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Article ; Online: Classical theory of universal quantum work distribution in chaotic and disordered non-interacting Fermi systems.

Grabarits, András / Kormos, Márton / Lovas, Izabella / Zaránd, Gergely

2022 Volume 12, Issue 1, Page(s) 15017

Abstract: We present a universal theory of quantum work statistics in generic disordered non-interacting Fermi systems, displaying a chaotic single-particle spectrum captured by random matrix theory. We consider quantum quenches both within a driven random matrix ... ...

Abstract	We present a universal theory of quantum work statistics in generic disordered non-interacting Fermi systems, displaying a chaotic single-particle spectrum captured by random matrix theory. We consider quantum quenches both within a driven random matrix formalism and in an experimentally accessible microscopic model, describing a two-dimensional disordered quantum dot. By extending Anderson's orthogonality determinant formula to compute quantum work distribution, we demonstrate that work statistics is non-Gaussian and is characterized by a few dimensionless parameters. At longer times, quantum interference effects become irrelevant and the quantum work distribution is well-described in terms of a purely classical ladder model with a symmetric exclusion process in energy space, while bosonization and mean field methods provide accurate analytical expressions for the work statistics. Our results demonstrate the universality of work distribution in generic chaotic Fermi systems, captured by the analytical predictions of a mean field theory, and can be verified by calorimetric measurements on nanoscale circuits.
Language	English
Publishing date	2022-09-02
Publishing country	England
Document type	Journal Article
ZDB-ID	2615211-3
ISSN	2045-2322 ; 2045-2322
ISSN (online)	2045-2322
ISSN	2045-2322
DOI	10.1038/s41598-022-18796-3
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: COVID-19 Pneumonia Phenotypes Detection with Electrical Impedance Tomography

Chen Rongqing / Lovas András / Benyó Balázs / Moeller Knut

Current Directions in Biomedical Engineering, Vol 8, Iss 2, Pp 707-

2022 Volume 710

Keywords	Medicine ; R
Language	English
Publishing date	2022-09-01T00:00:00Z
Publisher	De Gruyter
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Classical theory of universal quantum work distribution in chaotic and disordered non-interacting Fermi systems

András Grabarits / Márton Kormos / Izabella Lovas / Gergely Zaránd

Scientific Reports, Vol 12, Iss 1, Pp 1-

2022 Volume 12

Abstract: Abstract We present a universal theory of quantum work statistics in generic disordered non-interacting Fermi systems, displaying a chaotic single-particle spectrum captured by random matrix theory. We consider quantum quenches both within a driven ... ...

Abstract	Abstract We present a universal theory of quantum work statistics in generic disordered non-interacting Fermi systems, displaying a chaotic single-particle spectrum captured by random matrix theory. We consider quantum quenches both within a driven random matrix formalism and in an experimentally accessible microscopic model, describing a two-dimensional disordered quantum dot. By extending Anderson’s orthogonality determinant formula to compute quantum work distribution, we demonstrate that work statistics is non-Gaussian and is characterized by a few dimensionless parameters. At longer times, quantum interference effects become irrelevant and the quantum work distribution is well-described in terms of a purely classical ladder model with a symmetric exclusion process in energy space, while bosonization and mean field methods provide accurate analytical expressions for the work statistics. Our results demonstrate the universality of work distribution in generic chaotic Fermi systems, captured by the analytical predictions of a mean field theory, and can be verified by calorimetric measurements on nanoscale circuits.
Keywords	Medicine ; R ; Science ; Q
Language	English
Publishing date	2022-09-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Detection of Different COVID-19 Pneumonia Phenotypes with Estimated Alveolar Collapse and Overdistention by Bedside Electrical Impedance Tomography.

Chen, Rongqing / Lovas, András / Benyó, Balázs / Möller, Knut

IFAC-PapersOnLine

2021 Volume 54, Issue 15, Page(s) 269–274

Abstract: COVID-19 induced acute respiratory distress syndrome (ARDS) could have two different phenotypes, which was reported to have different response and outcome to the typical ARDS positive end-expiration pressure (PEEP) treatment. The identification of the ... ...

