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Site index determination using a time series of airborne laser scanning data

Forest Ecosystems 2025年第1期12卷 93-103页

作者： Maria Åsnes Moan Ole Martin Bollandsås Svetlana Saarela Terje Gobakken Erik Næsset Hans Ole Ørka Lennart Noordermeer faculty of Environmental sciences and Natural Resource Management Norwegian University of Life SciencesÅs1432Norway

Site index(SI)is determined from the top height development and is a proxy for forest productivity,defined as the expected top height for a given species at a certain index *** Norway,an index age of 40 years is *** using bi-temporal airborne laser scanning(ALS)data,SI can be determined using models estimated from SI observed on field plots(the direct approach)or from predicted top heights at two points in time(the height differential approach).Time series of ALS data may enhance SI determination compared to conventional methods used in operational forest inventory by providing more detailed information about the top height *** used longitudinal data comprising spatially consistent field and ALS data collected from training plots in 1999,2010,and 2022 to determine SI using the direct and height differential approaches using all combinations of years and performed an external *** also evaluated the use of data *** of root mean square error obtained from external validation were in the ranges of 16.3%–21.4%and 12.8%–20.6%of the mean fieldregistered SI for the direct approach and the height differential approach,*** were no statistically significant effects of time series length or the number of points in time on the obtained *** assimilation did not result in any substantial improvement in the obtained *** a time series of ALS data did not yield greater accuracies compared to using only two points in time,a larger proportion of the study area could be used in ALS-based determination of SI when a time series was *** was because areas that were unsuitable for SI determination between two points in time could be subject to SI determination based on data from another part of the time series.

关键词： Site index Time series Airborne laser scanning Direct approach Height differential approach Data assimilation

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Thermodynamic Analysis of Ammonia Synthesis

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Journal of Applied Mathematics and Physics 2025年第1期13卷 1-10页

作者： Slavko Đurić Enes Varupa faculty of traffic University of East Sarajevo Doboj Bosnia and Herzegovina faculty of Polytehnic sciences International University of Travnik Travnik Bosnia and Herzegovina

The paper researches the effect of temperature on ammonia synthesis. The ammonia synthesis reaction N2(g)+3H2(g)=2NH3(g)is exothermic with a negative entropy change. ΔG0condition is fulfilled at lower temperatures up to 464 K. It is a constant equilibrium of the ammonia synthesis reaction K′p≫1at lower temperatures, which means that the NH3(g)) synthesis reaction is shifted in the direction of NH3(g) formation (higher production of ammonia). The downside of lowering the temperature is that more ammonia is obtained, but the reaction rate slows down. Above 464K, the free enthalpy of the NH3(g) synthesis reaction is greater than zero, so the reaction enters thermodynamically unfavorable conditions. By increasing the reaction temperature, the ammonia yield NH3(g) decreases in the equilibrium mixture. At 400 K, it is 0.5128 kmol/kmol (51.28%) and at 900 K, the synthesis process NH3(g) is practically complete.

关键词： Temperature Thermodynamic Functions Synthesis Ammonia

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A fractional-order improved FitzHugh–Nagumo neuron model

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Chinese Physics B 2025年第1期34卷 519-528页

作者： Pushpendra Kumar Vedat Suat Erturk faculty of Engineering and Natural sciences Istanbul Okan UniversityIstanbulTurkey Department of Mathematics Mathematics Research CenterNear East University TRNCMersin 10Turkey Department of Mathematics Faculty of Arts and SciencesOndokuz Mayis UniversityAtakum-55200SamsunTurkey

We propose a fractional-order improved Fitz Hugh–Nagumo(FHN)neuron model in terms of a generalized Caputo fractional *** the existence of a unique solution for the proposed model,we derive the numerical solution using a recently proposed L1 predictor–corrector *** given method is based on the L1-type discretization algorithm and the spline interpolation *** perform the error and stability analyses for the given *** perform graphical simulations demonstrating that the proposed FHN neuron model generates rich electrical activities of periodic spiking patterns,chaotic patterns,and quasi-periodic *** motivation behind proposing a fractional-order improved FHN neuron model is that such a system can provide a more nuanced description of the process with better understanding and simulation of the neuronal responses by incorporating memory effects and non-local dynamics,which are inherent to many biological systems.

