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Effects of geoclimatic factors on the variability in Pinus pinea cone, seed, and seedling traits in Turkey native habitats

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Ecological Processes 2020年第1期9卷 648-660页

作者： safa balekoglu Servet Caliskan Hüseyin Dirik Faculty of Forestry Silviculture DepartmentIstanbul University-CerrahpasaBahcekoySariyerIstanbulTurkey

Background:Stone pine(Pinus pinea L.)is harvested for its edible *** is an important forest tree species,and also plays an important role in *** afforestation activities strongly depend on the quality of seeds and *** eastern native populations of stone pine were analyzed,in terms of their geographical and climatic parameters,in order to identify their cone,seed,pine nut,and seedling *** this regard,we aimed to contribute to the reforestation,yield,and breeding of this ***:All native populations occur in the sub-humid bioclimatic zone,according to Emberger’s bioclimatic classification,ranging 74.7-63.2 of Emberger’s Q Index value(Q),which synthesizes humidity and temperature,with lower values indicating more arid *** regard to geographical factors,altitude was found to have the greatest effect on cone diameter and seed weight,while there was a weak correlation of cone,seed,and pine nut dimension with longitude and *** terms of climatic factors,Q and mean of the maximum temperature of June,July,and August(ME)were found to be the main drivers behind significant effects in cone,seed,and pine nut morphometric *** most negative effect on seed number cone−1(r:−0.897),pine nut number cone−1(r:−0.923),pine nut yield(r:−0.903),and pine nut weight(r:−0.878)was Q,whereas cone diameter,seed length,and seed weight were positively correlated with the ME(r:0.939,r:0.889,and r:0.866,respectively).Cone and seed diameter and seed weight increased with decreasing summer drought index(r:−0.806,r:−0.846,and r:−0.866,respectively).Rainfall in the June of the third year prior to harvest time(RJ)had a negative effect on the percentage of sound seeds per *** rainfall in the third year prior to harvest time(AR)significantly affected pine nut weight(r:0.889),although rainfall during summer had a negative *** empty seed ratio of the different populations ranged from 20 to 68%,while considering

关键词： Bioclimatic zone Emberger Mediterranean Stone pine variation

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Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

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Controlling chaos based on a novel intelligent integral terminal sliding mode control in a rod-type plasma torch

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Chinese Physics B 2016年第5期25卷 11-22页

作者： safa Khari Zahra Rahmani Behrooz Rezaie Intelligent Systems Research Group Faculty of Electrical and Computer EngineeringBabol Noshrivani University of Technology

An integral terminal sliding mode controller is proposed in order to control chaos in a rod-type plasma torch *** this method, a new sliding surface is defined based on a combination of the conventional sliding surface in terminal sliding mode control and a nonlinear function of the integral of the system states. It is assumed that the dynamics of a chaotic system are unknown and also the system is exposed to disturbance and unstructured uncertainty. To achieve a chattering-free and high-speed response for such an unknown system, an adaptive neuro-fuzzy inference system is utilized in the next step to approximate the unknown part of the nonlinear dynamics. Then, the proposed integral terminal sliding mode controller stabilizes the approximated system based on Lyapunov＇s stability theory. In addition, a Bee algorithm is used to select the coefficients of integral terminal sliding mode controller to improve the performance of the proposed method. Simulation results demonstrate the improvement in the response speed, chattering rejection, transient response,and robustness against uncertainties.

关键词： chaos rod-type plasma torch intelligent integral terminal sliding mode control Bee algorithm

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CFD simulation of an industrial hydrocyclone with Eulerian-Eulerian approach: A case study

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International Journal of Mining Science and Technology 2014年第5期24卷 643-648页

作者： safa Raziyeh Soltani Goharrizi Ataallah Department of Chemical Engineering College of Engineering Shahid Bahonar University of Kerman

In the present study, a three-dimensional computational fluid dynamics simulation together with experimental field measurements was applied to optimize the performance of an industrial hydrocyclone at Sarcheshmeh copper complex. In the simulation, the Eulerian–Eulerian approach was used for solid and liquid phases, the latter being water. In this approach, nine continuous phases were considered for the solid particles with different sizes and one continuous phase for water. The continuity and momentum equations with inclusion of buoyancy and drag forces were solved by the finite volume method. The k–e RNG turbulence model was used for modeling of turbulency. There was a good agreement between the simulation results and the experimental data. After validation of the model accuracy, the effect of inlet solid percentage, pulp inlet velocity, rod inserting in the middle of the hydrocyclone and apex diameter on hydrocyclone performance was investigated. The results showed that by decreasing the inlet solid percentage and increasing the pulp inlet velocity, the efficiency of hydrocyclone increased. Decreasing the apex diameter caused an increase in the hydrocyclone efficiency.

