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Radiation-induced in vitro mutagenesis system for salt tolerance and other agronomic characters in sugarcane(Saccharum officinarum L.)

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The Crop Journal 2015年第1期3卷 46-56页

作者： Ashok A.Nikam Rachayya M. Devarumath Akash Ahuja Harinath Babu Mahadeo g.Shitole Penna Suprasanna Tissue Culture Section Vasantdada Sugar InstituteManjari (Bk) Pune 412307 India Molecular Biology and genetic Engineering Division Vasantdada Sugar InstituteManjari (Bk) Pune 412307 India Department of Botany Pune University Plant Stress Physiology & Biotechnology Section Nuclear Agriculture & Biotechnology Division Bhabha Atomic Research Centre

gamma ray-induced in vitro mutagenesis and selection for salt(NaC l) tolerance were investigated in sugarcane(Saccharum officinarum L.). Embryogenic callus cultures were irradiated(10 to 80 gy) and subjected to in vitro selection by exposure of irradiated callus to NaC l(0, 50, 100,150, 200, and 250 mmol L-1). Increasing NaC l concentrations resulted in growth reduction and increased membrane damage. Salt-selected callus lines were characterized by the accumulation of proline, glycine betaine, and Na+and K+concentration. Higher accumulation of proline and glycine betaine was observed in NaC l stressed callus irradiated at 20 gy. Na+concentration increased and K+concentration decreased with increasing salt level. Irradiated callus showed50–60% regeneration under NaC l stress, and in vitro-regenerated plants were acclimatized in the greenhouse, with 80–85% survival. A total of 138 irradiated and salt-selected selections were grown to maturity and their agronomic performance was evaluated under normal and saline conditions. Of these, 18 mutant clones were characterized for different agro-morphological characters and some of the mutant clones exhibited improved sugar yield with increased Brix%,number of millable canes, and yield. The result suggest that radiation-induced mutagenesis offers an effective way to enhance genetic variation in sugarcane.

关键词： gamma-rays Mutagenesis Embryogenic callus Saccharum officinarum L Salt tolerance

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Solar Activity and the Climate of Prebaikalia

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空间科学学报 2005年第5期25卷 474-477页

作者： V.A.Kovalenko g.A.Zherebtsov S.I.Molodykh Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia

This paper presents convincing evidence for the reality of manifestations of solar variability in climate characteristics of the Prebaikalia. A numerical estimate is obtained of this influence on ground air temperature. It is shown that the main meaningful variations in air temperature in the region for the period1881-1960 were caused by solar activity. Since the 1960s till the present, with the influence of solar variability continuing, a clear-cut influence of another factor has been observed, the role of which has been steadily increasing, and in the hst decade it has now exceeded the contribution of solar variability. Research results on the variations in hydrological characteristics of Lake Baikal and the Angara river and their connection with solar activity are presented. It is shown that these characteristics are closely correlated with the duration of solar cycles.

关键词：太阳活动气候变化大气 gAT

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Electrical and mechanical studies on ferroelectric lithium rubidium sulphate crystals

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Journal of Advanced Dielectrics 2018年第3期8卷 17-27页

作者： F.A.Najar g.B.Vakil B.Want Department of Physics University of Kashmir Srinagar 190006India Solid State Research Laboratory Department of Physics University of KashmirSrinagar 190006India

Slow evaporation method was used to grow single crystals of lithium rubidium sulphate with high *** crystal X-ray diffraction analysis shows that at room temperature,the crystal belongs to a monoclinic system with the space group P21/*** physical parameters like plasma energy,Penn gap,Fermi energy and electronic polarizability have been evaluated for the grown *** relation between electronic polarizability and diamagnetic susceptibility for the crystal has been established on the basis of Kirkwood’s semiempirical *** ac conductivity and dielectric behavior of the grown crystal were systemically investigated as a function of frequency and *** title compound obeys Jonscher’s power law relations:ð(ω)=σo+Aω^(s),with exponent sge polarons take part in conduction process,and at low temperature,both the band and hopping mechanisms are responsible for *** impedance and modulus studies,it is observed that only one conduction relaxation is observed in the crystal at low *** activation energy of the dielectric relaxation(0.41 eV)and that of the conduction(Econd¼0:43 eV)are in agreement,as a result,there is no difference among the conduction and relaxation species at high *** scanning calorimetric analysis of the crystal shows three endothermic peaks at 166℃,185℃,and 202℃,from which various thermodynamic parameters such asΔH,ΔS andΔC_(p) have been *** Vickers hardness test,we have determined the mechanical strength,and other parameters which include fracture toughness,brittleness index,yield strength,and stiffness constant for the crystal.

