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Spectral broadening and red edge excitation effect in liquid and viscous solutions of DMABN

JOURNAL Of LUMINESCENCE 2017年 190卷 344-352页

作者： Tomin, Vladimir I. Dubrovkin, Joseph M. Wlodarkiewicz, Agnieszka Pomeranian Univ Inst Phys PL-76200 Slupsk Poland Western Galilee Coll Comp Dept IL-2421 Akko Israel

Effect of intensity redistribution of two fluorescence bands of N,N'-Dimethylaminobenzonitrile in polar solutions of the different viscosity was studied using selective UV irradiation over the red edge of the main absorption band. The effect being depends on temperature and viscosity, indicated eloquently strong inhomogeneous spectral broadening appearing at the red edge excitation. The conformational broadening exists for electronic transitions in the range of the local excited short wavelength band with weak change of electric dipole moments of the solutes. It was found that the spectral conformational broadening may exists independently on the orientational broadening which is due to the change of solute electric dipole moments in polar media and of thermal environmental fluctuations. When different conformers are excited into upper singlet levels, there is no fast dissipation of excitation energy over different conformational sublevels compared to the charge transfer reaction rates. In this case fluorescence and the charge transfer reaction occur from franck-Condon sublevels with different rates.

关键词： CAN acetonitrile ASIGM the asymmetric double sigmoid function CB the conformational broadening CT the intramolecular charge transfer DMABN N , N′ -dimethylaminobenzonitrile ESIPT the excite state internal proton transfer f C transition - franck-Condon transition IB the inhomogeneous broadening LE the local excited state ME 2 group dimethylamino group OB the orientational broadening PICT the planar intramolecular charge transfer REE spectroscopy the red-edge excitation spectroscopy TICT the twisted intramolecular charge transfer.

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Biogenic fabrication of CuNPs, Cu bioconjugates and in vitro assessment of antimicrobial and antioxidant activity

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IET NANOBIOTECHNOLOGY 2017年第5期11卷 568-575页

作者： Pandit, Raksha Gaikwad, Swapnil Rai, Mahendra SGB Amravati Univ Dept Biotechnol Amravati 444602 Maharashtra India Dr DY Patil Biotechnol & Bioinformat Inst Microbial Divers Res Ctr Pune 411033 Maharashtra India

In the present study, the authors synthesised copper nanoparticles (CuNPs) by using extract of Zingiber officinale (ginger) and later the NPs were bioconjugated with nisin, which shows antimicrobial activity against food spoilage microorganisms. CuNPs and its bioconjugate were characterised by ultraviolet-vis spectroscopy, NP tracking analysis, Zetasizer, transmission electron microscopy analysis, X-ray diffraction and fourier transform infra-red (fTIR) spectroscopy. Zeta potential of CuNPs and its bioconjugate were found to be very stable. They evaluated in vitro efficacy of CuNPs and its bioconjugate against selected food spoilage bacteria: namely, Staphylococcus aureus, Pseudomonas fluorescens, Listeria monocytogenes and fungi including fusarium moniliforme and Aspergillus niger. Antimicrobial activity of CuNPs was found to be maximum against f. moniliforme (18 mm) and the least activity was noted against L. monocytogenes (13 mm). Antioxidant activity of CuNPs and ginger extract was performed by various methods such as total antioxidant capacity reducing power assay, 1-1-diphenyl-2-picryl-hydrazyl free radical scavenging assay and hydrogen peroxide assay. Antioxidant activity of CuNPs was higher as compared with ginger extract. Hence, CuNPs and its bioconjugate can be used against food spoilage microorganisms.

