39 research outputs found
The Optical-infrared Extinction Curve and Its Variation in the Milky Way
The dust extinction curve is a critical component of many observational programs and an important diagnostic of the physics of the interstellar medium. Here we present new measurements of the dust extinction curve and its variation toward tens of thousands of stars, a hundred-fold larger sample than in existing detailed studies. We use data from the APOGEE spectroscopic survey in combination with ten-band photometry from Pan-STARRS1, the Two Micron All-Sky Survey, and Wide-field Infrared Survey Explorer. We find that the extinction curve in the optical through infrared is well characterized by a one-parameter family of curves described by R(V). The extinction curve is more uniform than suggested in past works, with , and with less than one percent of sight lines having . Our data and analysis have revealed two new aspects of Galactic extinction: first, we find significant, wide-area variations in R(V) throughout the Galactic plane. These variations are on scales much larger than individual molecular clouds, indicating that R(V) variations must trace much more than just grain growth in dense molecular environments. Indeed, we find no correlation between R(V) and dust column density up to . Second, we discover a strong relationship between R(V) and the far-infrared dust emissivity
Correlation dynamics between electrons and ions in the fragmentation of D molecules by short laser pulses
We studied the recollision dynamics between the electrons and D ions
following the tunneling ionization of D molecules in an intense short pulse
laser field. The returning electron collisionally excites the D ion to
excited electronic states from there D can dissociate or be further
ionized by the laser field, resulting in D + D or D + D,
respectively. We modeled the fragmentation dynamics and calculated the
resulting kinetic energy spectrum of D to compare with recent experiments.
Since the recollision time is locked to the tunneling ionization time which
occurs only within fraction of an optical cycle, the peaks in the D kinetic
energy spectra provides a measure of the time when the recollision occurs. This
collision dynamics forms the basis of the molecular clock where the clock can
be read with attosecond precision, as first proposed by Corkum and coworkers.
By analyzing each of the elementary processes leading to the fragmentation
quantitatively, we identified how the molecular clock is to be read from the
measured kinetic energy spectra of D and what laser parameters be used in
order to measure the clock more accurately.Comment: 13 pages with 14 figure
Could Fidicina mannifera (Hemiptera: Cicadoidea: Fidicinini) promote a resource pulse in two Brazilian Cerrado vegetation classes?
Neuroblastoma between 1990 and 2014 in the Netherlands: Increased incidence and improved survival of high-risk neuroblastoma
Purpose: Long-term trends in neuroblastoma incidence and survival in unscreened populations are unknown. We explored trends in incidence, stage at diagnosis, treatment and survival of neuroblastoma in the Netherlands from 1990 to 2014. Methods: The Netherlands Cancer Registry provided data on all patients aged <18 years diagnosed with a neuroblastoma. Trends in incidence and stage were evaluated by calculating the average annual percentage change (AAPC). Univariate and multivariable survival analyses were performed for stage 4 disease to test whether changes in treatment are associated with survival. Results: Of the 593 newly diagnosed neuroblastoma cases, 45% was <18 months of age at diagnosis and 52% had stage 4 disease. The age-standardized incidence rate for stage 4 disease increased at all ages from 3.2 to 5.3 per million children per year (AAPC + 2.9%, p <. 01). This increase was solely for patients â„18 months old (3.0â5.4; AAPC +3.3%, p =. 01). Five-year OS of all patients increased from 44 ± 5% to 61 ± 4% from 1990 to 2014 (p <. 01) and from 19 ± 6% to 44 ± 6% (p <. 01) for patients with stage 4 disease. Multivariable analysis revealed that high-dose chemotherapy followed by autologous stem cell rescue and anti-GD2-based immunotherapy were associated with this survival increase (HR 0.46, p <. 01 and HR 0.37, p <. 01, respectively). Conclusion: Incidence of stage 4 neuroblastoma increased exclusively in patients aged â„18 months since 1990, whereas the incidence of other stages remained stable. The 5-year OS of stage 4 patients improved, mostly due to the introduction of high-dose chemotherapy followed by stem cell rescue and immunotherapy
ANTARES: the first undersea neutrino telescope
The ANTARES Neutrino Telescope was completed in May 2008 and is the first
operational Neutrino Telescope in the Mediterranean Sea. The main purpose of
the detector is to perform neutrino astronomy and the apparatus also offers
facilities for marine and Earth sciences. This paper describes the design, the
construction and the installation of the telescope in the deep sea, offshore
from Toulon in France. An illustration of the detector performance is given
A computer-based guideline implementation system for cardiac rehabilitation screening
The Netherlands heart foundation recently released a new cardiac rehabilitation guideline. Concurrent with its development, a decision support system (DSS) was built to assist professionals in implementing the guideline in practice. The DSS was evaluated during a 6-week pilot study in four cardiac rehabilitation centers. The number of patients enrolled in the DSS during the pilot study was 134. Adherence to the guidelines on a patient level was 83% for rehabilitation goals, and 68% for rehabilitation therapies. After the pilot study several new functionalities were added to the system while other DSS parts of the system were slightly changed based on user advice. Currently, a large-scale cluster randomized trial is conducted in 38 Dutch hospitals to rigorously assess the effect of the DSS on guideline adherenc
A computer-based guideline implementation system for cardiac rehabilitation screening
The Netherlands heart foundation recently released a new cardiac rehabilitation guideline. Concurrent with its development, a decision support system (DSS) was built to assist professionals in implementing the guideline in practice. The DSS was evaluated during a 6-week pilot study in four cardiac rehabilitation centers. The number of patients enrolled in the DSS during the pilot study was 134. Adherence to the guidelines on a patient level was 83% for rehabilitation goals, and 68% for rehabilitation therapies. After the pilot study several new functionalities were added to the system while other DSS parts of the system were slightly changed based on user advice. Currently, a large-scale cluster randomized trial is conducted in 38 Dutch hospitals to rigorously assess the effect of the DSS on guideline adherenc
Multidisciplinary Virtual Three-Dimensional Planning of a Forequarter Amputation With Chest Wall Resection
We present the case of a 74-year-old man with a history of a squamous cell carcinoma in the left axilla. The patient underwent a multidisciplinary surgical resection through an extended forequarter amputation with thoracic wall resection and reconstruction. With regard to the complexity of the case, three-dimensional virtual realityâbased patient-specific reconstructions were used as a supplemental tool to conventional computed tomography imaging to plan the procedure. With this report, we aim to stimulate further research to improve and automate the workflow and to bring virtual and augmented reality reconstructions into the surgical theater of the future
A dynamic Bayesian network for diagnosing ventilator-associated pneumonia in ICU patients
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