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Altitudinal variation in the reproductive performance of the Mediterranean shrub Rhamnus lycioides L.

Journal of Plant Ecology 2012年第3期5卷 330-336页

作者： Javier Gulías anna Traveset Research group on Plant Biology under Mediterranean Conditions Department of BiologyUniversitat de les Illes BalearsCarretera de Valldemossa km 7.507122-Palma de MallorcaBalearic IslandsSpain Institut Mediterrani d’Estudis Avancxats(CSIC-UIB) C/Miquel Marques 2107190 EsporlesMallorcaBalearic IslandsSpain

Aims Rhamnus lycioides ***(Rhamnaceae)is a perennial shrub native to the Mediterranean Basin distributed along an altitudinal gradient,from sea level up to 1000 m *** specific goals of our study were(i)to compare plant morphology between two contrasting populations,(ii)to determine the reproductive system of ***,quantifying the relative importance of insects and wind as pollen vectors,(iii)to test if pollen limitation differs between populations,(iv)to study the main factors influencing fruit set and(v)to compare plant reproductive performance(mass allocation to flowers,fruits and seeds)between the two *** In the present study,we examined plant morphology and the reproductive performance of *** *** contrasting environments in two populations located at the extremes of its altitudinal range in the island of Mallorca(Balearic Islands,Western Mediterranean Basin)along a 3-year *** morphology,the relative importance of insects and wind as pollen vectors,the pollen limitation to seed production and the plant reproductive performance(mass allocation to flowers,fruits and seeds)were *** Findings Rhamnus lycioides individuals showed a higher plant surface/plant height ratio at the mountain than at the *** species appeared to be ambophilous despite its inconspicuous flowers,although the relative importance of wind as a pollination vector was higher at the mountain than at the coastal *** set was much higher at the mountain,where pollen appeared to be a limiting *** contrast,fruit set was not limited by pollen availability at the coastal population,where resource(water and nutrients)limitation seemed to be more *** size was greater at the coast,in contrast to fresh fruit weight that was higher at the *** the relatively few differences between sites in precipitation patterns along the study period,water availability appeared to be the key factor explaining

关键词： ambophily fruit set Mediterranean vegetation pollen limitation reproductive performance

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Variation in the timing of river entry of Atlantic salmon (Salmo salar L.) in the Baltic

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Current Zoology 2009年第5期55卷 342-349页

作者： anna KUPARINEN Juha MERIL Department of Biological and Environmental Sciences

The timing of river entry in the Atlantic salmon is known to depend on genetic, demographic and environmental factors, but little is known about the relative magnitude of among population and among year variation and covariation in this respect in natural state Atlantic salmon rives. To investigate this, variability in the timing of river entry in three historical Finnish Atlantic salmon populations were analyzed using salmon trap data collected during 1870- 1902. The analyses reveled that 1 ） the timing of river entry differed substantially and consistently among the rivers, and that 2） variation among the rivers was much larger than variation among years. Annual variations were not explained by regional environmental conditions, whereas in one river the timing of the local flood peak was a significant predictor of the timing of river entry. Differences in the timing of salmon entry to geographically closely situated rivers suggests that a regionally fixed opening date for coastal fisheries might not be the best management strategy as it may lead to uneven exploitation of salmon populations from different rivers [ Current Zoology 55 （5）： 342 - 349, 2009] .

关键词： Atlantic salmon Coastal fisheries Fisheries management Freshwater entry Migration River entry

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Analytical and Observational Investigation of Colors Effects on Drag Reduction in Penguins

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Journal of Bionic Engineering 2022年第4期19卷 1036-1053页

作者： Grace Tenorio anna Zagrai William Allen Mostafa Hassanalian Department of Mechanical Engineering New Mexico TechSocorroNM87801USA Cottonwood Valley Charter School SocorroNM87801USA Depertment of Biosciences Swansea UniversitySwanseaSA28PPUK