关键词： antibacterial activity biomedical materials copper nanoparticles nanofabrication nanomedicine microorganisms ultraviolet spectra visible spectra electrokinetic effects transmission electron microscopy X-ray diffraction fourier transform infrared spectra free radical reactions food technology biogenic fabrication Cu bioconjugates in vitro assessment antimicrobial activity antioxidant activity copper nanoparticles Zingiber officinale ultraviolet-visible spectroscopy NP tracking analysis Zetasizer transmission electron microscopy X-ray diffraction fourier transform infrared spectroscopy fTIR zeta-potential food spoilage bacteria Staphylococcus aureus Pseudomonas fluorescens Listeria monocytogenes fungi fusarium moniliforme Aspergillus niger f moniliforme L monocytogenes ginger extract total antioxidant capacity power assay 1-1-diphenyl-2-picryl-hydrazyl free radical scavenging assay hydrogen peroxide assay food spoilage microorganisms Cu

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一种基于fPGA的LVDS数据接收方法

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数字技术与应用 2019年第7期37卷 115-116页

作者：王政张宾中国电子科技集团公司第54研究所河北石家庄050081 国网河北省电力有限公司保定供电分公司河北保定071000

LVDS传输方式越来越多的用于高速信息传输中,基于fPGA的LVDS数据接收的应用越来越广泛。本文介绍了一种接收ADS5263芯片输出的LVDS数据的方法,以及在实现过程中需要注意的重点。通过测试,该方法能够适应不同LVDS数据率的需求。

关键词： ADS5263 LVDS f PGA

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functional and Structural Alterations in Temporal Lobe Tumor Patients: Evidence of functional Compensation in the Human Brain

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Chinese Journal of Biomedical Engineering(English Edition) 2018年第3期27卷 109-125页

作者： XUE Li YANG Yu-xuan LING Tao YANG Ya-min QIAN Zhi-yu Department of Biomedical Engineering College of Automation Nanjing University of Aeronautics and Astronautics

Patients with temporal lobe tumor are frequently accompanied by cognitive impairments. This study aims to combine diffusion tensor imaging(DTI) with resting-state functional magnetic resonance image(fMRI) to explore the underlying cognitive alternation and functional reorganization in patients with temporal lobe *** patients with right temporal lobe tumor and seventeen healthy volunteers were recruited in this study. Independent component analysis(ICA) was utilized to divide the whole brain into six sub functional networks, and DTI combined with graph-based topological analysis was used to calculate the structural properties of whole-brain and sub functional networks. Besides, the rich hubs in both patients and healthy controls(HCs)were identified and a further analysis of their internal functional and structural connectivity was also conducted. The E_(global) in self-referential network(SRN) of patients is higher than HCs, while decreased E_(global) of dorsal attention network(DAN) and default mode network(DMN) were found in patients. for the patients, brain regions with increased nodal efficiency(E_(nodal)) were located in the frontal lobe(corresponding to SRN). Six identical hubs were found in two groups. Compared patients with HCs, significant between-group differences in both functional and structural connectivity were observed between right insula(INS.R) and right lenticular nucleus, putamen(PUT.R). The findings provide evidence that impaired cognition are closely related to functional and structural abnormalities and the compensatory roles of frontal lobe were also identified in *** proposed combination of DTI and f MRI promises a widespread utilization in clinical research on the mechanisms of neurological diseases.

关键词： temporal lobe tumor resting state f MRI diffusion tensor imaging compensatory mechanism

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关于加强高校学生office应用能力途径的探讨

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科技创新导报 2019年第19期16卷 220-221页

作者：李欣济宁职业技术学院

off ice软件是学生未来工作中常用的办公软件,加强高校学生off ice应用能力非常重要,为此,需要对高校off ice高级应用课程进行教学改革。首先需要从课程培养目标、教学内容、教学模式以及教学考核方式四个方面创建off ice高级应用课程... 详细信息

off ice软件是学生未来工作中常用的办公软件,加强高校学生off ice应用能力非常重要,为此,需要对高校off ice高级应用课程进行教学改革。首先需要从课程培养目标、教学内容、教学模式以及教学考核方式四个方面创建off ice高级应用课程教学基本架构,再从更改教学大纲,完善教学内容、整合多种教学模式,加强学生应用能力培养、采取“形成性+终结式”考核模式三个方式加强学生off i ce应用能力。

关键词：高校 of f ice 应用能力

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Assessment of Ah receptor transcriptional activity mediated by halogenated dibenzo-p-dioxins and dibenzofurans (PXDD/fs) in human and mouse cell systems

