58 research outputs found
Reflective Ghost Imaging through Turbulence
Recent work has indicated that ghost imaging may have applications in
standoff sensing. However, most theoretical work has addressed
transmission-based ghost imaging. To be a viable remote-sensing system, the
ghost imager needs to image rough-surfaced targets in reflection through long,
turbulent optical paths. We develop, within a Gaussian-state framework,
expressions for the spatial resolution, image contrast, and signal-to-noise
ratio of such a system. We consider rough-surfaced targets that create fully
developed speckle in their returns, and Kolmogorov-spectrum turbulence that is
uniformly distributed along all propagation paths. We address both classical
and nonclassical optical sources, as well as a computational ghost imager.Comment: 13 pages, 3 figure
Minimal-invasive anterior approach to the hip provides a better surgery-related and early postoperative functional outcome than conventional lateral approach after hip hemiarthroplasty following femoral neck fractures
Introduction Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly
require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases.
Material and methods In the present retrospective study geriatric patients with FNF (n=100) treated either by anterior
minimal-invasive surgery (AMIS; n=50) or lateral conventional surgery (LCS; n=50) were characterized (age at the time
of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative
parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration
of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and
12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed.
Results Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and
complication rates did not difer between the two groups. Further, more patients in the AMIS group achieved full weightbearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients
in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before
the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often
than patients of the LCS group. No signifcant diferences in functional and surgery-related performance could be observed
between AMIS and LCS group at 12 months postoperatively.
Conclusions In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in
the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in
these vulnerable patients
Codivergence of Mycoviruses with Their Hosts
BACKGROUND: The associations between pathogens and their hosts are complex and can result from any combination of evolutionary events such as codivergence, switching, and duplication of the pathogen. Mycoviruses are RNA viruses which infect fungi and for which natural vectors are so far unknown. Thus, lateral transfer might be improbable and codivergence their dominant mode of evolution. Accordingly, mycoviruses are a suitable target for statistical tests of virus-host codivergence, but inference of mycovirus phylogenies might be difficult because of low sequence similarity even within families. METHODOLOGY: We analyzed here the evolutionary dynamics of all mycovirus families by comparing virus and host phylogenies. Additionally, we assessed the sensitivity of the co-phylogenetic tests to the settings for inferring virus trees from their genome sequences and approximate, taxonomy-based host trees. CONCLUSIONS: While sequence alignment filtering modes affected branch support, the overall results of the co-phylogenetic tests were significantly influenced only by the number of viruses sampled per family. The trees of the two largest families, Partitiviridae and Totiviridae, were significantly more similar to those of their hosts than expected by chance, and most individual host-virus links had a significant positive impact on the global fit, indicating that codivergence is the dominant mode of virus diversification. However, in this regard mycoviruses did not differ from closely related viruses sampled from non-fungus hosts. The remaining virus families were either dominated by other evolutionary modes or lacked an apparent overall pattern. As this negative result might be caused by insufficient taxon sampling, the most parsimonious hypothesis still is that host-parasite evolution is basically the same in all mycovirus families. This is the first study of mycovirus-host codivergence, and the results shed light not only on how mycovirus biology affects their co-phylogenetic relationships, but also on their presumable host range itself
The concept of homology in phylogenetic research — its meaning and possible applications
Die einzeitige operative Behandlung einer Osteitis pubis bei vesicosymphysärer Fistel mit Anlage eines supraacetabulären Fixateur externe ist ein sicheres Verfahren zur Vermeidung operations- und infektassoziierter Komplikationen
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