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comparison of classical Models for Evaluating the Heat Requirements of Olive(Olea europeae L.) in Portugal

Journal of Integrative Plant Biology 2006年第6期48卷 664-671页

作者： helena Ribeiro Mário cunha Ilda Abreu Autonomous Section of Agricultural Sciences Faculty of Sciences University of Porto4485-661 VairaoPortugal Department of Botany Faculty of SciencesUniversity of Porto1191-4150 PortoPortugal Institute of Agricultural Sciences and Technology 4485-661 VairaoPortugal Department of Botany Faculty of Sciences University of Porto1191-4150 PortoPortugal Institute for Molecular and cell Biology 823-4150 PortoPortugal

The aim of the present study was to compare the accuracy and reproducibility of six statistical models for the calculation of olive （Olea europeae L.） heat requirements to trigger the onset of flowering in three Portuguese regions： Reguengos de Monsaraz, Valenga do Douro, and Braga. Other alms were to ascertain the date on which the heat-accumulation period started and the threshold temperatures above which the development of reproductive structures starts in olives. The starting and peak dates for the regional O. europeae flowering season were estimated by monitoring airborne pollen from 1998 to 2004 using ＂cour＂- type samplers. The threshold temperature values calculated for the three regions were very similar （9.0 ℃ for Valenca do Douro, 9.2 ℃ for Reguengos de Monsaraz, and 9.7 ℃ for Braga）. The accumulated daily mean temperature model had less interannual and inter-regional variation, showing best predictive results for 2004, with absolute differences between the observed and predicted dates of 4 d in Reguengos de Monsaraz and 2 d In Valenca do Douro and Braga for the onset of flowering date and of 2 d In Reguengos de Monsaraz, 7 d in Valenca do Douro, and 4 d in Braga for peak flowering dates. This model was the most accurate, reproducible, and operational to calculate heat requirements for olives to flower, with an average mean temperature accumulation of 1 446 ℃ In Reguengos, 1 642 ℃ in Valenga do Douro, and 1 703℃ In Braga to reach the onset of flowering. The best initial date for this accumulation was 1 January.

关键词： flowering season heat requirements olives pollen Portugal

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Quasiparticle approach to diffusional atomic scale self-assembly of complex structures: from disorder to complex crystals and double-helix polymers

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npj computational Materials 2016年第1期2卷 256-264页

作者： Mykola Lavrskyi helena Zapolsky Armen G Khachaturyan GPM UMR 6634University of RouenSaint-Etienne du RouvrayFrance Department of Materials Science&Engineering Rutgers UniversityPiscatawayNJUSA Department of Materials Science&Engineering University of CaliforniaBerkeleyBerkeleyCAUSA

A self-organisation is an universal phenomenon in nature and,in particular,is highly important in materials *** goal was to develop a new theory that provides a computationally effective approach to this *** this paper a quasiparticle theory of a diffusional self-organisation of atoms in continuum space during the diffusional time scale has been *** became possible due to two novelties,a concept of quasiparticles,fratons,used for a description of dynamic degrees of freedom and model Hamiltonian taking into account a directionality,length and strength of interatomic *** illustrate a predictive power and achievable level of complexity of self-assembled structures,the challenging cases of self-assembling of the diamond,zinc-blende,helix and double-helix structures,from a random atomic distribution,have been successfully *** approach opens a way to model a self-assembling of complex atomic and molecular structures in the atomic scale during diffusional time.

关键词： diffusion helix particle

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Urban Park Soil and Vegetation: Effects of Natural and Anthropogenic Factors

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Pedosphere 2015年第3期25卷 392-404页

作者： Pariente SARAH helena Michaela ZHEVELEV Atar OZ Laboratory of Geomorphology and Soil Department of Geography and EnvironmentBar-Ilan University

