loss of coherence
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2021 ◽  
pp. 1-5
Author(s):  
Servet Duran ◽  
Dietske Miedema ◽  
Bülent Ergin ◽  
Can Ince

Cytokemia is associated with microcirculatory alterations often with persistent loss of coherence between the micro- and macrocirculation, linked to organ failure and poor outcome of septic patients. Addition of a hemoadsorbant filter to an extracorporeal circuit next to conventional treatment of septic shock results in the hematological clearance of cytokines, hypothetically leading to normalization of the microcirculation and thus organ perfusion. Bedside sublingual microcirculatory assessment using handheld vital microscopy allows real-time direct visualization of the microcirculation and its response to therapy. This is demonstrated in the present case report of an 83-year-old man admitted to our intensive care unit after surgical repair of a colonic perforation for fecal soiling after a low anterior resection for a rectum carcinoma, with leakage of bowel content at the resection site. The clinical course of this patient can be described as having undergone adequate surgical treatment taking away the source of the disease, followed by optimal support including antibiotic treatment in the ICU. However, during the course of his stay in the ICU, his condition deteriorated with symptoms consistent with septic shock. Our report shows that the addition of a hemoadsorbent (CytoSorb) to the continuous renal replacement therapy circuit was associated with an improvement in the condition of our severely ill patient with abdominal sepsis. Parallel to the clinical improvement of our patient, the functional parameters of the microcirculation also showed improvement suggesting that such a noninvasive real-time evaluation of the status of the microcirculation may be a sensitive diagnostic tool to monitor the effectiveness of hemoadsorbent therapy.


2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
André de Gouvêa ◽  
Valentina De Romeri ◽  
Christoph A. Ternes

Abstract Reactor experiments are well suited to probe the possible loss of coherence of neutrino oscillations due to wave-packets separation. We combine data from the short-baseline experiments Daya Bay and the Reactor Experiment for Neutrino Oscillation (RENO) and from the long baseline reactor experiment KamLAND to obtain the best current limit on the reactor antineutrino wave-packet width, σ > 2.1 × 10−4 nm at 90% CL. We also find that the determination of standard oscillation parameters is robust, i.e., it is mostly insensitive to the presence of hypothetical decoherence effects once one combines the results of the different reactor neutrino experiments.


2021 ◽  
Vol 103 (2) ◽  
Author(s):  
Ralf Wanzenböck ◽  
Stefan Donsa ◽  
Harald Hofstätter ◽  
Othmar Koch ◽  
Peter Schlagheck ◽  
...  

Atoms ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 5
Author(s):  
Raúl O. Barrachina ◽  
Francisco Navarrete ◽  
Marcelo F. Ciappina

In the study of collision processes, a series of conditions is usually assumed. One of them is that the beam of projectiles is coherent in lengths greater than those of the targets against which it strikes. However, recent experimental results and theoretical analyzes have shown that this assumption can not only fail, but that it is possible to manipulate the coherence length experimentally to go from a coherent situation to an incoherent one. The most conspicuous and studied manifestation of such loss of coherence is the disappearance of interference effects. However, in the present work we show that a strong decrease can also occur in the magnitude of the cross section, not only differential but also total, due to an atomic concealment effect.


Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6702
Author(s):  
Jorge Jorge Ruiz ◽  
Risto Vehmas ◽  
Juha Lemmetyinen ◽  
Josu Uusitalo ◽  
Janne Lahtinen ◽  
...  

We introduce SodSAR, a fully polarimetric tower-based wide frequency (1–10 GHz) range Synthetic Aperture Radar (SAR) aimed at snow, soil and vegetation studies. The instrument is located in the Arctic Space Centre of the Finnish Meteorological Institute in Sodankylä, Finland. The system is based on a Vector Network Analyzer (VNA)-operated scatterometer mounted on a rail allowing the formation of SAR images, including interferometric pairs separated by a temporal baseline. We present the description of the radar, the applied SAR focusing technique, the radar calibration and measurement stability analysis. Measured stability of the backscattering intensity over a three-month period was observed to be better than 0.5 dB, when measuring a target with a known radar cross section. Deviations of the estimated target range were in the order of a few cm over the same period, indicating also good stability of the measured phase. Interforometric SAR (InSAR) capabilities are also discussed, and as a example, the coherence of subsequent SAR acquisitions over the observed boreal forest stand are analyzed over increasing temporal baselines. The analysis shows good conservation of coherence in particular at L-band, while higher frequencies are susceptible to loss of coherence in particular for dense vegetation. The potential of the instrument for satellite calibration and validation activities is also discussed.


