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Tree regeneration in gap-understory mosaics in a subtropical Shorea robusta(Sal) forest

Journal of Forestry Research 2019年第6期30卷 2061-2068页

作者： L.N.Sharma K.b.Shrestha I.e.Maren Forest Action Nepal GPO-12207 LalitpurNepal Department of biological Sciences University of BergenThormoensgate 53B5007 BergenNorway

Spatial variation in tree-regeneration density is attributed to the specialization of tree species to light availability for germination and *** availability,in turn,varies across the gap-understorey *** gaps provide an important habitat for the regeneration of tree species that would otherwise be suppressed in the *** subtropical forests,there is still a knowledge-gap relating to how canopy disturbances influence tree-regeneration patterns at local scale,and if they disproportionately favor regeneration of certain *** aim to analyze whether canopy gaps promote tree regeneration,and tree species are specialized to gaps or understory for germination and *** sampled vegetation in 128 plots(0.01 ha),equally distributed in gaps and below canopy,in two subtropical Shorea robusta Gaertn.(Sal)forests in Nepal,recording the number of tree seedlings and saplings in each *** compared the regeneration density of seedlings and saplings separately between gaps and the *** mean densities of seedlings and saplings were higher in the gaps at both sites;although there was no difference in the seedling density of the majority of the species between the *** species were confined to either gap or understorey at the seedling *** conclude that gaps are not critical for the germination of tree species in Sal forests but these are an important habitat for enabling seedlings to survive into *** classification of trees into regeneration guilds mainly based on germination does not apply to the majority of tree species in subtropical Sal *** results reaffirm that gap creation promotes tree regeneration by favouring seedling survival and growth and can influence forest management for conservation,as well as for plantations.

关键词： Canopy-gap Density Regeneration Saplings Seedlings Shade tolerance

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An efficient boron Source Activation Strategy for the Low‑Temperature Synthesis of boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng e Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(bNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–b *** approach can be adopted to form various low-melting-point AM–Mg–b–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of bNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form bN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of bNNTs.

关键词： boron nitride nanotubes Low-temperature boron activation Density functional theory

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Space-to-space Radio Interferometry System from Medium earth Orbits

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空间科学学报 2019年第4期39卷 544-562页

作者： MARTIN-NeIRA M KUDRIASHOV V bARAT I DUeSMANN b DAGANZO e european Space Research and Technology Centre European Space Agency

This paper presents a new concept to perform space-to-space Very Long baseline Interferometry which enables the imaging of cosmic sources at high-resolution and high-sensitivity with small *** individual apertures are embarked on separate identical satellites staggered in height into Polar or equatorial Circular Medium earth Orbits(PeCMeO orbits).These orbits are stable and allow GNSS-based on-the-fly centimeter-level relative *** operation is possible by exchanging local oscillator components and measured signals through Inter-Satellite Links(ISL).On-board cross correlation is performed at each satellite over a delay window compatible with the accuracy of the on-the-fly relative positioning and the result sent to the *** reconstruction is completed on the ground thanks to sub-millimeter baseline retrieval from accurate GNSS orbits,ISL ranging and spacecraft attitude *** application of this concept to image the Super Massive black Hole Sgr A*is hinted.

关键词： Space-to-space interferometry event horizon Space radio-astronomy

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Dendritic spine density changes and homeostatic synaptic scaling:a meta-analysis of animal studies

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Neural Regeneration Research 2022年第1期17卷 20-24页

作者： Thiago C.Moulin Danielle Rayêe Helgi b.Schiöth Functional Pharmacology Unit Department of NeuroscienceUppsala UniversityUppsalaSweden Institute of Medical biochemistry Federal University of Rio de JaneiroRio de JaneiroBrazil Institute of biomedical Sciences Federal University of Rio de JaneiroRio de JaneiroBrazil Department of Ophthalmology and Visual Sciences Albert Einstein College of MedicineNYUSA Institute for Translational Medicine and biotechnology Sechenov First Moscow State Medical UniversityMoscowRussia

Mechanisms of homeostatic plasticity promote compensatory changes of cellular excitability in response to chronic changes in the network *** type of plasticity is essential for the maintenance of brain circuits and is involved in the regulation of neural regeneration and the progress of neurodegenerative *** of the most studied homeostatic processes is synaptic scaling,where global synaptic adjustments take place to restore the neuronal firing rate to a physiological range by the modulation of synaptic receptors,neurotransmitters,and ***,despite the comprehensive literature on the electrophysiological properties of homeostatic scaling,less is known about the structural adjustments that occur in the synapses and dendritic *** this study,we performed a meta-analysis of articles investigating the effects of chronic network excitation(synaptic downscaling)or inhibition(synaptic upscaling)on the dendritic spine density of *** results indicate that spine density is consistently reduced after protocols that induce synaptic scaling,independent of the intervention ***,we discuss the implication of our findings to the current knowledge on the morphological changes induced by homeostatic plasticity.

