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Tire abrasion particles negatively affect plant growth even at low concentrations and alter soil biogeochemical cycling

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Soil Ecology Letters 2022年第4期4卷 409-415页

作者： eva F.Leifheit Hanna L.Kissener Erik Faltin Masahiro Ryo Matthias C.Rillig Freie Universitat Berlin Institut fur Biologie14195 BerlinGermany Berlin-Brandenburg Institute of Advanced Biodiversity Research 14195 BerlinGermany Leibniz Centre for Agricultural Landscape Research(ZALF) 15374 MünchebergGermany Brandenburg University of Technology Cottbus-Senftenberg 03046 CottbusGermany

Tire particles(TPs)are a major source of microplastic on land,and considering their chemical composition,they represent a potential hazard for the terrestrial *** studied the effectsof TPs at environmentally relevant concentrations alongawide concentrationgradient(0–160 mg g^(-1))and tested the effects on plant growth,soil pH and the key ecosystem process of litter decomposition and soil *** addition of TPs negatively affected shoot and root growth already at low *** litter decomposition slightly increased with lower additions of TPs but decreased later *** pH increased until a TP concentration of 80 mg g^(-1) and leveled off *** respiration clearly increased with increasing concentration of added *** growth was likely reduced with starting contamination and stopped when contamination reached a certain level in the *** presence of TPs altered a number of biogeochemical soil parameters that can have further effects on plant *** the quantities of yearly produced TPs,their persistence,and toxic potential,we assume that these particles will eventually have a significant impact on terrestrial ecosystems.

关键词： Microplastic pollution Tire particles Plant growth Soil respiration Soil pH Litter decomposition

MINIMIZING EXCITATION LIGHT LEAKAGE AND MAXIMIZING MEASUREMENT SENSITIVITY FOR MOLECULAR IMAGING WITH NEAR-INFRARED FLUORESCENCE

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Journal of Innovative Optical Health Sciences 2011年第3期4卷 301-307页

作者： BANGHE ZHU eva M.SEVICK-MURACA Center for Molecular Imaging The Brown Foundation Institute of Molecular Medicine The University of Texas Health Science Center at Houston Houston TX 77030USA

Near-infraredfluorescence(NIRF)imaging involves the separation of weakfluorescence signals from backscattered excitation *** measurement sensitivity of current NIRF imaging systems is limited by the excitation light leakage through *** this contribution,the authors demonstrate that the excitation light leakage can be suppressed upon using appropriatefilter combination and *** excitation light leakage and measurement sensitivity were assessed and compared in this study by computing the transmission ratios of excitation to emission light collected and the signal-to-noise ratios in well-controlled phantom studies with differentfilter combinations and *** appropriatefilter combinations and permutations,we observe as much as two orders of magnitude reduction in the transmission ratio and higher signal-to-noise ratio.

关键词： Molecular imaging fluorescence opticalfilter excitation light leakage noise floor

The many faces of cGAS:how cGAS activation is controlled in the cytosol,the nucleus,and during mitosis

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Signal Transduction and Targeted Therapy 2021年第8期6卷 2261-2263页

作者： Anna-Maria Herzner Martin Schlee eva Bartok Department of Cancer Immunology and Immune Modulation Boehringer Ingelheim Pharma GmbH&Co.KGBiberach an der RiBGermany lnstitute of Clinical Chemistry and Clinical Pharmacology University HospitalUniversity of BonnBonnGermany Unit of Experimental Immunology Department of Biomedical SciencesInstitute of Tropical MedicineAntwerpBelgium

In their recently published study in Science,Li et al.1 unravel how hyperphosphorylation and chromatin-tethering of the double-stranded(dsDNA)sensor cGAMP synthase(cGAS)prevent self DNA recognition during mitosis(Fig.1);providing important insight into how this innate immune sensor balances its essential function for pathogen defense against potential autoinflammation.

关键词： activation sensor insight

Magnetic modification of diamagnetic agglomerate forming powder materials

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Particuology 2016年第6期14卷 169-171页

作者： Ivo Safarik eva Baldikova Kristyna Pospiskova Mirka Safarikova Department of Nanobiotechnology Biology Centre ISB CAS Na Sadkach 7 370 05 Ceske Budejovice Czech Republic Regional Centre of Advanced Technologies and Materials Palacky University Slechtitelu 27 783 71 Olomouc Czech Republic Global Change Research Institute CAS Na Sadkach 7 370 05 Ceske Budejovice Czech Republic Department of Applied Chemistry Faculty of Agriculture University of South Bohemia Branisovska 1457 370 05 Ceske Budejovice Czech Republic

A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assisted synthesis. A suspension of the magnetic particles in water soluble organic solvent （methanol, ethanol, propanol, isopropyl alcohol, or acetone） was mixed with the material to be modified and then completely dried at elevated temperature. The magnetically modified materials were found to be stable in water suspension at least for 2 months.

