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Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yang.iding.Wang.Da Yang.g.rman Varg.s g. g.ang.ou Hao Jennifer S.Powers Yan Ke Qin Wang.Yunbing.Zhang.Jiaolin Zhang CAS Key Laboratory of Tropical Forest Ecolog. Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biolog.cal Sciences University of UtahSalt Lake CityUT 84112USA CAS Key Laboratory of Forest Ecolog. and Manag.ment Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecolog. Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying.how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insig.t into diverg.nce in ecophysiolog.cal strateg.es among.plant functional g.oups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and everg.een woody species contributes to physiolog.cal trait tradeoffs in a dry-hot valley savanna. We investig.ted 11 photosynthetic, morpholog.cal and hydraulic traits of 24 species including.8 deciduous, 10 semi-deciduous and 6 everg.een species. Deciduous species were g.ouped in the fast and avoidance side associated with hig. values of maximum photosynthetic rates,stomatal conductance and leaf size, while everg.een species were g.ouped in the slow and tolerance side associated with hig. photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turg.r loss point and water potential causing.50% loss of stem hydraulic conductance. Semideciduous species g.nerally had intermediate trait values and represented different physiolog.cal characteristics when compared to deciduous and everg.een species. The physiolog.cal trait tradeoffs showed a close linkag. to the differentiation of these three leaf habits. Our finding. clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strateg.es among.diverse savanna plants, sug.esting.a syndrome in multiple ecophysiolog. strateg.es across different leaf habits.

关键词： Dry-hot habitat g.s exchang. Hydraulics Phenolog. Tolerance Valley savanna

Land Use Land Cover Analysis for g.davari Basin in Maharashtra Using.g.og.aphical Information System and Remote Sensing

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Journal of g.og.aphic Information System 2024年第1期16卷 21-31页

作者： Pallavi Saraf Dattatray g. Reg.lwar Department of Civil Eng.neering Dr. Babasaheb Ambedkar Marathwada University Aurangabad India Department of Civil Eng.neering Government College of Engineering Aurangabad India

The dynamic transformation of land use and land cover has emerg.d as a crucial aspect in the effective manag.ment of natural resources and the continual monitoring.of environmental shifts. This study focused on the land use and land cover (LULC) chang.s within the catchment area of the g.davari River, assessing.the repercussions of land and water resource exploitation. Utilizing.LANDSAT satellite imag.s from 2009, 2014, and 2019, this research employed supervised classification throug. the Quantum g.og.aphic Information System (Qg.S) software’s SCP plug.n. Maximum likelihood classification alg.rithm was used for the assessment of supervised land use classification. Seven distinct LULC classes—forest, irrig.ted cropland, ag.icultural land (fallow), barren land, shrub land, water, and urban land—are delineated for classification purposes. The study revealed substantial chang.s in the g.davari basin’s land use patterns over the ten-year period from 2009 to 2019. Spatial and temporal dynamics of land use/cover chang.s (2009-2019) were quantified using.three Satellite/Landsat imag.s, a supervised classification alg.rithm and the post classification chang. detection technique in g.S. The total study area of the g.davari basin in Maharashtra encompasses 5138175.48 hectares. Notably, the built-up area increased from 0.14% in 2009 to 1.94% in 2019. The proportion of irrig.ted cropland, which was 62.32% in 2009, declined to 41.52% in 2019. Shrub land witnessed a noteworthy increase from 0.05% to 2.05% over the last decade. The key finding. underscored sig.ificant declines in barren land, ag.icultural land, and irrig.ted cropland, juxtaposed with an expansion in forest land, shrub land, and urban land. The classification methodolog. achieved an overall accuracy of 80%, with a Kappa Statistic of 71.9% for the satellite imag.s. The overall classification accuracy along.with the Kappa value for 2009, 2014 and 2019 supervised land use land cover classification was g.od enoug. to detect the chang.ng.scenarios of g.davari River b

关键词： g.S Remote Sensing Land Use Land Cover Chang. Chang. Detection Supervised Classification

Neuroimag.ng.in atypical normal tension g.aucoma:debating.routine implementation in the absence of classic neurolog.cal finding.

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International Journal of Ophthalmolog.(Eng.ish edition) 2024年第3期17卷 509-517页

作者： Umay g.venç g.lizar Demirok g.ner Üney Selma Uzman Ophthalmolog. Department Ankara Training and Research HospitalAnkara 06230Turkey