Various soil surface components, such as trees, shrubs and biological crusts, and human recreational activities, e.g., barbecues and trampling by visitors, may divide the area of the urban park into smaller fragments/mieroenvironments, differentiated by their microenvironmental conditions, which may differ in soil and vegetation characteristics. The spatial changes in the soil and vegetation characteristics and their causes were investigated in an urban park located south of Tel Aviv-Jaffa, Israel. The area of the park is 0.5 km^2, including groves, a lake, lawns, and rest areas. Soil was sampled in nine microenvironments, of which seven were within the park： under ceratonia siliqua trees （csU）, under Ficus sycomorus trees （FLU）, rest area between tables under F. sycomorus （FIB）, rest area under tables under F. sycomorus （FIT）, open area with bare soil （OaS）, open area with biological crust cover （Oac）, and open area covered by herbaceous vegetation （OaV）. Two more microenvironments, planar and sloping open areas （coP and coS, respectively） in the vicinity of the park, were used as the controls. Electrical conductivity, concentrations of soluble ions （Mg^2＋, ca^2＋, Na^＋, K^＋ and HcO3）, pH, contents of organic carbon, calcium carbonate and moisture, and grain size distribution were determined. In addition, herbaceous vegetation cover, number and diversity of herbaceous vegetation species were measured. It was found that soil properties and herbaceous vegetation characteristics varied within the park. Soil organic carbon, electrical conductivity, soluble salts, penetration depth, and vegetation characteristics were affected by human activities, mainly in the rest area between the tables. In contrast, the above characteristics were affected by natural factors mainly in the rest of the microenvironments, which were subjected to low levels of anthropogenic intervention. The heterogeneous structure of the park, as represented by the various microenvironments, offered new

关键词： anthropogenic activity herbaceous vegetation microenvironment soil properties species diversity

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Trade-offs between wood production and forest grouse habitats in two regions with distinctive landscapes

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Forest Ecosystems 2020年第2期7卷 274-289页

作者： helena Haakana Esa Huhta Hannu Hirvelä Tuula Packalen Natural Resources Institute Finland(Luke) PO Box 2FI-00791 HelsinkiFinland Natural Resources Institute Finland(Luke) PO Box 16FI-96301 RovaniemiFinland Natural Resources Institute Finland(Luke) PO Box 68FI-80101 JoensuuFinland.

Background:Forest management affects the viability of forest grouse populations,causing alterations to habitat *** the regional level,common targets for wood harvesting and safeguarding of specific habitats are negotiated between various *** potential trade-offs between forest grouse habitats and wood production in the region could support resource-smart decision ***:In this paper,we compiled trade-off curves represented as production possibility frontiers demonstrating the relationship between forest grouse habitat area and wood removal,using a Finnish forestry dynamics model and the Finnish Multi-Source National Forest *** the modelling of forest grouse habitats,a landscape-level occurrence model based on nationwide wildlife triangle census data was *** alternative forest scenarios in terms of wood removal were compiled for two study areas in Finland representing two different landscape *** and conclusions:Results showed that impacts on forest grouse habitats were *** the southern study area,increasing the roundwood harvesting rate affected grouse habitats more strongly as forests were already fragmented for other land uses and became more spruce-dominated over *** the maximum sustainable removal rate was implemented,predicted grouse habitat area was 55%less than in a no-removal *** the eastern study area,a more heavily forested region,the decrease was far lower at 22%.Scenario results were also compared to levels of recorded(business as usual)wood removal and that envisaged by valid regional forestry programmes,and their sustainability in terms of grouse habitat area was *** production possibility frontiers calculated in this study support the evaluation of the loss of suitable habitat caused by different wood harvesting rates,or vice versa,the economic cost of increasing habitat areas.

关键词： Forest grouse Forest landscape Habitat model Production possibilities frontier Scenario analyses Wood production

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Arbuscular mycorrhizal fungal community assembly in the Brazilian tropical seasonal dry forest

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Ecological Processes 2017年第1期6卷 9-18页

作者： Tancredo Augusto Feitosa de Souza helena Freitas centre for Functional Ecology Department of Life SciencesUniversity of Coimbra3000-456 CoimbraPortugal

