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Precision frequency Measurement of ^(87)Rb 5S_(1/2)(f=2)→5D_(5/2)(f″=4)Two-Photon Transition through a fiber-Based Optical frequency Comb

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Chinese Physics Letters 2016年第5期33卷 30-34页

作者：夏巍戴少阳张胤李坤乾于齐陈徐宗 Institute of Quantum Electronics School of Electronics Engineering and Computer SciencesPeking University Jiangsu Key Laboratory on Opto-electronic Technology School of Physics and TechnologyNanjing Normal University

The absolute frequency of 87Rb 5S1/2 （f=2）→5D5/2 （f＂ = 4） two-photon transition at 778nm is measured in an accuracy of 44kHz. A home-made erbium-doped fiber laser frequency comb with frequency stability of 5.0 × 10-13@1 s is employed for the light source. By using a periodically poled lithium niobate, the femtosecond pulse operating in 1556 nm is frequency-doubled to 778 nm to obtain the direct two-photon transition spectroscopy of thermal rubidium vapor. Through sweeping the carrier envelope offset frequency （fceo）, the 5S1/2 （f=2）→5D5/2 （f＂ = 4） two-photon transition line is clearly resolved and its absolute frequency is determined via the peak-finding of the fitting curve. After the frequency correction, the measured result agrees well with the previous experiment on this transition. The entire potential candidate of optical frequency standard for system configuration is compact and robust, providing a telecommunication applications.

关键词： Precision frequency Measurement of in is f=2 on as been Rb 5S f Two-Photon Transition through a fiber-Based Optical frequency Comb

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The Mechanism for Mimicry: Instant Biosemiotic Selection or Gradual Darwinian fine-Tuning Selection?

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BIOSEMIOTICS 2019年第1期12卷 39-55页

作者： Alexander, V. N. Dactyl Fdn 64 Grand St New York NY 10013 USA US Dept State Fulbright Specialist Program Bur Educ & Cultural Affairs Washington DC 20520 USA

Biological mimicry is regarded by many as a textbook illustration of Darwin's idea of evolution by random mutation followed by differential selection of reproductively fit specimens, resulting in gradual phenotypic change in a population. In this paper, I argue that some cases of so-called mimicry are probably merely look-a-likes and do not gain an advantage due to their similarity in appearance to something else. In cases where a similar appearance does provide a benefit, I argue that it is possible that these forms of mimicry were created in a single generation. An interpretive response to an appearance as a sign can make a new structure perform drastically differently in an environment. In such cases, Darwin's natural selection mechanism only helps to explain gradual the spread of these new forms, not the creation of them. I argue that biosemiosis should be regarded as a much more powerful mechanism for affecting evolutionary trajectories than the gradualist view allows. I focus on two cases of butterfly mimicry: the Viceroy (Nymphalidae: Limenitis archippus) and Monarch (Nymphalidae: Danaus plexippus) butterflies, supposed Mullerian mimics, and deadleaf mimic butterflies (Kallima).

关键词： Saltationism Turing patterns Mimicry Pattern formation Genus Kallima Mimicry skepticism H f Nijhout

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Estimation of Uplift Pressure Equation at Key Points under floor of Hydraulic Structures

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COGENT ENGINEERING 2021年第1期8卷 Article: 1917287页

作者： Rasool, Mohammed Hamid Al-Maliki, Laheab A. Al-Mamoori, Sohaib Kareem Al-Ansari, Nadhir Univ Kufa Fac Phys Planning Dept Environm Planning Najaf Iraq Univ Al Qasim Green Fac Water Resources Engn Dept Management Water Resources Babylon Iraq Univ Al Qasim Green Fac Water Resources Engn Dept Hydraul Engn Struct Babylon Iraq Lulea Univ Technol Dept Civil Environm & Nat Resources Engn Lulea Sweden

Most of the hydraulic structures rest on an impervious foundation to reserve water at the upstream side. The water heads difference leads to water movement from the higher to the lower head through the porous soil layer beneath the foundation, generating an uplift pressure under the structure floor. In this study, a new method is presented to estimate the uplift pressures at key points by performing sub-surface flow analysis using the Analysis SYStem (ANSYS) software. Then a statistical analysis to validate the proposed equations is conducted using the SPSS software. The case study for this research is a barrage in Kufa city-Iraq. The used data to implement this study was water levels, soil permeability, and length of imperious foundation. The obtained results show good outcomes from using the proposed method to develop uplift pressure equations. The comparison of the current study results with Khosla's equation showed good agreement where the coefficient of determination (R-2) and the standard error of estimation (SEE) for the equations were between (99.9-97.8) and (0.024-0.11), respectively.

