1,398 research outputs found
Broad levels in O and their relevance for the astrophysical s-process
Levels in O affect the astrophysical s-process in two opposite ways.
The neutron production is enhanced by resonances in the
C(,)O reaction at excitation energies around 7 MeV in
O, and the number of available neutrons is reduced by low-lying
resonances in the O(,)O reaction corresponding to
levels in O with excitation energies of MeV. The present work uses
the F(,)O reaction to determine absolute widths of the
relevant levels in O. The results improve the uncertainties of the
previously adopted values and resolve a discrepancy between recent studies for
the level close to the threshold of the C(,)O
reaction. In addition, improved excitation energies and widths are provided for
several states in O up to excitation energies close to 8 MeV.Comment: 5 pages, 2 figures, Phys. Rev. C (in press
Guided sparse camera pose estimation
In this paper, we present an idea for a sparse approach to calculate camera poses from RGB images
and laser distance measurements to perform subsequent facade reconstruction. The core idea is
to guide the image recording process by choosing distinctive features with the laser range finder,
e.g. building or window corners. From these distinctive features, we can establish correspondences
between views to compute metrically accurate camera poses from just a few precise measurements. In
our experiments, we achieve reasonable results in building facade reconstruction with only a fraction
of features compared to standard structure from motion
Inverse relationship between tumor proliferation markers and connexin expression in a malignant cardiac tumor originating from mesenchymal stem cell engineered tissue in a rat in vivo model
Recently, we demonstrated the beneficial effects of engineered heart tissues for the treatment of dilated cardiomyopathy in rats. For further development of this technique we started to produce engineered tissue (ET) from mesenchymal stem cells. Interestingly, we observed a malignant tumor invading the heart with an inverse relationship between proliferation markers and connexin expression
Time resolved X-ray Dark-Field Tomography Revealing Water Transport in a Fresh Cement Sample
Grating-based X-ray dark-field tomography is a promising technique for biomedical and materials research. Even if the resolution of conventional X-ray tomography does not suffice to resolve relevant structures, the dark-field signal provides valuable information about the sub-pixel microstructural properties of the sample. Here, we report on the potential of X-ray dark-field imaging to be used for time-resolved three-dimensional studies. By repeating consecutive tomography scans on a fresh cement sample, we were able to study the hardening dynamics of the cement paste in three dimensions over time. The hardening of the cement was accompanied by a strong decrease in the dark-field signal pointing to microstructural changes within the cement paste. Furthermore our results hint at the transport of water from certain limestone grains, which were embedded in the sample, to the cement paste during the process of hardening. This is indicated by an increasing scattering signal which was observed for two of the six tested limestone grains. Electron microscopy images revealed a distinct porous structure only for those two grains which supports the following interpretation of our results. When the water filled pores of the limestone grains empty during the experiment the scattering signal of the grains increases
Staged Concept for Treatment of Severe Postsaphenectomy Wound Infection
The saphenous vein remains the most commonly used conduit in coronary artery bypass surgery. Vein harvest is a critical component with significant morbidity associated with leg wounds from open technique. Occurring complications are hematoma, postoperative pain, skin changes, neuropathy, and septic or nonseptic wound complications. Within the context of a recent case, we present our approach to postsaphenectomy wound management
Constraints on Cosmological Parameters from Future Galaxy Cluster Surveys
We study the expected redshift evolution of galaxy cluster abundance between
0 < z < 3 in different cosmologies, including the effects of the cosmic
equation of state parameter w=p/rho. Using the halo mass function obtained in
recent large scale numerical simulations, we model the expected cluster yields
in a 12 deg^2 Sunyaev-Zeldovich Effect (SZE) survey and a deep 10^4 deg^2 X-ray
survey over a wide range of cosmological parameters. We quantify the
statistical differences among cosmologies using both the total number and
redshift distribution of clusters. Provided that the local cluster abundance is
known to a few percent accuracy, we find only mild degeneracies between w and
either Omega_m or h. As a result, both surveys will provide improved
constraints on Omega_m and w. The Omega_m-w degeneracy from both surveys is
complementary to those found either in studies of CMB anisotropies or of
high-redshift Supernovae (SNe). As a result, combining these surveys together
with either CMB or SNe studies can reduce the statistical uncertainty on both w
and Omega_m to levels below what could be obtained by combining only the latter
two data sets. Our results indicate a formal statistical uncertainty of about
3% (68% confidence) on both Omega_m and w when the SZE survey is combined with
either the CMB or SN data; the large number of clusters in the X-ray survey
further suppresses the degeneracy between w and both Omega_m and h. Systematics
and internal evolution of cluster structure at the present pose uncertainties
above these levels. We briefly discuss and quantify the relevant systematic
errors. By focusing on clusters with measured temperatures in the X-ray survey,
we reduce our sensitivity to systematics such as non-standard evolution of
internal cluster structure.Comment: ApJ, revised version. Expanded discussion of systematics;
Press-Schechter mass function replaced by fit from simulation
Information technology in management personnel on the example of KC "Jobs"
Analysis of the workings and personnel decisions in the field of human resource management. They are inextricably linked to the processes of information processing. The higher the effect of the use of personnel information, the more objective decisions will be made by the heads of a wide variety of human resources issues. In this regard, there is a need in the compilation and dissemination of the experience gained in the application of modern technologies, as well the creation of new software products. Consideration of "human process management" module. It is designed to automate the management processes in terms of the conduct of personnel information in the context of positions and employees in order to provide the head of information for management decision making and carrying out related activities. Consideration of the positive and negative sides of the module, as its distinctivefeatures
Surgical Therapy of Atrial Fibrillation
Atrial fibrillation (AF) can be found in an increasing number of cardiac surgical patients due to a higher patient's age and comorbidities. Atrial fibrillation is known, however, to be a risk factor for a greater mortality, and one aim of intraoperative AF treatment is to approximate early and long-term survival of AF patients to survival of patients with preoperative sinus rhythm. Today, surgeons are more and more able to perform less complex, that is, minimally invasive cardiac surgical procedures. The evolution of alternative ablation technologies using different energy sources has revolutionized the surgical therapy of atrial fibrillation and allows adding the ablation therapy without adding significant risk. Thus, the surgical treatment of atrial fibrillation in combination with the cardiac surgery procedure allows to improve the postoperative long-term survival and to reduce permanent anticoagulation in these patients. This paper focuses on the variety of incisions, lesion sets, and surgical techniques, as well as energy modalities and results of AF ablation and also summarizes future trends and current devices in use
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