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JOURNAL Of ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2017年第14期52卷 1295-1302页

作者： Organtini, Kari L. Hubbard, Troy D. Perdew, Gary H. Dorman, frank L. Penn State Univ Dept Biochem & Mol Biol 107 Althouse Lab University Pk PA 16802 USA

Polybrominated and mixed bromo/chloro dibenzo-p-dioxins and dibenzofurans (PXDD/fs) are emerging environmental contaminants of concern. Thus far, an understanding of the toxicological behavior of these chemical species and their impact upon human health is incomplete. Here we utilized human and mouse hepatocellular carcinoma cell lines to examine the ability of differentially halogenated PXDD/f congeners to induce aryl hydrocarbon receptor (AHR)-mediated transcriptional activity. Dose-response experiments in reporter cell lines identified varied potencies among differentially halogenated PXDD/f isomers by comparison of EC50 values relative to the prototypical AHR agonist, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Brominated PXDD/f species displayed reduced capacity to activate the mouse AHR, compared to TCDD. Only BrCl3 dibenzo-p-dioxin was found to have a greater relative potency than TCDD to induce human AHR transcriptional activity. Human cells required approximate to 10-29-fold higher ligand concentrations to induce analogous AHR activity, relative to mouse cells. Decreased sensitivity of the human AHR to brominated dibenzofuran congeners directly corresponded to the number of bromine functional groups. Mixtures of these compounds exhibited an additive effect on AHR activation. The data also support the inclusion of mixed halogenated dibenzo-p-dioxins and dibenzofurans into routine environmental screening procedures as well as more thorough toxicological characterization of PXDD/fs.

关键词： Aryl hydrocarbon receptor AHR dibenzofurans dibenzo-p-dioxins mixed halogenated PXDD f

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Anisotropic Behavior of Cosmological Models with Exponential and Hyperbolic Scale factors

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Journal of High Energy Physics, Gravitation and Cosmology 2018年第2期4卷 223-235页

作者： fakhereh Md. Esmaeili School of Physics University of Hyderabad Hyderabad India

In this paper, the cosmological models of the universe are constructed in gravity with choice of the functional in the form ?and . The space-time considered here is Bianchi Type I and the energy momentum tensor is in the form of perfect fluid. Two cosmological models are presented using a power form of exponential function and a hyperbolic form. The energy conditions along with the state finder diagnostic pair have been obtained and analyzed.

关键词： f (R T ) Cosmology Hyperbolic Scale factor Bianchi Type I Hubble Parameter

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Comparisons of field and laboratory estimates of risk of DDTs from contaminated sediments to humans that consume fish in Palos Verdes, California, USA

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SCIENCE Of THE TOTAL ENVIRONMENT 2017年 601卷 1139-1146页

作者： Coffin, Scott Gan, Jay Schlenk, Daniel Univ Calif Riverside Dept Environm Sci Riverside CA 92521 USA

Calculating risk from sea food exposure to persistent organic pollutants continues to be problematic as estimates of exposure from diet require extensive monitoring of fish species and limited assessments of bioavailability from sediments where the contaminants tend to reside. Previous studies in our laboratory utilized a laboratory-based isotope dilution method (IDM) to estimate the bioavailability of DDT [1,1,1-trichloro-2, 2-bis(p-chlorophenyl) ethane] and its metabolites from sediment to biota froma superfund site on the shelf of the Palos Verdes (PVS) Peninsula in California (USA). Using a biota-sediment accumulation factor (BSAf) derived from IDM and biomagnification factors (BMf) calculated from previous studies as well as seafood-consumption data specific to anglers in the PVS area, we estimated cancer and non-cancer risks for anglers and nursing infants representing sensitive groups. Predicted cancer risks from consumption of White croaker (Genyonemus lineatus) to the 50th and 95th percentile to all shore mode anglers were, respectively, 2 x 10(-7) and 7 x 10(-7), which were similar (t)o field studies using fish concentrations of all DDT isomers and their environmental degradates (SDDT) from collected animals. The calculated non-cancer hazard quotient values for the 50th and 95th percentile shore mode anglers consuming White croaker from this study (0.008 and 0.023, respectively) were also of similar magnitude as those obtained from studies based on samples obtained solely from fish. for nursing infants, similar results were also observed. These results indicate that estimates of bioavailability using IDM from sediment could be used accurately to determine risk to SDDT in humans from fish consumption. (C) 2017 Elsevier B. V. All rights reserved.

