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In this paper, a coupled oscillator model is employed to describe the eigen-frequencies of the coupled plasmons, which are dominated by the coupled coefficient and the frequency offset defined by us. From this, we present a novel physical model to describe the influence of the Coulomb potential and the electrostatic potential (CPEP) on the coupled coefficient and the frequency offset. Based on the finite element method, we simulate numerically the evolution of the absorption spectra of the microstructure unit composed of a simply metal nanostructure. The simulated results show that two resonant absorption peaks are asymmetrical with the change of the coupling distance between the nano-elements. With the CPEP model, we not only explain successfully the asymmetrical behaviors of the peaks values of the absorption spectra with the change of the coupling distance but also obtain the resonant frequencies for different plasmons. The absorption spectra are simulated by the harmonic oscillator model, in which their calculated parameters originate from the CPEP model, and the results are very well association with those of the numerical simulation.

Rationale: The current outbreak of coronavirus disease (COVID-19) pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China, spreads across national and international borders. The overall death rate of COVID-19 pneumonia in the Chinese population was 4%. Objectives: To describe the process of hospitalization and critical care of patients who died of COVID-19 pneumonia. Methods: This was a multicenter observational study of 109 decedents with COVID-19 pneumonia from three hospitals in Wuhan. Demographic, clinical, laboratory, and treatment data were collected and analyzed, and the final date of follow-up was February 24, 2020. Results: The mean age of 109 decedents with COVID-19 pneumonia was 70.7 years, 35 patients (32.1%) were female, and 85 patients (78.0%) suffered from one or more underlying comorbidities. Multiple organ failure, especially respiratory failure and heart failure, appeared in all patients even at the early stage of disease. Overall, the mean time from onset of symptoms to death was 22.3 days. All 109 hospitalized patients needed admission to an intensive care unit (ICU); however, because of limited availability, only 51 (46.8%) could be admitted. The period from hospitalization to death in the ICU group and non-ICU group was 15.9 days (standard deviation = 8.8 d) and 12.5 days (8.6 d, P = 0.044), respectively. Conclusions: Mortality due to COVID-19 pneumonia was concentrated in patients above the age of 65 years, especially those with major comorbidities. Patients who were admitted to the ICU lived longer than those who were not. Our findings should aid in the recognition and clinical management of such infections, especially with regard to ICU resource allocation.

Since the outbreak of coronavirus disease 2019 (COVID-19) in China in December 2019, considerable attention has been focused on its elucidation. However, it is also important for clinicians and epidemiologists to differentiate COVID-19 from other respiratory infectious diseases such as influenza viruses.The aim of this study was to explore the different clinical presentations between COVID-19 and influenza A (H1N1) pneumonia in patients with ARDS.This analysis was a retrospective case-control study. Two independent cohorts of patients with ARDS infected with either COVID-19 (n = 73) or H1N1 (n = 75) were compared. Their clinical manifestations, imaging characteristics, treatments, and prognosis were analyzed and compared.The median age of patients with COVID-19 was higher than that of patients with H1N1, and there was a higher proportion of male subjects among the H1N1 cohort (P .05). Patients with COVID-19 exhibited higher proportions of nonproductive coughs, fatigue, and GI symptoms than those of patients with H1N1 (P .05). Patients with H1N1 had higher Sequential Organ Failure Assessment (SOFA) scores than patients with COVID-19 (P .05). The PaoThere were many differences in clinical presentations between patients with ARDS infected with either COVID-19 or H1N1. Compared with H1N1 patients, patients with COVID-19-induced ARDS had lower severity of illness scores at presentation and lower SOFA score-adjusted mortality.

We propose a coupling model to describe the interaction between the bright and dark modes of the plasmons of a dimer composed of two orthogonal gold nano-rods (GNRs), referred to as the BDMC model. This model shows that the eigen-frequencies of the coupled plasmons are governed by Coulomb potential and electrostatic potential. With the BDMC model, the behaviors of the coupling coefficient and the frequency offset, which is a new parameter introduced here, are revealed. Meanwhile, the asymmetric behavior of two eigen-frequencies related to gap of two GNRs is explained. Using the harmonic oscillator model and the coupled parameters obtained by the BDMC model, the bright mode absorption spectra of the dimer are calculated and the results agree with the numerical simulation.