Abstract	COVID-19 induced acute respiratory distress syndrome (ARDS) could have two different phenotypes, which was reported to have different response and outcome to the typical ARDS positive end-expiration pressure (PEEP) treatment. The identification of the different phenotypes in terms of the recruitability can help improve the patient outcome. In this contribution we conducted alveolar overdistention and collapse analysis with the long term electrical impedance tomography monitoring data on two severe COVID-19 pneumonia patients. The result showed different patient reactions to the PEEP trial, revealed the progressive change in the patient status, and indicted a possible phenotype transition in one patient. It might suggest that EIT can be a practical tool to identify phenotypes and to provide progressive information of COVID-19 pneumonia.
Language	English
Publishing date	2021-11-02
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	2839185-8
ISSN	2405-8963 ; 2405-8963
ISSN (online)	2405-8963
ISSN	2405-8963
DOI	10.1016/j.ifacol.2021.10.267
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Structural priors represented by discrete cosine transform improve EIT functional imaging.

Chen, Rongqing / Krueger-Ziolek, Sabine / Lovas, András / Benyó, Balázs / Rupitsch, Stefan J / Moeller, Knut

PloS one

2023 Volume 18, Issue 5, Page(s) e0285619

Abstract: Structural prior information can improve electrical impedance tomography (EIT) reconstruction. In this contribution, we introduce a discrete cosine transformation-based (DCT-based) EIT reconstruction algorithm to demonstrate a way to incorporate the ... ...

Abstract	Structural prior information can improve electrical impedance tomography (EIT) reconstruction. In this contribution, we introduce a discrete cosine transformation-based (DCT-based) EIT reconstruction algorithm to demonstrate a way to incorporate the structural prior with the EIT reconstruction process. Structural prior information is obtained from other available imaging methods, e.g., thorax-CT. The DCT-based approach creates a functional EIT image of regional lung ventilation while preserving the introduced structural information. This leads to an easier interpretation in clinical settings while maintaining the advantages of EIT in terms of bedside monitoring during mechanical ventilation. Structural priors introduced in the DCT-based approach are of two categories in terms of different levels of information included: a contour prior only differentiates lung and non-lung region, while a detail prior includes information, such as atelectasis, within the lung area. To demonstrate the increased interpretability of the EIT image through structural prior in the DCT-based approach, the DCT-based reconstructions were compared with reconstructions from a widely applied one-step Gauss-Newton solver with background prior and from the advanced GREIT algorithm. The comparisons were conducted both on simulation data and retrospective patient data. In the simulation, we used two sets of forward models to simulate different lung conditions. A contour prior and a detail prior were derived from simulation ground truth. With these two structural priors, the reconstructions from the DCT-based approach were compared with the reconstructions from both the one-step Gauss-Newton solver and the GREIT. The difference between the reconstructions and the simulation ground truth is calculated by the ℓ2-norm image difference. In retrospective patient data analysis, datasets from six lung disease patients were included. For each patient, a detail prior was derived from the patient's CT, respectively. The detail prior was used for the reconstructions using the DCT-based approach, which was compared with the reconstructions from the GREIT. The reconstructions from the DCT-based approach are more comprehensive and interpretable in terms of preserving the structure specified by the priors, both in simulation and retrospective patient data analysis. In simulation analysis, the ℓ2-norm image difference of the DCT-based approach with a contour prior decreased on average by 34% from GREIT and 49% from the Gauss-Newton solver with background prior; for reconstructions of the DCT-based approach with detail prior, on average the ℓ2-norm image difference is 53% less than GREIT and 63% less than the reconstruction with background prior. In retrospective patient data analysis, the reconstructions from both the DCT-based approach and GREIT can indicate the current patient status, but the DCT-based approach yields more interpretable results. However, it is worth noting that the preserved structure in the DCT-based approach is derived from another imaging method, not from the EIT measurement. If the structural prior is outdated or wrong, the result might be misleadingly interpreted, which induces false clinical conclusions. Further research in terms of evaluating the validity of the structural prior and detecting the outdated prior is necessary.
MeSH term(s)	Humans ; Tomography/methods ; Retrospective Studies ; Image Processing, Computer-Assisted/methods ; Electric Impedance ; Tomography, X-Ray Computed ; Algorithms
Language	English
Publishing date	2023-05-11
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2267670-3
ISSN	1932-6203 ; 1932-6203
ISSN (online)	1932-6203
ISSN	1932-6203
DOI	10.1371/journal.pone.0285619
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Structural priors represented by discrete cosine transform improve EIT functional imaging.

