6,708 research outputs found
Magnetic Field Uniformity Across the GF 9-2 YSO, L1082C Dense Core, and GF 9 Filamentary Dark Cloud
The orientation of the magnetic field (B-field) in the filamentary dark cloud
GF 9 was traced from the periphery of the cloud into the L1082C dense core that
contains the low-mass, low-luminosity Class 0 young stellar object (YSO) GF 9-2
(IRAS 20503+6006). This was done using SOFIA HAWC+ dust thermal emission
polarimetry (TEP) at 216 um in combination with Mimir near-infrared background
starlight polarimetry (BSP) conducted at H-band (1.6 um) and K-band (2.2 um).
These observations were augmented with published I-band (0.77 um) BSP and
Planck 850 um TEP to probe B-field orientations with offset from the YSO in a
range spanning 6000 AU to 3 pc. No strong B-field orientation change with
offset was found, indicating remarkable uniformity of the B-field from the
cloud edge to the YSO environs. This finding disagrees with weak-field models
of cloud core and YSO formation. The continuity of inferred B-field
orientations for both TEP and BSP probes is strong evidence that both are
sampling a common B-field that uniformly threads the cloud, core, and YSO
region. Bayesian analysis of Gaia DR2 stars matched to the Mimir BSP stars
finds a distance to GF 9 of 270 +/- 10 pc. No strong wavelength dependence of
B-field orientation angle was found, contrary to previous claims.Comment: 18 pages, 6 figures ApJ, accepte
Crawling in Rogue's dungeons with (partitioned) A3C
Rogue is a famous dungeon-crawling video-game of the 80ies, the ancestor of
its gender. Rogue-like games are known for the necessity to explore partially
observable and always different randomly-generated labyrinths, preventing any
form of level replay. As such, they serve as a very natural and challenging
task for reinforcement learning, requiring the acquisition of complex,
non-reactive behaviors involving memory and planning. In this article we show
how, exploiting a version of A3C partitioned on different situations, the agent
is able to reach the stairs and descend to the next level in 98% of cases.Comment: Accepted at the Fourth International Conference on Machine Learning,
Optimization, and Data Science (LOD 2018
Free-form lens model and mass estimation of the high redshift galaxy cluster ACT-CL J0102-4915, "El Gordo"
We examine the massive colliding cluster El Gordo, one of the most massive
clusters at high redshift. We use a free-form lensing reconstruction method
that avoids making assumptions about the mass distribution. We use data from
the RELICS program and identify new multiply lensed system candidates. The new
set of constraints and free-form method provides a new independent mass
estimate of this intriguing colliding cluster. Our results are found to be
consistent with earlier parametric models, indirectly confirming the
assumptions made in earlier work. By fitting a double gNFW profile to the lens
model, and extrapolating to the virial radius, we infer a total mass for the
cluster of M. We
estimate the uncertainty in the mass due to errors in the photometric
redshifts, and discuss the uncertainty in the inferred virial mass due to the
extrapolation from the lens model. We also find in our lens map a mass
overdensity corresponding to the large cometary tail of hot gas, reinforcing
its interpretation as a large tidal feature predicted by hydrodynamical
simulations that mimic El Gordo. Finally, we discuss the observed relation
between the plasma and the mass map, finding that the peak in the projected
mass map may be associated with a large concentration of colder gas, exhibiting
possible star formation. El Gordo is one of the first clusters that will be
observed with JWST, which is expected to unveil new high redshift lensed
galaxies around this interesting cluster, and provide a more accurate
estimation of its mass.Comment: 19 pages, 10 figures. Updated figure
Hepatitis C: an update.
