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Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the Middle Atlas, Morocco

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Integrative Zoology 2014年第3期9卷 349-359页

作者： saâd HANANE Forest Research Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespread bird in Morocco(North Africa).I examined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human *** study area was in the Middle Atlas Tighboula mountain forest,Morocco,in a disturbed and an undisturbed *** data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this *** place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nesting density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).Grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting *** multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under variable environments.

关键词： breeding density Columba palumbus holm oak Middle Atlas Morocco nest location woodpigeon

IMPROVING SOLVER PERFORMANCE THROUGH REDUNDANCY

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Journal of Systems Science and Systems Engineering 2016年第3期25卷 303-325页

作者： Eduardo Lalla-ruiz Stefan Voβ Department of Computer Engineering and Systems University of La Laguna Spain Institute of Information Systems (IWI) University of Hamburg Germany Eseuela de Ingenierla Industrial Pontificia Universidad Catolica de Valparaiso (PUCV) Chile

It is well known that hierarchies of mathematical programming formulatlons with different numbers of variables and constraints have a considerable impact regarding the quality of solutions obtained once these formulations are fed to a commercial solver. In addition, even if dimensions are kept the same, changes in formulations may largely influence solvability and quality of results. This becomes evident especially if redundant constraints are used. We propose a related framework for information collection based on these constraints. We exemplify by means of a well-known combinatorial optimization problem from the knapsack problem family, i.e., the multidimensional multiple-choice knapsack problem （MMKP）. This incorporates a relationship of the MMKP to some generalized set partitioning problems. Moreover, we investigate an application in maritime shipping and logistics by means of the dynamic berth allocation problem （DBAP）, where optimal solutions are reached from the root node within the solver.

关键词： Erraticism redundant constraints multidimensional multiple-choice knapsack problem,dynamic berth allocation problem

Estimative of real number of infections by COVID-19 in Brazil and possible scenarios

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Infectious Disease Modelling 2020年第1期5卷 720-736页

作者： H.P.C.cintra F.N.Fontinele Physics Institute University of BrasiliaBrasiliaBrazil

This paper attempts to provide methods to estimate the real scenario of the novel coronavirus pandemic in Brazil,specifically in the states of sao Paulo,Pernambuco,Espirito santo,Amazonas and the Federal *** the use of a SEIRD mathematical model with age division,we predict the infection and death curves,stating the peak date for Brazil and above *** also carry out a prediction for the ICU demand in these states and for how severe possible collapse in the local health system would ***,we establish some future scenarios including the relaxation on social isolation and the introduction of vaccines and other efficient therapeutic treatments against the virus.

关键词： COVID-19 SEIRD Undernotification Brazil

Cellular Auxin Homeostasis： Gatekeeping Is Housekeeping

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Molecular Plant 2012年第4期5卷 772-786页

作者： Michel ruiz Rosquete Department of Applied Genetics and Cell Biology University of Applied Life Sciences and Natural Resources (BOKU) 1190 Vienna Austria Department of Plant Systems Biology VIB and Department of Plant Biotechnology and Bioinformatics Ghent University 9052 Gent Belgium

The phytohormone auxin is essential for plant development and contributes to nearly every aspect of the plant life cycle. The spatio-temporal distribution of auxin depends on a complex interplay between auxin metabolism and cell-to-cell auxin transport. Auxin metabolism and transport are both crucial for plant development; however, it largely remains to be seen how these processes are integrated to ensure defined cellular auxin levels or even gradients within tissues or organs. In this review, we provide a glance at very diverse topics of auxin biology, such as biosynthesis, conjugation, oxidation, and transport of auxin. This broad, but certainly superficial, overview highlights the mutual importance of auxin metabolism and transport. Moreover, it allows pinpointing how auxin metabolism and transport get integrated to jointly regulate cellular auxin homeostasis. Even though these processes have been so far only separately studied, we assume that the phytohormonal crosstalk integrates and coordinates auxin metabolism and transport. Besides the integrative power of the global hormone signaling, we additionally introduce the hypothetical concept considering auxin transport components as gatekeepers for auxin responses.