Rongqing Chen / Sabine Krueger-Ziolek / András Lovas / Balázs Benyó / Stefan J Rupitsch / Knut Moeller

PLoS ONE, Vol 18, Iss 5, p e

2023 Volume 0285619

Abstract	Structural prior information can improve electrical impedance tomography (EIT) reconstruction. In this contribution, we introduce a discrete cosine transformation-based (DCT-based) EIT reconstruction algorithm to demonstrate a way to incorporate the structural prior with the EIT reconstruction process. Structural prior information is obtained from other available imaging methods, e.g., thorax-CT. The DCT-based approach creates a functional EIT image of regional lung ventilation while preserving the introduced structural information. This leads to an easier interpretation in clinical settings while maintaining the advantages of EIT in terms of bedside monitoring during mechanical ventilation. Structural priors introduced in the DCT-based approach are of two categories in terms of different levels of information included: a contour prior only differentiates lung and non-lung region, while a detail prior includes information, such as atelectasis, within the lung area. To demonstrate the increased interpretability of the EIT image through structural prior in the DCT-based approach, the DCT-based reconstructions were compared with reconstructions from a widely applied one-step Gauss-Newton solver with background prior and from the advanced GREIT algorithm. The comparisons were conducted both on simulation data and retrospective patient data. In the simulation, we used two sets of forward models to simulate different lung conditions. A contour prior and a detail prior were derived from simulation ground truth. With these two structural priors, the reconstructions from the DCT-based approach were compared with the reconstructions from both the one-step Gauss-Newton solver and the GREIT. The difference between the reconstructions and the simulation ground truth is calculated by the ℓ2-norm image difference. In retrospective patient data analysis, datasets from six lung disease patients were included. For each patient, a detail prior was derived from the patient's CT, respectively. The detail prior was used for the ...
Keywords	Medicine ; R ; Science ; Q
Subject code	518
Language	English
Publishing date	2023-01-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Electrical Impedance Tomography might be a Practical Tool to Provide Information about COVID-19 Pneumonia Progression

Chen Rongqing / Lovas András / Benyó Balázs / Moeller Knut

Current Directions in Biomedical Engineering, Vol 7, Iss 2, Pp 276-

2021 Volume 278

Abstract: COVID-19 induced acute respiratory distress syndrome (ARDS) could have two different phenotypes, which might have different response and outcome to the traditional ARDS positive end-expiration pressure (PEEP) treatment. The identification of the ... ...

Abstract	COVID-19 induced acute respiratory distress syndrome (ARDS) could have two different phenotypes, which might have different response and outcome to the traditional ARDS positive end-expiration pressure (PEEP) treatment. The identification of the different phenotypes in terms of the PEEP recruitment can help improve the patients’ outcome. In this contribution we reported a COVID-19 patient with seven-day electrical impedance tomography monitoring. From the conductivity distribution difference image analysis of the data, a clear course developing trend can be observed in addition to the phenotype identification. This case might suggest that EIT can be a practical tool to identify phenotypes and to provide progressive information of COVID-19 pneumonia.
Keywords	electrical impedance tomography ; covid-19 pneumonia ; progressive information ; monitoring ; ards ; Medicine ; R
Language	English
Publishing date	2021-10-01T00:00:00Z
Publisher	De Gruyter
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Drone-Based Gamma Radiation Dose Distribution Survey with a Discrete Measurement Point Procedure.

Molnar, Andras / Domozi, Zsolt / Lovas, Istvan

Sensors (Basel, Switzerland)

2021 Volume 21, Issue 14

Abstract: A dose distribution map can be created using geographic information system (GIS) methods from sensor data that do not provide image information in a classical way. The results of discrete radiation measurements can be properly represented in a uniform ... ...

