145 research outputs found
How two business models respond to current chalenges of agrowood production: the case of Brandenburg, Germany
PosterThe agrowood acreage in Brandenburg has increased fifteen-fold since 2008 reaching in 2013 1819ha (Ministerium fĂŒr Infrastruktur und Landwirtschaft 2013) and therefore the leading position of all federal states in Germany. Despite of the constant rise and the chances associated with the production of agrowood, potential producers have to face a wide range of challenges: uncertainties about yields, high initial investments, a fixation of land for the 20 years` lifetime of an agrowood plantation and an irregular cash flow all 3 or 5 years. A non-transparent market in addition to lacking long term experiences and machinery available, affects the decision-making process of potential producers negatively. In Brandenburg this innovative crop, growing even under harsh conditions, matches the unfavorable agricultural conditions (Murach et al. 2008). Our subjects of investigation are the two prevailing business models in the agrowood sector in Brandenburg: comprehensive cooperation agreements and independent farming. They coexist and mutually interact with synergies as well as obstructions. We combine a qualitative method with guided interviews focusing on planting decision making processes with a modeling approach using different risk levels and yield expectations to analyze transaction and opportunity costs of those two models. Thereby the characteristics and effects of the business models are compared and analyzed. Our results show that cooperation agreements have effects on the actor`s decision by motivating farmers to decide in favor of agrowood. They also contribute to an expansion of agrowood acreage accounting for almost 40% of the total area in Brandenburg in 2012 (Ehm 2013). Furthermore cooperation agreements are affirmed by interviewees to overcome economic, trade and machinery related constraints of agrowood, secure long-term incomes and increase creditworthiness of producers. In contrast, independent producers are acknowledged to have the burden of higher risks, but may benefit from governmental support programs, which not apply for contract farmers
ERK1 as a therapeutic target for dendritic cell vaccination against high-grade gliomas
Glioma regression requires the recruitment of potent anti-tumor immune cells into the tumor microenvironment. Dendritic cells (DCs) play a role in immune responses to these tumors. The fact that DC vaccines do not effectively combat high-grade gliomas, however, suggests that DCs need to be genetically modified especially to promote their migration to tumor relevant sites. Previously, we identified extracellular signal-regulated kinase (ERK1) as a regulator of DC immunogenicity and brain autoimmunity. In the present study, we made use of modern magnetic resonance methods to study the role of ERK1 in regulating DC migration and tumor progression in a model of high-grade glioma. We found that ERK1-deficient mice are more resistant to the development of gliomas, and tumor growth in these mice is accompanied by a higher infiltration of leukocytes. ERK1-deficient DCs exhibit an increase in migration that is associated with sustained Cdc42 activation and increased expression of actin-associated cytoskeleton-organizing proteins. We also demonstrated that ERK1 deletion potentiates DC vaccination and provides a survival advantage in high-grade gliomas. Considering the therapeutic significance of these results, we propose ERK1-deleted DC vaccines as an additional means of eradicating resilient tumor cells and preventing tumor recurrence
Multifrequency monitoring of the blazar 0716+714 during the GASP-WEBT-AGILE campaign of 2007
Since the CGRO operation in 1991-2000, one of the primary unresolved
questions about the blazar gamma-ray emission has been its possible correlation
with the low-energy (in particular optical) emission. To help answer this
problem, the Whole Earth Blazar Telescope (WEBT) consortium has organized the
GLAST-AGILE Support Program (GASP) to provide the optical-to-radio monitoring
data to be compared with the gamma-ray detections by the AGILE and GLAST
satellites. This new WEBT project started in early September 2007, just before
a strong gamma-ray detection of 0716+714 by AGILE. We present the GASP-WEBT
optical and radio light curves of this blazar obtained in July-November 2007,
about various AGILE pointings at the source. We construct NIR-to-UV spectral
energy distributions (SEDs), by assembling GASP-WEBT data together with UV data
from the Swift ToO observations of late October. We observe a contemporaneous
optical-radio outburst, which is a rare and interesting phenomenon in blazars.
