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Optically stimulated luminescence of Dy^3+-doped NaCaPO4 glass-ceramics

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Journal of Rare Earths 2020年第9期38卷 927-932,I0001页

作者： Jie Xu Zhaoyang Chen Minqiang gai Yanwei Fan Chengfa He Key Laboratory of Functional Materials and Devices for Special Environments of CAS Xinjiang Key Laboratory of Electronic Information Materials and DevicesXinjiang Technical Institute of Physics and Chemistry of CASUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Solid State Radiation Physics Urumqi 830011China

Dy^3+-doped glass-ceramics containing NaCaPO4 crystals were successfully fabricated by heat treatment at base glass,and the luminescence properties were investigated for potential applications in radiation *** photo luminescence(PL)excitation and emission spectra exhibit transitions related to Dy^3+ions corresponding to the strongest excitation and emission wavelengths at 351 and 575 nm,*** CW-OSL properties as a function of dopant concentration,pre-heating temperature,pre-heating time and signal fading were *** most appropriate Dy^3+ion concentration was found to be 0.25 mol%.The TL glow curves have a broad peak feature peaking at 195±5℃.The fading of the OSL signal would keep stable in five days with the intensity value of about 76.11%.The samples also exhibit good signal reusability and a broad linear dose response range(0.02-1000 Gy).

关键词： Optically stimulated luminescence Glass-ceramics Radiation measurements Photoluminescence Rare earths

Zircon U-Pb ages of the two-periods magmatism from the Xiuwacu Mo-W-Cu deposit, northwest Yunnan, China

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China Geology 2019年第3期2卷 391-392页

作者： yong-gao Huang Chang-li Xiong Xiao-chuan Jia Xue-jun Yang gai Luo Guilin University of Technology Guilin 541004China Sichuan Geological Survey Chengdu 610081China Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resource Key Laboratory of Sichuan Province Chengdu 610081China

The Xiuwacu deposit is a large magmatic hydrothermal Mo-W-Cu deposit, and also a typical representative of the late Triassic mineralization in Geza Arc (Lai AQ et al., 2016;Liu XL et al., 2017). The Xiuwacu pluton intruded into the Lamaya Formation, and contains two periods of rocks bounded by intrusive contact. Nonetheless, most of the intrusive boundaries were superposed by later fault structures.

关键词： magmatic Lamaya Geza

Modeling ε Eri and Asteroseismic Tests of Element Diffusion

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 591-602页

作者： Ning gai Shao-Lan Bi Yan-Ke Tang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Department of Astronomy Beijing Normal University Beijing 100875 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Taking into account the helium and metal diffusion, we explore the possible evolutionary status with a seismic analysis, of the MOST （Microvariability and Oscillations of STars） target： the star e Eri. We adopt different input parameters to construct models to fit the available observational constraints in, e.g., Teff, L, R and [Fe/H]. From the computation we obtain the average large spacings of e Eri to be about 194 ± 1μHz. The age of the diffused models was found to be about 1 Gyr, which is younger than the age determined previously by models without diffusion. We found that the effect of pure helium diffusion on the internal structure of the young low-mass star is slight, but that of metal diffusion is obvious. The metal diffusion leads the models to have much higher temperature in the radiative interior, and, correspondingly a higher sound speed there, hence a larger frequency and spacings.

关键词： stars evolution - stars interiors -stars individual ∈ Eridani

Multi-example feature-constrained back-projection method for image super-resolution

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Computational Visual Media 2017年第1期3卷 73-82页

作者： Junlei Zhang Dianguang gai Xin Zhang Xuemei Li School of Computer Science and Technology Shandong University Earthquake Administration of Shandong Province

Example-based super-resolution algorithms,which predict unknown high-resolution image information using a relationship model learnt from known high- and low-resolution image pairs, have attracted considerable interest in the field of image processing. In this paper, we propose a multi-example feature-constrained back-projection method for image super-resolution. Firstly, we take advantage of a feature-constrained polynomial interpolation method to enlarge the low-resolution image. Next, we consider low-frequency images of different resolutions to provide an example pair. Then, we use adaptive k NN search to find similar patches in the low-resolution image for every image patch in the high-resolution low-frequency image, leading to a regression model between similar patches to be learnt. The learnt model is applied to the low-resolution high-frequency image to produce high-resolution high-frequency information. An iterative back-projection algorithm is used as the final step to determine the final high-resolution *** results demonstrate that our method improves the visual quality of the high-resolution image.

