Hybridisation of the cavity modes and the excitons to polariton states together with the coupling to the vibrational modes determine the linear optical properties of organic semiconductors in microcavities. In this article we compute the refractive index for such system using the Holstein-Tavis-Cummings model and determine then the linear optical properties using the transfer matrix method. We first extract the parameters for the exciton in our model from fitting to experimentally measured absorption of a 2,7-bis[9,9-di(4-methylphenyl)-fluoren-2-yl]-9,9-di(4-methylphenyl) fluorene (TDAF) molecular thin film.
View Article and Find Full Text PDFCarbonaceous aerosols (CA), composed of black carbon (BC) and organic matter (OM), significantly impact the climate. Light absorption properties of CA, particularly of BC and brown carbon (BrC), are crucial due to their contribution to global and regional warming. We present the absorption properties of BC (b) and BrC (b) inferred using Aethalometer data from 44 European sites covering different environments (traffic (TR), urban (UB), suburban (SUB), regional background (RB) and mountain (M)).
View Article and Find Full Text PDFModifying the energy landscape of existing molecular emitters is an attractive challenge with favourable outcomes in chemistry and organic optoelectronic research. It has recently been explored through strong light-matter coupling studies where the organic emitters were placed in an optical cavity. Nonetheless, a debate revolves around whether the observed change in the material properties represents novel coupled system dynamics or the unmasking of pre-existing material properties induced by light-matter interactions.
View Article and Find Full Text PDFBackground: Decrease in signal intensity (SI) of the nucleus pulposus (NP) on T2-weighted (T2W) images, a sign of disc degeneration (DD), is usually graded based on an observer's image interpretation. No gold standard for quantitative assessment of NP SI exists to date.
Purpose: To compare different quantitative methods and visual gradings of lumbar DD and to evaluate the ability of the quantitative methods to differentiate DD grades.
In this Letter we investigate the concept of quantum work and its measurability from the viewpoint of quantum measurement theory. Very often, quantum work and fluctuation theorems are discussed in the framework of projective two-point measurement (TPM) schemes. According to a well-known no-go theorem, there is no work observable which satisfies both (i) an average work condition and (ii) the TPM statistics for diagonal input states.
View Article and Find Full Text PDFWe investigate a composite quantum collision model with measurements on the memory part, which effectively probe the system. The framework allows us to adjust the measurement strength, thereby tuning the dynamical map of the system. For a two-qubit setup with a symmetric and informationally complete measurement on the memory, we study the divisibility of the resulting dynamics in dependence of the measurement strength.
View Article and Find Full Text PDFWe study non-Markovian dynamics of an open quantum system system interacting with a nonstationary squeezed bosonic reservoir. We derive exact and approximate descriptions for the open system dynamics. Focusing on the spin boson model, we compare exact dynamics with Redfield theory and a quantum optical master equation for both short and long time dynamics and in non-Markovian and Markov regimes.
View Article and Find Full Text PDFBackground: The novel coronavirus-associated ARDS (COVID-19 ARDS) often requires invasive mechanical ventilation. A spectrum of atypical ARDS with different phenotypes (high vs low static compliance) has been hypothesized in COVID-19.
Methods: We conducted a retrospective analysis to identify respiratory mechanics in COVID-19 ARDS.
The coherence of an individual quantum state can be meaningfully discussed only when referring to a preferred basis. This arbitrariness can, however, be lifted when considering sets of quantum states. Here we introduce the concept of set coherence for characterizing the coherence of a set of quantum systems in a basis-independent way.
View Article and Find Full Text PDFIntroduction: An increase in brain white matter hyperintensities (WMHs) and a decrease in white matter fractional anisotrophy (FA) have been detected in bipolar I (BPI), II (BPII), and major depressive disorder (MDD) patients. Their relationship, and differences in diagnostic groups are obscure. Longitudinal studies are rare.
View Article and Find Full Text PDFUnlabelled: To explore demographics, comorbidities, transfers, and mortality in critically ill patients with confirmed severe acute respiratory syndrome coronavirus 2.
Design: Retrospective cohort study.
Setting: Data were collected from a large tertiary care public hospital ICU that is part of the largest public healthcare network in the United States.
Study Design: A prospective follow-up study.
Objective: The aim of this study was to investigate whether early lumbar disc degeneration (DD) in young low back pain (LBP) patients predicts progression of degenerative changes, pain, or disability in a 30-year follow-up.
Summary Of Background Data: MRI is an accurate method for studying degenerative changes in intervertebral discs.
Objectives: This study investigated associations between patient and injury characteristics and false-negative (FN) focused assessment with sonography for trauma (FAST) in pediatric blunt abdominal trauma (BAT). We also evaluated the effects of FN FAST on in-hospital mortality and length of stay (LOS) variables.
Methods: This retrospective cohort studied children younger than 18 years between January 1, 2002, and December 31, 2013, with BAT, documented FAST, and pathologic fluid on computed tomography, surgery, or autopsy.
Urbanisation and industrialisation led to the increase of ambient particulate matter (PM) concentration. While subsequent regulations may have resulted in the decrease of some PM matrices, the simultaneous changes in climate affecting local meteorological conditions could also have played a role. To gain an insight into this complex matter, this study investigated the long-term trends of two important matrices, the particle mass (PM) and particle number concentrations (PNC), and the factors that influenced the trends.
View Article and Find Full Text PDFWe address the question of verifying the quantumness of thermal machines. A Szilárd engine is truly quantum if its work output cannot be described by a local hidden state model, i.e.
View Article and Find Full Text PDFMissing data has been a challenge in air quality measurement. In this study, we develop an input-adaptive proxy, which selects input variables of other air quality variables based on their correlation coefficients with the output variable. The proxy uses ordinary least squares regression model with robust optimization and limits the input variables to a maximum of three to avoid overfitting.
View Article and Find Full Text PDFCan mitigating only particle mass, as the existing air quality measures do, ultimately lead to reduction in ultrafine particles (UFP)? The aim of this study was to provide a broader urban perspective on the relationship between UFP, measured in terms of particle number concentration (PNC) and PM (mass concentration of particles with aerodynamic diameter < 2.5 μm) and factors that influence their concentrations. Hourly average PNC and PM were acquired from 10 cities located in North America, Europe, Asia, and Australia over a 12-month period.
View Article and Find Full Text PDFWe derive a family of Gaussian non-Markovian stochastic Schrödinger equations for the dynamics of open quantum systems. The different unravelings correspond to different choices of squeezed coherent states, reflecting different measurement schemes on the environment. Consequently, we are able to give a single shot measurement interpretation for the stochastic states and microscopic expressions for the noise correlations of the Gaussian process.
View Article and Find Full Text PDFPurpose: To clarify the significance of Modic changes, bony endplate lesions, and disc degeneration as predictors of chronic low back pain (LBP) during 1-year follow-up.
Methods: 49 patients with severe, non-specific, chronic LBP, and Modic 1 lesion (M1) were prospectively studied with MRI and questionnaire. Changes in grade of disc degeneration, severity of Modic changes, Schmorl lesions, and bony endplate irregularities were evaluated and changes assessed in LBP intensity on numeric rating scale 0-10 and severity with Oswestry disability index 0-100 (ODI).
Classification to severe diseases, sciatic symptoms or non-specific back pain is recommended. Radiography in acute or subacute non-specific back pain is not recommended in the primary health care. In specialized care magnetic resonance imaging is the main imaging modality.
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