The shape of the SEDs during the outburst appears peculiarly wavy because of an
optical excess and a UV drop-and-rise. The optical light curve is well sampled
during the AGILE pointings, showing prominent and sharp flares. A future
cross-correlation analysis of the optical and AGILE data will shed light on the
expected relationship between these flares and the gamma-ray events.Comment: 5 pages, 5 figures, to be published in A&A (Letters); revised to
match the final version (changes in Fig. 5 and related text
A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
We present and analyse the WEBT multifrequency observations of 3C 454.3 in
the 2007-2008 observing season, including XMM-Newton observations and near-IR
spectroscopic monitoring, and compare the recent emission behaviour with the
past one. In the optical band we observed a multi-peak outburst in July-August
2007, and other faster events in November 2007 - February 2008. During these
outburst phases, several episodes of intranight variability were detected. A mm
outburst was observed starting from mid 2007, whose rising phase was
contemporaneous to the optical brightening. A slower flux increase also
affected the higher radio frequencies, the flux enhancement disappearing below
8 GHz. The analysis of the optical-radio correlation and time delays, as well
as the behaviour of the mm light curve, confirm our previous predictions,
suggesting that changes in the jet orientation likely occurred in the last few
years. The historical multiwavelength behaviour indicates that a significant
variation in the viewing angle may have happened around year 2000. Colour
analysis reveals a complex spectral behaviour, which is due to the interplay of
different emission components. All the near-IR spectra show a prominent Halpha
emission line, whose flux appears nearly constant. The analysis of the
XMM-Newton data indicates a correlation between the UV excess and the
soft-X-ray excess, which may represent the head and the tail of the big blue
bump, respectively. The X-ray flux correlates with the optical flux, suggesting
that in the inverse-Compton process either the seed photons are synchrotron
photons at IR-optical frequencies or the relativistic electrons are those that
produce the optical synchrotron emission. The X-ray radiation would thus be
produced in the jet region from where the IR-optical emission comes.Comment: 10 pages, 12 figures (7 included in the text, 5 in GIF format),
accepted for publication in A&
WEBT multiwavelength monitoring and XMM-Newton observations of BL Lacertae in 2007-2008. Unveiling different emission components
In 2007-2008 we carried out a new multiwavelength campaign of the Whole Earth
Blazar Telescope (WEBT) on BL Lacertae, involving three pointings by the
XMM-Newton satellite, to study its emission properties. The source was
monitored in the optical-to-radio bands by 37 telescopes. The brightness level
was relatively low. Some episodes of very fast variability were detected in the
optical bands. The X-ray spectra are well fitted by a power law with photon
index of about 2 and photoelectric absorption exceeding the Galactic value.
However, when taking into account the presence of a molecular cloud on the line
of sight, the data are best fitted by a double power law, implying a concave
X-ray spectrum. The spectral energy distributions (SEDs) built with
simultaneous radio-to-X-ray data at the epochs of the XMM-Newton observations
suggest that the peak of the synchrotron emission lies in the near-IR band, and
show a prominent UV excess, besides a slight soft-X-ray excess. A comparison
with the SEDs corresponding to previous observations with X-ray satellites
shows that the X-ray spectrum is extremely variable. We ascribe the UV excess
to thermal emission from the accretion disc, and the other broad-band spectral
features to the presence of two synchrotron components, with their related SSC
emission. We fit the thermal emission with a black body law and the non-thermal
components by means of a helical jet model. The fit indicates a disc
temperature greater than 20000 K and a luminosity greater than 6 x 10^44 erg/s.Comment: 11 pages, 7 figures, accepted for publication in A&
Reviewing the integration of patient data: how systems are evolving in practice to meet patient needs
<p>Abstract</p> <p>Background</p> <p>The integration of Information Systems (IS) is essential to support shared care and to provide consistent care to individuals â patient-centred care. This paper identifies, appraises and summarises studies examining different approaches to integrate patient data from heterogeneous IS.</p> <p>Methods</p> <p>The literature was systematically reviewed between 1995â2005 to identify articles mentioning patient records, computers and data integration or sharing.</p> <p>Results</p> <p>Of 3124 articles, 84 were included describing 56 distinct projects. Most of the projects were on a regional scale. Integration was most commonly accomplished by messaging with pre-defined templates and middleware solutions. HL7 was the most widely used messaging standard. Direct database access and web services were the most common communication methods. The user interface for most systems was a Web browser. Regarding the type of medical data shared, 77% of projects integrated diagnosis and problems, 67% medical images and 65% lab results. More recently significantly more IS are extending to primary care and integrating referral letters.</p> <p>Conclusion</p> <p>It is clear that Information Systems are evolving to meet people's needs by implementing regional networks, allowing patient access and integration of ever more items of patient data. Many distinct technological solutions coexist to integrate patient data, using differing standards and data architectures which may difficult further interoperability.</p
Scientific rationale for Uranus and Neptune <i>in situ</i> explorations