关键词： FitzHugh-Nagumo neuron model generalized Caputo fractional derivative L1 predictor-corrector method stability error estimation

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Abrasive wear behavior of functionally graded Al_(3)Ti reinforced aluminum matrix composite

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China Foundry 2025年第1期22卷 45-54页

作者： Eylül Tuğçe Yaman Yildiz Ömer Savaş Muhammed Soner Başer Engin Kocaman Ince Shipping Group 34724IstanbulTurkey Yildiz Technical University Faculty of Naval Architecture and Maritime34349IstanbulTurkey Ministry of transport and Infrastructure General Directorate of Marine Affairs06338AnkaraTurkey Zonguldak Bulent Ecevit University Faculty of EngineeringDepartment of Aerospace Engineering67100ZonguldakTurkey

Aluminum alloys are widely used in industry due to their light *** alloys are generally exposed to abrasive wear,which diminishes their effective *** wear resistance of these alloys is enhanced by adding various reinforcements,however,this enhancement comes at the cost of reduced fracture *** paradox of increased wear resistance versus decreased fracture toughness in aluminum alloys can be resolved by using functionally graded materials (FGMs).This study focuses on the abrasive wear behavior of functional graded aluminum matrix composites reinforced with Al_(3)Ti *** wear properties of the composites were investigated by considering the characteristics of the composite such as matrix type and various composite zones,as well as the wear parameters such as abrasive particle diameter,load,sliding speed and *** method was used in the abrasive wear tests in order to get more reliable results in a timeefficient *** recipes were created based on the L_(27)(3^(6)) orthogonal *** a result of the study,it is observed that the wear resistance of the composites increases with an increase in Al_(3)Ti reinforcement content and hardness of the *** addition,the size of abrasive particles and the applied load are significant factors affecting abrasive wear.

关键词： functionally graded Al_(3)Ti Taguchi abrasive wear

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Doline susceptibility mapping using multisource data in the karst aquifers of Saldaran mountain,High Zagros Belt

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Journal of Mountain Science 2025年第2期22卷 422-435页

作者： Peyman MOHAMMADI-AHMADMAHMOUDI Somaiyeh KHALEGHI Mohsen EHTESHAMI-MOINABADI Department of Physical Geography Faculty of Earth SciencesShahid Beheshti UniversityTehran ***Iran Department of Sedimentary Basins and Petroleum Faculty of Earth SciencesShahid Beheshti UniversityTehran ***Iran

Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of *** this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology *** 8 parameters have been inputted to the model which had correlation with *** this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for *** results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate ***,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab ***,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,*** evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model.

关键词： Doline susceptibility mapping UAV photogrammetry Karst aquifers Generalized linear model(GLM) High Zagros Belt

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Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells

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Neural Regeneration Research 2025年第2期20卷 598-608页

作者： Daniella Da Silva Madeleen Jansen van Rensburg Anine Crous Heidi Abrahamse Laser Research Centre Faculty of Health SciencesUniversity of JohannesburgDoornfonteinJohannesburgSouth Africa

Photobiomodulation,originally used red and near-infrared lasers,can alter cellular *** has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of *** this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain *** investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/*** adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory *** findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control ***,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal *** biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic ***,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.

关键词： differentiation inducers green photobiomodulation immortalized adipose-derived stem cell near-infrared photobiomodulation neurodegenerative disease neurogenesis photobiomodulation trans-differentiation

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Site index determination using a time series of airborne laser scanning data

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Forest Ecosystems 2025年第01期 93-103页

作者： Maria ?snes Moan Ole Martin Bollands?s Svetlana Saarela Terje Gobakken Erik N?sset Hans Ole ?rka Lennart Noordermeer faculty of Environmental sciences and Natural Resource Management Norwegian University of Life Sciences

