1,753 research outputs found

    Strong enhancement of chlorophyll a concentration by a weak typhoon

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    Recent studies demonstrate that chlorophyll a (chl a) concentrations in the surface ocean can be significantly enhanced due to typhoons. The present study investigated chl a concentrations in the middle of the South China Sea (SCS) from 1997-2007. Only the Category1 (minimal) Typhoon Hagibis (2007) had a notable effect on the chl a concentrations. Typhoon Hagibis had a strong upwelling potential due to its location near the equator, and the forcing time of the typhoon (>82 h) was much longer than the geostrophic adjustment time (~63 h). The higher upwelling velocity and the longer forcing time increased the depth of the mixed-layer, which consequently induced a strong phytoplankton bloom that accounted for about 30% of the total annual chl a concentration in the middle of the SCS. The implication is that the forcing time of a typhoon should be long enough to establish a strong upwelling and consequently for the induction of significant upper ocean responses.Comment: Typhoon-Ocean Environment interaction

    Unveiling Patterns and Colors in Architectural Paintings: An Analysis by K-Means++ Clustering and Color Ratio Analysis

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    This study delves into the intricate world of patterns and colors found in architectural paintings within the illustrious Forbidden City. Through an in-depth analysis, we identified seven distinctive patterns, creating a pattern factor library that showcases five examples for each pattern category. To extract the color schemes of each architectural painting type, we employed the K-Means++ algorithm for secondary clustering. Utilizing both RGB and HSV color space models, we examined scatter diagrams and histograms for three specific architectural color paintings. The results revealed a balanced distribution of warm and cool colors across all three architectural painting types. The prevalent colors observed in the Forbidden City architectural paintings were red, yellow, cyan, and blue, exhibiting low levels of saturation and moderate to high levels of brightness, evoking a serene and luminous ambiance. Through color ratio analysis, we established traditional color names that corresponded to the extracted color values from each painting. Our findings suggest that the colors and patterns within the Forbidden City architectural paintings communicate a profound sense of tranquility and grandeur, aligning with the cultural and artistic values held during the Ming and Qing dynasties

    T-cell lymphoblastic lymphoma presenting with pleural effusion: A case report

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    AbstractAdult lymphoblastic lymphoma (LBL) is an aggressive form of non-Hodgkin lymphoma occurring in predominantly adolescent and young adult men, accounting for 1% to 2% of all non-Hodgkin's lymphomas. In contrast to B-LBL, T-cell LBL is much more common, accounting for up to 90% of disease in adults. Mediastinal mass, pleural and/or pericardial effusions are the major characteristics of T-LBL. We report an 18-year-old male with a pleural effusion, mediastinal mass, a light pericardial effusion, and a normal hemogram. The cytology of the pleural effusion initially suggested malignancy, but definitive diagnosis was unclear. After a medical thoracoscopy, the partial pleura was picked and immunophenotypic study revealed the following: CD3+, TdT+, CD99+, CD20−. The patient was finally diagnosed with T-LBL and died only 6 months after that. The case highlight the point that medical thoracoscopy is a safe and accurate diagnostic procedure for pleural diseases, and partial pleura biopsy with immunophenotyping was essential for achieving the correct diagnosis of LBL

    Mass spectra of bottom-charm baryons

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    In this paper, we investigate the mass spectra of bottom-charm baryons systematically, where the relativistic quark model and the infinitesimally shifted Gaussian basis function method are employed. Our calculation shows that the ρ\rho-mode appears lower in energy than the other excited modes. According to this feature, the allowed quantum states are selected and a systematic study of the mass spectra for Ξbc\Xi_{bc}^{'} (Ξbc\Xi_{bc}) and Ωbc\Omega_{bc}^{'} (Ωbc\Omega_{bc}) families is performed. The root mean square radii and quark radial probability density distributions of these baryons are analyzed as well. Next, the Regge trajectories in the (J,M2)(J,M^{2}) plane are successfully constructed based on the mass spectra. At last, we present the structures of the mass spectra, and analyze the difficulty and opportunity in searching for the ground states of bottom-charm baryons in experiment.Comment: 19 pages, 9 figures, 6 tables. arXiv admin note: text overlap with arXiv:2210.1308

    Mass spectra of double-bottom baryons

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    Based on the relativistic quark model and the infinitesimally shifted Gaussian basis function method, we investigate the mass spectra of double bottom baryons systematically. In the ρ\rho-mode which appears lower in energy than the other excited modes, we obtain the allowed quantum states and perform a systematic study of the mass spectra of the Ξbb\Xi_{bb} and Ωbb\Omega_{bb} families. We analyze the root mean square radii and quark radial probability density distributions to deeply understand the structure of the heavy baryons. Meanwhile, the mass spectra allow us to successfully construct the Regge trajectories in the (J,M2)(J,M^{2}) plane. We also predict the masses of the ground states of double bottom baryons and discuss the differences between the structures of our spectra and those from other theoretical methods. At last, the shell structure of the double bottom baryon spectra is shown, from which one could get a bird's-eye view of the mass spectra.Comment: 16 pages, 9 figures, 5 tables. arXiv admin note: text overlap with arXiv:2207.0416

    Topological magnons in one-dimensional ferromagnetic Su-Schrieffer-Heeger model with anisotropic interaction

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    Topological magnons in a one-dimensional (1D) ferromagnetic (FM) Su-Schrieffer-Heeger (SSH) model with anisotropic exchange interactions are investigated. Apart from the inter-cellular isotropic Heisenberg interaction, the intercellular anisotropic exchange interactions, i.e. Dzyaloshinskii-Moriya interaction (DMI) and pseudo-dipolar interaction (PDI), also can induce the emergence of the non-trivial phase with two degenerate in-gap edge states separately localized at the two ends of the 1D chain, while the intracellular interactions instead unfavors the topological phase. The interplay among them has synergistic effects on the topological phase transition, very different from that in the two-dimensional (2D) ferromagnet. These results demonstrate that the 1D magnons possess rich topological phase diagrams distinctly different from the electronic version of the SSH model and even the 2D magnons. Due to the lower dimensional structural characteristics of this 1D topological magnonic system, the magnonic crystals can be constructed from bottom to top, which has important potential applications in the design of novel magnonic devices.Comment: 22 pages, 11 figure
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