关键词： chronic inhibition chronic stimulation dendritic spines downscaling excitability homeostatic plasticity spine density synaptic scaling upscaling

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Role of vitamin b12 deficiency in ischemic stroke risk and outcome

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Neural Regeneration Research 2021年第3期16卷 470-474页

作者： Gyllian b.Yahn Jamie e.Abato Nafisa M.Jadavji Department of biomedical Sciences Midwestern UniversityGlendaleAZUSA Department of Neuroscience Carleton UniversityOttawaONCanada

Currently,ischemic stroke is the most prevalent form of stroke compared to hemorrhagic and there is a high incidence in older *** is a modifiable risk factor for stroke.b-vitamins are part of a metabolic network that integrates nutritional signals with biosynthesis,redox homeostasis,and *** vitamins play an essential role in the regulation of cell proliferation,stress resistance,and embryo development.A deficiency in vitamin b12 is common in older adults and has been reported to be implicated in ischemic *** aim of this review was to investigate whether vitamin b12 deficiencies impact the risk and outcome of ischemic *** data from our literature review strongly suggest that a deficiency in vitamin b12 is a risk factor for ischemic stroke and possible *** survey of the literature has identified that there is a gap in the understanding of the mechanisms through which a vitamin b12 deficiency leads to an increased risk of stroke and outcome.A vitamin b12 deficiency can increase homocysteine levels,which are a well-established risk factor for ischemic *** potential mechanism through which vitamin b12 deficient may impact neurological function and increase risk of stroke,is changes in myelination,however this link requires further *** studies are required in model systems to understand how a vitamin b12 deficiency changes the brain.

关键词： b-vitamins ischemic stroke one-carbon vitamin b12

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Characteristic evaluation on spray-deposited WFTO thin films as a function of W doping ratio

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Rare Metals 2014年第4期33卷 433-441页

作者： G.Turgut e.F.Keskenler S.Aydin D.Tatar e.Sonmez S.Dogan b.Duzgun Department of Physics education Kazim Karabekir Education FacultyAtatürk University Department of Nanotechnology Faculty of EngineeringRecep Tayyip Erdogan University Department of electrical and electronics engineering Faculty of Engineering and ArchitectureBalikesir University

Abstract In this work, F and F ＋ W simultaneously doped SnO2 highly transparent conducting thin films were depos- ited on glass substrates at （500 4± 5） ℃ temperature by the spray pyrolysis method. Microstructural, morphological, electrical and optical properties of FrO films were investi- gated as a function of tungsten （W） doping, in the range from 0 to 5 at%. X-ray diffraction patterns show that the films exhibit a tetragonal cassiterite structure and （200） preferen- tial orientation of FTO film, and the relative strength of these peaks changes with altering the W doping ratio. The pre- ferred growth of （211） changed to （200） plane with 2 at% W doping level and 3 at% W-doped film had （200） orientation and with further doping, this changed to （110） orientation. The scanning electron microscopy and atomic force microscopy images of the films indicate that the films are made up of dense small particles of a pyramidal shape and have a smooth surface. It was observed that the surface morphology of the films did not change much when the W element was inserted to the FrO structure. It was found that the sheet resistance values of the films varied with W doping ratio, and 2 at% W-doped FTO thin film exhibited the lowest values of sheet resistance （1.12Ω）. Also, the highest figure of merit, infrared reflectivity and optical band gap values werecalculated for 2 at% W-doped FTO film as 50.9× 10-2 Ω-1, 98.82 % and 4.13 eV, respectively. These results make the films an effective candidate for usage in many optoelectronic applications and photo-thermal conversion of solar energy.

关键词： WFTO FrO Spray pyrolysis Thin films Lattices

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effect of wall temperature and random distribution of micro organic dust particles on their combustion parameters

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Journal of Central South University 2015年第10期22卷 3888-3899页

作者： M.bidabadi e.Yaghoubi M.Harati Gh.Shahryari b.Akhoondian Department of Mechanical engineering Iran University of Science and Technology Combustion Research Laboratory

The effect of wall temperature on the characteristics of random combustion of micro organic particles with recirculation was investigated. The effect of recirculating in micro-combustors is noticeable, hence it is necessary to present a model to describe the combustion process in these technologies. Recirculation phenomenon is evaluated by entering the exhausted heat from the post flam zone into the preheat zone. In this work, for modeling of random situation at the flame front, the source term in the equation of energy was modeled considering random situation for volatizing of particles in preheat zone. The comparison of obtained results from the proposed model by experimental data regards that the random model has a better agreement with experimental data than non-random model. Also, according to the results obtained by this model, wall temperature affects the amount of heat recirculation directly and higher values of wall temperature will lead to higher amounts of burning velocity and flame temperature.