All 18 extant species of penguin are strongly countershaded,having dark dorsal and light ventral *** this paper,the thermal effects of this body color in penguins are investigated through analytical and observational ***,a thermal analysis that takes into account the environmental characteristics of penguins’habitats,fluxes,and morphology is used to analytically calculate penguin dorsal surface ***,a turbulent analytical solution for a heated boundary layer over a flat plate is applied to show that the dark color on the top of the penguins’bodies is very effective at skin drag *** verify this result,a 2D model penguin is computationally analyzed at different temperatures,confirming in principle underwater skin drag reduction through color-based surface warming with efficiency savings of up to 30%.Finally,to study how color-based increases in body surface temperatures are maintained through foraging dives,thermal cameras are used to measure the surface temperature of captive penguins before and after *** study shows conceptually that dark dorsal coloration in penguins could have a significant influence on in-water drag.

关键词： Animal coloration Drag Energy balance Irradiation Penguin Thermal imaging Skin friction

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Acyclic improper colouring of graphs with maximum degree 4

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Science China Mathematics 2014年第12期57卷 2485-2494页

作者： FIEDOROWICZ anna SIDOROWICZ Elzbieta Faculty of Mathematics Computer Science and Econometrics University of Zielona G'ora

A k-colouring （not necessarily proper） of vertices of a graph is called acyclic, if for every pair of distinct colours i and j the subgraph induced by the edges whose endpoints have colours i and j is acyclic. We consider acyclie k-eolourings such that each colour class induces a graph with a given （hereditary） property. In particular, we consider aeyclic k-eolourings in which each colour class induces a graph with maximum degree at most t, which are referred to as acyclic t-improper k-colourings. The acyelic t-improper chromatic number of a graph G is the smallest k for which there exists an acyclic t-improper k-colouring of G. We focus on acyclic colourings of graphs with maximum degree 4. We prove that 3 is an upper bound for the acyclic 3-improper chromatic number of this class of graphs. We also provide a non-trivial family of graphs with maximum degree 4 whose acyclic 3-improper chromatic number is at most 2, namely, the graphs with maximum average degree at most 3. Finally, we prove that any graph G with A（G） ≤ 4 can be acyelically coloured with 4 colours in such a way that each colour class induces an acyclic graph with maximum degree at most 3.

关键词： acyclic colouring acyclic improper colouring bounded degree graph hereditary property

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An Optimized Perfectly Matched Layer for the Schrödinger Equation

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Communications in Computational Physics 2011年第1期9卷 147-179页

作者： anna Nissen Gunilla Kreiss Department of Information Technology Uppsala UniversityP.O.Box 337SE-75105 UppsalaSweden.

We derive a perfectly matched layer(PML)for the Schrödinger equation using a modal *** derive approximate error formulas for the modeling error from the outer boundary of the PML and the error from the discretization in the layer and show how to choose layer parameters so that these errors are matched and optimal performance of the PML is *** computations in 1D and 2D demonstrate that the optimized PML works efficiently at a prescribed accuracy for the zero potential case,with a layer of width less than a third of the de Broglie wavelength corresponding to the dominating frequency.

关键词： Schrödinger equation perfectly matched layer

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Transcriptome analysis shows nicotinamide seed treatment alters expression of genes involved in defense and epigenetic processes in roots of seedlings of Picea abies

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Journal of Forestry Research 2022年第4期33卷 1365-1375页

作者： Cecilia Laurell Torkel Berglund anna B.Ohlsson Department of Industrial Biotechnology School of Engineering Sciences in ChemistryBiotechnology and Health(CBH)KTH Royal Institute of Technology10691 StockholmSweden

Nicotinamide treatment of plants and plant cell cultures has been shown to promote defense and decrease levels of DNA *** the present study,we used RNA-seq technology to study overall changes in gene expression induced in roots of 3-month-old spruce(Picea abies)seedlings grown from nicotinamide-treated seeds to examine the molecular mechanisms underlying the defense *** 350 genes were identified as differentially expressed in roots after the seed *** response genes,including transcription factors MYB77 and LHY and two chitinase enzymes,were generally upregulated,whereas genes thought to be involved in epigenetic regulation such as DDM1,known to promote DNA methylation,were present at high frequency among the downregulated *** all samples,the expression of downregulated epigenetic-related genes was highly correlated with the nicotinamide treatment,indicating a common *** results support an earlier hypothesis regarding a potential role of nicotinamide as a defense-signal mediator.

