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Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid-glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition.
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Fluorescence imaging is conducive to establish a bridge between molecular biology and clinical medicine, and provides new tools for disease process research, early diagnosis, and efficacy evaluation, because of the advantages of rapid imaging and nondestructive detection. Herein, a series of fluorescent molecules with thiadiazole, or thiazole, or benzothiazole cores were designed and synthesized to develop more excellent fluorescent molecules in bio-imaging. According to theoretical and experimental methods, we found that benzothiazole derivative 14 B with conjugate expansion by (4-aminophenyl) ethynyl group was the most excellent fluorescent molecule among all the investigated compounds and exhibited low cytotoxicity and strong blue and green fluorescence by confocal cell imaging.
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Benzotiazoles , Tiadiazoles , Benzotiazoles/química , Colorantes , Fluorescencia , Colorantes Fluorescentes/químicaRESUMEN
Acupuncture has already been extensively utilized to treat high blood pressure (hypertension) in several nations. Nevertheless, the bibliometric research on the worldwide usage of acupuncture for hypertension is mostly unclear. As a result, our objective for the research aimed to investigate the present state as well as developments in the global usage of acupuncture on hypertension during the last 20 years using CiteSpace (5.8.R2). The Web of Science (WOS) database examined papers on acupuncture treatment of hypertension from 2002 to 2021. We examined the number of publications, cited journals, nations/regions, organizations, authors, cited authors, cited references, and keywords utilizing CiteSpace. The record of 296 documents was obtained between 2002 and 2021. The quantity and frequency of annual publications rose gradually. Regarding frequency and centrality of citations, Circulation and Clin Exp Hypertens (Clinical and Experimental Hypertension) scored top and second respectively. China had the most publications among countries/regions, as well as the five largest institutions were also in China. Cunzhi Liu was the most productive author, while P Li was the most referenced author. XF Zhao produced the first article inside the quantity of cited references classification. 'Electroacupuncture' had a significant frequency with centrality for the keywords, which suggested electroacupuncture is a popular treatment in this field. In the treatment of hypertension, electroacupuncture has a beneficial effect on reducing blood pressure. However, because of the many different applications of electroacupuncture frequencies in research, whether the electroacupuncture frequency is connected to the therapeutic impact should be given more significant consideration. The findings of this bibliometric analysis give an overview of the present state as well as developments of clinical studies on acupuncture for hypertensive patients during the last two decades, which could assist researchers in identifying hot subjects and exploring novel directions in further study within the field.
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How glasses relax at room temperature is still a great challenge for both experimental and simulation studies due to the extremely long relaxation time-scale. Here, by employing a modified molecular dynamics simulation technique, we extend the quantitative measurement of relaxation process of metallic glasses to room temperature. Both energy relaxation and dynamics, at low temperatures, follow a stretched exponential decay with a characteristic stretching exponent ß = 3/7, which is distinct from that of supercooled liquid. Such aging dynamics originates from the release of energy, an intrinsic nature of out-of-equilibrium system, and manifests itself as the elimination of defects through localized atomic strains. This finding is also supported by long-time stress-relaxation experiments of various metallic glasses, confirming its validity and universality. Here, we show that the distinct relaxation mechanism can be regarded as a direct indicator of glass transition from a dynamic perspective.
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OBJECTIVE: According to 73 patients with middle clavicle fracture treated conservatively, a new classification of middle clavicle fracture was proposed, and the clinical effect of plastic splint in the treatment of middle clavicle fracture was observed. METHODS: Total 73 patients with middle clavicle fracture treated with plastic splint from September 2018 to August 2020 were analyzed retrospectively. All the patients were divided into 4 types according to the degree of fracture displacement. There were 16 cases of typeâ , including 7 males and 9 females, ranging in age from 18 to 37 years old, with a mean of (28.6±7.8) years old;12 cases of mild disease, 3 cases of moderate disease and 1 case of severe disease. There were 16 cases of type â ¡, including 6 males and 10 females, ranging in age from 25 to 49 years old, with a mean of (37.3±9.4) years old;5 cases of mild disease, 8 cases of moderate disease and 3 cases of severe disease. There were 7 cases of type â ¢, including 4 males and 3 females, ranging in age from 33 to 57 years old;2 cases of mild disease, 3 cases of moderate disease and 2 cases of severe disease. There were 34 cases of type â £, including 16 males and 18 females, ranging in age from 48 to 82 years old, with a mean of(66.4±14.9) years old;7 cases of mild disease, 17 cases of moderate disease and 10 cases of severe disease. All patients received plastic splint external fixation for 4 weeks. Visual analgue scale (VAS) and Constant-Murley shoulder scores before treatment and 1, 3 and 9 months after treatment were observed and recorded to evaluate the change of pain degree and shoulder function recovery before and after treatment. The patients' satisfaction with the appearance after treatment was recorded at the latest follow-up. The X-ray findings at the latest follow-up were used to judge whether the patient had fracture nonunion. And according to the fracture healing time and imaging findings, the excellent and good rate of clinical curative effect in patients with different types was obtained. RESULTS: All patients were followed up, and the duration ranged from 9 to 11 months, with a mean of (9.8±0.7) months. The VAS scores of typeâ , typeâ ¡and type â £ before treatment were 2.88±0.83, 3.67±0.80 and 6.92±1.71 respectively, which were decreased to 0.54±0.19, 0.77±0.25 and 1.18±0.17 respectively after 9 months of treatment. The Constant-Murley shoulder scores of typeâ , typeâ ¡and type â £ were 65.81±2.09, 63.50±2.22 and 47.93±2.91 respectively before treatment, and increased to 88.56±2.11, 85.12±2.23 and 71.25±2.16 respectively after 9 months of treatment. Five patients were not satisfied with the appearance after treatment;6 patients had no obvious continuous callus passing through after 9 months of treatment, which was fracture nonunion. CONCLUSION: The classification of middle clavicle fracture is more appropriate to the clinic, which has a certain clinical guiding significance for the selection of treatment methods and prognosis of middle clavicle fracture. Plastic splint is effective in the treatment of middle clavicle fracture without obvious displacement and overlapping displacement, and the incidence of complications is low. It can be popularized in clinic.