关键词： auxin conjugation auxin homeostasis auxin metabolism auxin transport.

Ecophysiology of egg rejection in hosts of avian brood parasites:new insights and perspectives

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Current Zoology 2021年第6期67卷 631-638页

作者： Francisco ruiz-RAYA Centro de Investigación Marina Universidade de VigoGEAVigo 36310Spain

Egg rejection is the most effective and widespread defense used by host species to counteract the extreme fitness costs frequently imposed by obligate avian brood ***,the proximate mechanisms underlying between-and within-individual variation in host responses remain poorly *** evidence suggests that egg rejection is dependent on individual physiological states,and draws attention to the role of hormones as mediators of flexible antiparasitic *** this perspective article,I outline recent advances in our understanding of the proximate factors that mediate egg rejection.I also point out some areas where knowledge remains still lacking,especially those related to the development and maintenance of effective cognitive functions,the potential role of oxidative stress,immunological state,and developmental stressors.I propose new hypotheses that stimulate future research on behavioral host responses toward brood parasitism.

关键词： cognitive performance condition-dependence corticosterone flexible responses prolactin

PYRIDINATION OF POLY(VINYL CHLORIDE) via A HOMOLYTIC PATHWAY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： sad Moulay Zakia Zeffouni Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

Changes in plant community diversity and aboveground biomass along with altitude within an alpine meadow on the Three-River source region

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Chinese Science Bulletin 2012年第27期57卷 3573-3577页

作者： sa WenJun AN LiZhe sa Wei Institute of Botany Science School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Science Qinghai UniversityXining 810008China

The grassland is an important component of terrestrial ecosystems and plays a significant role in biodiversity and ecosystem *** the present study,the changes of plant species diversity and aboveground biomass productivity were examined along with the altitude in natural alpine grassland in the source region of three rivers on the Qinghai-Tibetan *** experimental locations were selected with altitudes ranging from 3862 to 4450 m above sea level(a.s.l.).The results indicated that Kobresia pygmaea meadow,Kobresia humilis meadow and salix cupularis shrub meadow had higher indices of diversity and aboveground *** distribution of species diversity,richness and aboveground biomass showed similarly unimodal patterns across the altitude gradient with the highest indices appeared at mid-altitudes *** changing trend of species diversity,richness and evenness also showed significant unimodal patterns with total aboveground biomass,and the highest species diversity occurred at intermediate level of *** research would provide a valuable reference for the protection of grassland biodiversity and maintaining of the grazing ecosystem function in the source region of the Three Rivers.

关键词：植物群落多样性地上生物量海拔高度高寒草甸三江源地区植物物种多样性生态系统功能生物多样性

HALOMETHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOLYTIC PATHWAY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： sad Moulay Nadia Mehdi Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

Response of photosynthesis,growth,and acorn mass of pedunculate oak to diff erent levels of nitrogen in wet and dry growing seasons

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Journal of Forestry Research 2023年第1期34卷 167-176页

作者： Krunoslav Sever saša Bogdan ŽeljkoŠkvorc Faculty of Forestry and Wood Technology University of ZagrebSvetošimunska 2510000 ZagrebCroatia

The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of pedunculate oak during 2010 in the absence of drought stress and during 2011 under the impact of moderate drought *** to the results,moderate drought stress significantly reduced net photo synthetic rate,stem diameter increment and height growth increment,while acorn mass was not *** nitrogen nutrition significantly reduced the net photo synthetic rate and stem diameter increment only in the wet year,acorn mass in both wet and dry years,while height growth increment was not significantly reduced by suboptimal nitrogen nutrition in either *** results indicate that optimal nitrogen levels can stimulate photo synthetic rate and stem diameter increment of pedunculate oak only in the absence of moderate drought ***,the results show that moderate drought stress is a more dominant stressor for photosynthesis and growth of pedunculate oak than suboptimal nitrogen nutrition,while for acorn development,it is the more dominant stressor.

关键词： Quercus robur L. Drought stress Net photosynthic rate Stem diameter increment Height growth increment Acorn mass