Abstract	A dose distribution map can be created using geographic information system (GIS) methods from sensor data that do not provide image information in a classical way. The results of discrete radiation measurements can be properly represented in a uniform raster above the surface. If the radiation measured at each site does not show a jump-like change, a dose distribution map can be prepared by interpolating the measured values. The coordinates of the measuring points can be used to calibrate the map. The calibrated and georeferenced map is suitable for locating hidden or lost radiation sources or for mapping active debris scattered during a possible reactor accident. The advantage of the developed method is the measurement can be performed with a small multicopter, cost-effectively, even without human intervention. The flight time of small multicopters is very limited, so it is especially important to increase the efficiency of the measurement. During the experiments, a practical comparison of several methods was made with regard to the measurement procedure. Similarly, based on the measurement experience, the detector system was further developed and tested in three main steps. A system was developed with a detector system with a total weight of 500 g, including a battery capable of operating the detector for at least 120 min. The device is capable of detecting an average of 30 events/min at of 0.01 μSv/h background radiation. Experiments have shown that the system is able to significantly detect a source with an activity of 300 μSv/h by scanning above 10 m ground level.
MeSH term(s)	Gamma Rays ; Humans ; Radiation Monitoring
Language	English
Publishing date	2021-07-20
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2052857-7
ISSN	1424-8220 ; 1424-8220
ISSN (online)	1424-8220
ISSN	1424-8220
DOI	10.3390/s21144930
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Article: Orbital Cellulitis following COVID-19 Vaccination.

Hári-Kovács, András / Vass, Attila / Lovas, Péter / Vince, Viola / Végh, Mihály / Tóth-Molnár, Edit

Case reports in ophthalmology

2022 Volume 13, Issue 1, Page(s) 210–214

Abstract: A 72-year-old male patient was referred to our outpatient clinic with a painful left eye protrusion accompanied by marked conjunctival chemosis and external ophthalmoplegia being progressed despite topical and oral antibiotic therapy. He developed ocular ...

Abstract	A 72-year-old male patient was referred to our outpatient clinic with a painful left eye protrusion accompanied by marked conjunctival chemosis and external ophthalmoplegia being progressed despite topical and oral antibiotic therapy. He developed ocular symptoms 9 days after receiving his second SARS-CoV-2 vaccine (VeroCell). Of note, in previous history, 2 weeks after the first dose of the COVID-19 vaccine, he also developed a life-threatening laryngeal oedema treated at an emergency care unit. MRI of the orbit excluded pansinusitis as possible origin of the orbital cellulitis, and repeated COVID-19 antigen and antibody PCR tests were negative during his hospitalization. On the next day after his admittance, parenteral dexamethasone 250 mg/die treatment was commenced resulting in a quick and complete resolution of the symptoms. Due to the facts regarding this case, such as the temporal coincidence and the lack of respective comorbidity, there might be a causative relationship between the vaccination and the presented orbital cellulitis. To the best of our knowledge, this is the first report on orbital cellulitis as a possible ocular adverse event following COVID-19 vaccination.
Language	English
Publishing date	2022-03-21
Publishing country	Switzerland
Document type	Case Reports
ZDB-ID	2577666-6
ISSN	1663-2699
ISSN	1663-2699
DOI	10.1159/000523803
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Article ; Online: Long term EIT based compliance monitoring in COVID-19 patients

Isasa Reinoso Imanol / Chen Rongqing / Lovas András / Moeller Knut

Current Directions in Biomedical Engineering, Vol 7, Iss 2, Pp 323-

2021 Volume 326

Abstract: The COVID-19 is a viral infection that causes respiratory complications. Infected lungs often present ground glass opacities, thus suggesting that medical imaging technologies could provide useful information for the disease diagnosis, treatment, and ... ...

Abstract	The COVID-19 is a viral infection that causes respiratory complications. Infected lungs often present ground glass opacities, thus suggesting that medical imaging technologies could provide useful information for the disease diagnosis, treatment, and posterior recovery. The Electrical Impedance Tomography (EIT) is a non-invasive, radiationfree, and continuous technology that generates images by using a sequence of current injections and voltage measurements around the body, making it very appropriate for the study to monitor the regional behaviour of the lung. Moreover, this tool could also be used for a preliminary COVID-19 phenotype classification of the patients. This study is based on the monitoring of lung compliances of two COVID-19-infected patients: the results indicate that one of them could belong to the H-type, while the other is speculated belongs to L-type. It has been concluded that the EIT is a useful tool to obtain information regarding COVID-19 patients and could also be used to classify different phenotypes.
Keywords	electrical impedance tomography ; phenotype ; lung compliance ; covid-19 pneumonia ; Medicine ; R
Subject code	610
Language	English
Publishing date	2021-10-01T00:00:00Z
Publisher	De Gruyter
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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