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Clavícula , Férulas (Fijadores) , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Placas Óseas , Clavícula/diagnóstico por imagen , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Masculino , Persona de Mediana Edad , Plásticos , Estudios Retrospectivos , Adulto JovenRESUMEN
Src homology-2 domain-containing protein tyrosine phosphatase 1 (SHP1) is mainly restricted to hematopoietic and epithelial cells and widely accepted as a convergent node for oncogenic cell-signaling cascades. The development of efficient methods for rapidly tracing and inhibiting the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of the related disease. With this aim, we designed and synthesized five 2-phenyl-1,3,4-thiadiazole derivatives (PT2, PT5, PT8, PT9 and PT10) here based on the reported SHP1 inhibitors (PT1, PT3, PT4, PT6 and PT7). The photophysical properties and inhibitory activities of these 2-phenyl-1,3,4-thiadiazole derivatives (PT1-PT10) against SHP1 were thoroughly studied from the theoretical simulation and experimental application aspects. The representative compound PT10 exhibited a larger quantum yield than the other molecules because of the smaller geometric relaxation and reorganization energy of the excited state, which was consistent with the results from the fluorescence experiments in organic solvents. In addition, PT10 showed a selective fluorescence response for SHP1 activity and low cytotoxicity in HeLa cells. Lastly, it indicated the potential application in two-photon cell fluorescence imaging in the future according to the calculated excellent two-photon absorption properties. In this contribution, firstly, we offered the fluorescent and activated molecule PT10 against SHP1, which achieved the integration of visualization and inhibitory activity of SHP1 preliminarily at the enzyme molecular level.
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Teoría Funcional de la Densidad , Inhibidores Enzimáticos/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 6/antagonistas & inhibidores , Tiadiazoles/farmacología , Inhibidores Enzimáticos/química , Células HeLa , Humanos , Estructura Molecular , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Tiadiazoles/químicaRESUMEN
Despite the importance of glass forming ability as a major alloy characteristic, it is poorly understood and its quantification has been experimentally laborious and computationally challenging. Here, we uncover that the glass forming ability of an alloy is represented in its amorphous structure far away from equilibrium, which can be exposed by conventional X-ray diffraction. Specifically, we fabricated roughly 5,700 alloys from 12 alloy systems and characterized the full-width at half-maximum, Δq, of the first diffraction peak in the X-ray diffraction pattern. A strong correlation between high glass forming ability and a large Δq was found. This correlation indicates that a large dispersion of structural units comprising the amorphous structure is the universal indicator for high metallic glass formation. When paired with combinatorial synthesis, the correlation enhances throughput by up to 100 times compared to today's state-of-the-art combinatorial methods and will facilitate the discovery of bulk metallic glasses.
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Aleaciones , Vidrio , Aleaciones/química , Vidrio/química , Difracción de Rayos XRESUMEN
By decreasing the rate of physical vapor deposition, ZrCuAl metallic glasses with improved stability and mechanical performances can be formed, while the microscopic structural mechanisms remain unclear. Here, with scanning transmission electron microscopy and high-energy synchrotron X-ray diffraction, we found that the metallic glass deposited at a higher rate exhibits a heterogeneous structure with compositional fluctuations at a distance of a few nanometers, which gradually disappear on decreasing the deposition rate; eventually, a homogeneous structure is developed approaching ultrastability. This microscopic structural evolution suggests the existence of the following two dynamical processes during ultrastable metallic glass formation: a faster diffusion process driven by the kinetic energy of the depositing atoms, which results in nanoscale compositional fluctuations, and a slower collective relaxation process that eliminates the compositional and structural heterogeneity, equilibrates the deposited atoms, and strengthens the local atomic connectivity.
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OBJECTIVE: To study a Chinese pedigree with Hailey-Hailey disease (HHD) and identify the ATP2C1 gene mutation in this family. METHODS: All exons of the ATP2C1 gene were analyzed with polymerase chain reaction and DNA sequencing in all patients of this family and 80 unrelated population-matched controls. RESULTS: We identified a nonsense mutation 163C to T, resulting in a premature termination codon in ATP2C1 gene. The mutation was not found in normal individuals of the family and controls. CONCLUSION: The mutation can affect the result of transcription and translation of ATP2C1 gene, and it is firstly reported in the Chinese pedigree with HHD.