1,091 research outputs found
Mazedonienimaginationen in der deutschsprachigen Literatur seit dem 19. Jahrhundert
GegenwĂ€rtig ist Mazedonien â insbesondere aufgrund des sogenannten »Namensstreits« mit Griechenland â wieder verstĂ€rkt im deutschsprachigen Mediendiskurs prĂ€sent. Worum aber handelt es sich, wenn von Mazedonien die Rede ist? Die mediale ReprĂ€sentation der Region bleibt oft diffus und ist stark von Stereotypen geprĂ€gt. Benjamin Langer zeigt in seiner umfassenden Analyse erstmals auf, wie diese sĂŒdosteuropĂ€ische Region in deutschsprachigen Texten aus einer terra incognita an der Peripherie Europas geformt und mit Zuschreibungen versehen wurde. In zehn thematischen Kapiteln weist er nach, wie wirkmĂ€chtig diese Bilder trotz ihrer WidersprĂŒchlichkeit und wechselnden Instrumentalisierung bis heute sind
Managing diabetes with nanomedicine: challenges and opportunities
Nanotechnology-based approaches hold substantial potential for improving the care of patients with diabetes. Nanoparticles are being developed as imaging contrast agents to assist in the early diagnosis of type 1 diabetes. Glucose nanosensors are being incorporated in implantable devices that enable more accurate and patient-friendly real-time tracking of blood glucose levels, and are also providing the basis for glucose-responsive nanoparticles that better mimic the body's physiological needs for insulin. Finally, nanotechnology is being used in non-invasive approaches to insulin delivery and to engineer more effective vaccine, cell and gene therapies for type 1 diabetes. Here, we analyse the current state of these approaches and discuss key issues for their translation to clinical practice.Leona M. and Harry B. Helmsley Charitable Trust (Grant 09PG-T1D027)Juvenile Diabetes Research Foundation International (17-2007-1063)Juvenile Diabetes Research Foundation International (3-2013-178)Juvenile Diabetes Research Foundation International (3-2011-310)United States. National Institutes of Health (EB000244)United States. National Institutes of Health (EB000351)United States. National Institutes of Health (DE013023)United States. National Institutes of Health (CA151884
A Quantitative Graph-Based Approach to Monitoring Ice-Wedge Trough Dynamics in Polygonal Permafrost Landscapes
In response to increasing Arctic temperatures, ice-rich permafrost landscapes are undergoing rapid changes. In permafrost lowlands, polygonal ice wedges are especially prone to degradation. Melting of ice wedges results in deepening troughs and the transition from low-centered to high-centered ice-wedge polygons. This process has important implications for surface hydrology, as the connectivity of such troughs determines the rate of drainage for these lowland landscapes. In this study, we present a comprehensive, modular, and highly automated workflow to extract, to represent, and to analyze remotely sensed ice-wedge polygonal trough networks as a graph (i.e., network structure). With computer vision methods, we efficiently extract the trough locations as well as their geomorphometric information on trough depth and width from high-resolution digital elevation models and link these data within the graph. Further, we present and discuss the benefits of graph analysis algorithms for characterizing the erosional development of such thaw-affected landscapes. Based on our graph analysis, we show how thaw subsidence has progressed between 2009 and 2019 following burning at the Anaktuvuk River fire scar in northern Alaska, USA. We observed a considerable increase in the number of discernible troughs within the study area, while simultaneously the number of disconnected networks decreased from 54 small networks in 2009 to only six considerably larger disconnected networks in 2019. On average, the width of the troughs has increased by 13.86%, while the average depth has slightly decreased by 10.31%. Overall, our new automated approach allows for monitoring ice-wedge dynamics in unprecedented spatial detail, while simultaneously reducing the data to quantifiable geometric measures and spatial relationships.BMBF PermaRiskNational Science FoundationPeer Reviewe
Decoding EEG brain activity for multi-modal natural language processing
Until recently, human behavioral data from reading has mainly been of
interest to researchers to understand human cognition. However, these human
language processing signals can also be beneficial in machine learning-based
natural language processing tasks. Using EEG brain activity to this purpose is
largely unexplored as of yet. In this paper, we present the first large-scale
study of systematically analyzing the potential of EEG brain activity data for
improving natural language processing tasks, with a special focus on which
features of the signal are most beneficial. We present a multi-modal machine
learning architecture that learns jointly from textual input as well as from
EEG features. We find that filtering the EEG signals into frequency bands is
more beneficial than using the broadband signal. Moreover, for a range of word
embedding types, EEG data improves binary and ternary sentiment classification
and outperforms multiple baselines. For more complex tasks such as relation
detection, further research is needed. Finally, EEG data shows to be
particularly promising when limited training data is available
From Images to Hydrologic Networks - Understanding the Arctic Landscape with Graphs
Remote sensing-based Earth Observation plays an important role in assessing environmental changes throughout our planet. As an
image-heavy domain, the evaluation of the data strongly focuses on statistical and pixel-based spatial analysis methods. However,
considering the complexity of our Earth system, there are some environmental structures and dependencies that are not possible
to accurately describe with these traditional image analysis approaches.
