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Biomass production,nutrient cycling and distribution in age-sequence Chinese fir(Cunninghamia lanceolate)plantations in subtropical China

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Journal of Forestry Research 2016年第2期27卷 357-368页

作者： Lili Zhou addo-danso daniel shalom Pengfei Wu Zongming He Chunhua Liu Xiangqing Ma Forestry College Fujian Agriculture and Forestry UniversityFuzhou 350002People's Republic of China Chinese Fir Engineering Technology Research Center of the State Forestry Administration Fuzhou 350002People's Republic of China Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British Columbia2424 Main MallVancouverBC V6T 1Z4Canada Ecosystem Services and Climate Change Division CSIR-Forestry Research Institute of GhanaBox 63 KNUSTKumasiGhana Xinkou Experimental Forest Farm of Fujian Agriculture and Forestry University Sanming 365002People's Republic of China

Biomass production and nutrient （N, P, K, Ca and Mg） accumulation, distribution and cycling were quantified in young, mature and over-mature （10-, 22-, and 34-year old） Chinese fir [Cunninghamia lanceolate （Lamb.） Hook] plantations in southern China. Total stand biomass of young, mature and over-mature stands was 38, 104 and 138 t ha-1 respectively. Biomass production increased significantly with age. Stem wood represented the highest percentage of stand biomass, accounting for 41, 55 and 63 % in the young, mature and over-mature plan- tations respectively. Nutrients concentration was highest in live needles and branches, and lowest in stem wood. The plantations accumulated more N, followed by K, Ca, Mg, and P. Nutrient return amount, nutrient utilization effi- ciency, nutrient turnover time, the ratio of nutrient return and uptake increased with stand age, which implies that young Chinese fir deplete soil nutrients to maintain growth, and efficiently utilize nutrients to decrease dependence on soil nutrients as they age. Harvesting young Chinese fir plantations would therefore lead to high nutrient loss, but prolonging the rotation length could improve soil recovery, and help sustain productivity in the long-term. Improved nutrient return through litterfall as stands get older may also be beneficial to nutrient pool recovery.

关键词： Cunninghamia lanceolate Biomassproduction Nutrient distribution Nutrient cycling

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Litterfall production and nutrient return in different-aged Chinese fir(Cunninghamia lanceolata) plantations in South China

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Journal of Forestry Research 2015年第1期26卷 79-89页

作者： Lili Zhou addo-danso daniel shalom Pengfei Wu Shubin Li Yayun Jia Xiangqing Ma Forestry College Fujian Agriculture and Forestry University Chinese fir Engineering Technology Research Center of the State Forestry Administration Faculty of Forestry University of British Columbia Ecosystem Services and Climate Change Division CSIR-Forestry Research Institute of Ghana

The amounts of litter produced and nutrients returned play a fundamental role in the productivity and biogeochemical and nutrient cycling of forest *** monitored annual litterfall production, nutrient return,and monthly dynamics over a one-year period in Chinese fir plantations aged 10, 22, and 34 years. Our objective was to quantify litterfall and nutrient return over a complete harvest rotation of Chinese fir. Annual litterfall production increased with stand age and was recorded as（3,294.6 ± 360.4）,（3,733.9 ± 211.2）, and（4,876.1 ± 212.8） kg ha-1a-1in stands aged 10, 22 and 34 years, respectively. Total litter production was significantly greater in the stand aged34 years than in the stand aged 10 years（p ／ 0.05）. With the exception of miscellaneous components, needle litterfall constituted the highest proportion（27.5–43.6 %）, followed by branches/twigs（9.5–16.6 %）. In all three plantations,annual total nutrient return to soil was in the order of C（1,119.95–2,709.05 kg ha-1a-1） [ N（39.32–62.04 kg ha-1a-1） [ K（15.95–22.44 kg ha-1a-1） [ P（1.30–1.63 kg ha-1a-1）. C, N, K and P input to soil was significantly lower in the 10-year-old stand in comparison to the 22- and34-year-old stands（p ／ 0.05）. Litterfall production and nutrient return（C, N and K） followed similar patterns, and C and N input to soil was significantly related to litterfall production（needle, branch and total litterfall）. C, N, P and K input to soil and total litterfall production were mainly driven by needle litterfall.