关键词： DDT 1,1,1-trichloro-2, 2-bis ( p -chloro-phenyl) ethane PVS Palos Verdes Shelf HOCs hydrophobic organic contaminants USEPA United States Environmental Protection Agency IDM Isotope Dilution Method LACSD Los Angeles County Sanitation District ΣDDT total bioavailable DDT BSAf biota-sediment accumulation factor BMf biomagnification factor C f concentration of ΣDDT in White croaker V f lipid fraction in the tissue of White croaker C s ΣDDT concentration in sediment TOC total organic carbon content C p concentration of ΣDDT in polychaete V p lipid fraction in polychaete tissue OEHHA California Environmental Protection Agency Office of Environmental Health Hazard Assessment BLMC breast milk lipid concentration of ΣDDT ADD average daily dose of ΣDDT from fish BMI bw body weight-normalized breast milk ingestion rate during the first year of life CAPCOA California Air Pollution Control Officers Association Ifish sport fish ingestion rate GI gastrointestinal absorption fraction Ef exposure frequency ASf age slope factor CSf cancer slope factor SQO sediment quality objective USACE US Army Corps of Engineers

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Development of High Efficient in vitro Regeneration and Transformation System in Strawberry

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Journal of Northeast Agricultural University(English Edition) 2018年第2期25卷 1-12页

作者： Li Wen-yan Zhou Jing Wei You Wei Chi-zhang South Asian Tropical Agricultural Science Research Institute of Guangxi Longzhou 532415 Guangxi China

In this paper, several factors that affect the efficiency of in vitro adventitious bud regeneration and Agrobacterium tumefaciens-mediated transformation of f. vesca were studied. The results showed that f. vesca seeds germination rate was the highest while seeds were cultured in water, and the germination rate was the lowest while seeds were cultured on MS medium supplemented with hormone; the germination rates that seeds cultured on two and three layers filter paper were higher than that seeds cultured on four and five layers filter paper. In vitro adventitious regeneration efficiency was affected by different explants types. The significant difference was existed between petioles and leaves. When using the same type explants, in vitro adventitious buds regeneration rate and the average number of buds per explant between Ruegen （RE） and Yellow Wonder （YW） had no significant difference. RE to Agrobacterium tumefaciens was more sensitive than YW. Using seedling leaves of RE and YW as materials, an efficient Agrobacterium-mediated transformation system was developed. In this system, the concentration of bacteria was OD600=0.5, the explants were immersed in bacteria broth for 9 min, the co-cultured time was 2 days, and had no pre-cultured time. The percentage of explants with resistant buds of RE and YW was compared. The putative transformed plants were confirmed by PCR.

关键词： f vesca in vitro regeneration Agrobacterium genetic transformation

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Dynamics of Bianchi I Universe in Extended Gravity with Scale factors

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Journal of High Energy Physics, Gravitation and Cosmology 2018年第4期4卷 716-730页

作者： fakhereh MD. Esmaeili School of Physics University of Hyderabad Hyderabad India

In this paper, the dynamical behavior of an anisotropic universe in an extended gravity e.g. the f (R,T ) theory of gravity is studied. We use f (R,T ) = R + 2μT , where R is the Ricci scalar, T is the trace of energy-momentum tensor and μ is a constant. Two cosmological models are constructed using the power law expansion and hybrid law cosmology in Bianchi type I universe, where the matter field is considered to be a perfect fluid. It is found that in both the cases the anisotropic behavior is in agreement with the observational results. The state finder diagnostic pair and energy conditions are also calculated and analyzed.

关键词： f (R T ) Gravity Bianchi Type I Perfect fluid Anisotropic Universe SEC

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