关键词： Hydrocyclone Finite volume method Computational fluid dynamics κ-ε RNC Sarcheshmeh copper complex

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Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： Ehsan safa Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

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HIGH-ORDER EXPLICIT TIME-INTEGRATORS FOR DISCONTINUOUS GALERKIN DISCRETIZATIONS OF THE MAXWELL EQUATIONS

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第1期4卷 132-153页

作者： H.FAHS M.safa LAMA Laboratory University Paris-Est Marne-la-Vallee UMR CNRS 80505 boulevard Descartes 77454 Marne-la-Vall´ee Cedex 2France INRIA Paris-Rocquencourt Domaine de Voluceau BP.10578153 Le Chesnay CedexFrance

We investigate the practical implementation of a high-order explicit time-stepping method based on polynomial approximations,for possible application to large-scale problems in *** the spatial discretization by a high-order discontinuous Galerkin method,we obtain a linear system of differential equations of the form,∂tY(t)=HY(t)+S(t),where H is a matrix containing the spatial derivatives and t is the time *** formal solution can be written in terms of the matrix exponential,exp(tH),acting on some *** introduce a general family of time-integrators based on the approximation of exp(tH)by Jacobi polynomial *** discuss the efficient implementation of this technique,and based on some test problems,we compare the virtues and shortcomings of the *** also demonstrate how these schemes provide an efficient alternative to standard explicit integrators for computing solutions over long time intervals.

关键词： Maxwell’s equations discontinuous Galerkin method time-stepping schemes

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Epithelial-mesenchymal transition:a hallmark in pancreatic cancer stem cell migration,metastasis formation,and drug resistance

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Journal of Cancer Metastasis and Treatment 2020年第1期6卷 425-439页

作者： Ahmad R.safa Department of Pharmacology and Toxicology Indiana University School of MedicineIndianapolisIN46202USA

Metastasis,tumor progression,and chemoresistance are the major causes of death in patients with pancreatic ductal adenocarcinoma(PDAC).Tumor dissemination is associated with the activation of an epithelial-tomesenchymal transition(EMT)process,a program by which epithelial cells lose their cell polarity and cell-tocell adhesion,and acquire migratory and invasive abilities to become mesenchymal stem cells(MSC).These MSCs are multipotent stromal cells capable of differentiating into various cell types and trigger the phenotypic transition from an epithelial to a mesenchymal ***,EMT promotes migration and survival during cancer metastasis and confers stemness features to particular subsets of ***,a major problem limiting our ability to treat PDAC is the existence of rare populations of pancreatic cancer stem cells(PCSCs)or cancer-initiating cells in pancreatic *** may represent sub-populations of tumor cells resistant to therapy which are most crucial for driving invasive tumor *** cells are capable of regenerating the cellular heterogeneity associated with the primary tumor when xenografted into ***,the presence of PCSCs has prognostic relevance and influences the therapeutic response of *** express markers of cancer stem cells(CSCs)including CD24,CD133,CD44,and epithelial specific antigen as well as the drug transporter ABCG2 grow as spheroids in a defined growth medium.A major difficulty in studying tumor cell dissemination and metastasis has been the identification of markers that distinguish metastatic cancer cells from cells that are normally circulating in the bloodstream or at sites where these cells *** highlights a linkage between CSC and *** this review,The current understanding of the PCSCs,signaling pathways regulating these cells,PDAC heterogeneity,EMT mechanism,and links between EMT and metastasis in PCSCs are *** information may provide potential therapeutic s

关键词： Pancreatic cancer cancer stem cells epithelial-mesenchymal transition metastasis drug resistance

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Selective metal leaching from technosols based on synthetic root exudate composition

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Journal of Environmental Sciences 2020年第10期32卷 85-92页

作者： Hussein Jaafar Kanbar Zeinab Matar Ghina Abed-AlHadi safa Veronique Kazpard Research and Aralysis Platform for Enuironmental Sciences(PRASE) Doctoral School of Sciences and Techrology(EDST)The Lebanese UniversityP.O.5Rafic Hariri CampusHadatLebanon Department of Chemistry UmeàUniversitySE-90187UmeàSweden Department of Earth and Life Sciences Faculty of SciencesThe Lebanese UniversityRafic Hariri CampusHadatLebanon Laboratory of Georesources Geosciences and Enuironment(1.2GE)Faculty of SciencesThe Lebanese UniversityFanarLebanon