关键词： Slow evaporation monoclinic conductivity impedance activation energy

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Effects of Composted and Thermally Dried Sewage Sludges on Soil and Soil Humic Acid Properties

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Pedosphere 2009年第3期19卷 281-291页

作者： J. M. FERNNDEZ N. SENESI C. PLAZA g. BRUNETTI A. POLO Centro de Ciencias Medioambientales Consejo Superior de Investigaciones Científicas Serrano 115 dpdo. 28006 Madrid(Spain) Dipartimento di Biología e Chimica Agroforestale e Ambientale University of Bari Via Amendola 165/A 70126 Bari(Italy)

The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid conditions. Humic acids (HAs) isolated by conventional procedures from CS, TS, and unamended (SO) and sludge amended soils were analysed for elemental (C, H, N, S and O) and acidic functional groups (carboxylic and phenolic) and by ultraviolet-visible, Fourier transform infrared and fluorescence spectroscopies. With respect to CS, TS had similar pH and total P and K contents, larger dry matter, total organic C, total N and C/N ratio and smaller ash content and electrical conductivity. Amendment with both CS and TS induced a number of modifications in soil properties, including an increase of pH, electrical conductivity, total organic C, total N, and available P. The CS-HA had greater O, total acidity, carboxyl, and phenolic OH group contents and smaller C and H contents than TS-HA. The CS-HA and TS-HA had larger N and S contents, smaller C, O and acidic functional group contents, and lower aromatic polycondensation and humification degrees than SO-HA. Amended soil-HAs showed C, H, N and S contents larger than SO-HA, suggesting that sludge HAs were partially incorporated into soil HAs. These effects were more evident with increasing number of sludge applications.

关键词： elemental composition fluorescence spectroscopy Fourier transform infrared spectroscopy functional group composition

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Reflection and transmission properties of a finite-length electron plasma grating

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Matter and Radiation at Extremes 2022年第5期7卷 17-28页

作者： g.Lehmann K.H.Spatschek Institut für Theoretische Physik I Heinrich-Heine-Universität DüsseldorfD-40225 DüsseldorfGermany

Considered here is a plasma grating generated by two counterpropagating short laser pulses. Because of the shortness of the laser pulses, theplasma dynamics are determined by only electrons, which respond to the ponderomotive pressure generated by the interacting laser *** electron grating cannot exist for longer than the inverse ion plasma frequency, and so because of the limited time of the ponderomotivepressure, both the life time and spatial extent of an electron grating are finite. When one of the short laser pulses is circularly polarized(propagating in the x direction with electric field vectors in the yz plane) and the other is linearly y-polarized, the electron grating is producedby the y components. Meanwhile, the z component is partially reflected, and only a fraction of it is transmitted. Thus, the finite plasmagrating can either alter the polarization of the yz-polarized pulse or act as a pulse splitter. The present paper is focused on the reflection andtransmission rates. The action of the density grating on the z component cannot be explained by the Bloch wave theory for infinite crystals,and instead a theory is developed based on four-wave mixing, which explains the transmission and reflection of the z component wheninteracting with a grating of finite extent.

关键词： polarization finite polarized

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Correlations between structure,microstructure,density and dielectric properties of the lead-free ferroelectrics Bi_(0.5)(Na,K)_(0.5)TiO_(3)

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Journal of Advanced Dielectrics 2015年第4期5卷 10-15页

作者： K.Anjali T.g.Ajithkumar P.A.Joy Physical and Materials Chemistry Division Central NMR Facility Academy of Scientific and Innovative Research(AcSIR)CSIR-National Chemical Laboratory(CSIR-NCL)Pune 411008 India

Solid solutions of the lead-free ferroelectric oxides Bi_(0.5)Na_(0.5)TiO_(3)(BNT)and Bi_(0.5)Na_(0.5)TiO_(3)(BKT),represented as(1-x)BNT-xBKT,are studied for very close compositions in the range0≤x≤0.36 to understand the correlation between the structure and the *** are varied in steps of △x=0.02 in the range0≤x≤0.1 and0.2≤x≤0.36 and△x=0.01 in the range 0.1≤x≤0.2,to precisely locate the structural transition as well as the morphotropic phase boundary(MPB)region and the compositional region of best *** refinement analysis of the powder X-ray diffraction patterns showed monoclinic phase up to x=0.17 and a mixture of monoclinic and tetragonal phases for x>***,the density and the dielectric constant showed linear variation up to x=0.17 and a large increase above this composition,showing maximum values in the compositional range 0.22≤x≤0.26,corresponding to the MPB *** features also showed corresponding changes,indicating close relationship between the structure,microstructure and properties of the different compositions.

