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Height-diameter models for King Boris fir(Abies borisii regis Mattf.) and Scots pine(Pinus sylvestris L.) in Olympus and Pieria Mountains, Greece

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Journal of Mountain Science 2024年第5期21卷 1475-1490页

作者： Dimitrios I.RAPTIS Dimitra PAPADOPOULOU Angeliki PSARRA Athanasios A.FALLIAS Aristides G.TSITSANIS Vassiliki KAZANA Renewable natural resource Management and Bioeconomy Laboratory Department of Forest and Natural Environment SciencesInternational Hellenic University66100 DramaGreece

In forest science and practice, the total tree height is one of the basic morphometric attributes at the tree level and it has been closely linked with important stand attributes. In the current research, sixteen nonlinear functions for height prediction were tested in terms of their fitting ability against samples of Abies borisii regis and Pinus sylvestris trees from mountainous forests in central Greece. The fitting procedure was based on generalized nonlinear weighted regression. At the final stage, a five-quantile nonlinear height-diameter model was developed for both species through a quantile regression approach, to estimate the entire conditional distribution of tree height, enabling the evaluation of the diameter impact at various quantiles and providing a comprehensive understanding of the proposed relationship across the distribution. The results clearly showed that employing the diameter as the sole independent variable, the 3-parameter Hossfeld function and the 2-parameter N?slund function managed to explain approximately 84.0% and 81.7% of the total height variance in the case of King Boris fir and Scots pine species, respectively. Furthermore, the models exhibited low levels of error in both cases(2.310m for the fir and 3.004m for the pine), yielding unbiased predictions for both fir(-0.002m) and pine(-0.004m). Notably, all the required assumptions for homogeneity and normality of the associated residuals were achieved through the weighting procedure, while the quantile regression approach provided additional insights into the height-diameter allometry of the specific species. The proposed models can turn into valuable tools for operational forest management planning, particularly for wood production and conservation of mountainous forest ecosystems.

关键词： Generalized nonlinear weighted regression Monte Carlo cross-validation Mountainous ecosystems Quantile regression Central Greece

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Location of Disaster Management Bases Using Spatial Analysis

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 1-29页

作者： Hadi Nayyeri Sahar Zandi Mahmood Souri department of Geomorphology Faculty of Natural ResourceUniversity of KurdistanSanandajKurdistanIran department of Geography sciences Kharazmi UniversityTehranIran Red Crescent Society of the Islamic Republic Employee of Iran HamedanIran

Pre-crisis management involves the optimal selection of relief and rescue centers to minimize *** is particularly vulnerable due to its location on the Alpine-Himalaya seismic belt,resulting in an average death rate six times higher than the global average during ***,selecting appropriate relief and rescue centers is crucial to Iran’s disaster *** selecting the placement of rescue centers,accessibility and the appropriateness of the land should be taken into account as well as the distance from high-risk *** location of these centers does not require any particular *** address this issue,a study was conducted utilizing GIS,artificial neural networks,fuzzy logic,and mathematical models to determine the optimal placement based on 12 indicators within two clusters:natural and *** examine the information layers of the initial stage,a spatial data repository concerning the variables impacting the placement of these centers was established using *** functions and algorithms such as Fuzzy Logic in IDRISI,TOPSIS,and VIKOR software,the layers were assessed for weightage before being *** study’s analysis of the models used revealed that the positioning priority limits of the areas differed across all four ***,the areas with high desirability varied to a greater extent:the fuzzy model varied by 9.3%,neural network by 12.4%,VIKOR by 4.5%,and TOPSIS by 16.2%.The variance in results can be attributed to the differing levels of risk acceptance and non-acceptance in each ***,the study yielded other significant findings such as the correlation between study area size and model ***,smaller study areas exhibited higher model *** research also demonstrated that both fuzzy and VIKOR models achieved greater *** a result,employing these models in crisis management planning,particularly in pre-crisis management for identifying rescue center lo

关键词： Crisis management GIS earthquake risk site selection

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Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： Gürel ?am Ali Günen Iskenderun Technical University Faculty of Engineering and Natural Sciences Department of Mechanical Engineering Iskenderun Technical University Faculty of Engineering and Natural Sciences Department of Metallurgy and Materials Engineering