Site index (SI) is determined from the top height development and is a proxy for forest productivity,defined as the expected top height for a given species at a certain index *** Norway,an index age of 40 years is *** using bi-temporal airborne laser scanning (ALS) data,SI can be determined using models estimated from SI observed on field plots (the direct approach) or from predicted top heights at two points in time (the height differential approach).Time series of ALS data may enhance SI determination compared to conventional methods used in operational forest inventory by providing more detailed information about the top height *** used longitudinal data comprising spatially consistent field and ALS data collected from training plots in 1999,2010,and 2022 to determine SI using the direct and height differential approaches using all combinations of years and performed an external *** also evaluated the use of data *** of root mean square error obtained from external validation were in the ranges of 16.3%–21.4%and 12.8%–20.6%of the mean fieldregistered SI for the direct approach and the height differential approach,*** were no statistically significant effects of time series length or the number of points in time on the obtained *** assimilation did not result in any substantial improvement in the obtained *** a time series of ALS data did not yield greater accuracies compared to using only two points in time,a larger proportion of the study area could be used in ALS-based determination of SI when a time series was *** was because areas that were unsuitable for SI determination between two points in time could be subject to SI determination based on data from another part of the time series.

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Enhancing Plant Resilience to Abiotic Stress:The Power of Biostimulants

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Phyton-International Journal of Experimental Botany 2025年第1期94卷 1-31页

作者： Su-Ee Lau Lucas Wei Tze Lim Mohd Fadhli Hamdan Colin Chan Noor Baity Saidi Janna Ong-Abdullah Boon Chin Tan Centre for Research in Biotechnology for Agriculture Universiti MalayaKuala Lumpur50603Malaysia faculty of Science Universiti MalayaKuala Lumpur50603Malaysia School of Biological sciences Universiti Sains MalaysiaGeorge Town11800Malaysia School of Biology Faculty of Applied SciencesUiTM Shah AlamShah Alam40450Malaysia Department of Biotechnology Faculty of Applied SciencesUCSI UniversityCheras56000Malaysia Department of Cell and Molecular Biology Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra MalaysiaSerdang43400Malaysia

Abiotic stresses such as drought,heat,salinity,and heavy metal contamination severely affect global agricultural *** 2005 and 2015,droughts caused losses of approximately USD 29 billion in developing countries,and from 2008 to 2018,droughts accounted for over 34%of crop and livestock yield losses,totaling about USD 37 *** support the growing human population,agricultural output must increase substantially,necessitating a 60%–100%rise in crop productivity to meet the escalating *** address environmental challenges,organic,inorganic,and microbial biostimulants are increasingly employed to enhance plant resilience through various morphological,physiological,and biochemical *** biostimulants enhance plant resilience under abiotic stress through mechanisms such as abscisic acid signaling modulation,which regulates stomatal closure to reduce water loss during drought and heat ***,they aid in scavenging reactive oxygen species and stabilizing ion channels,mitigating oxidative damage,and maintaining ionic balance under stress conditions such as *** review summarizes recent advancements in applying these biostimulants,focusing on their roles in triggering morphological,physiological,biochemical,and molecular changes that collectively enhance plant resilience under stress *** also includes a bibliometric analysis of all articles published on biostimulants from 2019 to 2024 and explores future research *** was placed on optimizing biostimulant formulations and understanding their synergistic effects to maximize their efficacy under various stress *** integrating biostimulants into agricultural practices,we can adopt a sustainable strategy to safeguard crop productivity in the face of climate change and environmental stressors.

关键词： Abiotic stress crop improvement microbial plant growth promoting rhizobacteria protein hydrolysate seaweed

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Evidence for active generation and seepage of sub-salt natural gas/condensate blend in the east offshore Nile Delta, Egypt: Integrated geochemical, petrophysical and seismic attribute approaches

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Petroleum Science 2025年第1期22卷 130-150页

作者： Mahmoud Leila Ahmed A.Radwan Amir Ismail Emad A.Eysa Geology Department Faculty of Science Mansoura University School of Mining and Geosciences Nazarbayev University Department of Geology Faculty of Science Al-Azhar UniversityAssiut Branch Department of Geology Faculty of Science Helwan University Department of Physical and Environmental sciences Texas A&M University—Corpus Christi Geology Department Faculty of Science Zagazig University