关键词： seepage statistical uplift pressures ANSYS f

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Data on ADME parameters of bisphenol A and its metabolites for use in physiologically based pharmacokinetic modelling

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DATA IN BRIEf 2023年 48卷 109101页

作者： Wisniowska, Barbara Linke, Susanne Polak, Sebastian Bielecka, Zofia Luch, Andreas Pirow, Ralph Jagiellonian Univ Fac Pharm Med Coll Med 9 St PL-30688 Krakow Poland German Fed Inst Risk Assessment BfR Dept Chem & Prod Safety Max Dohrn Str 8-10 D-10589 Berlin Germany Free Univ Berlin Inst Pharm Dept Biol Chem Pharm Berlin Germany Certara UK Ltd Simcyp Div Level 2 Acero1 Concourse Way Sheffield S1 2BJ England

Abbreviations: ADAM, advanced dissolution, absorption and metabolism;ADME, absorption, distribution, metabolism, excretion;AUC, area under the concentration-time curve;B/P ratio, blood-to-plasma concentration ratio;BPA, bisphenol A;BPAG, glucuronidated BPA;BPAS, sulfated BPA;BW, body weight;CES, carboxylesterase;Cmax, maximum concentra-tion in plasma;CLint, in vitro intrinsic clearance;CLiv , total intravenous clearance;CLperm, permeability clearance;CLrenal, renal clearance;CLint,bile, in vitro intrinsic biliary clearance;CLuint,G, net intrinsic metabolic clearance in the gut based on unbound BPA concentration;CL int,gutlumen, gut lumen intrinsic clearance;EHR, enterohepatic recirculation;fa, fraction absorbed;fugut, fraction of BPA unbound in the enterocyte;fuinc, fraction unbound in in vitro incubation;fumic, frac-tion unbound in microsomal incubation;fup, fraction unbound in plasma;fg, fraction of BPA escaping gut metabolism;HBD, number of hydrogen bond donors;HPGL, hepatocytes per gram of liver;IV, intravenous;IVIVE, in vitro to in vivo extrapolation;ka, absorption rate constant;Ka, acid dissociation constant;Km, Michaelis-Menten constant;Kp, tissue -to-plasma partition coefficient;MechPeff, mechanistic permeability;MPPGL, microsomal protein per gram of liver;MW, molecular weight;Qgut, hybrid parameter of blood flow and compound permeability through enterocytes;QSAR, quanti-tative structure-activity relationship;P , octanol:water partition coefficient;Papp, apparent permeability;Peff,man, effective intestinal permeability in human;PBPK, physiologically based pharmacokinetics;PSA, polar surface area;RAf, relative activity factor;rhUGT, recombinant human UGT;SULT, sulfotransferase;UGT, UDP-glucuronosyltransferase;Vmax, maxi-mum velocity;Vss, volume of distribution at steady-state.

关键词： BPA Bisphenol A PBPK ADME Modelling Oral route ADAM advanced dissolution, absorption and metabolism ADME absorption, distribution, metabolism, excretion AUC area under the concentration-time curve B/P ratio blood-to-plasma concentration ratio BPA bisphenol A BPAG glucuronidated BPA BPAS sulfated BPA BW body weight CES carboxylesterase C max maximum concentration in plasma CL int in vitro intrinsic clearance CL iv total intravenous clearance CL perm permeability clearance CL renal renal clearance CL int,bile in vitro intrinsic biliary clearance CLu int,G net intrinsic metabolic clearance in the gut based on unbound BPA concentration CL int,gutlumen gut lumen intrinsic clearance EHR enterohepatic recirculation f a fraction absorbed fu gut fraction of BPA unbound in the enterocyte fu inc fraction unbound in in vitro incubation fu mic fraction unbound in microsomal incubation fu p fraction unbound in plasma f g fraction of BPA escaping gut metabolism HBD number of hydrogen bond donors HPGL hepatocytes per gram of liver IV intravenous IVIVE in vitro to in vivo extrapolation k a absorption rate constant K a acid dissociation constant K m Michaelis-Menten constant K p tissue-to-plasma partition coefficient MechPeff mechanistic permeability MPPGL microsomal protein per gram of liver MW molecular weight Q gut hybrid parameter of blood flow and compound permeability through enterocytes QSAR quantitative structure-activity relationship P octanol:water partition coefficient P app apparent permeability P eff,man effective intestinal permeability in human PBPK physiologically based pharmacokinetics PSA polar surface area RAf relative activity factor rhUGT recombinant human UGT SULT sulfotransferase UGT UDP-glucuronosyltransferase V max maximum velocity V ss volume of distribution at steady-state

