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Effect of NO_3^--N Enrichment on seawater stress Tolerance of Jerusalem Artichoke (Helianthus tuberosus)

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Pedosphere 2008年第1期18卷 113-123页

作者： s.k.MEHTA College of Resources and Environmental sciences Nanjing Agricultural University

A hydroponic experiment with six treatments, i.e., 0% seawater （control）, 10% seawater, 25% seawater, 0% seawater ＋ N （7.5 mmol L-1 NaNO3）, 10% seawater ＋ N （7.5 mmol L-1 NaO3）, and 25% seawater ＋ N （7.5 mmol L-1 NaNO3）, was carried out to study the effect of nitrogen addition on the growth and physiological and biochemical characteristics of Jerusalem artichoke （Helianthus tuberosus） seedlings under seawater stress. The 10% seawater stress treatment had the least effect on plant growth while at 25% seawater growth was significantly inhibited. The malondialdehyde content and electrolyte leakage in leaves under 10% seawater were similar to those of the control, but significantly higher under the 25% seawater stress. The activities of superoxide dismutase, peroxidase and catalase in the leaves increased concomitantly with increasing seawater concentration and time. Proline and soluble-sugars in the leaves and Na^＋, k^＋, and Cl- contents in shoots and roots increased significantly with the concentration of seawater increasing. Nitrogen addition resulted in increasing fresh and dry weights of shoots and roots compared with seawater treatment without N. Nitrogen supplementation also significantly enhanced the activities of antioxidant enzymes in leaves. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves and k^＋ and total-N in the aerial parts and roots of H. tuberosus, but it resulted in declined concentrations of Na^＋ and Cl- in the aerial parts and roots. Nitrogen addition ameliorated the toxicity of seawater by improving the antioxidative enzymes, accumulating of proiine and soluble-sugars, and altering the distribution of inorganic ions in H. tuberosus.

关键词： Helianthus tuberosus ions distributions malondialdehyde nitrate seawater stress

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

The Fibered Isomorphism Conjecture for Complex Manifolds

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Acta Mathematica sinica,English series 2007年第4期23卷 639-658页

作者： s.k.ROUsHON school of Mathematics Tata InstituteHomi Bhabha RoadMumbai 400 005India

In this paper we show that the Fibered Isomorphism Conjecture of Farrell and Jones, corresponding to the stable topological pseudoisotopy functor, is true for the fundamental groups of a class of complex manifolds. A consequence of this result is that the Whitehead group, reduced projective class groups and the negative k-groups of the fundamental groups of these manifolds vanish whenever the fundamental group is torsion free. We also prove the same results for a class of real manifolds including a large class of 3-manifolds which has a finite sheeted cover fibering over the circle.

关键词： Complex projective variety Complex surfaces Whitehead group Fibered isomorphism conjecture Negative k-groups

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano sergei A.kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Combustion synthesis and luminescence characteristic of rare earth activated LiCaBO_3

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Journal of Rare Earths 2012年第10期30卷 1005-1008页

作者： N.s. Bajaj s.k. Omanwar Department of Physics SGB Amravati University Amravati-444602 (M.S.)

Lithium calcium borate （LiCaBO3） polycrystalline thermoluminescence （TL） phosphor doped with rare earth （Tb3＋ and Dy3＋） elements was synthesized by novel solution combustion synthesis. The reaction produced very stable crystalline LiCaBO3：D（D=Tb3＋ and Dy3＋） phosphors. These rare earth doped phosphors material showed maximum TL sensitivity with favorable glow curve shape. TL glow curve of X-ray irradiated that LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ samples showed two major well-separated glow peaks. The TL sensitivity of these phosphors to X-ray radiation was comparable with that of TLD-100（Harshaw）. Photoluminescence spectra of LiCaBO3：Tb3＋ and LiCaBO3：Dy3＋ showed the characteristic Tb3＋ and Dy3＋ peaks respectively. TL response to X-ray radiation dose was linear up to 25 Gy.

关键词： luminescence LiCaBO3 combustion synthesis rare earths kinetics

Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method

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Chinese Physics B 2019年第4期28卷 342-348页

作者： s Mourad J El Ghoul k Omri k khirouni Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE) Faculty of Sciences in Gabes Gabes University Imam Mohammad Ibn saud Islamic University (IMsIU) College of Sciences Department of Physics

Pure ZnO and indium-doped ZnO(In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In^(3+) ions at the Zn^(2+) sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 e V and 3.22 e V. The photoluminescence(PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge(NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

关键词： In-doped ZnO nanoparticles sol–gel process structural and optical characterization

Pressure Drop of Non-Newtonian Liquid Flow Through Elbows

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Chinese Journal of Chemical Engineering 2000年第4期8卷 388-390页

作者： T.k.Banerjee s.k.DAs Chemical Engineering Department University of Calcutta92A.P.C.RoadCalcutta-700 009IndiaChemical Engineering DepartmentUniversity of Calcutta92A.P.C.RoadCalcutta-700 009India

Experimental data on the pressure drop across different types of elbow for non-Newtonian pseudoplastic liquid flow in laminar condition have been presented. A generalized correlation has been developed for predicting ... 详细信息

关键词： non-Newtonian liquid pseudoplastic elbow

Total and Extractable Manganese and Iron in some Cultivated Acid soils of India:status,Distribution and Relationship with some soil Properties

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Pedosphere 2014年第2期24卷 196-208页

作者： s.k.BEHERA A.k.sHUkLA Directorate of Oil Palm Research (DOPR) Indian Institute of soil science (IIss)

A total of 400 surface soil （0-15 cm） samples were collected from cultivated soils representing four soil series, namely, Hariharapur, Debatoli, Rajpora and Neeleswaram in Orissa, Jharkhand, Himachal Pradesh and kerala states of India, respectively, and were analyzed to measure the contents of total and extractable Mn and Fe, to establish the relationship among total and extractable Mn and Fe and soil properties, and to characterize the spatial distribution pattern of Mn and Fe in some cultivated acid soils of India. The contents of total as well as extractable Mn and Fe varied widely with extractants and soil series. However, the amounts of Mn or Fe extracted by diethylene triamine penta-acetic acid （DTPA）, Mehlich 1, Mehlich 3, 0.1 mol L-1 HC1 and ammonium bicarbonate DTPA （ABDTPA） were significantly correlated with each other （P 〈 0.01）. Based on the DTPA-extractable contents and the critical limits （2 mg Mn kg-1 soil and 4.5 mg Fe kg-1 soil） published in the literature, Mn and Fe deficiencies were observed in 7% 23% and 1%-3% of the soil samples, respectively. The content of soil organic carbon （sOC） had greater influence on total and DTPA-extractable Fe than did soil pH. Geostatistical analysis revealed that total and DTPA-extractable Mn and Fe contents in the acid soils were influenced by soil pH, sOC content, and exchangeable cations like potassium, calcium and magnesium. spatial distribution maps of total and DTPA-extractable Mn and Fe in soil indicated different distribution patterns.

关键词： micronutrients extractant geostatistical analysis spatial variability

Environmental threats to the Three Gorges Reservoir Region:Are mutagenic and genotoxic substances important?

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Journal of Environmental sciences 2015年第12期27卷 172-174页

作者： Paul k.s.Lam state key Laboratory in Marine Pollution Department of Biology and ChemistryCity University of Hong Kong

The Three Gorges Dam project（TGDP）,with a total static investment of 95.46 billion RMB（Us$10.97 billion）based on the 1993 price level,commenced in 1994 and was completed in *** creation of the Three Gorges Reservoir following the completion of the TGDP had brought about significant changes to the Three Gorges Reservoir Region（TGRR）,stretching from the town of sandouping in Hubei Province to the Jiangjin District of Chongqing *** TGDP has led to progressive urbanization and industrialization of the TGRR,accompanied by increased shipping activities,greater

关键词： Three Gorges Dam Persistent organic pollutants Yangtze River sediment Water