Nano Positioning of Single Atoms in a Micro Cavity

The coupling of individual atoms to a high-finesse optical cavity is precisely controlled and adjusted using a standing-wave dipole-force trap, a challenge for strong atom-cavity coupling. Ultracold Rubidium atoms are first loaded into potential minima of the dipole trap in the center of the cavity. Then we use the trap as a conveyor belt that we set into motion perpendicular to the cavity axis. This allows us to repetitively move atoms out of and back into the cavity mode with a repositioning precision of 135 nm. This makes possible to either selectively address one atom of a string of atoms by the cavity, or to simultaneously couple two precisely separated atoms to a higher mode of the cavity.Comment: 4 pages 5 figure

Entanglement of distant atoms by projective measurement: The role of detection efficiency

We assess proposals for entangling two distant atoms by measurement of emitted photons, analyzing how their performance depends on the photon detection efficiency. We consider schemes based on measurement of one or two photons and compare them in terms of the probability to obtain the detection event and of the conditional fidelity with which the desired entangled state is created. Based on an unravelling of the master equation, we quantify the parameter regimes in which one or the other scheme is more efficient, including the possible combination of the one-photon scheme with state purification. In general, protocols based on one-photon detection are more efficient in set-ups characterized by low photon detection efficiency, while at larger values two-photon protocols are preferable. We give numerical examples based on current experiments.Comment: 12 pages, 6 figure

A fatal case of spinal tuberculosis mistaken for metastatic lung cancer: recalling ancient Pott's disease

<p>Abstract</p> <p>Background</p> <p>Tuberculous spondylitis (Pott's disease) is an ancient human disease. Because it is rare in high-income, tuberculosis (TB) low incidence countries, misdiagnoses occur as sufficient clinical experience is lacking.</p> <p>Case presentation</p> <p>We describe a fatal case of a patient with spinal TB, who was mistakenly irradiated for suspected metastatic lung cancer of the spine in the presence of a solitary pulmonary nodule of the left upper lobe. Subsequently, the patient progressed to central nervous system TB, and finally, disseminated TB before the accurate diagnosis was established. Isolation and antimycobacterial chemotherapy were initiated after an in-hospital course of approximately three months including numerous health care related contacts and procedures.</p> <p>Conclusion</p> <p>The rapid diagnosis of spinal TB demands a high index of suspicion and expertise regarding the appropriate diagnostic procedures. Due to the devastating consequences of a missed diagnosis, Mycobacterium tuberculosis should be considered early in every case of spondylitis, intraspinal or paravertebral abscess. The presence of certain alarm signals like a prolonged history of progressive back pain, constitutional symptoms or pulmonary nodules on a chest radiograph, particularly in the upper lobes, may guide the clinical suspicion.</p

No evidence for WU polyomavirus infection in chronic obstructive pulmonary disease

Human polyomaviruses are known to cause persistent or latent infections, which are reactivated under immunosuppression. Polyomaviruses have been found to immortalize cell lines and to possess oncogenic properties. Moreover, the recently discovered Merkel cell polyomavirus shows a strong association with human Merkel cell carcinomas. Another novel human polyomavirus, WU polyomavirus (WUPyV), has been identified in respiratory specimens from patients with acute respiratory tract infections (ARTI). WUPyV has been proposed to be a pathogen in ARTI in early life and immunocompromised individuals, but so far its role as a causative agent of respiratory disease remains controversial

Early markers of atrial fibrillation recurrence after pulmonary vein isolation

Background: Postprocedural atrial extrasystole (AES) frequency predicts atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) in patients with paroxysmal AF. However, the predictive value of preprocedural AES frequency is unknown. We investigate whether preprocedural AES frequency is a feasible marker to predict (timing of) AF recurrence after PVI. Methods: Patients (N = 684) with paroxysmal or persistent AF undergoing first-time PVI were evaluated for (a) the frequency of AES/day on Holter recordings without AF prior to PVI, (b) AF episodes during the 90 days blanking period, and (c) AF recurrences afterward. The correlation between AES/day and both development and timing of AF recurrences was tested. Results: Preprocedural AES/day was similar in patients with paroxysmal (66 [20-295] AES/day) and persistent AF (115 [12-248] AES/day, P =.915). During the blanking period, 302 (44.2%) patients showed AF episodes. AF recurred in 379 (55.4%) patients at 203 (105-400) days after PVI. AF recurred more frequently in patients with persistent (N = 104 [69.3%]) than in patients with paroxysmal AF (N = 275 [51.5%], P <.001). Frequency of AES prior to PVI was not correlated with development (P =.203) or timing (P =.478) of AF recurrences. AF recurrences occurred both more frequently (P <.001) and earlier (P <.000) in patients with AF during the blanking period. Conclusion: AES/day prior to PVI is not correlated with (timing of) AF during the blanking period or AF recurrences, and is therefore not a feasible marker for AF recurrences in patients with PAF. AF during the blanking period is correlated with AF recurrence

The Impact of Latency on Perceptual Judgments and Motor Performance in Closed-loop Interaction in Virtual Reality

Waltemate T, Senna I, Hülsmann F, et al. The Impact of Latency on Perceptual Judgments and Motor Performance in Closed-loop Interaction in Virtual Reality. In: Proceedings of ACM Symposium on Virtual Reality Software and Technology. New York: ACM; 2016: 27-35