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Corrigendum to “Extreme contractive operators on Stone f -algebras” [Indag. Math. 25 (2014) 93–103]

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Indagationes Mathematicae 2017年第5期28卷 1109-1110页

作者： M.A. Ben Amor K. Boulabiar C. El Adeb Research Laboratory of Algebra Topology Arithmetic and Order Department of Mathematics Faculty of Mathematical Physical and Natural Sciences of Tunis Tunis-El Manar University 2092-El Manar Tunisia

There is a mistake in the proof of Lemma 4.2 of Ben Amor et al. (2014), and the corrected proof is provided in this Corrigendum note.

关键词： Stone f -algebra Stone operator Riesz homomorphism

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Expansion potential of novel skin grafts simulants with I-shaped auxetic incisions

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Biomedical Engineering Advances 2023年 5卷

作者： Vivek Gupta Arnab Chanda Centre for Biomedical Engineering Indian Institute of Technology (IIT) Delhi India Department of Biomedical Engineering All India Institute of Medical Sciences (AIIMS) Delhi India

Skin grafts play an important role in treatment of severe burn injuries. Split-thickness skin grafting is one of the most common grafting technique, in which, parallel incision patterns are projected onto a small portion of excised skin for generating expansions and covering a larger burn site. However, to date, expansions reported through experiments on such grafts, have been much lower than claimed, which inhibits their application in severe burn injury mitigation. In this work, novel skin graft simulants were developed to study the expansion potential of skin grafts with I-shaped auxetic incision patterns. A range of I-shape dimensional parameters were tested, and the effective Poisson's effect, meshing ratios, and generated stresses, biaxial deformation and stress were estimated across all skin graft simulants, with strain loadings up to 200%. High spacing between I-shaped unit cells, was found to generate high negative Poisson's ratio and meshing ratio (MR). With high spacing, lowest stresses were generated for the maximum edge lengths of the I-shape. Maximum negative Poisson's ratio of -1.12 and meshing ratio of 3.84 were produced by the skin graft simulants, indicating expansions much higher than traditional skin grafts. Such results have not been realized with skin grafts to date, which would be indispensable for further research into skin graft expansions and treatment of severe burn injuries.

关键词： Burns Skin graft Expansion Meshing ratio Auxetics A Cross-section Area f force kPa kilopascal L Length mm millimeter MR Meshing Ratio NPR Negative Poisson's Ratio PLA Polylactic Acid STL Stereolithography STSG Split Thickness Skin Grafting UTS Ultimate Tensile Strength UTM Universal Testing Machine 3 D Three Dimensional σ stress ε strain

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Quantifizierung von Glukosemetabolismus und Hypoxie mittels PET bei Kopf-Hals-Tumoren

Der Nuklearmediziner

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Der Nuklearmediziner 2020年第2期43卷 133-140页

作者： Sebastian Hoberück Klaus Zöphel Klinik und Poliklinik für Nuklearmedizin Universitätsklinikum Carl Gustav Carus TU Dresden Klinik und Poliklinik für Nuklearmedizin Klinikum Chemnitz gGmbH

The present article deals with the role of fDG- and hypoxia-PET in head and neck cancer. The focus lays on the multitudinously different methods of quantification and their valence in clinical routine and research. fDG PET does not necessarily require a quantitative analysis. However, hypoxia PET imaging typically suffers from a low contrast compared to fDG which hampers pure qualitative analysis. Hypoxia tracers advantageously show a strict one-dimensional uptake / retention, while the accumulation in tumor cells of the high-contrast tracer fDG is driven by several factors. There is a variety of further quantitative parameters beside the apparently omnipresent but debatable maximum standardized uptake value (SUV

