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Radiative transition

Radiative transition

Post-Translational Derepression of Invertase Activity in Source Leaves via Down-Regulation of Invertase Inhibitor Expression Is Part of the Plant Defense Response

作者： nora Brambilla Antonio Vairo

＜正＞4.2.1 Introduction Radiative transitions historically have played important roles in establishing new quarkonium *** today,these simple processes are still of considerable exper- imental and theoretical *** the theoretical side,the photon serves as a clean probe to internal structrue of quarkonium,therefore a thorough understanding of these

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Molecular Plant 2010年第6期3卷 1037-1048页

作者： Katharina B. Bonfig Andrea Gabler Uwe K. Simon nora Luschin-Ebengreuth Martina Hatz Susanne Berger Naseem Muhammad Jurgen Zeier Alok K. Sinha Thomas Roitsch Julius-von-Sachs-Institut fuer Biowissenschaften Lehrstuhl for Pharmazeutische Biologie Universitaet Wuerzburg Julius-von-Sachs-Platz 2 97082 Wuerzburg Germany Institute of Plant Sciences Department of Plant Physiology University of Graz 8010 Graz Austria Zentrum for rnedizinische Grundlagenforschung (ZMF) Medizinische Universitat Graz Stiftingtalstraβe 24 A-8010 Graz Department of Biology Plant Biology Section University of Fribourg Route Albert Gockel 3 CH-1700 Fribourg Switzerland National Institute for Plant Genome Research Aruna Asaf Ali Road New Delhi 110067 India

There is increasing evidence that pathogens do not only elicit direct defense responses, but also cause pronounced changes in primary carbohydrate metabolism. Cell-wall-bound invertases belong to the key regulators of carbohydrate partitioning and source-sink relations. Whereas studies have focused so far only on the transcriptional induction of invertase genes in response to pathogen infection, the role of post-translational regulation of invertase activity has been neglected and was the focus of the present study. Expression analyses revealed that the high mRNA level of one out of three proteinaceous invertase inhibitors in source leaves of Arabidopsis thaliana is strongly repressed upon infection by a virulent strain of Pseudomonas syringae pv. tomato DC3000. This repression is paralleled by a decrease in invertase inhibitor activity. The physiological role of this regulatory mechanism is revealed by the finding that in situ invertase activity was detectable only upon infection by P. syringae. In contrast, a high invertase activity could be measured in vitro in crude and cell wall extracts prepared from both infected and non-infected leaves. The discrepancy between the in situ and in vitro invertase activity of control leaves and the high in situ invertase activity in infected leaves can be explained by the pathogen-dependent repression of invertase inhibitor expression and a concomitant reduction in invertase inhibitor activity. The functional importance of the release of invertase from post-translational inhibition for the defense response was substantiated by the application of the competitive chemical invertase inhibitor acarbose. Posttranslational inhibition of extracellular invertase activity by infiltration of acarbose in leaves was shown to increase the susceptibility to P. syringae. The impact of invertase inhibition on spatial and temporal dynamics of the repression of photosynthesis and promotion of bacterial growth during pathogen infection supports a

关键词： Acarbose Arabidopsis defense responses invertase inhibitor protein invertase plant-microbe interactions Pseudomonas syringae.

Toxicity and removal of phenanthrene,fluoranthene and pyrene by two Navicula species,***（a commercial species） and ***（a local isolate）

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Toxicity and removal of phenanthrene,fluoranthene and pyrene...

Synthesis and Piezoelectric Properties of Pb0.98Sm0.02[(Zry,Ti1–y)0.98(Fe1/23+,Nb1/25+)0.02]O3Ceramics

中国藻类学会第八次会员大会暨第十六次学术讨论会

作者： nora Fung-yee Tam Department of Biology and Chemistry City University of Hong KongTat Chee AvenueKowloonHong Kong SARChina

＜正＞The present study showed that the tolerance of two Navicula diatoms,a local isolate {Navicula sp.) and a commercial species {Navicula incerta),to three polycyclic aromatic hydrocarbons（PAHs）,phenanthrene（PHE）,fluoranthene（FLU） and pyrene（PYR）, was PAH- and *** and PYR exhibited comparable median effect concentration（EC50） values（7.39-9.30 mg/L） but were remarkably higher than FLU （0.41-5.16 mg/L）,suggesting that FLU was more toxic to Navicula *** local isolate was more sensitive to FLU toxicity than the commercial species and the EC50 of the local isolate was very low（0.41 mg/L）.Both species were capable to remove PAHs, the efficiency was also PAH-dependent and followed the declining order of PHE＞FLU＞*** the end of 7-days treatment,the biodegradation percentages of PHE,FLU and PYR（calculated based on the difference between the amount of PAH added and the summation of the amount remained in medium,accumulated in cells and abiotic loss） by *** were 65.9%,57.0%and 34.7%,respectively,while their respective values by the local isolate were 74.9%,57.7%and 26.1%.These results indicated that PYR was not only the most difficult PAH to be removed but was also most resistant to biodegradation by these two diatom species than the other two *** removal and biodegradation percentages were affected by the initial concentration of PAHs in the *** FLU and PYR remained in the medium,as well as accumulated in cells,at 5.0 mg/L treatment than at the two lower levels,0.5 and 1.0 mg/L,while the biodegradation percentages of all three PAHs at 5.0 mg/L treatment were also *** only PAH-dependent,the PAH tolerance and removal were also *** local isolate did not exhibit a higher tolerance to PAHs and it did not achieve better removal and biodegradation than the commercial species.