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight, high specific strength,and corrosion resistance, making them attractive for applications in medical, aerospace, automotive, and other transport industries. However,their widespread application is hindered by their low formability at room temperature due to limited slip systems. Cast Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high scrap. While casting methods benefit from established process optimization techniques for these problems, additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM) technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts, they in general exhibit superior properties than the cast counterparts. Thus, MAM is a promising technique to produce Mg alloy parts. Directed energy deposition processes, particularly wire arc directed energy deposition(WA-DED), have emerged as an advantageous additive manufacturing(AM) technique for metallic materials including magnesium alloys, offering advantages such as high deposition rates, improved material efficiency, and reduced production costs compared to subtractive processes. However, the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation, pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys, its challenges, and ***, the predominant im

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing (WAAM) 3-D printing High deposition rate

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Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray,Ethiopia

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Journal of Arid Land 2024年第1期16卷 1-13页

作者： Selam LJALEM Emiru BIRHANE Kassa TEKA Daniel H BERHE department of Land resources Management and Environmental Protection College of Dryland Agriculture and Natural ResourcesMekelle UniversityMekelle 231Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia Faculty of Environmental sciences and natural resource Management Norwegian University of Life Sciences(NMBU)Ås 1432Norway department of natural resources Management Adigrat UniversityAdigrat 50Ethiopia

Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic *** African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,*** farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,*** trees also could improve soil ***,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological ***,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental *** divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different *** collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil *** density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were *** revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under ***,and soil p H under ***,all the studied soils were improved under both species canopy as compared with canopy ***,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under *** two parkland agroforestry species significantly enhanced soil fertility near the canopy of top

关键词： agroforestry bulk density carbon stock dispersed tree soil texture tree canopy

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A comprehensive review on pharmacognosy, phytochemistry and pharmacological activities of 8 potent Prunus species of southeast Asia

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Journal of Traditional Chinese Medicine 2024年第3期44卷 620-628页

作者： Shikha Agrawal Adarsh Kumar Ankit Kumar Singh Harshwardhan Singh Suresh Thareja Pradeep Kumar department of Pharmaceutical sciences and natural Products Central University of Punjab

Genus Prunus comprising around 430 species is a vast important genus of family Rosaceae, subfamily amygdalaoidae. Among all 430 species, around 19 important species are commonly found in Indian subcontinent due to their broad nutritional and economic importance. Some most common species of genus Prunus are Prunus amygdalus, Prunus persica, Prunus armeniaca, Prunus avium, Prunus cerasus, Prunus cerasoides, Prunus domestica, Prunus mahaleb, etc. A newly introduced species of Prunus i.e Prunus sunhangii is recently discovered which is morphologically very similar to Prunus cerasoides. Plants of Prunus species are short to medium-sized deciduous trees mainly found in the northern hemisphere. In India and its subcontinent,it extends from the Himalayas to Sikkim, Meghalaya,Bhutan, Myanmar etc. Different Prunus species have been extensively studied for their morphological,microscopic, pharmacological and phytoconstituents characteristics. Total phenolic content of Prunus species explains the presence of phenols in high quantity and pharmacological activity due to phenols. Phytochemical screening of species of genus Prunus shows the presence of wide phytoconstituents which contributes in their pharmacological significance and reveals the therapeutic potential and traditional medicinal significance of this genus. Genus Prunus showed a potent antioxidant activity analyzed by 1,1-diphenyl-2-picryl-hydrazyl radical assay. Plant species belonging to the genus Prunus is widely used traditionally for the treatment of various disorders. Some specific Prunus species possess potent anticancer, anti-inflammatory,hypoglycemic etc. activity which makes the genus more interesting for further research and findings. This review is an attempt to summarize the comprehensive study of Prunus species from its distribution, morphological characters to phytoconstituents, and pharmacological activity.