关键词： random combustion recirculation micro organic particle effective equivalence ratio flame temperature burning velocity

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Novel therapeutic strategies targeting mitochondria as a gateway in neurodegeneration

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Neural Regeneration Research 2023年第5期18卷 991-995页

作者： Diogo Trigo Jose Joao Vitoria Odete A.b.da Cruz e Silva Neuroscience and Signalling Laboratory Institute of Biomedicine(iBiMED)Department of Medical SciencesUniversity of AveiroAveiroPortugal

In recent years, multiple disciplines have focused on mitochondrial biology and contributed to understanding its relevance towards adult-onset neurodegenerative disorders. These are complex dynamic organelles that have a variety of functions in ensuring cellular health and homeostasis. The plethora of mitochondrial functionalities confers them an intrinsic susceptibility to internal and external stressors(such as mutation accumulation or environmental toxins), particularly so in long-lived postmitotic cells such as neurons. Thus, it is reasonable to postulate an involvement of mitochondria in aging-associated neurological disorders, notably neurodegenerative pathologies including Alzheimer’s disease and Parkinson’s disease. On the other hand, biological effects resulting from neurodegeneration can in turn affect mitochondrial health and function, promoting a feedback loop further contributing to the progression of neuronal dysfunction and cellular death. This review examines state-of-the-art knowledge, focus on current research exploring mitochondrial health as a contributing factor to neuroregeneration, and the development of therapeutic approaches aimed at restoring mitochondrial homeostasis in a pathological setting.

关键词： Alzheimer’s disease axon energy homeostasis glymphatic system mitochondria mitostasis neurodegeneration neuroregeneration Parkinson’s disease therapeutical strategies

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Linking monitoring and modelling for river basin management:Danish experience with combating nutrient loadings to the aquatic environment from point and non-point sources

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Science China(Technological Sciences) 2009年第11期52卷 3335-3347页

作者： KRONVANG brian WINDOLF JФrgen GRANT Ruth ANDeRSeN Hans e THODSeN Hans OVeSeN Niels b LARSeN SФren e National environmental Research Institute Aarhus University VejlsФvej 25 DK-8600 Silkeborg Denmark

Nationwide monitoring of the aquatic environment was initiated in 1988 in Denmark as a means to follow the outcome of the Action Plans for nutrient pollution of the aquatic environment. Five Action Plans have been adopted by the Danish Parliament since 1985 and the nationwide monitoring programme can be used to quantify the outcome as shown by reductions in nutrient discharges from both point and non-point sources. Moreover, the empirical experience gathered from nearly 20 years of monitoring is assisting the development and calibration of models for simulation of nitrogen leaching, nitrogen removal in groundwater and surface waters and the establishment of a P-index all covering the entire land area of Denmark.

关键词： nitrogen phosphorus monitoring data point sources non-point sources models Action Plans Danish experience

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Computational modeling of free-surface slurry flow problems using particle simulation method

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Journal of Central South University 2013年第6期20卷 1653-1660页

作者：赵崇斌彭省临刘亮明 b.e.Hobbs A.Ord Computational Geosciences Research Centre Central South University School of earth and environment The University of Western Australia

The particle simulation method is used to solve free-surface slurry flow problems that may be encountered in several scientific and engineering *** main idea behind the use of the particle simulation method is to treat granular or other materials as an assembly of many *** with the continuum-mechanics-based numerical methods such as the finite element and finite volume methods,the movement of each particle is accurately described in the particle simulation method so that the free surface of a slurry flow problem can be automatically *** major advantage of using the particle simulation method is that only a simple numerical algorithm is needed to solve the governing equation of a particle simulation *** the purpose of illustrating how to use the particle simulation method to solve free-surface flow problems,three examples involving slurry flow on three different types of river beds have been *** related particle simulation results obtained from these three examples have demonstrated that:1) The particle simulation method is a promising and useful method for solving free-surface flow problems encountered in both the scientific and engineering fields;2) The shape and irregular roughness of a river bed can have a significant effect on the free surface morphologies of slurry flow when it passes through the river bed.

关键词： particle simulation free surface slurry flow numerical method

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