson-Age Comorbidity Index, indication for and type of resection, primary anastomosis, tumor staging, anastomotic leakage, and reoperation. RESULTS: For 743 consecutive patients, the 1-year mortality rate was 6.9%. Patients were operated on mainly because of colorectal cancer (n = 537; 72%). The rate of reoperation and in-hospital mortality was 12.8% and 2.4%. Univariate survival analysis demonstrated that ASA class, age, Charlson-Age Comorbidity Index, reoperation, and stage of disease were independent predictors of 1-year mortality. Multivariate analysis showed that ASA class (P = .020; HR 1.69), age (P = .015; HR 2.08) and reoperation (P = .001; HR 2.72) are directly correlated with 1-year mortality. LIMITATIONS: Both patients with benign diseases and colorectal cancer are included. Furthermore, no clear guidelines on whether to perform a reoperation were available. CONCLUSION: One-year mortality after colorectal surgery is independently predicted by ASA class, age, and reoperation. Our results underline the value of the 1-year mortality rate and the reoperation rate as parameters for quality assessment in colorectal surgery
The Tully-Fisher Relation and H_not
The use of the Tully-Fisher (TF) relation for the determination of the Hubble
Constant relies on the availability of an adequate template TF relation and of
reliable primary distances. Here we use a TF template relation with the best
available kinematical zero-point, obtained from a sample of 24 clusters of
galaxies extending to cz ~ 9,000 km/s, and the most recent set of Cepheid
distances for galaxies fit for TF use. The combination of these two ingredients
yields H_not = 69+/-5 km/(s Mpc). The approach is significantly more accurate
than the more common application with single cluster (e.g. Virgo, Coma)
samples.Comment: 10 pages, including 2 figures and 1 table; uses AAS LaTex. Submitted
to ApJ Letter
Rijafstand als de sleutel tot efficiënt onkruidbeheer in de biologische suikerbietenteelt
In de biologische bietenteelt kan de hoeveelheid arbeid voor handmatig wieden behoorlijk oplopen. In proeven met variabele rijafstand is nagegaan in hoeverre het aantal wieduren te verkleinen is door een nauwere (betere onkruidonderdrukking door het gewas) of juist ruimere (groter aandeel mechanische bestrijding) rijafstand te gebruiken dan de nu algemeen gangbare vijftig centimeter. Verruiming van de rijafstand komt uit het onderzoek als meest perspectiefvolle optie naar voren en biedt de mogelijkheid het handwerk met ruim 30% te vermindere
Surgical treatment of anorectal melanoma:a systematic review and meta-analysis
BACKGROUND: Anorectal melanoma is a rare neoplasm with a poor prognosis. The surgical approaches for anorectal melanoma can be categorized into local excision (procedures without lymph node removal and preservation of the rectum) and extensive resection (procedures with rectum and pararectal lymph node removal). The aim of this systematic review and meta-analysis was to compare the survival of patients who underwent extensive resection with that of patients who underwent local excision, stratifying patients according to tumour stage. METHODS: A literature review was performed according to PRISMA guidelines by searching MEDLINE/PubMed for manuscripts published until March 2021. Studies comparing survival outcomes in patients with anorectal melanoma who underwent local excision versus extensive resection were screened for eligibility. Meta-analysis was performed for overall survival after the different surgical approaches, stratified by tumour stage. RESULTS: There were 347 studiesidentified of which 34 were included for meta-analysis with a total of 1858 patients. There was no significant difference in overall survival between the surgical approaches in patients per stage (stage I odds ratio 1.30 (95 per cent c.i. 0.62 to 2.72, P = 0.49); stage II odds ratio 1.61 (95 per cent c.i. 0.62 to 4.18, P = 0.33); stage I–III odds ratio 1.19 (95 per cent c.i. 0.83 to 1.70, P = 0.35). Subgroup analyses were conducted for the time intervals (<2000, 2001–2010 and 2011–2021) and for continent of study origin. Subgroup analysis for time interval and continent of origin also showed no statistically significant differences in overall survival. CONCLUSION: No significant survival benefit exists for patients with anorectal melanoma treated with local excision or extensive resection, independent of tumour stage
Constraining the nature of the accreting binary in CXOGBS J174623.5-310550
We report optical and infrared observations of the X-ray source CXOGBS
J174623.5-310550. This Galactic object was identified as a potential quiescent
low-mass X-ray binary accreting from an M-type donor on the basis of optical
spectroscopy and the broad Halpha emission line. The analysis of X-shooter
spectroscopy covering 3 consecutive nights supports an M2/3-type spectral
classification. Neither radial velocity variations nor rotational broadening is
detected in the photospheric lines. No periodic variability is found in I- and
r'-band light curves. We derive r' = 20.8, I = 19.2 and Ks = 16.6 for the
optical and infrared counterparts with the M-type star contributing 90% to the
I-band light. We estimate its distance to be 1.3-1.8 kpc. The lack of radial
velocity variations implies that the M-type star is not the donor star in the
X-ray binary. This could be an interloper or the outer body in a hierarchical
triple. We constrain the accreting binary to be a < 2.2 hr orbital period
eclipsing cataclysmic variable or a low-mass X-ray binary lying in the
foreground of the Galactic Bulge.Comment: (9 pages, 5 figures, accepted for publication in MNRAS
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