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Journal of Forestry Research 2023年第6期34卷 1659-1668页

作者： p.W.west Forest Research Centre Southern Cross UniversityLismoreNSW 2480Australia

Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal *** any tree size,this maximum increased as site productivity ***,the size at which this maximum occurred decreased as productivity *** research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive *** trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth *** was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive *** model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests.

关键词： Growth model Individual tree Maximum growth rate Eucalyptus pilularis physiological eff ects

Do increasing respiratory costs explain the decline with age of forest growth rate?

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Journal of Forestry Research 2020年第3期31卷 693-712页

作者： p.W.west Forest research centre southern cross universitylismorensw 2480australia

Once forests have achieved a full canopy, their growth rate declines progressively with age. This work used a global data set with estimates from a wide range of forest types, aged 20-795 years, of their annual photosynthetic production(gross primary production, Gpp) and subsequent above-plus below-ground biomass production(net primary production, Npp). Both Gpp and Npp increased with increasing mean annual temperature and precipitation. Gpp was then unrelated to forest age whilst Npp declined progressively with increasing age. These results implied that autotrophic respiration increases with age. It has been proposed that Gpp should decline in response to increasing water stress in leaves as water is raised to greater heights as trees grow taller with age. However, trees may make substantial plastic adjustment in mor phology and anatomy of newly developing leaves, xylem and fi ne roots to compensate for this stress and maintain Gpp with age. This work reviews the possibilities that Npp declines with age as respiratory costsincrease progressively in, any or all of, the construction and maintenance of more complex tissues, the maintenance of increasing amounts of live tissue within the sapwood of stems and coarse roots, the conversion of sapwood to hear twood, the increasing distance of phloem transport, increased turnover rates of fine roots, cost of supporting very tall trees that are unable to compensate fully for increased water stress in their canopies or maintaining alive competitively unsuccessful small trees.

关键词： primary production photosynthesis Respiration Biomass growth Ageing

problems with models assessing influences of tree size and inter-tree competitive processes on individual tree growth:a cautionary tale

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Journal of Forestry Research 2022年第2期33卷 565-577页

作者： p.W.west D.A.Ratkowsky Forest Research Centre Southern Cross UniversityLismoreNSWAustralia Tasmanian Institute of Agriculture University of TasmaniaHobartTASAustralia

In forest growing at any one site, the growth rate of an individual tree is determined principally by its size, which reflects its metabolic capacity, and by competition from neighboring trees. Competitive effects of a tree may be proportional to its size;such competition is termed ‘sym-metric’ and generally involves competition below ground for nutrients and water from the soil. Competition may also be ‘asymmetric’, where its effects are disproportionate to the size of the tree;this generally involves competition above ground for sunlight, when larger trees shade smaller, but the reverse cannot occur. This work examines three model systems often seen as exemplars relating individual tree growth rates to tree size and both competitive processes. Data of tree stem basal area growth rates in plots of even- aged, monoculture forest of blackbutt (Eucalyptus pilularis Smith) growing in sub-tropical eastern Australia were used to test these systems. It was found that none could distin-guish between size and competitive effects at any time in any one stand and, thus, allow quantification of the contribution of each to explaining tree growth rates. They were prevented from doing so both by collinearity between the terms used to describe each of the effects and technical problems involved in the use of nonlinear least-squares regression to fit the models to any one data set. It is concluded that quite new approaches need to be devised if the effects on tree growth of tree size and competitive processes are to be quantified and modelled successfully.

