17,858 research outputs found
Studying the Kinematics of Faint Stellar Populations with the Planetary Nebula Spectrograph
Galaxies are faint enough when one observes just their light distributions,
but in studying their full dynamical structure the stars are spread over the
six dimensions of phase space rather than just the three spatial dimensions,
making their densities very low indeed. This low signal is unfortunate, as
stellar dynamics hold important clues to these systems' life histories, and the
issue is compounded by the fact that the most interesting information comes
from the faintest outer parts of galaxies, where dynamical timescales (and
hence memories of past history) are longest.
To extract this information, we have constructed a special-purpose
instrument, the Planetary Nebula Spectrograph, which observes planetary nebulae
as kinematic tracers of the stellar population, and allows one to study the
stellar dynamics of galaxies down to extremely low surface brightnesses. Here,
we present results from this instrument that illustrate how it can uncover the
nature of low surface-brightness features such as thick disks by studying their
kinematics, and trace faint kinematic populations that are photometrically
undetectable.Comment: 4 pages, 2 figures. To be published in "Hunting for the Dark: The
Hidden Side of Galaxy Formation", eds. V.P. Debattista & C.C. Popescu, AIP
Conf. Se
Capacity building efforts and perceptions for wildlife surveillance to detect zoonotic pathogens: comparing stakeholder perspectives.
BackgroundThe capacity to conduct zoonotic pathogen surveillance in wildlife is critical for the recognition and identification of emerging health threats. The PREDICT project, a component of United States Agency for International Development's Emerging Pandemic Threats program, has introduced capacity building efforts to increase zoonotic pathogen surveillance in wildlife in global 'hot spot' regions where zoonotic disease emergence is likely to occur. Understanding priorities, challenges, and opportunities from the perspectives of the stakeholders is a key component of any successful capacity building program.MethodsA survey was administered to wildlife officials and to PREDICT-implementing in-country project scientists in 16 participating countries in order to identify similarities and differences in perspectives between the groups regarding capacity needs for zoonotic pathogen surveillance in wildlife.ResultsBoth stakeholder groups identified some human-animal interfaces (i.e. areas of high contact between wildlife and humans with the potential risk for disease transmission), such as hunting and markets, as important for ongoing targeting of wildlife surveillance. Similarly, findings regarding challenges across stakeholder groups showed some agreement in that a lack of sustainable funding across regions was the greatest challenge for conducting wildlife surveillance for zoonotic pathogens (wildlife officials: 96% and project scientists: 81%). However, the opportunity for improving zoonotic pathogen surveillance capacity identified most frequently by wildlife officials as important was increasing communication or coordination among agencies, sectors, or regions (100% of wildlife officials), whereas the most frequent opportunities identified as important by project scientists were increasing human capacity, increasing laboratory capacity, and the growing interest or awareness regarding wildlife disease or surveillance programs (all identified by 69% of project scientists).ConclusionsA One Health approach to capacity building applied at local and global scales will have the greatest impact on improving zoonotic pathogen surveillance in wildlife. This approach will involve increasing communication and cooperation across ministries and sectors so that experts and stakeholders work together to identify and mitigate surveillance gaps. Over time, this transdisciplinary approach to capacity building will help overcome existing challenges and promote efficient targeting of high risk interfaces for zoonotic pathogen transmission
The European Large Area ISO Survey - ISOPHOT results using the MPIA-pipeline
The European Large Area ISO Survey (ELAIS) will provide Infrared observations
of 4 regions in the sky with ISO. Around 2000 Infrared sources have been
detected at 7 and 15 microns (with ISOCAM), 90 and 175 microns (with ISOPHOT))
over 13 square degrees of the sky. We present the source extraction pipeline of
the 90 microns ISOPHOT observations, describe and discuss the results obtained
and derive the limits of the ELAIS observational strategy.Comment: 4 pages, 5 figures, to appear in the ISO conference "The Universe as
seen by ISO", 1998, UNESCO, Pari
Comparison of Fermi-LAT and CTA in the region between 10-100 GeV
The past decade has seen a dramatic improvement in the quality of data
available at both high (HE: 100 MeV to 100 GeV) and very high (VHE: 100 GeV to
100 TeV) gamma-ray energies. With three years of data from the Fermi Large Area
Telescope (LAT) and deep pointed observations with arrays of Cherenkov
telescope, continuous spectral coverage from 100 MeV to TeV exists for
the first time for the brightest gamma-ray sources. The Fermi-LAT is likely to
continue for several years, resulting in significant improvements in high
energy sensitivity. On the same timescale, the Cherenkov Telescope Array (CTA)
will be constructed providing unprecedented VHE capabilities. The optimisation
of CTA must take into account competition and complementarity with Fermi, in
particularly in the overlapping energy range 10100 GeV. Here we compare the
performance of Fermi-LAT and the current baseline CTA design for steady and
transient, point-like and extended sources.Comment: Accepted for Publication in Astroparticle Physic
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Pancreas Cancer-Associated Weight Loss.
Unintentional weight loss in patients with pancreatic cancer is highly prevalent and contributes to low therapeutic tolerance, reduced quality of life, and overall mortality. Weight loss in pancreatic cancer can be due to anorexia, malabsorption, and/or cachexia. Proper supportive care can stabilize or reverse weight loss in patients and improve outcomes. We review the literature on supportive care relevant to pancreatic cancer patients, and offer evidence-based recommendations that include expert nutritional assessment, counseling, supportive measures to ensure adequate caloric intake, pancreatic enzyme supplementation, nutritional supplement replacement, orexigenic agents, and exercise. Pancreatic Cancer Action Network-supported initiatives will spearhead the dissemination and adoption of these best supportive care practices. IMPLICATIONS FOR PRACTICE: Weight loss in pancreatic cancer patients is endemic, as 85% of pancreatic cancer patients meet the classic definition of cancer cachexia. Despite its significant prevalence and associated morbidity, there is no established approach to this disease entity. It is believed that this is due to an important knowledge gap in understanding the underlying biology and lack of optimal treatment approaches. This article reviews the literature regarding pancreas cancer-associated weight loss and establishes a new framework from which to view this complex clinical problem. An improved approach and understanding will help educate clinicians, improve clinical care, and provide more clarity for future clinical investigation
Spectroscopic characterisation of CARMENES target candidates from FEROS, CAFE and HRS high-resolution spectra
CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with
Near-infrared and optical Echelle Spectrographs) started a new planet survey on
M-dwarfs in January this year. The new high-resolution spectrographs are
operating in the visible and near-infrared at Calar Alto Observatory. They will
perform high-accuracy radial-velocity measurements (goal 1 m s-1) of about 300
M-dwarfs with the aim to detect low-mass planets within habitable zones. We
characterised the candidate sample for CARMENES and provide fundamental
parameters for these stars in order to constrain planetary properties and
understand star-planet systems. Using state-of-the-art model atmospheres
(PHOENIX-ACES) and chi2-minimization with a downhill-simplex method we
determine effective temperature, surface gravity and metallicity [Fe/H] for
high-resolution spectra of around 480 stars of spectral types M0.0-6.5V taken
with FEROS, CAFE and HRS. We find good agreement between the models and our
observed high-resolution spectra. We show the performance of the algorithm, as
well as results, parameter and spectral type distributions for the CARMENES
candidate sample, which is used to define the CARMENES target sample. We also
present first preliminary results obtained from CARMENES spectra
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