关键词： feature constraints back-projection super-resolution(SR)

Progesterone promotes neuronal differentiation of human umbilical cord mesenchymal stem cells in culture conditions that mimic the brain microenvironment

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Neural Regeneration Research 2012年第25期7卷 1925-1930页

作者： Xianying Wang Honghai Wu gai Xue Yanning Hou Hebei Medical University Shijiazhuang 050017 Hebei Province China The Third Hospital of Hebei Medical University Shijiazhuang 050051 Hebei Province China Bethune Intemational Peace Hospital of Chinese PLA Shijiazhuang 050082 Hebei Province China

In this study, human umbilical cord mesenchymal stem cells from full-term neonates born by vagina delivery were cultured in medium containing 150 mg/mL of brain tissue extracts from Sprague-Dawley rats （to mimic the brain microenvironment）. Immunocytochemical analysis demonstrated that the cells differentiated into neuron-like cells. To evaluate the effects of progesterone as a neurosteroid on the neuronal differentiation of human umbilical cord mesenchymal stem cells, we cultured the cells in medium containing progesterone （0.1, 1, 10 pM） in addition to brain tissue extracts. Reverse transcription-PCR and flow cytometric analysis of neuron specific enolase-positive cells revealed that the percentages of these cells increased significantly following progesterone treatment, with the optimal progesterone concentration for neuron-like differentiation being 1 tJM. These results suggest that progesterone can enhance the neuronal differentiation of human umbilical cord mesenchymal stem cells in culture medium containing brain tissue extracts to mimic the brain microenvironment.

关键词： progesterone mesenchymal stem cells neuron differentiation brain tissue extracts neural regeneration

A Ten-year Retrospective Study of Invasive Candidiasis in a Tertiary Hospital in Beijing

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Biomedical and Environmental Sciences 2021年第10期34卷 773-788页

作者： YANG Zhi Hui SONG Ying gai LI Ruo Yu Department of Dermatology and Venerology Beijing Key Laboratory of Molecular Diagnosis of DermatosesNational Clinical Research Center for Skin and Immune DiseasesNMPA Key Laboratory for Quality Control and Evaluation of CosmeticsPeking University First HospitalBeijing 100034China

Objective This study aimed to evaluate the epidemiological,clinical and mycological characteristics of invasive candidiasis(IC)in *** A ten-year retrospective study including 183 IC episodes was conducted in a tertiary hospital in Beijing,*** The overall incidence of IC from 2010–2019 was 0.261 episodes per 1,000 ***(71.0%)was the major infective pattern;70.3%of the patients tested positive for Candida *** before IC and the median time to develop an invasive infection after colonization was13.5 days(interquartile range:4.5–37.0 days).Candida albicans(45.8%)was the most prevalent species,followed by Candida parapsilosis(19.5%),Candida glabrata(14.2%)and Candida tropicalis(13.7%).***-albicans IC was more common in patients with severe anemia(P=0.018),long-term hospitalization(P=0.015),hematologic malignancies(P=0.002),continuous administration of broad-spectrum antibiotics(P<0.001)and mechanical ventilation(P=0.012).In vitro resistance testing showed that11.0%of the Candida isolates were resistant/non-wild type(non-WT)to fluconazole,followed by voriconazole(9.6%),micafungin(3.8%),and caspofungin(2.9%).Fluconazole was the most commonly used drug to initiate antifungal therapy both before and after the proven diagnosis(52.6%and 54.6%,respectively).The 30-day and 90-day all-cause mortality rates were 24.5%and 32.7%,*** The incidence of IC has declined in the recent five ***-albicans contributed to more than half of the IC *** can be used as first-line therapy if resistant strains are not ***,multi-center surveillance of the clinical and mycological characteristics of IC is required.