关键词： Biodegradation diatom EC50 microalgae Navicula Polycyclic aromatic hydrocarbons(PAHs)

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Materials Sciences and Applications 2012年第1期3卷 50-58页

作者： Fares Kahoul Louanes Hamzioui nora Abdessalem Ahmed Boutarfaia 不详

The structural and electrical properties of Pb0.98Sm0.02[(Zry,Ti1–y)0.98( Fe1/23+,Nb1/25+)0.02]O3 ceramics system with the composition near the morphotropic phase boundary were investigated as a function of the Zr/Ti ratio by X-ray diffraction (XRD). Studies were performed on the samples prepared by solid state reaction for y = 0.47, 0.49, 051, 0.53, 0.55 and 0.57. Combined with piezoelectric properties results, it was consistently shown that an MPB exists between y = 0.51 and y = 0.55 in this system. When y 0.55, the rhombohedral phase dominates. Lattice parameters of the tetragonal phase and rhombohedral phase were found to vary with chemical composition. The average particle size ranged from 17.18 to 26.05 nm. The dielectric (ε = 1076), tan δ = 0.013 and piezoelectric properties (d31 = 122 pC/N, kp = 0.631 and Qm = 462) obtained were maximum at y = 0.55 which could be suitable for possible electromechanical and energy harvesting applications.

关键词： X-Ray Methods Co-Existence of Phase Piezoelectric Properties Dielectric Properties

Predictive Study of Velocimetry in the Coronary Artery after Iodinated Contrast Agent Injection

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2017年第1期6卷 93-104页

作者： nora Hocine Julie Colnot Helene Masset Didier Franck Institut de Radioprotection et de Surete Nucleaire(IRSN) Fontenay-aux-RosesFrance Centre Hospitalier Universitaire Henri Mondor CreteilFrance

This study aims to determine the retention time of iodinated contrast agents (ICA) in the coronary artery. The mechanical aspect of ICA displacement was studied in order to better understand the effect of these products on the inner wall of the artery of patients with coronary artery stenosis, undergoing repeated imaging examinations with iodinated contrast agents. ICA flow, ICA and blood flow in the artery were modelled. The fluid was regarded to be viscous, incompressible and Newtonian. Blood flow was presumed to be unidirectional, laminar and unstationary. Iodine flow velocity and retention time were calculated using the Runge-Kutta 4th order method programmed in C++ and MatLab R2013a language. The results showed that for coronary artery CT-scans, ICA retention time is 1 minute 40 seconds and for coronary arteriography it is between 2.41 and 3.61 seconds. The values calculated were compared to theoretical values and to clinical observations. The results enabled us to validate our model.

关键词： Coronary Artery Iodinated Contrast Agent Blood Flow

Evaluation of Urinary Hepcidin as a Marker for the Early Diagnosis of Iron Deficiency Anemia in Children

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Open Journal of Pediatrics 2020年第2期10卷 347-355页

作者： Somaia Moussa Asmaa Abd-Alwakeel Ibrahim nora Mohamed Ahmed El-Mansura Ad Daqahliyah Egypt Pediatrics Faculty of Medicine for Girls Al-Azhar University Al Behira Egypt Biochemistry Faculty of Medicine for Girls Al-Azhar University Cairo Egypt

Background: Iron deficiency is an essential element, because nearly all living organism urine hepcidin levels could potentially be used in the determination of iron requirements and be an accurate indicator of physiological IDA. Aim: The present study aimed to evaluate the role of urinary hepcidin as an early diagnostic marker of iron deficiency anemia in children. Methods: This study included 45 children. Their age ranged from 6 to 16 years with hemoglobin levels ≤ 11.5 gm/dL and ferritin levels ≤ 20 ng/mL. The diagnostic performance of urinary hepcidin was estimated by analyzing the receiver operating characteristic curve. Diagnostic cut-off point with a high predictive value for iron deficiency was selected. Results: This study showed no statistically significant difference between the two studied groups regarding to demographic data. There were decrease in serum iron, ferritin, hemoglobin and Red blood cells (RBCs) indices in patient than the control group. There was non-significant decrease in urinary hepcidin in the study group compared to control group. The sensitivity and specificity of urinary hepcidin in diagnoses of iron deficiency anemia was 57.8 and 62.2 respectively with positive predictive value (63.3) in our study. There was positive correlation between urinary hepcidin and mean corpuscular volume (MCV), (r = 0.221), (p = 0.036), with the cut of value Conclusion: We concluded that the decreas