Offshore Nile Delta in Egypt represents an enormous hydrocarbon province with recent projected gas and condensate discoveries of more than 50 trillion cubic feet “TCF”. Most of these occur in the post-salt hydrocarbon plays where biogenic gases are dominant. This study integrates organic geochemistry,seismic geomorphology and petrophysics in order to decipher the origin, and accumulation conditions of the wet gas/condensate blend in the Upper Miocene sub-salt Wakar Formation sandstones in Port Fouad Marine “PFM” Field, offshore Nile Delta. Hydrocarbon pay zones are scattered thin（ 1 w.t.%, hydrogen index“HI” > 200 mg HC/g TOC） and mature(Tmax> 430°C, vitrinite reflectance “VR” > 0.6 %R_o), source rocks are restricted to Upper Miocene Wakar and Oligo-Miocene Tineh formations. The latter contains more mature organofacies（up to 1.2 %R_o） and type II/III kerogen, thereby demonstrating a good capability to generate wet gases. The studied gas is wet and has thermogenic origin with signs of secondary microbial alteration, whereas the condensate contains a mixture of marine and terrestrial input. Molecular biomarkers of the condensate, isotopic and molecular composition of the gas reveals a generation of condensate prior to gas expulsion from the source. The Wakar sandstones have a heterogeneous pore system where three reservoir rock types（RRTI, RRTII and RRTIII）. RRTI rocks present the bulk composition of the Wakar pay zones. Spatial distribution of RRTI facies likely control the accumulation of the sub-salt hydrocarbons. Our results provide a new evidence on an active petroleum system in the sub-salt Paleogene successions in the offshore Nile Delta where concomitant generation of ga

关键词： Petrophysical evaluation Source rock Hydrocarbon geochemistry Biomarkers Gas chimneys Rock-typing

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Macrofaunal Paleocommunities and Microfacies Analysis from the Upper Cretaceous in North Eastern Desert of Egypt

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Acta Geologica Sinica(English Edition) 2025年第1期99卷 15-37页

作者： Saeed FAREED Yasser SALAMA Abdelaziz MAHMOUD Helwan University Faculty of SciencesGeology DepartmentHelwanCairo 11Egypt Beni-Suef University Faculty of SciencesGeology DepartmentBeni Suef 62511Egypt

The Upper Cretaceous successions of Wadi Umm-Khayshar,southern Galala Plateau,North Eastern Desert,Egypt,are composed of highly diversified faunas and subdivided from base to top into the Galala(Middle-Late Cenomanian),Maghra El Hadida(Latest Cenomanian-Late Turonian),Matulla(Coniacian-Santonian),and Sudr(Campanian-Maastrichtian)*** ammonite biozones are recorded in the studied section:Neolobites vibrayeanus,Vascoceras cauvini(late Cenomanian),Vascoceras proprium,Choffaticeras segne,and Coilopoceras requienianum(Turonian)*** paleoenvironments of the Upper Cretaceous succession are interpreted based on detailed study and microfacies analysis that reflect a deposition in a homoclinal ramp platform ranging from intertidal to deep *** paleoecology of the Cenomanian-Turonian succession in the studied section is explained based on a detailed study of macrofaunal associations and sedimentary *** analysis(Q-mode cluster analysis,using the Raup-Crick Paired group method)of 1029 macrobenthic specimens,including 45 species of mollusks and echinoids yielded five macrofaunal associations(A-E)that are described and interpreted as remnants of *** nektonic elements are represented by 235 cephalopod specimens of 20 species;heatmap cluster analyses show the distribution of these specimens during the Upper Cenomanian-Turonian *** parameters(substrate consistency,rate of sedimentation,water energy,surface-water productivity,and oxygen availability)controlled the distribution of the studied *** five associations are divided into two major groups:low-stress associations(A,B,C,and D),and a highstress association(E).The low stress associations are recorded from two different habitats:(1)a high-energy,firm substrate habitat,dominated by epifaunal bivalves,large epifaunal gastropods and a regular echinoid;(2)a low-energy,soft substrate habitat dominated by infaunal bivalves and *** high stress associ

关键词： invertebrate paleontology ammonites Upper Cretaceous microfacies Southern Galala NE Egypt

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