10,605 research outputs found
Perforatationstrauma im Gesichtsschädel: Eine ungewöhnliche Verletzung beim Skifahren
Zusammenfassung: Pfählungsverletzungen am Kopf und im Gesicht sind selten. Wir berichten über den Fall eines 48-jährigen Patienten, der sich beim Skifahren eine Pfählungsverletzung des Gesichtschädels mit einem 11cm langen Ast zugezogen hatte. Der Patient präsentierte sich bei der Einlieferung in die Klinik neurologisch unauffällig und kreislaufstabil. In den CT-Untersuchungen des Kopfs konnten Frakturen im Gesichtschädel und ein 11cm langer Fremdkörper, ausgehend vom Sinus maxillaris durch den Gesichtschädel bis paravertebral reichend, ohne Verletzung von Gefäßen nachgewiesen werden. Zusätzlich zog sich der Patient Frakturen an der Hand und an den Rippen zu. Er wurde in ein Zentrum für Kiefer- und Gesichtschirurgie verlegt, mehrfach operiert und konnte 8Monate nach dem Unfall wieder in sein gewohntes privates und berufliches Leben zurückkehre
0.75 atoms improve the clock signal of 10,000 atoms
Since the pioneering work of Ramsey, atom interferometers are employed for
precision metrology, in particular to measure time and to realize the second.
In a classical interferometer, an ensemble of atoms is prepared in one of the
two input states, whereas the second one is left empty. In this case, the
vacuum noise restricts the precision of the interferometer to the standard
quantum limit (SQL). Here, we propose and experimentally demonstrate a novel
clock configuration that surpasses the SQL by squeezing the vacuum in the empty
input state. We create a squeezed vacuum state containing an average of 0.75
atoms to improve the clock sensitivity of 10,000 atoms by 2.05 dB. The SQL
poses a significant limitation for today's microwave fountain clocks, which
serve as the main time reference. We evaluate the major technical limitations
and challenges for devising a next generation of fountain clocks based on
atomic squeezed vacuum.Comment: 9 pages, 6 figure
Perforatationstrauma im Gesichtsschädel. Eine ungewöhnliche Verletzung beim Skifahren
Facial perforation injuries are very rare. We describe a case of a 48-year-old man who sustained a perforation trauma from an 11 cm long wooden tree branch in the middle of the face in a skiing accident. He suffered from additional injuries, such as fractures of the ribs and hand, but was neurologically without pathologic findings and was cardiopulmonary stable.The branch penetrated the head from the sinus maxillaris through the maxilla just missing the internal and external carotid arteries and ending just short of the cervical vertebra. The patient was transported to a center for oral and maxillofacial surgery and underwent several operations.He could return to his normal social and professional life 8 months after the accident
Use of Imaging Spectrometer Data and Multispectral Imagery for Improved Earthquake Response
Imaging and Applied Optics Technical Digest, 2012Multispectral imagery and imaging spectrometer data are used to develop prototype
map products for improved earthquake response. A tiered approach keyed to post-event
communications infrastructure is directed at providing critical information to emergency services personnel.This research is supported by the Science and Technology (S&T) Directorate, Department of Homeland Security (DHS). We gratefully acknowledge the participation of emergency responders and managers from the cities and counties of Monterey, Los Angeles, San Diego, and Riverside California. We also appreciate contributions during project definition stage and follow-ups by the California Emergency Management Agency (Cal EMA) and the Federal Emergency Management Agency (FEMA), the U.S. Geological Survey, and DHS. AVIRIS data were acquired by NASA/JPL. The LiDAR data were provided by the Association of Monterey Bay Area Governments, via a USGS grant through the American Reinvestment and Recovery Act of 2009. WV-2 data were provided by the National Geospatial Intelligence Agency (NGA) under the NextView imagery license agreement
Satisfying the Einstein-Podolsky-Rosen criterion with massive particles
In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of
quantum mechanics by devising a quantum state of two massive particles with
maximally correlated space and momentum coordinates. The EPR criterion
qualifies such continuous-variable entangled states, where a measurement of one
subsystem seemingly allows for a prediction of the second subsystem beyond the
Heisenberg uncertainty relation. Up to now, continuous-variable EPR
correlations have only been created with photons, while the demonstration of
such strongly correlated states with massive particles is still outstanding.
Here, we report on the creation of an EPR-correlated two-mode squeezed state in
an ultracold atomic ensemble. The state shows an EPR entanglement parameter of
0.18(3), which is 2.4 standard deviations below the threshold 1/4 of the EPR
criterion. We also present a full tomographic reconstruction of the underlying
many-particle quantum state. The state presents a resource for tests of quantum
nonlocality and a wide variety of applications in the field of
continuous-variable quantum information and metrology.Comment: 8 pages, 7 figure
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