The ice giants Uranus and Neptune are the least understood class of planets in our solar system but the most frequently observed type of exoplanets. Presumed to have a small rocky core, a deep interior comprising âŒ70% heavy elements surrounded by a more dilute outer envelope of H2 and He, Uranus and Neptune are fundamentally different from the better-explored gas giants Jupiter and Saturn. Because of the lack of dedicated exploration missions, our knowledge of the composition and atmospheric processes of these distant worlds is primarily derived from remote sensing from Earth-based observatories and space telescopes. As a result, Uranus's and Neptune's physical and atmospheric properties remain poorly constrained and their roles in the evolution of the Solar System not well understood. Exploration of an ice giant system is therefore a high-priority science objective as these systems (including the magnetosphere, satellites, rings, atmosphere, and interior) challenge our understanding of planetary formation and evolution. Here we describe the main scientific goals to be addressed by a future in situ exploration of an ice giant. An atmospheric entry probe targeting the 10-bar level, about 5 scale heights beneath the tropopause, would yield insight into two broad themes: i) the formation history of the ice giants and, in a broader extent, that of the Solar System, and ii) the processes at play in planetary atmospheres. The probe would descend under parachute to measure composition, structure, and dynamics, with data returned to Earth using a Carrier Relay Spacecraft as a relay station. In addition, possible mission concepts and partnerships are presented, and a strawman ice-giant probe payload is described. An ice-giant atmospheric probe could represent a significant ESA contribution to a future NASA ice-giant flagship mission
Fundamental Science and Engineering Questions in Planetary Cave Exploration
32 pĂĄginas.- 3 figuras.- 2 tablas.- 260 referenciasNearly half a century ago, two papers postulated the likelihood of lunar lava tube caves using mathematical models. Today, armed with an array of orbiting and fly-by satellites and survey instrumentation, we have now acquired cave data across our solar system-including the identification of potential cave entrances on the Moon, Mars, and at least nine other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we leveraged the expertise of an interdisciplinary group to identify a strategy to explore caves beyond Earth. Focusing primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration, our goal was to produce a framework to guide this subdiscipline through at least the next decade. To do this, we first assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave-principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within Martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and Martian subsurface.The following funding sources are recognized for supporting several of the contributing authors: Human Frontiers Science Program grant #RGY0066/2018 (for AAB), NASA Innovative Advanced Concepts Grant #80HQTR19C0034 (HJ, UYW, and WLW), and European Research Council, ERC Consolidator Grant #818602 (AGF), the Spanish Ministry of Science and Innovation (project PID2019-108672RJ-I00) and the "Ramon y Cajal" post-doctoral contract (grant #RYC2019-026885-I (AZM)), and Contract #80NM0018D0004 between the Jet Propulsion Laboratory, California Institute of Technology and the National Aeronautics and Space Administration (AA, MJM, KU, and LK).Peer reviewe
A roadmap for planetary caves science and exploration
2 pĂĄginas.- 1 figura.- 16 referenciasTo the Editor â 2021 is the International Year of Caves and Karst. To honour this occasion, we wish to emphasize the vast potential embodied in planetary subsurfaces. While researchers have pondered the possibility of extraterrestrial caves for more than 50 years, we have now entered the incipient phase of planetary caves exploration....Peer reviewe
The high activity of 3C 454.3 in autumn 2007: Monitoring by the WEBT during the AGILE detection
The quasar-type blazar 3C 454.3 underwent a phase of high activity in summer
and autumn 2007, which was intensively monitored in the radio-to-optical bands
by the Whole Earth Blazar Telescope (WEBT). The gamma-ray satellite AGILE
detected this source first in late July, and then in November-December 2007. In
this letter we present the multifrequency data collected by the WEBT and
collaborators during the second AGILE observing period, complemented by a few
contemporaneous data from UVOT onboard the Swift satellite. The aim is to trace
in detail the behaviour of the synchrotron emission from the blazar jet, and to
investigate the contribution from the thermal emission component. Optical data
from about twenty telescopes have been homogeneously calibrated and carefully
assembled to construct an R-band light curve containing about 1340 data points
in 42 days. This extremely well-sampled optical light curve allows us to follow
the dramatic flux variability of the source in detail. In addition, we show
radio-to-UV spectral energy distributions (SEDs) at different epochs, which
represent different brightness levels. In the considered period, the source
varied by 2.6 mag in a couple of weeks in the R band. Many episodes of fast
(i.e. intranight) variability were observed, most notably on December 12, when
a flux increase of about 1.1 mag in 1.5 hours was detected, followed by a steep
decrease of about 1.2 mag in 1 hour. The contribution by the thermal component
is difficult to assess, due to the uncertainties in the Galactic, and possibly
also intrinsic, extinction in the UV band. However, polynomial fitting of
radio-to-UV SEDs reveals an increasing spectral bending going towards fainter
states, suggesting a UV excess likely due to the thermal emission from the
accretion disc
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