Introduction:Here,we compare the arbuscular mycorrhizal fungal(AMF)community composition in soils from the root zone of the exotic invasive species Prosopis juliflora(EXO soils)and soils from the root zone of the native species Mimosa tenuiflora(NAT soils)from five locations in the Brazilian tropical seasonal dry forest,Paraíba,Brazil,using morphological ***:AMF community composition in EXO and NAT soils were *** phosphorus,diversity index,spore abundance,and species richness were the main factors differing between the EXO and NAT *** general,the most dominant order present in the soils were Glomerales(44.8%)and Gigasporales(41.4%).The most abundant AMF genus in all studied soils was ***:Differences in AMF community composition were associated with(1)differences in the dominant plant species(*** ***)and(2)changes in soil chemical factors(soil,pH,total organic carbon,total nitrogen,and available P)in EXO *** results contribute to a deeper view of the AMF communities in exotic soils and open new perspectives for ecological processes involving AMF species and exotic plant species in the Brazilian tropical seasonal dry forest.

关键词： Glomeromycota AMF community AMF diversity Native plant species Exotic plant species caatinga

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Attitude toward preventive counseling and healthy practices among medical students at a colombian university

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Frontiers of Medicine 2015年第2期9卷 251-259页

作者： Luz helena Alba Nora Badoui Fabian Gil Department of Preventive and Social Medicine Pontificia Universidad Javeriana Bogota Colombia Department of clinical Epidemiology and Biostatistics Pontificia Universidad Javeriana Bogota Colombia

Unhealthy behaviors of medical students influence their attitudes toward preventive counseling. The burden of chronic diseases is continually growing in developing countries, emphasizing the need for the increased role of general practitioners in preventive counseling. The objective of this study was to describe the effect of medical training on the risk profiles and attitudes of medical students toward preventive counseling in a colombian university. Students in their first and fifth years of training were surveyed using the ＂Healthy Doctor = Healthy Patient＂ questionnaire to assess counseling attitudes; personal practices, such as risky drinking, smoking, inadequate nutrition, and non-compliance with physical activity recommendations; and the university environment. The association among these components was estimated, as well as the effect of the university environment. Risky drinking and smoking decreased from first to fifth year （59.3% vs. 37.1%, P = 0.021 and 31.5~ vs. 25.9%, P = 0.51, respectively）, whereas inadequate nutrition and non-compliance with physical activity recommendations increased. Physical activity （PA） was associated with positive counseling attitude （ORs： nutrition 7.6; alcohol 5.2; PA 10.6）. Areas governed by institutional policies that are emphasized in the curriculum positively affected student practices. PA promoted preventive counseling and healthy lifestyles most effectively. Universities should therefore strengthen their preventive medicine curricula and modify social determinants.

关键词： lifestyle medical students preventive medicine counseling universities schools medical

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Quantifying Electronic Effects in QM and QM/MM Biomolecular Modeling with the Fukui Function

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物理化学学报 2018年第1期34卷 81-91页

作者： QI helena W. KARELINA Maria KULIK Heather J. Department of chemical Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA. Department of chemistry Massachusetts Institute of Technology Cambridge MA 02139 USA.

Multi-scale quantum-mechanical/molecular-mechanical(QM/MM) and large-scale QM simulation provide valuable insight into enzyme mechanism and structure-property relationships. Analysis of the electron density afforded through these methods can enhance our understanding of how the enzyme environment modulates reactivity at the enzyme active site. From this perspective, tools from conceptual density functional theory to interrogate electron densities can provide added insight into enzyme function. We recently introduced the highly parallelizable Fukui shift analysis(FSA) method, which identifies how frontier states of an active site are altered by the presence of an additional QM residue to identify when QM treatment of a residue is essential as a result of quantum-mechanically affecting the behavior of the active site. We now demonstrate and analyze distance and residue dependence of Fukui function shifts in pairs of residues representing different non-covalent interactions. We also show how the interpretation of the Fukui function as a measure of relative nucleophilicity provides insight into enzymes that carry out S_N2 methyl transfer. The FSA method represents a promising approach for the systematic, unbiased determination of quantum mechanical effects in enzymes and for other complex systems that necessitate multi-scale modeling.