Hepatitis C virus (HCV) infection is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. While current therapeutic options for hepatitis C are limited, recent progress in the understanding of the biology of HCV led to the identification of novel targets for antiviral intervention. In addition, molecular and immunotherapeutic strategies to inhibit HCV replication or gene expression and to enhance the cellular immune response against HCV are being explored. These and other novel antiviral strategies may eventually complement existing therapeutic modalities. Here, we briefly review current concepts of the epidemiology, molecular virology, pathogenesis, natural history, diagnosis, therapy, and prevention of hepatitis C
Phase I multicenter study of combined high-dose ifosfamide and doxorubicin in the treatment of advanced sarcomas
Ifosfamide and doxorubicin are the most active agents in the treatment of sarcomas and are characterized by a marked dose-response relationship. The objective of this study was to determine the maximum tolerated dose (MTD) of both agents in combination under granulocyte-macrophage colony-stimulating factor (GM-CSF) cover. Patients and methods: Thirty-three patients with untreated sarcomas (soft tissue: n = 20; gynecological: n = 11; bone: n = 2) were treated with ifosfamide 12 g/m2 by continuous i.v. infusion over five days and doxorubicin with dose escalation from 50 mg/m2 i.v. bolus divided on two days, then to 60 mg/m2bolus divided on three days. Ifosfamide was reduced to 10 g/m2 and doxorubicin was further escalated up to 90 mg/m2. GM-CSF (5 μg/kg/day subcutaneously) was started 24 hours after chemotherapy and continued for 10 days. Results: The MTD was reached with the combination of ifosfamide at 12 g/m2 and doxorubicin at 60 mg/m2. But with ifosfamide 10 g/m2 and doxorubicin 90 mg/m2 the MTD was not obtained. While severe leukopenia and granulopenia were observed at all-dose levels, severe anemia was more frequently related to the highest dose of ifosfamide. Severe thrombopenia and mucositis were more commonly observed at the highest dose of doxorubicin. Ifosfamide 10 g/m2 and doxorubicin 90 mg/m2 induced WHO grade 4 leukopenia in 58%, grade 3-4 thrombopenia in 42%, and anemia in 31% of cycles. Mucositis was minor in 50% of cycles. The overall response rate among 31 evaluable patients was 55% (95 confidence interval (CI): 36%-73%), with four (13%) complete responders and 13 (42%) partial responders. Response rates based on soft-tissue sarcomas or gynecological sarcomas alone were similar. Ten patients could be treated by elective surgery and/or radiotherapy. The total group of patients reached a median survival of two years, with 25% (SE 8%) survivors after three years. Conclusions: The dose level of ifosfamide 10 g/m2 and doxorubicin 90 mg/m2 with supportive GM-CSF is manageable in a multicenter setting and should be further tested in regular phase II trials, including patients with gynecological and soft-tissue sarcomas. Transient toxicity with myelosup-pression should be accepted in order to obtain a high anti-tumor activity of this regimen and a potential improvement in surviva
Generating Levels That Teach Mechanics
The automatic generation of game tutorials is a challenging AI problem. While
it is possible to generate annotations and instructions that explain to the
player how the game is played, this paper focuses on generating a gameplay
experience that introduces the player to a game mechanic. It evolves small
levels for the Mario AI Framework that can only be beaten by an agent that
knows how to perform specific actions in the game. It uses variations of a
perfect A* agent that are limited in various ways, such as not being able to
jump high or see enemies, to test how failing to do certain actions can stop
the player from beating the level.Comment: 8 pages, 7 figures, PCG Workshop at FDG 2018, 9th International
Workshop on Procedural Content Generation (PCG2018
Discovery of the Vanadium Isotopes
Twenty-four vanadium isotopes have so far been observed; the discovery of
these isotopes is discussed. For each isotope a brief summary of the first
refereed publication, including the production and identification method, is
presented.Comment: to be published in At. Data. Nucl. Data Table
Assessment of processing technologies which may improve the nutritional composition of dairy products – Overview of progress
Among consumers there is a growing demand for food products with a natural nutritional-physiological advantage over comparable conventional products. As part of an EU funded project, ALP is examining the possible impact of processing on nutritionally valuable milk components, using the example of conjugated linoleic acids (CLA). The extent to which processing influences the CLA content of the end product was determined by literature research and own investigations of organic and conventional butter. Furthermore, new chemical, sensory-based and bio crystallization methods were evaluated by ALP and the University of Kassel to determine the oxidation stability of butter. In a further step the storage stability of CLA enriched and conventional butter was examined and the different methods will be compared. As a third objective a process for low-input CLA enrichment of milk fat (with a focus on alpine butter) has been developed. Since the process selected for the work is a physical enrichment process, it is accepted by international organic farming and food groups. Among the many benefits ascribed to CLA, it is believed to be an effective agent against cancer. The demand for foods with properties that promote human health is growing. The dairy industry has the opportunity to meet this demand by developing new dairy products with a nutritional-physiological function for the functional food market
Adiabatic times for Markov chains and applications
We state and prove a generalized adiabatic theorem for Markov chains and
provide examples and applications related to Glauber dynamics of Ising model
over Z^d/nZ^d. The theorems derived in this paper describe a type of adiabatic
dynamics for l^1(R_+^n) norm preserving, time inhomogeneous Markov
transformations, while quantum adiabatic theorems deal with l^2(C^n) norm
preserving ones, i.e. gradually changing unitary dynamics in C^n
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