关键词： Symmetric competition Asymmetric competition Tree growth rate Growth modeling Nonlinear modeling

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

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Effects of p301L-TAU on post-translational modifications of microtubules in human ipSC-derived cortical neurons and TAU transgenic mice

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Neural Regeneration Research 2025年第8期20卷 2348-2360页

作者： Mohamed Aghyad Al kabbani Christoph köhler Hans Zempel Institute of Human Genetics Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for Molecular Medicine Cologne(CMMC) University of CologneCologneGermany Center Anatomy Department ⅡMedical FacultyUniversity of CologneCologneGermany

TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the *** is missorted and aggregated in an array of diseases known as *** are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing *** impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule *** therefore aimed to study the effects of a disease-causing mutation of TAU(p301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether p301L-TAU causes stability-changing modifications to *** investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or p301L-TAU in human MApT-kO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human p301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the p301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.p301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.p301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic *** sum,p301L-TAU results in changes in micr

关键词： human induced pluripotent stem cell microtubules p301L pR5 mice TAU tauopathy tubulin code

prevalence of transfusion transmissible infections among various donor groups:A comparative analysis

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World Journal of Virology 2025年第1期14卷 108-117页

作者： Sanjay k Thakur Anil k Sinha Santosh k Sharma Aarzoo Jahan Dinesh k Negi Ruchika Gupta Sompal Singh Regional Blood Transfusion Centre Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of Zoology Veer Kunwar Singh UniversityAra 802301BiharIndia Regional Blood Transfusion Centre and pathology Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of Cytopathology ICMR-National Institute of Cancer Prevention and ResearchNoida 201301Uttar PradeshIndia

BACkGROUND Transfusion transmissible infections(TTIs)are illnesses spread through contaminated blood or blood *** India,screening for TTIs such as hepatitis B virus(HBV),hepatitis C virus(HCV),human immunodeficiency virus(HIV)-I/II,malaria,and syphilis is mandatory before blood ***,HCV,HBV,and HIV are the leading viruses causing mortality,affecting millions of people globally,including those with co-infections of HIV/HCV and HIV/*** highlight the impact of TTIs on life expectancy and health risks,such as liver cirrhosis,cancer,and other diseases in individuals with chronic ***,millions of blood donations take place annually,emphasizing the importance of maintaining blood *** To study the prevalence of TTIs,viz.,HBV,HCV,HIV I/II,syphilis,and malaria parasite(Mp),among different blood donor *** The study assessed the prevalence of TTIs among different blood donor groups in Delhi,*** included total donors,in-house donors,total camp donors,institutional camp donors,and community camp *** for HIV,HBV,and HCV were done using enzyme-linked immunosorbent assay,while syphilis was tested with rapid plasma reagins and Mp rapid card *** prevalence of HBV,HCV,HIV,and syphilis,expressed as *** in infection rates between the groups were analyzed usingχ²tests and p-values(less than 0.05).RESULTS The study evaluated TTIs among 42158 blood donors in *** overall cumulative frequency of TTIs in total blood donors was 2.071%,and the frequencies of HBV,HCV,HIV-I/II,venereal disease research laboratory,and Mp were 1.048%,0.425%,0.221%,0.377%,and 0.0024%,***-house donors,representing 37656 donors,had the highest transfusion transmissible infection(TTI)prevalence at 2.167%.Among total camp donors(4502 donors),TTIs were identified in 1.266%of donors,while community camp donors(2439 donors)exhibited a prevalence of 1.558%.Institutional camp donors(2063 donors)had the l

关键词： Blood donors Transfusion transmissible infections Hepatitis B virus Human immunodeficiency virus Hepatitis C virus Malaria parasite Syphilis

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： Siva S.V.p.Sakamuri Anil Sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA Vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

Small molecule inhibitor DDQ-treated hippocampal neuronal cells show improved neurite outgrowth and synaptic branching

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Neural Regeneration Research 2025年第9期20卷 2624-2632页

作者： Jangampalli Adi pradeepkiran priyanka Rawat Arubala p.Reddy Erika Orlov pHemachandra Reddy Department of Internal Medicine Texas Tech University Health Sciences CenterLubbockTXUSA Department of Nutritional Sciences College of Human SciencesTexas Tech UniversityLubbockTXUSA Department of pharmacology&Neuroscience Texas Tech University Health Sciences CenterLubbockTXUSA Department of Neurology Texas Tech University Health Sciences CenterLubbockTXUSA Department of Speech Language and Hearing SciencesTexas Tech University Health Sciences CenterLubbockTXUSA Department of public Health Texas Tech University Health Sciences CenterLubbockTXUSA