关键词： Bismuth sodium potassium titanate Bi_(0.5)N_(0.5-x)KxTiO_(3) lead-free ferroelectrics morphotropic phase boundary structure-property correlations

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On the volatility of daily stock returns of Total Nigeria Plc: evidence from gARCH models, value-at-risk and backtesting

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Financial Innovation 2020年第1期6卷 347-371页

作者： Ngozi g.Emenogu Monday Osagie Adenomon Nwaze Obini Nweze Department of Statistics Federal PolytechnicBidaNiger StateNigeria Department of Statistics Nasarawa State Univ ersityKeffiNasarawa StateNigeria

This study investigates the volatility in daily stock returns for Total Nigeria Plc using nine variants of gARCH models:sgARCH,girgARCH,egARCH,igARCH,agARCH,TgARCH,NgARCH,NAgARCH,and AVgARCH along with value at risk estimation and *** use daily data for Total Nigeria Plc returns for the period January 2,2001 to May 8,2017,and conclude that egARCH and sgARCH perform better for normal innovations while NgARCH performs better for student t *** investigation of the volatility,VaR,and backtesting of the daily stock price of Total Nigeria Plc is important as most previous studies covering the Nigerian stock market have not paid much attention to the application of backtesting as a primary *** found from the results of the estimations that the persistence of the gARCH models are stable except for few cases for which igARCH and egARCH were ***,for student t innovation,the sgARCH and girgARCH models failed to converge;the mean reverting number of days for returns differed from model to *** the analysis of VaR and its backtesting,this study recommends shareholders and investors continue their business with Total Nigeria Plc because possible losses may be overcome in the future by improvements in stock ***,risk was reflected by significant up and down movement in the stock price at a 99%confidence level,suggesting that high risk brings a high return.

关键词： Volatility Returns Stocks Total petroleum Akaike information criterion(AIC) gARCH Value-at-risk(VaR) Backtesting

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Accommodating the bacterial decoding release factor as an alien protein among the RNAs at the active site of the ribosome

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Cell Research 2007年第7期17卷 591-607页

作者： Elizabeth S Poole David J Young Marjan E Askarian-Amiri Debbie-Jane g Scarlett Warren P Tate Department of Biochemistry University of OtagoP.O.Box 56 DunedinNew Zealand

The decoding release factor (RF) triggers termination of protein synthesis by functionally mimicking a tRNA to spanthe decoding centre and the peptidyl transferase centre (PTC) of the ribosome. Structurally, it must fit into a site craftedfor a tRNA and surrounded by five other RNAs, namely the adjacent peptidyl tRNA carrying the completed polypeptide,the mRNA and the three rRNAs. This is achieved by extending a structural domain from the body of the protein thatresults in a critical conformational change allowing it to contact the PTC. A structural model of the bacterial terminationcomplex with the accommodated RF shows that it makes close contact with the first, second and third bases of the stopcodon in the mRNA with two separate loops of structure: the anticodon loop and the loop at the tip of helix α5. Theanticodon loop also makes contact with the base following the stop codon that is known to strongly influence termina-tion efficiency. It confirms the close contact of domain 3 of the protein with the key RNA structures of the PTC. ThemRNA signal for termination includes sequences upstream as well as downstream of the stop codon, and this may reflectstructural restrictions for specific combinations of tRNA and RF to be bound onto the ribosome together. An unbiasedSELEX approach has been investigated as a tool to identify potential rRNA-binding contacts of the bacterial RF in itsdifferent binding conformations within the active centre of the ribosome.