关键词： Cunninghamia lanceolata Litterfall production Nutrient return

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An emerging terpolymeric nanoparticle pore former as an internal recrystallization inhibitor of celecoxib in controlled release amorphous solid dispersion beads:Experimental studies and molecular dynamics analysis

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2669-2684页

作者： Jamie Anne Lugtu-Pe Xuning Zhang Sako Mirzaie Hao Han R.Chang Nour AL-Mousawi Kuan Chen Yongqiang Li Anil Kane daniel Bar-shalom Xiao Yu Wu Advanced Pharmaceutics and Drug Delivery Laboratory Leslie Dan Faculty of PharmacyUniversity of TorontoToronto M5S 3M2Canada Candoo Pharmatech Company Inc. Mississauga L5N 5M1Canada Department of Pharmacy University of CopenhagenCopenhagen DK-2100Denmark Patheon by Thermo Fisher Scientific Toronto Region Operations(TRO)Mississauga L5N 3X4Canada

Solid oral controlled release formulations feature numerous clinical advantages for drug candidates with adequate solubility and dissolution ***,most new chemical entities exhibit poor water solubility,and hence are exempt from such *** combining drug amorphization with controlled release formulation is promising to elevate drug solubility,like other supersaturating systems,the problem of drug recrystallization has yet to be resolved,particularly within the dosage ***,we explored the potential of an emerging,non-leachable terpolymer nanoparticle(TPN)pore former as an internal recrystallization inhibitor within controlled release amorphous solid dispersion(CRASD)beads comprising a poorly soluble drug(celecoxib)reservoir and insoluble polymer(ethylcellulose)*** to conventional pore former,polyvinylpyrrolidone(PVP),TPN-containing membranes exhibited superior structural integrity,less crystal formation at the CRASD bead surface,and greater extent of celecoxib ***-atom molecular dynamics analyses revealed that in the presence of TPN,intra-molecular bonding,crystal formation tendency,diffusion coefficient,and molecular flexibility of celecoxib were reduced,while intermolecular H-bonding was increased as compared to *** work suggests that selection of a pore former that promotes prolonged molecular separation within a nanoporous controlled release membrane structure may serve as an effective strategy to enhance amorphicity preservation inside CRASD.

关键词： Controlled release amorphous solid dispersion Poorly soluble drug Internal recrystallization Membrane-reservoir coated beads Molecular dynamics simulation Effect of pore formers Terpolymer nanogel Drug-polymer interactions

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Testing and modelling of transient adhesion phenomena in rolling-sliding contacts

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Friction 2024年第5期12卷 1016-1027页

作者： daniel KVARDA Alexander MEIERHOFER Klaus SIX Faculty of Mechanical Engineering Brno University of TechnologyBrno61669Czech Republic Virtual Vehicle Research GmbH Graz8010Austria

Transient adhesion effects in rolling–sliding contacts influence all aspects of train–track *** is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway *** study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle *** experimental data for the model are measured using a commercial ball-on-disc *** experimental results showed a liquid reservoir in front of the contact area that slowly reduces in *** observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it *** model was able to reproduce the occurrence of low adhesion region seen in experimental results with different particle concentrations.