One example for such a limitation is the representation of (spatial) networks and their characteristics. In this study, we thus propose a computer vision approach that enables the representation of semantic information gained from images as graphs. As an example, we investigate digital terrain models of Arctic permafrost landscapes with its very characteristic polygonal patterned ground. These regular patterns, which are clearly visible in high-resolution image and elevation data, are formed by subsurface ice bodies that are very vulnerable to rising temperatures in a warming Arctic. Observing these networksâ topologies and metrics in space and time with graph analysis thus allows insights into the landscapeâs complex geomorphology, hydrology, and ecology and therefore helps to quantify how they interact with climate change. We show that results extracted with this analytical and highly automated approach are in line with those gathered from other manual studies or from manual validation. Thus, with this approach, we introduce a method that, for the first time, enables upscaling of such terrain and network analysis to potentially pan-Arctic scales where collecting in-situ field data is strongly limited
Palliative thoracic radiotherapy in lung cancer: An American Society for Radiation Oncology evidence-based clinical practice guideline
AbstractPurposeTo provide guidance to physicians and patients with regard to the use of external beam radiotherapy, endobronchial brachytherapy, and concurrent chemotherapy in the setting of palliative thoracic treatment for lung cancer, based on available evidence complemented by expert opinion.Methods and MaterialsA Task Force authorized by the American Society for Radiation Oncology (ASTRO) Board of Directors synthesized and assessed evidence from 3 systematic reviews on the following topics: (1) dose fractionation in thoracic external beam radiotherapy (EBRT); (2) clinical utility of initial and salvage endobronchial brachytherapy (EBB); and (3)Â use of concurrent chemotherapy (CC) with palliative thoracic radiotherapy. Practice guideline recommendations were produced and are contained herein.ResultsStudies suggest that higher dose/fractionation palliative EBRT regimens (eg, 30 Gy/10 fraction equivalent or greater) are associated with modest improvements in survival and total symptom score, particularly in patients with good performance status. As these improvements are associated with an increase in esophageal toxicity, various shorter EBRT dose/fractionation schedules (eg, 20 Gy in 5 fractions, 17 Gy in 2 weekly fractions, 10 Gy in 1 fraction), which provide good symptomatic relief with fewer side effects, can be used for patients requesting a shorter treatment course and/or in those with a poor performance status. No defined role for EBB in the routine initial palliative treatment of chest disease has been demonstrated; however, EBB can be a reasonable option for the palliation of endobronchial lesions causing obstructive symptomatology including lung collapse, or for hemoptysis after EBRT failure. The integration of concurrent chemotherapy with palliative intent/fractionated radiotherapy is not currently supported by the medical literature.ConclusionThis Guideline is intended to serve as a guide for the use of EBRT, EBB, and CC in thoracic palliation of lung cancer outside the clinical trial setting. Further prospective clinical investigations with relevant palliative endpoints into the respective roles of EBB and CC/targeted therapy in the thoracic palliation of lung cancer are warranted, given the current state of the medical literature in these areas
Statistical Mechanics of Nonuniform Magnetization Reversal
The magnetization reversal rate via thermal creation of soliton pairs in
quasi-1D ferromagnetic systems is calculated. Such a model describes e.g. the
time dependent coercivity of elongated particles as used in magnetic recording
media. The energy barrier that has to be overcome by thermal fluctuations
corresponds to a soliton-antisoliton pair whose size depends on the external
field. In contrast to other models of first order phase transitions such as the
phi^4 model, an analytical expression for this energy barrier is found for all
values of the external field. The magnetization reversal rate is calculated
using a functional Fokker-Planck description of the stochastic magnetization
dynamics. Analytical results are obtained in the limits of small fields and
fields close to the anisotropy field. In the former case the hard-axis
anisotropy becomes effectively strong and the magnetization reversal rate is
shown to reduce to the nucleation rate of soliton-antisoliton pairs in the
overdamped double sine-Gordon model. The present theory therefore includes the
nucleation rate of soliton-antisoliton pairs in the double sine-Gordon chain as