关键词： DNA methylation Large-scale gene expression analysis Nicotinamide Picea abies Seed treatment

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Borderline resectable pancreatic cancer and vascular resections in the era of neoadjuvant therapy

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World Journal of Clinical Cases 2021年第20期9卷 5398-5407页

作者： Danko Mikulic anna Mrzljak Department of Surgery University Hospital MerkurZagreb 10000Croatia Department of Gastroenterology and Hepatology University Hospital Center ZagrebZagreb 10000Croatia

While pancreatic cancer is still characterized by early systemic spread and poor outcomes,the treatment of this disease has changed significantly in recent years due to major advancements in systemic therapy and advanced surgical *** use of effective neoadjuvant approaches combined with aggressive surgical operations within a multidisciplinary setting has improved *** resectable pancreatic cancer is characterized by tumor vascular invasion,and is a setting where the combination of potent neoadjuvant chemotherapy and aggressive surgical methods,including vascular resections and reconstructions,shows its full ***,this will lead to improved local control and curative treatment in a number of patients with this aggressive malignancy.

关键词： Pancreatic adenocarcinoma Borderline resectable Neoadjuvant therapy Venous resection Arterial resection Vascular reconstruction

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Thermal Efficiency Optimization of a Ground Source Heat Pump System by Assistant Preheating/Precooling: A Case Study on a Heating-Load Dominated Building

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Journal of Thermal Science 2022年第6期31卷 1948-1958页

作者： LUO Jin ZHANG Qi PRIESS anna ROHN Joachim Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China GeoZentrum Nordbayern University of Erlangen-NürnbergSchlossgarten 591054 ErlangenGermany

Operation strategies of Ground Source Heat Pump System(GSHPS) such as continuous or intermittent approaches have been extensively studied. In this work, a novel strategy was proposed to maximize the energy efficiency of GSHPS. In this approach, the buildings was first air-conditioned by the preheating/precooling mode and the rest thermal load was covered by the heat pump(HP) mode. The system performance can then be optimized by considering the combination of these two operating modes. A case study was made to examine the thermal performance of a GSHPS installed in Nuremberg, Germany. Thermal performance of the HP and the preheating/precooling operating modes was examined. The system was optimized by deploying the assistant preheating/precooling approach and over one-year period monitoring showed that the seasonal Coefficient of Performance(COP) of the GSHPS was 4.12 in winter and 5.01 in summer. These COP values are higher than that of the conventional GSHPS. Thus, this proposed strategy could be an efficient way to improve the thermal performance of GSHPS.

关键词： ground source heat pump system ground-air heat exchanger ground temperature response preheating and precooling

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Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： Giovanni Ricci anna Sommazzi Francesco Masi Alessandra Forni CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale Giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and *** some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction *** the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar *** behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

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Task-resource Scheduling Problem

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International Journal of Automation and computing 2012年第4期9卷 429-441页

作者： anna Gorbenko Vladimir Popov Department of Intelligent Systems and Robotics Ural State University

Cloud computing is a new and rapidly emerging computing paradigm where applications, data and IT services are provided over the Internet. The task-resource management is the key role in cloud computing systems. Task-resource scheduling problems are premier which relate to the efficiency of the whole cloud computing facilities. Task-resource scheduling problem is NP-complete. In this paper, we consider an approach to solve this problem optimally. This approach is based on constructing a logical model for the problem. Using this model, we can apply algorithms for the satisfiability problem (SAT) to solve the task-resource scheduling problem. Also, this model allows us to create a testbed for particle swarm optimization algorithms for scheduling workflows.

关键词： Clouds complexity theory scheduling satisfiability problem genetic algorithms

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