关键词： coefficient of adhesion tribology transient effects wheel-rail contact

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Energy model based on solar potential and the production of electrical energy through living plants’photosynthesis

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Clean Energy 2024年第3期8卷 116-126页

作者： Raymond daniel Rodriguez Martinez Department of Industrial Production Faculty of EngineeringUniversidad Metropolitana1073 CaracasVenezuela

Developing a sustainable energy model is imperative considering the current trend towards decarbonizing sectors *** this purpose,Venezuela was used as a reference to propose an energy model focused on taking advantage of plant photosynthesis through microbial-vegetable fuel cells together with an agro-photovoltaic system to enhance energy and agricultural *** production from the cells was estimated using an average power density of 264 mW/m^(2) over 4%of the areas destined for crops in the entire Venezuelan region,obtaining an annual production of 19.889 GWh/*** contrast,the energy production of the agro-photovoltaic system was modelled using PVsyst software on 50%of the area used for the cells distributed throughout the states of Anzoátegui,Guárico,Monagas and Portuguesa according to their meteorological conditions,solar irradiation and agricultural activity,resulting in 3703417 GWh/*** resulting whole system proved to be able to cover>10 times the installed electricity generation capacity at a national level and,together with the tremendous scalability of the microbial fuel cells,it shows that Venezuela has a high potential for the production and distribution of clean energy.

关键词： ecosystems microbial fuel cell microorganisms renewable sustainability

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Beyond the code:the role of histone methylation in cancer resistance and therapy

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2837-2839页

作者： daniel Noerenberg Frederik Damm Charité–Universitätsmedizin Berlin corporate member of Freie Universität BerlinHumboldt Universität zu Berlinand Berlin Institute of HealthDepartment of HematologyOncologyand Cancer ImmunologyBerlinGermany German Cancer Consortium(Deutsches Konsortium für Translationale Krebsforschung DKTK)Partner SiteBerlinGermany

In a recently published paper in Nature,Yamagishi et *** a comprehensive exploration on the mechanistic basis and subsequent emergence of resistance of targeting histone H3 lysine trimethylation(H3K27me3)using the EZH... 详细信息

关键词： EZH2 resistance

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Plant-microbial fuel cell for electrical generation through living plants: an internal resistance insight into the plant species used

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Clean Energy 2024年第5期8卷 45-53页

作者： Raymond daniel Rodriguez Martinez Department of Industrial Production Faculty of EngineeringUniversidad Metropolitana1073 CaracasVenezuela

Climate change is a global threat,the presence of which has encouraged the development and implementation of renewable energies,including plant–microbial fuel cells,which could generate 6629568–33147840 MWh per year due to their large-scale *** of the main challenges associated with microbial cells is internal resistance—a parameter whose magnitude is influenced by sev-eral *** the case of plant–microbial fuel cells,adding a plant positively affects the mitigation of internal ***,the species employed is expected to play an important *** the present study,the objective was to determine as a general reference the internal resistance of cells using various plant species,among which were tomato(Solanum lycopersicum),black beans(Phaseolus vulgaris),aloe vera(Aloe vera),corn(Zea mays),and moss(Dicranidae).For this purpose,an experimental procedure was carried out to compare the manual voltage measurements with a free cell concerning the voltage obtained by adding an external resistor in *** internal resistance values were determined as a function of the measured voltage,obtaining 177,179,175,324,and 233 kΩfor aloe vera,corn,tomato,black beans,and moss,*** this,it was shown that the roots of the plants represent an essen-tial addition to the internal resistance of the cell in the short *** contrast,plants with a C4 photosynthetic metabolism are more favourable,while C3 plants can also benefit from internal resistance during a more extended period of rhizodeposition.

关键词： climate change energy microorganism renewable source voltage

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Assessment of scale interactions associated with wake meandering using bispectral analysis methodologies

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 65-75页

作者： Dinesh Kumar Kinjangi daniel Foti Department of Mechanical Engineering University of MemphisMemphisTennesseeUSA

Large atmospheric boundary layer fluctuations and smaller turbine-scale vorticity dynamics are separately hypothesized to initiate the wind turbine wake meandering phenomenon,a coherent,dynamic,turbine-scale oscillation of the far *** interactions,the mechanism of energy transfers between scales,manifest as triples of wavenumbers or frequencies and can be characterized through bispectral *** bispectrum,which correlates the two frequencies to their sum,is calculated by two recently developed multi-dimensional modal decomposition methods:scale-specific energy transfer method and bispectral mode ***-eddy simulation of a utility-scale wind turbine in an atmospheric boundary layer with a broad range of large length-scales is used to acquire instantaneous velocity *** bispectrum from both methods identifies prominent upwind and wake meandering interactions that create a broad range of energy scales including the wake meandering *** coherent kinetic energy associated with the interactions shows strong correlation between upwind scales and wake meandering.