关键词： Hepcidin Iron Anemia Pediatrics

Study of Dielectric and Piezoelectric Properties in the Ternary System Pb0.98Ca0.02[{(Zr0.52Ti0.48)0.98(Cr3+0.5, Ta5+0.5)0.02}1–zPz]O3Doping Effects

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Materials Sciences and Applications 2012年第1期3卷 41-49页

作者： Hamzioui Louanes Kahoul Fares Abdessalem nora Boutarfaia Ahmed 不详

The effects of P2O5 oxide on microstructure, dielectric and piezoelectric properties of Pb0.98Ca0.02[{(Zr0.52Ti0.48)0.98( Cr3+1/2,Ta5+1/2)0.02}1–zPz]O3 ternary ceramics were investigated. Specimens with various contents of P2O5 from 0 to 12 wt. % were prepared by a conventional oxide mixing technique. The effect of P2O5 doping with regard to the development of the crystalline phase, density, microstructure, dielectric, ferroelectric and piezoelectric characteristics has been investigated. It has been found that the sintering temperature of piezoelectric Pb0.98Ca0.02[{(Zr0.52Ti0.48)0.98(Cr3+1/2,Ta5+1/2)0.02}1–zPz]O3 can be reduced by phosphorus addition without compromising the dielectric properties. A sintered density of 94 % of the theoretical density was obtained for 4 wt. % P2O5 addition after sintering at 1050°C for 4 h. Ceramics sintered at 1050°C with 4 wt. % P2O5 achieve excellent properties, which are as follows: kp = 0.73, ρ = 0.09 × 10+4 (Ω. cm), εr = 18800, tanδ = 0.0094 and Tc = 390°C.

关键词： PZT Piezoelectricity Electronic Materials Dielectric Properties Methods Physico-Chemical of Analysis

Enhanced Face Detection Technique Based on Color Correction Approach and SMQT Features

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Journal of Software Engineering and Applications 2013年第10期6卷 519-525页

作者： Mohamed A. El-Sayed nora G. Ahmed Department of Mathematics Faculty of Science Fayoum University Al Fayoum Egypt Department of Mathematics Faculty of Science Sohag University Sohag Egypt

Face detection is considered as a challenging problem in the field of image analysis and computer vision. There are many researches in this area, but because of its importance, it needs to be further developed. Successive Mean Quantization Transform (SMQT) for illumination and sensor insensitive operation and Sparse Network of Winnow (SNoW) to speed up the original classifier based face detection technique presented such a good result. In this paper we use the Mean of Medians of CbCr (MMCbCr) color correction approach to enhance the combined SMQT features and SNoW classifier face detection technique. The proposed technique is applied on color images gathered from various sources such as Internet, and Georgia Database. Experimental results show that the face detection performance of the proposed method is more effective and accurate compared to SFSC method.

关键词： Face Detection Color Correction MMCbCr SMQT Features

A Comparative Study of the Typhidot (Dot-EIA) versus Widal Test in Diagnosis of Typhoid Fever among Egyptian Patients

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Open Journal of Gastroenterology 2019年第6期9卷 91-98页

作者： Rasha I. Salama nora M. Said Tropical Medicine Department Faculty of Medicine Zagazig University Zagazig Egypt Clinical Pathology Department Faculty of Medicine Zagazig University Zagazig Egypt

Background and Study Aim: Typhoid (Enteric) fever is a systemic infection caused by Salmonella Typhi and Salmonella Paratyphi. It is endemic in the developing countries including Egypt. Different diagnostic tools can achieve diagnosis and include cultures from the blood, stool, bone marrow, rarely urine for isolation of the organism. Antibody detection by Widal test and relatively recent typhoid are also used. The current study aimed at comparing the most commonly used antibody detection Widal test with the rapid antibody detection typhidot for diagnosis of typhoid fever among Egyptian adults. Patients and Methods: The study included 140 patients who are presented with picture suggestive of typhoid fever. Confirmed cases after the blood culture were included in the final analysis. Widal and typhidot tests were performed in all patients and were compared for sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy. Results: 45 patients out of 140 were diagnosed as typhoid fever by blood culture. Out of them, Widal test was positive in 39 patients with sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of 86.7%, 89.5%, 79.5%, 93.4% and 88.5% respectively. Typhidot test was positive in 42 patients with sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of 93.3%, 90.6%, 82.3%, 96.6%, and 91.4% respectively (P = 0.00). Conclusions: Typhidot test is reliable, simple highly sensitive and specific test in diagnosing typhoid fever when compared with Widal test.

关键词： Typhidot Widal Test Typhoid Fever