关键词： release factor protein synthesis termination tRNA functional mimicry molecular mimicry SELEX ribosome

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c-Fos overexpression increases the proliferation of human hepatocytes by stabilizing nuclear Cyclin D1

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World Journal of gastroenterology 2008年第41期14卷 6339-6346页

作者： Meryem güller Kahina Toualbi-Abed Agnès Legrand Laurence Michel Alain Mauviel Dominique Bernuau Fanny Daniel Institut National de laSanté et de la Recherche Médicale U697 Hpital Saint-Louis Institut National de la Santé et de la RechercheMédicale U591 Faculté de Médecine Necker Institut National de la Santé et de la RechercheMédicale U773 Centre de Recherche Bichat Beaujon CRB3and Université Paris 7 Denis Diderot site Bichat

AIM： To investigate the effect of stable c-Fos over- expression on immortalized human hepatocyte （IHH） proliferation. METHODS： IHHs stably transfected with c-Fos （IHH- Fos） or an empty vector （IHH-C） were grown in me- dium supplemented with 1% serum or stimulated with 10% serum. Cell proliferation was assessed by cell counts, 3H-thymidine uptake and flow cytometry analyses. The levels of cell cycle regulatory proteins （Cyclin DI, E, A） cyclin dependent kinases （cdk） cdk2, cdk4, cdk6, and their inhibitors p15, p16, p21, p27, total and phosphorylated gSK-3β and epidermal growth factor receptor （EgF-R） were assayed by Western blotting. Analysis of O/c/in D1 mRNA levels was performed by reverse transcription-polymerase chain reaction and real-time polymerase chain reaction （PCR） analysis. Stability of Cyclin DI was studied by cycloheximide blockade experiments. RESULTS： Stable c-Fos overexpression increased cell proliferation under low serum conditions and resulted in a two-fold increase in [3H]-thymidine incorpora- tion following serum addition. Cell cycle analysis by flow cytometry showed that c-Fos accelerated the cell cycle kinetics. Following serum stimulation, Cyclin D1 was more abundantly expressed in c-Fos overexpress- ing cells. Cyclin D1 accumulation did not result from increased transcriptional activation, but from nuclear stabilization. Overexpression of c-Fos correlated with higher nuclear levels of inactive phosphorylated gSK- 3β, a kinase involved in Cyclin D1 degradation and higher levels of EgF-R mRNA, and EgF-R protein com- pared to IHH-C both in serum starved, and in serum stimulated cells. Abrogation of EgF-R signalling in IHH- Fos by treatment with Ag1478, a specific EgF-R tyro- sine kinase inhibitor, prevented the phosphorylation of gSK-3β induced by serum stimulation and decreased Cyclin D1 stability in the nucleus. CONCLUSION： Our results clearly indicate a positive role for c-Fos in cell cycle regulation in hepatocytes. Importantly, we delineate

关键词： c-Fos Cyclin DI gSK-3 Cell growth, Cell cycle Hepatoma Epidermal growth factor

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Mitral peak early diastolic filling velocity to deceleration time ratio as a predictor of prognosis in patients with chronic heart failure and preserved or reduced ejection fraction

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Journal of geriatric Cardiology 2015年第4期12卷 346-352页

作者： Flora Pirozzi AntoneUa Paglia Laura Sasso Pasquale Abete Angelo Carlomagno Carlo g Tocchetti Domenico Bonaduce Mario Petretta Department of Translational Medical Sciences Section of Internal Medicine Federico Ⅱ University Naples ltaly

Objective Doppler derived mitral peak early diastolic filling velocity to deceleration time ratio （E/DT） has been proposed as parameter for predicting prognosis in general population. This study prospectively investigates the incremental prognostic value of E/DT over clinical, conven- tional eehocardiographic and mitral-Doppler variables in patients hospitalized for decompensated heart failure （HF）. Methods We analyzed 95 HF patients （mean age 64.8 ± 12.2 years） hospitalized at our institution from January 2010 to March 2012. The primary end-point was cardiac death or hospitalization, whichever occurred first. Cox regression analysis was performed to identify significant predictors of outcomes. Results During follow-up （median 37.7 months） 13 patients died and 44 were hospitalized for a cardiac event. At univariable analysis, New York Heart Association （NYHA） functional class, furosemide dosage, lateral tricuspidal annular plane systolic excursion, deceleration lime and E/DT were predictive of outcome. At multivariable analysis, E/DT was the only predictor of prognosis （hazard ratio = 1.02, P = 0.018）, giving incremental prognostic information to clinical and other echocardio-graphic measures （global chi-square from 15.4 to 25.2; P = 0.032）. Conclusions FJDT gives independent and incremental prognostic information in HF patients.

关键词： Echocardiographic evaluation Left venlricular function Risk stratification

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