关键词： Wind turbine wake Mode decomposition Bispectral analysis

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Numerical study on the use of soft material walls to enhance seismic performance of an existing tunnel

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Underground Space 2024年第2期15卷 90-112页

作者： Qiangqiang Sun Menghao Hou daniel Dias Institute of Geotechnical Engineering College of Civil Engineering and ArchitectureHebei UniversityBaoding 071002China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble 38000France

Seismic risk is one of the biggest challenges for tunnel safety,and several mitigation techniques have been proposed to enhance the seismic performance of existing *** paper aims to investigate the effectiveness of an innovative approach for reducing the seismic risk of existing tunnels by using soft material walls(SMW)symmetrically installed in the surrounding *** investigation is performed with a two-dimensional numerical model and the effectiveness of SMW in mitigating the seismic-induced lining forces is quantitatively evaluated by reduction *** influences of nonlinear properties of soil,SMW and tunnel lining on the isolation effectiveness are also *** parametric studies show that the computed reduction ratio is strongly affected by the modulus ratio between the SMW and the soil,the wall geometric parameter,and the flexibility *** is more effective for the thick and soft isolation walls that are inserted near a stiff tunnel in the soft *** tunnel seismic response can be reduced by up to 50%for the scenarios ***,the parametric study identifies an optimum normalized depth of SMW and recommends a relation between the maximum isolation effect and the flexibility ***,simple charts are suggested in this work for estimating the isolation effect in specific conditions of the soil and the *** these lines,the results of this work may be used in the seismic retrofitting of an existing tunnel,aiding the preliminary design of the isolation walls.

关键词： Tunnels Earthquakes Seismic analysis Isolation walls Soft material

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Fundamental error in tree-based machine learning model selection for reservoir characterisation

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Energy Geoscience 2024年第2期5卷 214-224页

作者： daniel Asante Otchere Centre of Excellence in Subsurface Seismic Imaging and Hydrocarbon Prediction Universiti Teknologi PETRONAS32610Seri IskandarPerak Darul RidzuanMalaysia

Over the past two decades,machine learning techniques have been extensively used in predicting reservoir *** this approach has significantly contributed to the industry,selecting an appropriate model is still challenging for most *** solely on statistical metrics to select the best model for a particular problem may not always be the most effective *** study encourages researchers to incorporate data visualization in their analysis and model selection *** evaluate the suitability of different models in predicting horizontal permeability in the Volve field,wireline logs were used to train Extra-Trees,Ridge,Bagging,and XGBoost *** Random Forest feature selection technique was applied to select the relevant logs as inputs for the *** on statistical metrics,the Extra-Trees model achieved the highest test accuracy of 0.996,RMSE of 19.54 mD,and MAE of 3.18 mD,with XGBoost coming in ***,when the results were visualised,it was discovered that the XGBoost model was more suitable for the problem being *** XGBoost model was a better predictor within the sandstone interval,while the Extra-Trees model was more appropriate in non-sandstone *** this study aims to predict permeability in the reservoir interval,the XGBoost model is the most *** contrasting results demonstrate the importance of incorporating data visualisation techniques as an evaluation *** the heterogeneity of the subsurface,relying solely on statistical metrics may not be sufficient to determine which model is best suited for a particular problem.

关键词： Data visualisation Permeability Machine learning Statistical metrics

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