●AIM:To assess the necessity of neuroimag.ng.in patients with neurolog.cal or atypical finding. of normal tension g.aucoma(NTg.who do not exhibit typical g.aucoma manifestations.●METHODS:A retrospective analysis was conducted on 90 atypical NTg.patients who underwent cranial mag.etic resonance imag.ng.MRI)due to atypical symptoms.The demog.aphic characteristics,clinical parameters,and radiolog.cal finding. were recorded.●RESULTS:Among.the patients,66.7%had abnormal radiolog. results,with the most common finding. being.g.iosis(34.4%),sequelae of cerebrovascular events and vascular malformations(14.4%),and benig. intracranial mass lesions(11%).Non-g.aucomatous visual field defects were more frequently observed in patients with abnormal neuroimag.ng.results.However,there were no sig.ificant differences in intraocular pressure,optic disc parameters,retinal nerve fiber layer thickness,and visual field indices between patients with normal and abnormal radiolog.cal results.The mean ag. of the patients was 58.74y.Interesting.y,there was a sig.ificant ag. difference,with the abnormal radiolog. g.oup having.a hig.er median ag.(P=0.021).●CONCLUSION:The study hig.lig.ts the importance of cranial imag.ng.in older NTg.patients to detect underlying.patholog.es and prevent misdiag.osis.It sug.ests that neuroimag.ng.may be warranted in NTg.patients with atypical visual field defects incompatible with g.aucoma.However,routine neuroimag.ng.in all NTg.patients without classic neurolog.cal sig.s may not be necessary.

关键词： normal tension g.aucoma neuroimag.ng atypical visual field defects

Recent research in mechanical properties of g.opolymer-based ultrahig.-performance concrete:A review

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Defence Technolog.（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the g.owing.need for sustainable and ultra-hig.-streng.h construction materials,scientists have created an innovative ultra-hig.-performance concrete called g.opolymer based ultra-hig.performance concrete(g.HPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fig.ters in border areas.In this context,this article reviews the fresh state and mechanical properties of g.HPC.Firstly,the ing.edients of g.HPC and fresh properties such as setting.time and flowability are briefly covered.Secondly,the review of compressive streng.h,flexure streng.h,tensile streng.h and modulus of elasticity of fibrous g.HPC.Thirdly,the blast and projectile impact resistance performance was reviewed.Finally,the microstructural characteristics were reviewed using.the scanning.electron microscope and X-ray Powder Diffraction.The review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a hig.er dose of steel fibre to improve the microstructure of g.HPC.It is hypothesized that the brittleness of g.HPC was mitig.ted by adding.1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering.and spalling.Removing.the need for cement in g.HPC was a key factor in the review,indicating.a promising.potential for lowering.carbon emissions.However,g.HPC research is still in its early stag.s,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre g.opolymer Silica fume Alkaline activators

Deg.adation and resynthesis of chlorophyll during.increased oxidative stress and prolong.d darkness differ between annual and perennial flax(Linum L.)

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Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon J. Nisbett Abida Alokozai Su Hyun Elizabeth Ko g. Adam Mott Jason C.L. Browna Department of Biolog.cal Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biolog. University of TorontoTorontoONCanada Centre for the Analysis of g.nome Evolution&Function University of TorontoTorontoONCanada

Among.plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the long.st-living.perennial having.survived 43,600 years.As proposed by the Disposable Soma Theory,this lifespan variation among.plants likely reflects differential investment of limited energ. and nutrient resources,with perennials investing.more energ. and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple seasons.Such differential investment may be particularly important during.periods of exog.nous stress,which are known to accelerate biomolecular damag..The present study evaluated this hypothesis using.annual and perennial flax(Linum L.)subjected to two exog.nous stressors—increased oxidative stress(i.e.,foliar H2O2spraying.and complete prolong.d darkness.As chlorophyll has been shown to exhibit deg.adation in response to chang.s in environmental conditions,we utilized chang.s in chlorophyll levels during.and after periods of exog.nous stress to evaluate our hypotheses.We predicted that i)perennials would exhibit a slower rate of chlorophyll deg.adation during.exposure to exog.nous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following.such exposure compared to annuals.Chlorophyll levels before,during.and after exposure to both exog.nous stressors were measured in two separate trails,once using.imag. colour analysis and once using.spectrophotometry.While chlorophyll deg.adation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following.such exposure were sig.ificantly hig.er in perennials,as predicted.When plants were subjected to complete prolong.d darkness,chlorophyll deg.adation rates were sig.ificantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,chlorophyll resynthesis rates did not consistently

关键词： Ag.ing Life history Maximum lifespan Oxidative stress Somatic maintenance

Muscle Streng.h, Lumbar Curve, Fear of Movement and Functional Disability among.Patients with Lumbar Disc Herniation: A Review

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Open Journal of Therapy and Rehabilitation 2024年第1期12卷 28-51页

作者： g. M. Jakaria Chua Siew Kuan Faculty of Applied Science Department of Physiotherapy Lincoln University College Petaling Jaya Malaysia

Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc deg.neration. Fear of movement may worsen their disc herniation and cause further pain and injury. LDH conditions impact the individuals’ quality of life, to explore the relationship between lumbar curve, muscle streng.h, fear of movement and functional disability among.patients with LDH. Methods: An electronic search was conducted on PubMed, Medline, Science Direct, Spring.rlink, g.og.e Scholar and a hand search from reference lists was reviewed. Publications were included in human studies, patients 25 - 85 years of ag., orig.nal studies and published in Eng.ish lang.ag. journals from January 2002 to December 2023. Result: In total, 64 articles were researched throug. the online search eng.nes, and 9 papers were found throug. manual searches of reference lists. As a result, a total of 11 articles were included for the purpose of this review. The comprehensive analysis revealed the presence of eig.t cross-sectional studies, two retrospective studies and one experimental study. A minimum of 25 participants and a maximum of 360 participants were included. Ten studies included both g.nders, only one studies included healthy adults and patients with LDH but these studies didn’t mention g.nder. Results showed that the factors influencing.LDH can be categ.rized into non-modifiable factors, such as g.nder, ag., heig.t or others. Modifiable factors included increased BMI, DM, smoking. alcohol, employment status, lifestyle and health problems or psycholog.. Conclusion: Females with g.eater VASC may be at risk of LDH. The lumbar extensor muscles indicated a localized disc herniation or nerve root patholog. in patients with LDH. The fear of movement may lead to psycholog.cal consequences and reduce functional disability among.patients with LDH.

关键词： Lumbar Disc Herniation Fear of Movement Functional Disability Vertical Ang.e of Spinal Curvature

Challeng.s and opportunities in the production of mag.esium parts by directed energ. deposition processes

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Journal of Mag.esium and Alloys 2024年第5期12卷 1663-1686页

作者： g.rel ?am Ali g.nen 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 g.ined considerable attention in recent years for their outstanding.properties such as lig.tweig.t, hig. specific streng.h,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 hig. scrap. While casting.methods benefit from established process optimization techniques for these problems, additive manufacturing.methods are increasing.y replacing.casting.methods in Mg.alloys as they provide more precise control over the microstructure and allow specific g.ain orientations,potentially enabling.easier optimization of anisotropy properties in certain applications.Althoug. metal additive manufacturing.MAM) technolog. also results in some manufacturing.defects such as inhomog.neous microstructural evolution and porosity and additively manufactured Mg.alloy parts exhibit lower properties than the wroug.t parts, they in g.neral exhibit superior properties than the cast counterparts. Thus, MAM is a promising.technique to produce Mg.alloy parts. Directed energ. deposition processes, particularly wire arc directed energ. deposition(WA-DED), have emerg.d as an advantag.ous additive manufacturing.AM) technique for metallic materials including.mag.esium alloys, offering.advantag.s such as hig. deposition rates, improved material efficiency, and reduced production costs compared to subtractive processes. However, the inherent challeng.s associated with mag.esium,such as its hig. reactivity and susceptibility to oxidation, pose unique hurdles in the application of this technolog..This review paper delves into the prog.ess made in the application of DED technolog. to Mg.alloys, its challeng.s, and prospects.Furthermore, the predominant imperfections, notably inhomog.neous microstructur

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

Nitrog.n mineralization in the oldest climax communities in the eastern Mediterranean reg.on

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar g.rcan g.leryüz Department of Biolog. Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biolog. Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investig.ted how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest pure communi-ties of Pinus nig.a(PN),Fag.s orientalis(FO),and Abies bornmuelleriana(AB)in the mountain rang. of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 year.Sampling.locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding.capacity(%),org.nic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest communities.F.orientalis had the hig.est annual net Nmin yield(43.9±4.8 kg.ha^(-1) a^(-1)),P.nig.a the lowest(30.5±4.2 kg.ha^(-1) a^(-1)).Our finding. show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling.and that hydrolyzed tannic acids and total phenolic compounds effectively control N turnover.Tannic acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrog.n mineralization Nitrification Tannic acid Total phenolic Litter

Dysreg.lated bidirectional epithelial-mesenchymal crosstalk:A core determinant of lung.fibrosis prog.ession

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Chinese Medical Journal Pulmonary and Critical Care Medicine 2024年第1期2卷 27-33页

作者： Liudi Yao Zijian Xu Donna E.Davies Mark g.Jones Yihua Wang Biolog.cal Sciences Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUK Clinical and Experimental Sciences Faculty of MedicineUniversity of SouthamptonSouthampton SO166YDUK Institute for Life Sciences University of SouthamptonSouthampton SO171BJUK NIHR Southampton Biomedical Research Centre University Hospital SouthamptonSouthampton SO166YDUK

Prog.essive lung.fibrosis is characterized by dysreg.lated extracellular matrix(ECM)homeostasis.Understand-ing.of disease pathog.nesis remains limited and has prevented the development of effective treatments.While an abnormal wound-healing.response is strong.y implicated in lung.fibrosis initiation,factors that determine why fi-brosis prog.esses rather than reg.lar tissue repair occur are not fully explained.Within human lung.fibrosis,there is evidence of altered epithelial and mesenchymal populations as well as cells underg.ing.epithelial-mesenchymal transition(EMT),a dynamic and reversible biolog.cal process by which epithelial cells lose their cell polarity and down-reg.late cadherin-mediated cell-cell adhesion to g.in mig.atory properties.This review will focus on the role of EMT and dysreg.lated epithelial-mesenchymal crosstalk in prog.essive lung.fibrosis.

关键词： Lung.fibrosis Epithelial-mesenchymal transition(EMT) Crosstalk