This study focused on metal release from technosols induced by synthetic root exudate(SRE).The effect of SRE composition on metal release was studied using six *** was done by treating the technosols with SRE solutions having varying concentrations of low molecular weight organic acids (LMWOAs),namely oxalic,citric,and malic ***,the physico-chemical parameters (p H and electric conductivity),Ca,Mg,Fe,Zn,and Cu release (by atomic absorption spectroscopy,AAS),chemical changes (by Fourier transform infrared,FT-IR),and organic parameters (by fluorescence) were *** release showed to be dependent on the SRE composition and technosol *** acid selectively released Ca,Mg,Zn,and Cu from technosols in a concentration-dependent manner;oxalic acid showed a significant role in the release of Mg and *** relatively high LMWOA concentrations,particulate organo-mineral complexes ***,technosol weathering was seen by the dissolution of humic substances and ferriallophanes,which in turn caused metal ***,re-precipitation of these phases showed to re-sorb metals,thus underestimating the role of LMWOAs in metal ***,the selective metal leaching was highly dependent on the SRE composition and LMWOA concentrations on one hand,and on the mineral,organic,and organo-mineral components of the technosols on the *** understanding of such processes is crucial for proposing and implementing environmental management strategies to reduce metal leaching or for the beneficial re-usage of metals (e.g.,for agromining) from technosols.

关键词： Technosols Oxalic acid Citric acid Metals Desorption Organo-mineral complexes

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GIS approach for assessment of land suitability for different land use alternatives in semi arid environment in Jordan:Case study(Al Gadeer Alabyad-Mafraq)

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Information Processing in Agriculture 2019年第1期6卷 91-108页

作者： safa Mazahreh Majed Bsoul Doaa Abu Hamoor GIS Unit National Centre for Agricultural Research and Extension(NCARE)Baqa’Jordan

The semi arid lands of Jordan are fragile and severely degraded due to low rainfall and mismanagement of natural *** human demands increase,sustaining the productivity of land becomes more and more *** suitability evaluation can contribute towards better land management;mitigation of land degradation;and designing land use pattern that prevents environmental problems through segregation of competing land *** analysis allows identifying the main limiting factors for the agricultural production and enables decision makers to develop crop managements able to increase the land *** purpose of this study was to develop a Geographic Information System(GIS)based approach for land use suitability assessment in order to assist land managers to identify areas with physical limitations for different land use alternatives based on research criteria developed by FAO and modified by *** study was conducted using various data and maps incorporated within(GIS)in order to derive potential suitability for different Land Utilization Types(LUTs).Land suitability mapping was developed using an innovative approach that integrates soil and climatic data for land suitability *** maps for each land use were developed to show the suitability classes and display the spatial representation of soils suitable for *** output of suitability analyses provided not only the type of land use for which the land was suitable,but also information about the type of limitation(s)facing the utilization of the *** land use alternatives(scenarios)were formulated to improve and optimize the agricultural production in the study area.

关键词： Land utilization types Soil survey Land suitability criteria Suitability mapping GIS Scenarios

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Sm-doped CsBr crystal as a new radio-photoluminescence (RPL) material

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Journal of Rare Earths 2016年第8期34卷 769-773页

作者： Go Okada Yutaka Fujimoto Hironori Tanaka safa Kasap Takayuki Yanagida Graduate School of Materials Science Nara Institute of Science and Technology (NAIST) 8916-5 Takayama Ikoma Nara 630-0192 Japan Department of Applied Chemistry Graduate School of Engineering Tohoku University 6-6-07 Aoba Aramaki Aoba-ku Sendai 980-8579 Japan Department of Electrical and Computer Engineering University of Saskatchewan 57 Campus Dr. Saskatoon SK S7N5A9 Canada

Radio-photoluminescence （RPL） is a phenomenon seen in luminescent materials in which the appearance of new photolu- minescence （PL） emission is induced by an incident ionizing radiation such as X-rays; and the signal is stable even after the irradia- tion and during the PL measurement. Since the induced PL intensity is proportional to the irradiation dose, the RPL can be used in ra- diation measurements. The distinct advantage of RPL over the conventional thermally- or photo-stimulated luminescence （abbrevi- ated as TSL or PSL） dosimeters is the stability of response signal. With an RPL detector, it allows us to readout the signal multiple time without signal fading. In this work, we discovered that CsBr：Sm showed an RPL phenomenon by X-ray irradiation, and we characterized this new material as an RPL detector. While the sample showed PL emissions mainly in the visible range, after an X-ray irradiation additional emissions could be observed in the red to near-infrared range around 650-850 nm and 900-1000 nm and longer. The RPL response was fairly stable overall, but very interestingly the 650-850 nm signal slightly increased while the 900-1000 nm decreased during PL readout. The dynamic range was confirmed over 1-104 mGy with linear response.

关键词： radio-photoluminescence RPL CsBr Sm dosimeter X-rays rare earths

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