关键词： Prunus Rosaceae antineoplastic agents distribution hypoglycemic agents phytochemistry review

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Tocotrienol isoforms:The molecular mechanisms underlying their effects in cancer therapy and their implementation in clinical trials

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Journal of Integrative Medicine 2024年第1期22卷 1-11页

作者： Maria Younes Ghady Loubnane Christopher Sleiman Sandra Rizk department of natural sciences Lebanese American UniversityByblosLebanon

Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as *** incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical *** literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic *** findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and *** current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and ***/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive *** an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.

关键词： Vitamin E Tocotrienols Cancer Molecular mechanism Clinical trials

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Dieback of managed spruce stands in western Germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan Gerhards Laura Griebel Klaus Fischer department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate *** recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle *** many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout *** this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term *** and community composition differed significantly among management categories,while different beetle fami-lies responded *** spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing *** proportion of forest specialists was highest in successional *** summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild ***,post-disturbance management should consider the landscape scale and include different management *** enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

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Tracing suspended and bed sediments during high and low water periods using geochemical characteristics-Case study:Vazrood watershed,northern Iran

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Journal of Mountain Science 2024年第2期21卷 470-483页

作者： KARIMI Nabiyeh GHOLAMI Leila KAVIAN Ataollah KHALEDI DARVISHAN Abdulvahed department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources UniversitySari ***Iran department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Iran

Complete and comprehensive information about sediment dynamic and identification of hotspots of sediment production and transport are necessary for understanding the erosion processes and increasing the efficiency of soil and water conservation *** studies used the sediment fingerprint techniques to investigate the contribution of different sources in suspended and bed sediment yield of the ***,the contribution of various land use/land covers in suspended and bed sediment yield for the great Caspian Sea basin is in an aura of ambiguity and the present study was conducted to gather information about an important part of this area in northern Iran,where rangelands are located upstream of Hyrcanian forests and dense agricultural lands are located *** surface soil of different land use/land covers including forest,rangeland,agriculture and streambank lands were sampled in 30 *** and bed sediments were sampled in the watershed outlet in two high and low water *** characteristics of soil and sediment samples containing 59 elements were measured using ICP-OES GBC *** reliable and suitable tracers from 59 elements were then selected using Range test,Kruskal-Wallis and Discriminant Function Analysis,respectively,in FingerPro package of R *** results showed that for suspended sediment,streambank and rangeland had the highest contributions of 86.2%and 47.5%,respectively,in two high and low water *** bed sediment,in two high and low water periods,rangeland and streambank had the highest contributions of 73.8%and 84.4%,*** use change and especially human activities such as agriculture,road construction and development of residential areas along the main river riparian zone has led to a significant increase in suspended and bed sediments.

关键词： Caspian Sea basin FingerPro Geochemistry Sediment transport Tracer combination

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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Impact of tourism on the vigilance behavior of the Cyprus rock agama(Laudakia cypriaca)

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Integrative Zoology 2024年第3期19卷 577-583页

作者： Artur GOLAWSKI Iris CHARALAMBIDOU Sylwia GOLAWSKA Faculty of sciences Siedlce University of Natural Sciences and HumanitiesSiedlcePolandand department of Life sciences School of Life and Health SciencesUniversity of NicosiaNicosiaCyprus

Escape behavior is a common antipredator strategy among wild ***,we investigated the effect of four factors on the vigilance behavior of the endemic Cyprus rock agama(Laudakia cypriaca).Flight initiation distance(FID,the minimum distance to which an observer can approach a lizard before it flees)was measured in relation to the type of location(tourist *** area),the observer’s starting distance,air temperature,and substrate *** collected data for 39 agamas in tourist areas and 34 of these lizards in nontourist *** a whole,the mean starting distance was 10.5 m and the FID was 3.6 *** average substrate temperature was 34.0℃ and the average air temperature 29.6℃.Only the type of area affected the agamas’escape decisions with FID being 1.8 m shorter in tourist areas than in nontourist areas(2.7 m vs.4.5 m).This is probably due to the habituation of lizards to the presence of humans in the former *** study shows that tourism strongly affects the behavior of lizards,which may have consequences for the functioning of the *** can increase the safety of lizards by creating a human shield to deter *** the tourist season is over,lizards may become more vulnerable to predators.

关键词： anthropogenic disturbance flight initiation distance lizards tourism vigilance behavior

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