关键词： Magnetic modification Magnetic separation Powdered material Magnetic iron oxide Microwave assisted synthesis

Towards Characterization of the Chloroplast NAD（P）H Dehydrogenase Complex

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Molecular Plant 2009年第6期2卷 1127-1140页

作者： Marjaana Suorsa Sari Sirpio eva-Mari Aro Department of Biology Plant Physiology and Molecular Biology University of Turku FI-20014 Turku Finland

The NAD（P）H dehydrogenase （NDH） complex in chloroplast thylakoid membranes functions in cyclic electron transfer, and in chlororespiration. NDH is composed of at least 15 subunits, including both chloroplast- and nuclear-encoded proteins. During the past few years, extensive proteomic and genetic research on the higher plant NDH complex has been carried out, resulting in identification of several novel nuclear-encoded subunits. In addition, a number of auxiliary proteins, which mainly regulate the expression of chloroplast-encoded ndh genes as well as the assembly and stabilization of the NDH complex, have been discovered and characterized. In the absence of detailed crystallographic data, the structure of the NDH complex has remained obscure, and therefore the role of several NDH-associated nuclear-encoded proteins either as auxiliary proteins or structural subunits remains uncertain. In this review, we summarize the current knowledge on the subunit composition and assembly process of the chloroplast NDH complex. In addition, a novel oligomeric structure of NDH, the PSI/NDH supercomplex, is discussed.

关键词： Arabidopsis maize tobacco NAD(P)H dehydrogenese chloroplast thylakoid membrane cyclic electron transfer photosystem I.

Subcellular Distribution of Glutathione Precursors in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第12期53卷 930-941页

作者： Barbara eva Koffler Romana Maier Bernd Zechmann University of Graz Institute of Plant Sciences 8010 Graz Austria Graz University of Technology Institute for Electron Microscopy and Fine Structure Research 8010 Graz Austria

Glutathione is an important antioxidant and has many important functions in plant development, growth and defense. Glutathione synthesis and degradation is highly compartment-specific and relies on the subcellular availability of its precursors, cysteine, glutamate, glycine and γ-glutamylcysteine especially in plastids and the cytosol which are considered as the main centers for glutathione synthesis. The availability of glutathione precursors within these cell compartments is therefore of great importance for successful plant development and defense. The aim of this study was to investigate the compartmentspecific importance of glutathione precursors in Arabidopsis thaliana. The subcellular distribution was compared between wild type plants （Col-0）, plants with impaired glutathione synthesis （glutathione deficient pad2-1 mutant, wild type plants treated with buthionine sulfoximine）, and one complemented line （OE3） with restored glutathione synthesis. Immunocytohistochemistry revealed that the inhibition of glutathione synthesis induced the accumulation of the glutathione precursors cysteine, glutamate and glycine in most cell compartments including plastids and the cytosol. A strong decrease could be observed in γ-glutamylcysteine （γ-EC） contents in these cell compartments. These experiments demonstrated that the inhibition of γ-glutamylcysteine synthetase （GSH1） - the first enzyme of glutathione synthesis - causes a reduction of γ-EC levels and an accumulation of all other glutathione precursors within the cells.

关键词： Arabidopsis cysteine glutamate glutathione glycine.

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俄罗斯对中国石油出口贸易问题研究

俄罗斯对中国石油出口贸易问题研究

作者： Podzhunas eva 沈阳理工大学

学位级别：硕士

在俄罗斯的对外贸易产品结构中,化石能源尤其是石油的出口占据着绝对优势,在2019年的全球石油工业领域中,俄罗斯已经成为全球排名第二的原油生产国。在欧美国家对俄罗斯的经济制裁后,俄罗斯的石油出口政策已经出现了明显的转变,加强与... 详细信息