The process of neurite outgrowth and branching is a crucial aspect of neuronal development and *** and dendrites,sometimes referred to as neurites,are extensions of a neuron's cellular body that are used to start *** we explored the effects of diethyl(3,4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ)on neurite developmental features in HT22 neuronal *** this work,we examined the protective effects of DDQ on neuronal processes and synaptic outgrowth in differentiated HT22cells expressing mutant Tau(mTau)*** investigate DDQ chara cteristics,cell viability,biochemical,molecular,western blotting,and immunocytochemistry were *** outgrowth is evaluated through the segmentation and measurement of neural *** neural processes can be seen and measured with a fluorescence microscope by manually tracing and measuring the length of the neurite *** neuronal processes can be observed and quantified with a fluorescent microscope by manually tracing and measuring the length of the neuronal ***-treated mTau-HT22 cells(HT22 cells transfected with cDNA mutant Tau)were seen to display increased levels of synaptophysin,MAp-2,andβ-***,we confirmed and noted reduced levels of both total and p-Tau,as well as elevated levels of microtubule-associated protein 2,β-tubulin,synaptophysin,vesicular acetylcholine transporter,and the mitochondrial biogenesis protein-pe roxisome prolife rator-activated receptor-gamma coactivator-1α.In mTa u-expressed HT22 neurons,we observed DDQ enhanced the neurite characteristics and improved neurite development through increased synaptic *** findings conclude that mTa u-HT22(Alzheimer's disease)cells treated with DDQ have functional neurite developmental chara *** key finding is that,in mTa u-HT22 cells,DDQ preserves neuronal structure and may even enhance nerve development function with mTa u inhibition.

关键词： diethyl(3 4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ) hippocampal neuronal cells HT22 neurite outgrowth neuronal development small molecule

CRITICAL ISSUES OF pOWDER METALLURGY TURBINE DISkS

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 467-471页

作者： k.M. Chang(Department of Mechanical and Aerospace Engineering,west Virginia University, p.O. Box 6160, Morgantown,WV 26506, USA west Virginia Univ Morgantown United States

p/M superalloy disks obtain their final strength by appropriate heat treatments; the maximum attainable strength depends on the rapid cooling rate from the solution annealing. A rapid quench of a large disk forging can cause two problems, surface cracking and shape *** the past,many attempts employ the finite element code to model and to predict temperature evolution and induced stress distribution in a large turbine disk. The major difficulty was the correct description of alloy behavior; particularly the thermomechanical properties and the failure criteria of material during the cooling. High temperature fatigue resistance is always the key requirement for disk materials. New methodology of residual life management emphasizes the initiation as well as the propagation of the cracks developed under the service conditions. One of major challenges to p/M superalloys is the time-dependent behavior of fatigue cracking, which relates to the well-known SAGBO (stress-assisted grain boundary oxidation) phenomenon.A great effort has been done to understand the micro-mechanism of time-dependent fatigue crack propagation resulted in the second generation of p/M superalloys. Further improvement on temperature capability of disk alloys at rim area may lead to the idea of dual-property *** grain structures at different portions of a large disk are possible,as the property requirements for different locations are different. This goal is achievable if the thermal history at specific disk locations can be controlled to develop desirable microstructures and *** suggestions on the future direction of research efforts will be discused.

关键词： superalloy disk,powder metallurgy (p/M) quench cracking,fatigue crack propagation SAGBO (stress-assisted grain boundary oxidation),dual-property disk grain size

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris k.Salgado Jose M.Santiago Samuel E.Ocasio Rivera Dina p.Bracho-Rincon Luis H.pagan Rivera Jorge D.Miranda Department of physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma