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The influence of time and temperature on molecular gut content analysis： Adalia bipunctata fed with Rhopalosiphum padi

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Insect Science 2007年第5期14卷 353-358页

作者： STUART MCMILLAN anna-KARIN KUUSK anna CASSELLUNDHAGEN BARBARA EKBOM Department of Ecology Swedish University of Agricultural Sciences Box 7044 750 07 Uppsala Sweden

Gut content analysis is a useful tool when studying arthropod predator-prey interactions. We used polymerase chain reaction （PCR） technique to examine how detection of prey DNA in the gut content of predators was influenced by digestion time and temperature. Such knowledge is critical before applying PCR-based gut content analysis to field collected predators. Larvae of the two-spotted ladybeetle （Adalia bipunctata L.） were fed with the bird cherry-oat aphid （Rhopalosiphum padi L.） at either 21℃ or 14℃. After consuming one aphid, the predators were allowed to digest the prey for a range of time periods up to 24 hours. The influence of temperature on A. bipunctata feeding behavior was also recorded. From the fed larvae, total DNA was extracted and PCR reactions with R. padi specific primers were run. The number ofA. bipunctata that tested positive for R. padi DNA was negatively related to the length of digestion time. Temperature influenced larval feeding behavior but did not have a significant effect on R. padi DNA detection. After pooling the data from both temperature treatments we estimated the time point when R. padi DNA could be amplified from 50% of the fed A. bipunctata by PCR to be 4.87 hours. With such a rapid decrease in prey DNA detection success, positive PCR reactions will most likely be the result of predation events occurring shortly before capture. If a defined digestion temperature range has proven not to influence prey detection, PCR data obtained from predators collected within that particular range can be interpreted in the same way.

关键词： Adalia bipunctata aphidophagous predator prey DNA detection success gut content analysis PCR Rhopalosiphum padi

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The effect of growth conditions on the relationship between fine root and foliage biomass

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Journal of Forestry Research 2022年第5期33卷 1585-1591页

作者： Yury Karpechko anna Karpechko Andrej Tuyunen Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences 11 Pushkinskaya St.PetrozavodskKareliaRussia 185910

This article examines the physiological relationships between fine roots and foliage, and how their biomass ratio correlates with changes in stand quality class. The biomass of fine roots ≤ 3 mm in diameter of spruce stands in the Republic of Karelia (Northwest Russia) was determined by the soil monolith method. Foliage biomass was calculated using a previously designed technique from the standing stock, average height and quality class of the stand. A relation between fine-root: foliage biomass ratio and stand quality class (representing soil fertility) has been established. The closest correlation between fine-root: foliage biomass ratio and stand quality based on soil fertility was for the 1-2 mm root fraction. Analysis of the water flux balance in the trees revealed a correlation between fine-root: foliage ratio and the ratio of the specific volume of transpiration by the stand to the specific volume of water uptake from the soil by roots. Theoretical explanations for the decrease in fine-root: foliage biomass ratios with increasing stand quality class are offered.

关键词： Fine-root biomass Foliage biomass Stand quality class Soil fertility

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Radial and longitudinal density variations in Abies cephalonica and Pinus halepensis

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Journal of Forestry Research 2023年第3期34卷 853-863页

作者： Vasiliki Dimou anna Tsaliki Kyriaki Kitikidou Laboratory of Forest Technology Department of Forestry and Management of the Environment and Natural ResourcesDemocritus University of Thrace193 Pandazidou68200 OrestiadaPCGreece Laboratory of Forest Biometry-Biostatistics Department of Forestry and Management of the Environment and Natural ResourcesDemocritus University of Thrace193 Pandazidou68200 OrestiadaPCGreece

Basic wood density is an excellent indicator of quality,it is correlated with numerous physical,physiological and mechanical characteristics of a species and is a good descriptor of wood quality and important indicator of tree performance in community *** accurate method is thus needed to estimate wood *** standard way is to calculate the ratio of the oven-dried mass of a wood sample divided by its green volume,but wood characteristics within and between growth rings are highly variable;the density can vary in the longitudinal and the radial *** present study investigates the longitudinal and radial fl uctuations in the basic density of Abies cephalonica Loud and Pinus halepensis *** logs were cut from four diff erent trees for each species and 16 discs were formed(two discs from each log,one at the base and one at the top).Each disc was cut into cubes where their distance from the pith was measured and then sorted into 2 cm wide concentric *** results revealed a mild decreasing trend in basic density from the foot of the trunk upward for both *** pith in both species also seems to have a relatively high density,which in the immediate next growth rings decreases only to resume increasing toward the bark.

关键词： Aleppo pine Physical properties Specifi c gravity Wood quality

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Functionalised Poly(Vinyl Alcohol)/Graphene Oxide as Polymer Composite Electrolyte Membranes

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Journal of Renewable Materials 2019年第7期7卷 655-665页

作者： O.Gil-castell R.Cerveró R.Teruel-Juanes J.D.Badia A.Ribes-Greus Instituto de Tecnología de Materiales(ITM) Universitat Politècnica de València(UPV)Camino de Vera s/nValenciaSpain Departament d’Enginyeria Química Escola Tècnica Superior d’EnginyeriaUniversitat de València(UV)Av.de la Universitat s/nBurjassotSpain

Crosslinked poly(vinyl alcohol)(PVA)based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells(DEFC).The membranes were functionalised by means of the addition of graphene oxide(GO)and sulfonated graphene oxide(SGO)and crosslinked with sulfosuccinic acid(SSA).The chemical structure was corroborated and suitable thermal properties were *** the addition of GO and SGO slightly decreased the proton conductivity of the membranes,a significant reduction of the ethanol solution swelling and crossover was encountered,more relevant for those functionalised with *** general,the composite membranes were stable under simulated service *** addition of GO and SGO particles permitted to buffer the loss and almost retain similar proton conductivity than prior to *** membranes are alternative polyelectrolytes,which overcome current concerns of actual commercial membranes such as the high cost or the crossover phenomenon.

关键词： Direct ethanol fuel cell graphene oxide poly(vinyl alcohol) proton exchange membranes proton conductivity

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Stomatal regulation: Role of H2S-induced persulfidation in ABA signaling

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Molecular Plant 2021年第6期14卷 858-860页

作者： anna Siodmak Heribert Hirt DARWIN21 Center for Desert AgricultureKing Abdullah University of Science and TechnologyThuwalSaudi Arabia Max F.Perutz Laboratories University of ViennaDr.Bohrgasse 91030 ViennaAustria

Hydrogen sulfide(H2S)is an important signaling molecule in *** is a small gasotransmitter with high permeativity through lipid membranes.H2S can convert the mercapto groups(Cys–SH)of the amino acid cysteine into hydropersulfide groups(–Cys–SSH).This process is called *** modifications such as persulfidation can play an important role in protein functionality,altering protein conformation and/or *** plants,H2S can be generated within guard cells by CYSTEINE-DESULFHYDRASES,such as DES1,by degradation of cysteines into H2S,ammonia,and pyruvate(Zhang et al.,2020).H2S was reported to take part in physiological processes,such as stress response,and in the regulation of the functions of phytohormones such as salicylic acid and abscisic acid(ABA)(Pandey and Gautam,2020).Although the mechanism of how H2S affects ABA signaling pathways is not well understood,two recent studies by Chen et al.(2020)and Zhou et al.(2021)shed light on this topic,reporting how H2S-induced persulfidation regulates the stomatal ABA signaling pathway.

关键词： sulfide ammonia convert

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ON APPROXIMATELY(p,q)-WRIGHT AFFINE FUNCTIONS AND INNER PRODUCT SPACES

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Acta Mathematica Scientia 2016年第2期36卷 593-601页

作者： anna BAHYRYCZ Magdalena PISZCZEK Institute of Mathematics Pedagogical University

We prove, using the fixed point approach, some results on hyperstability （in normed spaces） of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characteriza... 详细信息

关键词： Hyperstability p-Wright affine function complex inner product space fixedpoint theorem

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Coordination of Plastid and Light Signaling Pathways upon Development of Arabidopsis Leaves under Various Photoperiods

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Molecular Plant 2012年第4期5卷 799-816页

作者： anna Lepisto Eevi Rintamaki Molecular Plant Biology Department of Biochemistry and Food Chemistry University of Turku FI-20014 Turku Finland

Plants synchronize their cellular and physiological functions according to the photoperiod （the length of the light period） in the cycle of 24 h. Photoperiod adjusts several traits in the plant life cycle, including flowering and senes- cence in annuals and seasonal growth cessation in perennials. Photoperiodic development is controlled by the coordinated action of photoreceptors and the circadian clock. During the past 10 years, remarkable progress has been made in under- standing the molecular mechanism of the circadian clock, especially with regard to the transition of Arabidopsis from the vegetative growth to the reproductive phase. Besides flowering photoperiod also modifies plant photosynthetic struc- tures and traits. Light signals controlling biogenesis of chloroplasts and development of leaf photosynthetic structures are perceived both by photoreceptors and in chloroplasts. In this review, we provide evidence suggesting that the photope- riodic development of Arabidopsis leaves mimics the acclimation of plant to various light intensities. Furthermore, the chloroplast-to-nucleus retrograde signals that adjust acclimation to light intensity are proposed to contribute also to the signaling pathways that control photoperiodic acclimation of leaves.

关键词： acclimation chloroplast biology circadian clock leaf/vegetative development light signaling photomor-phogenesis plastid signaling.

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Stochastic Gradient Descent for Linear Systems with Missing Data

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Numerical Mathematics(Theory,Methods and Applications) 2019年第1期12卷 1-20页

作者： anna Ma Deanna Needell Claremont Graduate University ClaremontCA 91711USA University of California Los AngelesLos Angeles CA 90095USA

Traditional methods for solving linear systems have quickly become imprac-tical due to an increase in the size of available *** massive amounts of data is further complicated when the data is incomplete or has missing *** this work,we address the obstacles presented when working with large data and incom-plete data *** particular,we propose to adapt the Stochastic Gradient Descent method to address missing data in linear *** proposed algorithm,the Stochastic Gradient Descent for Missing Data method(mSGD),is introduced and theoretical convergence guarantees are *** addition,we include numerical experiments on simulated and real world data that demonstrate the usefulness of our method.

关键词： Linear systems missing data iterative methods least squares problems

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Acyclic colorings of graphs with bounded degree

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Science China Mathematics 2016年第7期59卷 1427-1440页

作者： FIEDOROWICZ anna SIDOROWICZ Elzbieta Faculty of Mathematics Computer Science and Econometrics University of Zielona Góra

A k coloring(not necessarily proper) of vertices of a graph is called acyclic, if for every pair of distinct colors i and j the subgraph induced by the edges whose endpoints have colors i and j is acyclic. We consider some generalized acyclic k colorings, namely, we require that each color class induces an acyclic or bounded degree graph. Mainly we focus on graphs with maximum degree 5. We prove that any such graph has an acyclic 5 coloring such that each color class induces an acyclic graph with maximum degree at most 4. We prove that the problem of deciding whether a graph G has an acyclic 2 coloring in which each color class induces a graph with maximum degree at most 3 is NP complete, even for graphs with maximum degree 5. We also give a linear time algorithm for an acyclic t improper coloring of any graph with maximum degree d assuming that the number of colors is large enough.

关键词： acyclic coloring bounded degree graph computational complexity

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LEBESGUE DECOMPOSITION AND BARTLE-DUNFORD-SCHWARTZ THEOREM IN PSEUDO-D-LATTICES

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Acta Mathematica Scientia 2013年第3期33卷 653-677页

作者： anna AVALLONE Paolo VITOLO Dipartimento di Matematica e Informatica Università della BasilicataViale dell'Ateneo Lucano 10 85100 Potenza Italy

Let L be a pseudo-D-lattice. We prove that the exhaustive lattice uniformities on L which makes the operations of L uniformly continuous form a Boolean algebra isomorphic to the centre of a suitable complete pseudo-D-lattice associated to L. As a consequence, we obtain decomposition theorems such as Lebesgue and Hewitt-Yosida decompositions--and control theorems such as Bartle-Dunford Schwartz and Rybakov theorems--for modular measures on L.

关键词： Pseudo-effect algebra pseudo-D-lattice D-uniformity lattice uniformity mod-ular measure

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