在俄罗斯的对外贸易产品结构中,化石能源尤其是石油的出口占据着绝对优势,在2019年的全球石油工业领域中,俄罗斯已经成为全球排名第二的原油生产国。在欧美国家对俄罗斯的经济制裁后,俄罗斯的石油出口政策已经出现了明显的转变,加强与亚洲地区国家尤其是与中国的合作已经成为俄罗斯的主要方向。从俄罗斯的角度来看,俄罗斯离亚太地区不是很遥远,陆路交通、海路交通都十分的便利,俄罗斯的石油出口到亚太地区交通方便,成本低廉。此外,俄罗斯和中国建立了全天候的战略合作伙伴关系,中俄两国之间的关系拥有地缘政治和地理优势。快速发展的中国经济已经成为世界上第二大经济体,虽然中国也盛产石油,但由于巨大的需求量,中国也是世界上最大的石油净进口国家。对于中国来说,如何拥有安全、稳定的石油进口渠道,并且如何保障石油资源的供给安全,已经成为中国国家安全的重要现实问题。目前俄罗斯的石油资源有相当份额出口到中国,但由于历史的原因,中国大部分的石油进口来自中东和非洲,在中国石油进口的市场份额中,来自俄罗斯的占比并不高,竞争力也一般。因此,扩大俄罗斯对中国石油出口规模,是中俄两国需要迫切研究的问题。本文主要从六个方面研究俄罗斯对中国石油出口贸易问题。首先,阐述本文的研究主题、背景和意义,提出本文的研究内容和方法以及创新点。其次,介绍了石油出口的概念以及石油贸易的模式,重点阐述要素禀赋理论、贸易理论和比较优势理论的相关内容。然后,详细介绍了俄罗斯对中国石油出口的发展历程以及现状,重点分析了俄罗斯对中国石油出口的有利条件。第四,分析俄罗斯的能源政策存在不确定性、俄中石油贸易议价机制并不完善、俄罗斯对中国石油出口结构不合理、俄罗斯关税制度不完善、石油供应利益需要合理协调以及中俄双方的政治互信度不高等问题。第五对俄罗斯国内的影响因素以及国际上的影响因素进行重点分析。最后针对俄罗斯对中国石油出口存在的主要问题以及影响因素提出优化双方石油贸易合作的措施。

关键词：俄罗斯石油石油出口石油贸易出口贸易

Gromov Hyperbolicity of Riemann Surfaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 209-228页

作者： José M.RODRíGUEZ eva TOURIS Departamento de Matemáticas Universidad Carlos Ⅲ de MadridAvenida de la Universidad 3028911 LeganésMadridSpain

We study the hyperbolicity in the Gromov sense of Riemann surfaces. We deduce the hyperbolicity of a surface from the hyperbolicity of its ＂building block components＂. We also prove the equivalence between the hyperbolicity of a Riemann surface and the hyperbolicity of some graph associated with it. These results clarify how the decomposition of a Riemann surface into Y-pieces and funnels affects the hyperbolicity of the surface. The results simplify the topology of the surface and allow us to obtain global results from local information.

关键词： Gromov hyperbolicity hyperbolic Riemann surface

Simple phenols in tropical woods determined by UHPLC-PDA and their antioxidant capacities: an experimental design for Randall extraction using environmentally friendly solvents

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Journal of Forestry Research 2020年第3期31卷 819-826页

作者： Marie Bartakova eva Dvorackova Lucie Chromcova Petr Hrdlicka Department of Chemistry and Biochemistry Mendel University in BrnoZemedelska 161300 BrnoCzech Republic

A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants. Wenge, angelim vermelho, zebrano, merbau,tigerwood, angelim pedra, jatoba, angelim amargoso,massaranduba, and doussie woods were used in experiments. The effects of three independent variables and their interactions on the yields of cinnamic and benzoic acid derivates were analyzed using UHPLC-PDA. The most significant parameters were found to be solvent percentage,extraction volume, and extraction temperature. Optimal conditions for the extraction of phenolic compound contents were an 80℃ extraction temperature, a 30 mL extraction volume, and the use of pure water as the extraction solvent. The tested species of woods contained mainly cinnamic acid derivates. Water extracts after hydrolysis contained greater amounts of cinnamic acid derivates than those extracts from non-hydrolyzed *** total phenolics content was highest in water extracts of tigerwood, wenge and merbau;however, the extract of merbau wood was a stronger radical scavenger in ABTS?áassays: 34.11 ± 0.02 mM Trolox equivalents per g of dry extract. The main compounds possessing antioxidant activity in the extracts of vermelho wood assessed by UHPLC analysis were hydroxycinnamic acids.

关键词： Phenolic compounds Tropical woods Ultrahigh-performance liquid chromatography Antioxidant capacity