关键词：《物理化学学报》期刊编辑工作发行工作

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Response to Midgley:the costs of reproduction cannot differ between the sexes

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Journal of Plant Ecology 2022年第6期15卷 1312-1315页

作者： Miao Liu helena Korpelainen chunyang Li Department of Ecology College of Life and Environmental SciencesHangzhou Normal UniversityHangzhou 311121China Department of Agricultural Sciences Viikki Plant Science CentreUniversity of HelsinkiHelsinkiFinland Department of Tea Sciences College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China

Many studies have compared the reproductive cost and vegetative growth at a particular time *** our review(Liu et al.2021b),we summarized those results but did not compare absolute reproductive costs between the sexes(Hultine et al.2016;Juvany and Munné-Bosch 2016).Moreover,we did not propose that the observed vegetative and environmental differences between the sexes were the only reasons for differences in sexual functioning,especially in the spreading and receiving of pollen(Midgley 2022).

关键词： reproductive summarized Response

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Non-alcoholic fatty liver disease: What the clinician needs to know

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World Journal of Gastroenterology 2014年第36期20卷 12956-12980页

作者： Mariana Verdelho Machado helena cortez-Pinto Departamento de Gastrenterologia Laboratório de Nutri??o Hospital Universitário de Santa Maria Lisbon 1649-035 Portugal

Non-alcoholic fatty liver disease(NAFLD) is the most frequent cause of liver disease in the Western world. Furthermore, it is increasing worldwide, paralleling the obesity pandemic. Though highly frequent, only about one fifth of affected subjects are at risk of developing the progressive form of the disease, non-alcoholic steatohepatitis with fibrosis. Even in the latter, liver disease is slowly progressive, though, since it is so prevalent, it is already the third cause of liver transplantation in the United States, and it is predicted to get to the top of the ranking in few years. Of relevance, fatty liver is also associated with increased overall mortality and particularly increased cardiovascular mortality. The literature and amount of published papers on NAFLD is increasing as fast as its prevalence, which makes it difficult to keep updated in this topic. This review aims to summarize the latest knowledge on NAFLD, in order to help clinicians understanding its pathogenesis and advances on diagnosis and treatment.

关键词： Non-alcoholic fatty liver disease Metabolic syndrome Insulin resistance Epidemiology Pathogenesis Genetics Diagnosis Prognosis Management

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Degradation of duloxetine: Identification of transformation products by UHPLc-ESI(+)-HRMS/MS,in silico toxicity and wastewater analysis

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Journal of Environmental Sciences 2019年第8期31卷 113-123页

作者： Rodrigo A.Osawa Ana P.carvalho Olinda c.Monteiro M.conceicao Oliveira M.helena Florêncio centro de Química e Bioquímica Faculdade de Ciências Universidade de Lisboa Laboratório de FTIcR e Espectrometria de Massa Estrutural Faculdade de Ciências Universidade de Lisboa centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa

Duloxetine(DUL), an antidepressant drug, has been detected in surface water and wastewater effluents, however, there is little information on the formation of its transformation products(TPs). In this work, hydrolysis, photodegradation(UV irradiation) and chlorination experiments were performed on spiked distillated water, under controlled experimental conditions to simulate abiotic processes that can occur in the environment and wastewater treatment plants(WWTPs). Eleven TPs, nine from reaction with UV light and two from chlorine contact, were formed and detected by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, and nine of them had their chemical structures elucidated upon analyses of their fragmentation patterns in MS/MS spectra. The formation and degradation of the TPs were observed. The parent compound was completely degraded after30 min in photodegradation and after 24 hr in chlorination. Almost all TPs were completely degraded in the experiments. The ecotoxicity and mutagenicity of the TPs were predicted based on several in silico models and it was found that a few of these products presented more ecotoxicity than DUL itself and six TPs showed positive mutagenicity. Finally, wastewater samples were analyzed and DUL and one TP, possibly formed by chlorination process, were detected in the effluent, which showed that WWTP not only did not remove DUL, but also formed a TP.

关键词： High resolution mass spectrometry Duloxetine Degradation processes Transformation products Wastewater analysis In silico toxicity

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