关键词： Invasive candidiasis Epidemiology Risk factors Antifungal resistance Treatment Mortality

Excited-state Intramolecular Proton Transfer Mechanisms of Thiazole-based Chemosensor: a TD-DFT Study

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1933-1940页

作者： CAO Hu LIU gai-Mei CAI Jia WANG Yan School of Chemistry and Environmental Engineering Hubei Minzu UniversityEnshi 445000China Key Laboratory of Magnetic Resonance in Biological Systems National Center for Magnetic Resonance in WuhanState Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China

The excited-state intramolecular proton transfer(ESIPT) mechanisms of 2-(2-hydroxyphenyl)-4-phenylthiazole(HPT) and 2-(5-bromo-2-hydroxyphenyl)-4-phenylthiazole(BrHPT) have been systematically investigated by density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods, approaching along with the polarizable continuum model(PCM). The calculated primary bond lengths and bond angles demonstrate that HPT and BrHPT can form intramolecular hydrogen bonds in the ground state(S0), which can be significantly strengthened in the first excited state(S1). Our calculated results well reproduce the experimental absorption and emission spectra. Upon addition of F-, the proton can move close to F-and the hydroxy moieties are deprotonated, which cause a red-shift in absorption and a new emission peak in fluorescence emission with the disappearance of the dual fluorescence emission. The calculated Mulliken’s charge distribution and frontier molecular orbitals further demonstrate that the ESIPT processes are more likely to occur in the S1 state. The constructed potential energy curves of the S0 and S1 states confirm that the proton transfer processes are hard to occur in the S0 state due to the high energy barriers. Moreover, much lower energy barriers are found in the S1 state, which proves that the ESIPT processes are more likely to take place in the S1 state. In addition, compound with electron withdrawing(-Br) group might result in much stronger intramolecular hydrogen bond and owns lower energy barrier, which can facilitate the ESIPT processes.

关键词： density functional theory ESIPT 2-(2-hydroxy-phenyl)-4-phenylthiazole potential energy curves

Spatial variations in daily average CO_2 concentrations above wetland surface of Xianghai National Nature Reserve, China

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Journal of Environmental Sciences 2005年第1期17卷 54-58页

作者： BAIJun-hong OUYANGHua WANGQing-gai ZHOUCai-ping XUXiao-feng InstituteofGeographicalSciencesandNaturalResourcesResearch ChineseAcademyofSciencesBeijing100101China

Horizontal and vertical variations of daily average CO 2 concentration above the wetland surface were studied in Xianghai National Nature Reserve of China in August, 2000 The primary purpose was to study spatial distribution characteristics of CO 2 concentration on the four levels of height(0 1 m, 0 6 m, 1 2 m and 2 m) and compare the differences of CO 2 concentration under different land covers. Results showed that daily average CO 2 concentration above wetland surface in Xianghai National Natural Reserve was lower than that above other wetlands in northeast China as well as the worldwide average, suggesting that Xianghai wetland absorbed CO 2 in August and acted as “sink” of CO 2 The horizontal variations on the four levels of height along the latitude were distinct, and had the changing tendency of “decreasing after increasing” with the increase of height. The areas with obvious variations were consistent on different levels of height, and those with the highest variations appeared above surface of shore, sloping field, Typha wetland and Phragmites wetland; the vertical variations were greatly different, with the higher variations in Phragmites wetland and Typha wetland, and the lands near the shore and the sloping field with the lower variations. Spatial variations of daily average CO 2 concentrations above wetland surface were affected by surface qualities and land covers.

关键词： wetland surface daily average CO_2 concentration sink horizontal variation vertical variation

Quantitative genetic studies with applications in plant breeding in the omics era

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The Crop Journal 2020年第5期8卷 683-687页

作者： Jiankang Wang JoséCrossa Junyi gai Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China International Maize and Wheat Improvement Center(CIMMYT) Carretera Mexico-Veracruz Km.45El BatanTexcocoMexico Soybean Research Institute Nanjing Agricultural UniversityNanjing 210095JiangsuChina

Quantitative genetics is concerned with the inheritance of biological traits showing continuous(or quantitative)phenotypic *** traits are common and have been extensively investigated and studied in evolutionary and genetic studies and in plant and animal *** traits are normally controlled by multiple genes with various kinds of genetic effect,and their phenotypes are readily modified by environmental variation.

关键词： breeding inheritance traits