2020 ◽  
Vol 12 (40) ◽  
pp. 45111-45121
Author(s):  
Xiaoping Chen ◽  
Teddy Salim ◽  
Ziyu Zhang ◽  
Xiaojiang Yu ◽  
Ira Volkova ◽  
...  

2020 ◽  
Vol 2020 (8) ◽  
Author(s):  
André de Gouvêa ◽  
Valentina De Romeri ◽  
Christoph A. Ternes

Abstract We explore how well reactor antineutrino experiments can constrain or measure the loss of quantum coherence in neutrino oscillations. We assume that decoherence effects are encoded in the size of the neutrino wave-packet, σ. We find that the current experiments Daya Bay and the Reactor Experiment for Neutrino Oscillation (RENO) already constrain σ > 1.0×10−4 nm and estimate that future data from the Jiangmen Underground Neutrino Observatory (JUNO) would be sensitive to σ < 2.1 × 10−3 nm. If the effects of loss of coherence are within the sensitivity of JUNO, we expect σ to be measured with good precision. The discovery of nontrivial decoherence effects in JUNO would indicate that our understanding of the coherence of neutrino sources is, at least, incomplete.


Entropy ◽  
2020 ◽  
Vol 22 (7) ◽  
pp. 776
Author(s):  
Craig S. Lent

Quantum computation is often limited by environmentally-induced decoherence. We examine the loss of coherence for a two-branch quantum interference device in the presence of multiple witnesses, representing an idealized environment. Interference oscillations are visible in the output as the magnetic flux through the branches is varied. Quantum double-dot witnesses are field-coupled and symmetrically attached to each branch. The global system—device and witnesses—undergoes unitary time evolution with no increase in entropy. Witness states entangle with the device state, but for these blind witnesses, which-path information is not able to be transferred to the quantum state of witnesses—they cannot “see” or make a record of which branch is traversed. The system which-path information leaves no imprint on the environment. Yet, the presence of a multiplicity of witnesses rapidly quenches quantum interference.


2020 ◽  
Vol 8 ◽  
pp. 3-14
Author(s):  
Gianfranco Minati

We briefly propose a possibly more precise systemic understanding of the process of crisis with the purpose of allowing suitable, appropriate modifying interventions. Examples and types of crises are introduced. At a suitable level of representation we consider crisis as a non-autonomous parasitic process of the hosting one(s); processes acquiring characteristics autonomous with respect to those of the hosting process(es); processes converging to degeneration and malfunctioning; which are emergent and given by coherent, subsequent and related new degenerative properties or loss of coherence among emergent processes of the hosting one(s). Possible symptoms for diagnostics and prediction of processes of crisis are outlined. Types of crisis are considered and some generic exemplifying types of actions on crises are proposed. The main purpose of this article is to show that different types of processes of crisis having different natures are possible and that suitable, appropriate approaches should be adopted.


2020 ◽  
Vol 102 (2) ◽  
pp. 759-770
Author(s):  
Dawid Dudkowski ◽  
Jerzy Wojewoda ◽  
Krzysztof Czołczyński ◽  
Tomasz Kapitaniak

AbstractIn this paper, we re-examine the dynamics of double pendulum in numerical simulations and experimental observations. Typical types of behaviors of the parametrically excited double pendula are presented, including chaos, rotations and periodic oscillations, and the bifurcation analysis is performed, exhibiting complex transitions from one type of motion into another. The character of the observed dynamics is analyzed using Lyapunov exponents, which confirms the hyperchaotic nature of the system. Particular attention is paid to the transient behaviors, showing that the length of the irregular motion can be extremely sensitive to both parameters and initial conditions. Apart from the single double pendulum, we consider also the case of two coupled double pendula, connected by a typical linear scheme. Our results show that depending on the network’s parameters, one can observe the phenomenon of a transient chaotic synchronization, during which the units spontaneously synchronize and desynchronize. The loss of coherence is strictly related to the motion of the pendula around the unstable equilibrium of the system, which has been confirmed in the scenario of pure chaotic oscillations. We determine the regions of the occurrence of transient synchronization in the coupling parameters’ plane, as well as study the statistical properties of the observed patterns. We show that the problem of determining the final dynamical attractor of the system is not straightforward.


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