a special case. These results demonstrate that for elongated particles, the
experimentally observed coercivity is significantly lower than the value
predicted by the standard theories of N\'eel and Brown.Comment: 21 pages RevTex 3.0 (twocolumn), 6 figures available on request, to
appear in Phys Rev B, Dec (1994
The Dosimetric Outcome of a Rotational Planning Target Volume in Patients With Oropharyngeal Cancers
An isotropic expanded Planning Target Volume (PTV) neglects patient's off-axis rotation. This study designs a rotational PTV that is used instead of the standard 3-mm Clinical Target Volume (CTV) expanded PTV in oropharyngeal cancers with the goal to reduce pharyngeal constrictor muscle (PCM) mean dose. 10 patients were retrospectively evaluated. For off-axis rotation, the image was rotated around the longitudinal axis (cervical spinal canal)â±â5 degrees. These new CTVs were combined to form the rotational PTV. The standard and rotational treatment plans were designed with the goal to keep the superior and middle PCM-CTV70 mean dose to less than 50 Gy. There were a 355 cGy reduction in the superior PCM mean dose (form 5332 to 4977 cGy) and a 506 cGy reduction in middle PCM mean dose (from 4185 to 3679 cGy). 60% of patients may have at least a 20% reduction in dysphagia probability based on a Normal Tissue Complication Probability (NTCP) formula. The superior and middle PCM mean dose were reduced to less than 50 Gy in 40 and 20% of cases. There was an association between superior PCM mean dose and overlap volume of PTV70 and superior PCM in both standard (râ=â0.92, pâ=â0.001) and rotational (râ=â0.84, pâ=â0.002) plans. This association was present for middle PCM and PTV70 (râ=â0.52, pâ=â0.02 and râ=â0.62, pâ=â0.006). Rotational PTV can lower the mean dose to superior and middle PCMs, ultimately leading to lower dysphagia rates
Governance of Digital Health Data on Cooperatively Organized Platforms â a Design Thinking Approach
More and more stakeholders are collecting data for improving their services: from scientific research over public administration to commercial enterprises. Existing data management services offer few rights of co-determination for their users. Data cooperatives aim to provide a democratic alternative to this. Through such a platform cooperative members are supposed to be enabled to share their data in a self-determined way. In this paper, we present a design thinking-based user research with stakeholders of data cooperatives in a health-data context. We provide an overview of motivations, expectations, and interfaces between a cooperative and individuals as cooperative members, organizations, representatives from research, and policy makers. In an iterative process, 34 interviews were conducted with different stakeholder groups, from which 7 personas were subsequently derived. For these, 4 prototypes were developed and tested with potential users. Our results show that all interviewed groups were very interested in the concept of data cooperatives. At the same time, it proves challenging to reconcile the conflicting internal and external requirements and to implement attractive value propositions for all stakeholders
Observational Constraints on Red and Blue Helium Burning Sequences
We derive the optical luminosity, colors, and ratios of the blue and red
helium burning (HeB) stellar populations from archival Hubble Space Telescope
observations of nineteen starburst dwarf galaxies and compare them with
theoretical isochrones from Padova stellar evolution models across
metallicities from Z=0.001 to 0.009. We find that the observational data and
the theoretical isochrones for both blue and red HeB populations overlap in
optical luminosities and colors and the observed and predicted blue to red HeB
ratios agree for stars older than 50 Myr over the time bins studied. These
findings confirm the usefulness of applying isochrones to interpret
observations of HeB populations. However, there are significant differences,
especially for the red HeB population. Specifically we find: (1) offsets in
color between the observations and theoretical isochrones of order 0.15 mag
(0.5 mag) for the blue (red) HeB populations brighter than M_V ~ -4 mag, which
cannot be solely due to differential extinction; (2) blue HeB stars fainter
than M_V ~ -3 mag are bluer than predicted; (3) the slope of the red HeB
sequence is shallower than predicted by a factor of ~3; and (4) the models
overpredict the ratio of the most luminous blue to red HeB stars corresponding
to ages <50 Myr. Additionally, we find that for the more metal-rich galaxies in
our sample (Z> 0.5 Zsolar) the red HeB stars overlap with the red giant branch
stars in the color magnitude diagrams, thus reducing their usefulness as
indicators of star formation for ages >100 Myr.Comment: 18 pages, 11 figures, 3 table
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