关键词： PET Quantifizierung Kopf Hals Tumore fDG f MISO Hypoxie PET quantification HNSCC fDG f MISO hypoxia

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A water-soluble and reversible fluorescent probe for Al³⁺ and f^- in living cells

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SENSORS AND ACTUATORS B-CHEMICAL 2016年 229卷 138-144页

作者： Diao, Quanping Ma, Pinyi Lv, Linlin Li, Tiechun Sun, Ying Wang, Xinghua Song, Daqian Jilin Univ Coll Chem Qianjin St 2699 Changchun 130012 Peoples R China Anshan Normal Univ Sch Chem & Life Sci Pingan St 43 Anshan 114005 Peoples R China

Based on fluorescein, a novel water-soluble and reversible fluorescent probe (flu-Py) was designed and synthesized for the sequentially "ON-Off-ON" fluorescent detection of Al3+ and f- in concentration range of 0-10 mu mol L-1 and 0-30 mu mol L-1, respectively, with high sensitivity and excellent selectivity. The detection limits for Al3+ and f- were 0.092 mu mol L-1 and 0.1 1 2 mu mol L-1, respectively. The binding mode and sensing mechanism of flu-Py with Al3+ was verified by density functional theory (DfT) and time dependent density functional theory (TDDfT) calculation. The "ON-Off-ON" fluorescent property of flu-Py upon the addition of Al3+ and f- was utilized for the imaging of living cells. (C) 2016 Elsevier B.V. All rights reserved.

关键词： fluorescence Probe fluorescein Al3+ f Living cells

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Nuklearmedizinische Bildgebung bei infektiöser Endokarditis und Device-Infektionen

Der Nuklearmediziner

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Der Nuklearmediziner 2020年第1期43卷 47-56页

作者： Oliver Lindner Institut für Radiologie Nuklearmedizin und Molekulare Bildgebung Herz- und Diabeteszentrum NRW Universitätsklinik der Ruhr-Universität Bochum

Infective endocarditis (IE) is a life-threatening disease. Due to increasing numbers of diagnostic and therapeutic procedures as well as cardiac device implantations, the prevalence of IE is rising. The diagnosis of IE is complex and based on clinical findings, microbiology, and imaging. After a revision of the ESC endocarditis guideline in 2015, In addition, Nuclear medicine imaging of IE requires special patient preparation and knowledge of specific pitfalls resulting from attenuation correction and physiological reaction to foreign body material.

关键词： Endokarditis Diagnostik f fDG PET CT Leukozyten SPECT CT Endocarditis diagnosis f fDG PET CT leucocyte SPECT CT

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不同类型甜瓜亲本及其f1代果实挥发性物质成分的比较

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北方园艺 2017年第23期 34-41页

作者：王硕硕巩彪陈媛媛荆鑫刘鑫史庆华聂文婧山东农业大学园艺科学与工程学院山东泰安271018

以野生薄皮甜瓜("马泡",杂交父本)、厚皮网纹甜瓜(杂交母本)和二者杂交的f1代果实为试材,利用气相色谱-质谱联用(GC-MS)技术检测其成熟果实中挥发性物质的种类和相对含量的差异。结果表明:网纹厚皮甜瓜、野生甜瓜和f1检测到... 详细信息

以野生薄皮甜瓜("马泡",杂交父本)、厚皮网纹甜瓜(杂交母本)和二者杂交的f1代果实为试材,利用气相色谱-质谱联用(GC-MS)技术检测其成熟果实中挥发性物质的种类和相对含量的差异。结果表明:网纹厚皮甜瓜、野生甜瓜和f1检测到的挥发性物质成分分别为50、70、79种,3个不同类型甜瓜的果实中共检测出120种挥发性物质,其中包括58种酯类、10种醇类、4种醛类、12种烯类和36种其它物质;3个类型甜瓜的果实中共同含有的挥发性物质有23种。3个类型甜瓜的果实中主要的挥发性物质均为酯类物质,但种类和相对含量存在差异。其中f1代挥发性物质最为丰富,表明挥发性物质的种类具有超亲优势的潜力,该结果为研究甜瓜挥发性物质代谢提供一定的参考依据。

关键词：甜瓜 f 代挥发性物质气相色谱-质谱联用(GGMS)

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